<figure><img src="image_321.png" /></figure>

ly survive in the harsh conditions in which they grow. While studies are continuing, progress is slow, and due to the decline in the number of active Australian bryologists, conservation of rare, threatened, or vulnerable species is well behind that for other plant groups. We conclude by summarising the conservation efforts that are currently being undertaken in Australia in the Mediterranean biome.

## S.136.6 Green Canopies and Cityscapes: Decoding Urban Epiphytic Bryophyte Diversity in Novi Sad, Serbia – A Phorophyte Puzzle

Miloš Ilić¹, Ankica Milovanović¹, Ivana Blanuša¹, Boris Radak¹, Mirjana Ćuk¹, Tijana Šikuljak¹, Dragana Vukov¹

1 University of Novi Sad, Faculty of sciences, Department of Biology and Ecology, Novi Sad, Serbia

There is a notable gap in our understanding of the primary factors influencing epiphytic bryophyte diversity in urban areas. This study aims to provide fresh insights into the intricate web of epiphytic diversity within urban landscapes, specifically investigating whether phorophyte type exerts a predominant influence on bryophyte diversity compared to other tree characteristics. The survey encompassed seven locations in Novi Sad City, including three city parks and four main boulevards. All epiphytic bryophyte species were meticulously recorded across these sites, revealing a total of 35 species. To quantify bryophyte abundance, we utilized the microplot sampling method, employing microplots (10×10 cm) at a 20 cm distance on all four sides of each tree, from the base up to the 2 m heigh. Alpha-diversity measures included species richness, the Shannon diversity index, and the Pielou evenness index. The Sörensen similarity index served as a non-parametric beta diversity measure to assess the similarity between different locations. Environmental drivers, such as bark pH, tree diameter at breast height, bark structure, tree height, and phorophyte type, were incorporated. Multivariate analysis, specifically Canonical Correspondence Analysis (CCA) and Variation Partitioning, were employed to test the impact of environmental variables on epiphytic bryophyte diversity. The highest Shannon diversity index was observed on *Celtis occidentalis* and *Populus alba* trees, while *Betula pendula* and *Styphnolobium japonicum* exhibited the highest evenness index. CCA analysis indicated that the most influential explanatory variable

was phorophyte type, explaining approximately 30% of the total variability. Tree height, tree diameter, bark pH, and structure significantly influenced the Shannon diversity index of epiphytic bryophytes, accounting for approximately 5% of the total variability. While this study underscores the predominant influence of phorophyte type on epiphytic bryophyte diversity, further research is warranted to unravel unexplained variations, possibly attributable to microclimatic conditions.

## S.136.7 Bryo-ecological patterns in Mediterranean temporary ponds: a highly sensitive proxy for habitat monitoring

Silvia Poponessi¹, Daniela Gigante², Annalena Cogoni¹

1 Department of Environmental and Life Science, Botany section, University of Cagliari, Cagliari, Italy.

2 Department of Agricultural, Environmental, and Food Science, University of Perugia, Perugia, Italy

This study contributes to the knowledge and understanding of Annex I priority habitat 3170*, where bryophytes play an essential role in the ecological patterns and are a significant indicator, especially concerning habitat monitoring, assessment, and management. In this paper, we analyze the bryological component of Mediterranean temporary ponds in two different areas in the Mediterranean Biogeographic Region, such as the “Pauli” of Giara di Gesturi in Sardinia (a Mediterranean island), and the Piana di Ferretto in Umbria (inland Central Italy), comparing the rate of bryophytes occurrence. The detected species are described in terms of their functional characteristics using Ellenberg values adapted for bryophytes. More specifically, the following parameters are considered: life strategy, life macroform, light and moisture preferences, chorological elements and humidity Belt. We focused on the distribution of bryophytes along concentric areas of the pools according to their humidity gradient. On this ground, the bryological flora of the studied Mediterranean temporary ponds was characterized from an ecological point of view. To account for ecological variability, data from the two areas were compared. Temporary Mediterranean ponds represent vulnerable niches where climate change is exerting its influence. The approach used in this study could be extended to comparable Mediterranean habitats, focusing on bryological ecology as an effective proxy for habitat monitoring under a scenario of unpredictable climate change.
# S.137 USING HIGH-THROUGHPUT SEQUENCING TO UNDERSTAND PLANT EVOLUTION ON ISLANDS IN A DATA-RICH ERA: NEW INSIGHTS FOR NEW CHALLENGES. SESSION 1

## S.137.1 Genome-wide data provide new insights into the phylogenetic relationships within the woody Sonchus alliance (Asteraceae)

Seon-Hee Kim¹, Koji Takayama¹, Imai Ryosuke², Masuda Sachiko³, Shibata Arisa³, Shirasu Ken³, Arnoldo Santos-Guerra⁴, Seung-Chul Kim⁵

1 Department of Botany, Graduate School of Science, Kyoto University, Kyoto, Japan. 2 Forest Research and Maintenance Organization, Matsunosato, Tsukuba, Ibaraki, Japan. 3 RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa, Japan. 4 Tegueste, Tenerife, Canary Islands, Spain. 5 Department of Biological Sciences, Sungkyunkwan University, Suwon, Republic of Korea

Numerous unique plant groups have made the Macaronesian Islands an exceptional area for studying evolution and speciation. Of several iconic angiosperm groups, the woody *Sonchus* alliance, which includes approximately 31 species in the Canaries, Madeira, and Cape Verde, represents one of the best-known examples of adaptive radiations. It has been difficult to unravel rapidly radiated inter-specific relationships using conventional molecular markers (e.g., nrDNA ITS and chloroplast noncoding regions) due to the insufficient resolution and support. In order to clarify the biogeographic and evolutionary history of the alliance, we used the complete chloroplast genome and double-digest restriction site-associated DNA sequence (ddRAD-seq) data based on the thorough species coverage and multiple populations per species. The complete plastome sequences of 135 accessions provided well resolved strongly supported phylogenetic relationships but revealed non-monophyly of numerous species and unusual species relationships, suggesting rampant chloroplast polymorphisms. As previously suggested, the early

divergence of segregate genera, *Sventenia*, *Chrysooprenanthes*, *Babcockia*, and *Lactucosonchus*, was supported. With 95 accessions, ddRAD-seq data also provided a fully resolved and highly supported phylogenetic framework for the alliance, while better reflecting species morphological and biogeographic relationships and revealing monophyly in most species. Newly inferred species relationships, timing of lineage divergence, and biogeographic history of the alliance based on the genome-wide nuclear data will be presented.

## S.137.2 Great speciators of the plant world: Island biogeography of Asteraceae on Hawai'i and the Mascarenes

Lizzie Roeble¹,², Marina Ventayol García¹, Claudia Baider³, Vincent Florens⁴, Matthew Knope⁵, Joshua Lambert², David Lorence⁶, Cliff Morden⁷, Dominique Strasberg⁸, Christophe Thébaud⁹, Kenneth Wood⁶, Rampal S. Etienne², Luis Valente¹,²

1 Naturalis Biodiversity Center, Leiden, The Netherlands. 2 Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands. 3 The Mauritius Herbarium, Agricultural Services, Ministry of Agro-Industry and Food Security, Reduit, Mauritius. 4 Tropical Island Biodiversity, Ecology and Conservation Pole of Research, Faculty of Science, University of Mauritius, Le Réduit, Mauritius. 5 University of Hawai'i at Hilo, Dept. of Biology, Hilo, HI, USA. 6 National Tropical Botanical Garden, Kalaheo, Hawaii, USA. 7 School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, Hawai'i, USA. 8 Peuplements Végétaux et Bioagresseurs en Milieu Tropical, UMR PVBMT, Université de La Réunion, SaintDenis, La Réunion, France. 9 Laboratoire Évolution and Diversité Biologique (UMR 5174), CNRS-IRD- Université Paul Sabatier (Toulouse 3), Toulouse, France.
<figure><img src="image_322.png" /></figure>

Macroevolutionary models of island biogeography applied to high-throughput DNA sequencing data on island species are promising tools for inferring the processes governing biota assembly for entire communities over evolutionary time scales. However, to date, phylogenetic trees of island plant lineages that can be used for studying island biogeography have mostly been reconstructed using a limited number of loci, often leading to poor resolution, particularly in rapidly evolving insular radiations. Asteraceae - the largest plant family in the world - provides an excellent model system for looking at diversity dynamics on islands, due to this group's high diversity, endemism, and number of radiations across islands globally. In particular, the Asteraceae floras of two remote oceanic archipelagos - Hawai'i and the Mascarenes - are remarkably diverse. The Hawaiian Islands have 99 native Asteraceae species of which 98 are endemic, and are home to the iconic silversword alliance, a textbook example of adaptive radiation. The Mascarenes also have a high proportion of Asteraceae endemism (89%), but until now most of the native Asteraceae lineages on the Mascarenes have not been studied in a phylogenetic context. Here, we compile and build new dated phylogenies with target capture sequencing (Hyb-Seq) using both the Angiosperm-353 and the Compositae-1061 kits for all the native Asteraceae lineages that have colonized these two isolated oceanic archipelagos. We then use a macroevolutionary island biogeography model (DAISIE) to analyze and reconstruct the build-up of the diversity for the entire native Asteraceae assemblage on Hawai'i and the Mascarenes. Our approach using target-capture sequencing allows us to infer the number of colonization and radiation events with increased precision, estimate macroevolutionary rates of colonization, speciation and extinction, and to test whether these systems are at equilibrium.

## S.137.3 The Paradox of Insular Diversification: How Can Lineages Depleted of Genetic Variation Radiate on Islands? Insights from the Galápagos

José Cerca¹, Juan Ernesto Guevara Andino², Gonzalo Rivas-Torres³,⁴, Michael D. Martin⁵

1 Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, Oslo, Norway. 2 Grupo de Investigación en

Ecología y Evolución en los Trópicos, Universidad de las Américas, Quito, Ecuador. 3 Estación de Bio-diversidad Tiputini, Colegio de Ciencias Biológicas y Ambientales, Universidad San Francisco de Quito, Quito, Ecuador. 4 Universidad San Francisco de Quito, Cumbayá, Quito, Ecuador. 5 Department of Natural History, NTNU University Museum, Norwegian University of Science and Technology, Trondheim, Norway

Despite the constraints imposed by founder events, small population sizes, and inbreeding, some oceanic lineages exhibit an astonishing degree of ecological and phenotypic diversity. This intriguing paradox raises a fundamental question: how do isolated lineages generate and maintain genetic diversity? While de novo mutation, the traditional source of genetic variation, is widely considered too slow to account for the observed levels of ecological differentiation and divergence in these lineages, alternative mechanisms remain elusive. In this work, we explore the role of diverse genomic architectures in fostering genetic diversity. With a focus on the adaptive radiation of Scalesia, we investigate the contribution of transposable elements and polyploidization to the generation of genetic variation. Our findings reveal an even distribution of transposable elements across subgenomes and a lack of association between ecological niche, phylogeny, and transposable element accumulation. Collectively, these results suggest that transposable elements may not have played a significant role in shaping this adaptive radiation.

## S.137.4 Genomic dissection of island syngameons: arborescent Asteraceae from St Helena (South Atlantic Ocean)"

Mikko Paajanen¹, Quentin C. Cronk¹

1 Department of Botany, University of British Columbia, Vancouver, Canada

The genera *Commidendrum* (4 spp.) and *Melanodendron* (1 sp.) from St Helena (South Atlantic Ocean) form a single clade whose ancestor reached the island in the early Pliocene. All species have highly divergent morphologies linked to ecology. *Commidendrum* and *Melanodendron* are known to form an intergeneric hybrid and *Commidendrum* is known to form interspe-
<figure><img src="image_323.png" /></figure>

cific hybrids. Plant genomics can untangle evo-
lutionary history as well as complex histories of
hybridization on islands. Genomic evidence is
presented that hybridization has occurred in the
*Commidendrum/Melanodendron* clade due to
recent conservation efforts due to planting spe-
cies in proximity. Furthermore, there is genomic
evidence that hybridization events may be an-
cient, with the species forming a syngameon,
so raising the genetic effective population sizes
(N<sub>6</sub>) of species. A syngameon is here defined as:
"a group of otherwise distinct species intercon-
nected by limited gene exchange, i.e., the most
inclusive interbreeding evolutionary unit" (Su-
arez-Gonzalez et al., "Adaptive introgression: a
plant perspective" Biology Letters 2017). Such hy-
bridization events are postulated to be a contin-
ual source of background 'evolutionary rescue' of
species from any small population size impacts
over geological time, a phenomenon of particu-
lar importance and impact on islands. Genomic
studies are an essential tool for the study of plant
evolution on islands, and for endemic plant con-
servation.

S.137.6 Phylogenomics
of the hyperdiverse
Asteraceae family in an
oceanic archipelago:
unveiling insights into the
mechanisms of evolution

Yurena Arjona¹,², Louis S. Jay-García¹,²,
Alfredo J. Reyes-Betancort³, Marcos
Salas-Pascual⁴, Miguel Padrón-Mederos²,
Agustín Naranjo-Cigala⁴, Javier Morente-
López², Stephan Scholz⁵, Jairo Patiño¹,²

1 Instituto de Productos Naturales y Agrobiología, Spanish National Research Council (CSIC), La Laguna, Spain. 2 Universidad de La Laguna, La Laguna, Spain. 3 Jardín de Aclimatación de La Orotava, Puerto de La Cruz, Spain. 4 Universidad de Las Palmas de Gran Canaria, Tafira Baja, Spain. 5 Jardín Botánico Oasis Wildlife Fuerteventura, La Lajita, Fuerteventura, Spain

Invasive species pose a significant threat to bio-
diversity, particularly on oceanic islands. The na-
tive biota of oceanic islands is both fragile and
unique, rendering these ecological systems es-
pecially susceptible to biological invasions and

other anthropogenic disturbances. Despite this
recognition, the mechanisms driving the success
of invasive species remain uncertain. Charles
Darwin proposed two competing hypotheses,
collectively known as Darwin's Naturalization
Conundrum (DNC), to predict a species' inva-
sive potential. The first hypothesis, termed the
"Pre-adaptation Hypothesis," posits that species
closely related to the native community are more
likely to invade successfully. This is attributed to
their possession of similar life-history traits that
pre-adapt them to establish and thrive under
the local environmental conditions (environmen-
tal filtering). Conversely, the "Naturalization Hy-
pothesis" suggests that species distantly related
to native species can exploit empty ecological
niches, avoiding competitive exclusion and thus
exhibiting a higher potential for invasion (biot-
ic filtering). Herein, we present the findings of a
long-term project, **ASTERALIEN**, focused on test-
ing the DNC within the Compositae family across
the Canary Islands. We explored the DNC by ex-
amining two dimensions of relatedness between
species: phylogenetic and functional distance.
Utilizing a comprehensive phylogenomic ap-
proach to infer a super-tree encompassing all
genera and a majority of species in the archipel-
ago, we assessed the phylogenetic relatedness
between alien and native species. This super-tree
is constructed using hybrid capture-based tar-
get enrichment of the angiosperm-wide 353 and
the Asteraceae family-specific 1061 probe sets
for approximately 300 species. The integration
of measured functional traits of all species col-
lected in the field allow us to estimate functional
distances between these two (naive vs. exotic)
distinct functional groupings. By integrating both
phylogenomic and functional approaches at un-
precedent resolution, our study explicitly evalu-
ates the mechanisms of evolution and invasion
in alien species on oceanic islands within the
framework of the DNC.
<figure><img src="image_324.png" /></figure>

# S.138 PHYLOGENOMICS AND EVOLUTION OF GYMNOSPERM

## S.138.1 Phylogenomics shed new light on the evolutionary history of Cupressaceae

Jialiang Li¹, Wentao Wang¹, Kangshan Mao¹

1 College of Life Sciences, Chengdu, Sichuan, P.R. China

As one of the largest families of gymnosperms, Cupressaceae comprises above 162 species (32 genera, seven subfamilies), and is the only gymnosperm group occurring on all continents except Antarctica. The world-wild distribution and high species diversity make this family an ideal example for exploring evolutionary history of the global intercontinental floras. Here we conducted a comprehensive phylogenomic study of Cupressaceae using more than 2000 single copy nuclear genes with a nearly complete sampling of species. Species tree reconstruction suggest that all genera and subfamilies were well-supported monophylies. Unexpectedly, we found the subfamily Athrotaxidoideae, which was sister to the remaining four subfamilies except Cunninghamioideae and Taiwaniaideae in previous studies, was clustered with Sequoioideae. Results of concordance analysis showed a high level of gene tree conflict of the ancestral node of Athrotaxidoideae and Sequoioideae, suggesting it might have experience rapid speciation event and/ or hybridization. PhyloNet analyses suggested three reticulation events within Cupressaceae at subfamily level. Molecular clock estimation revealed that two diverse evolutionary lineages (the tribe Cupresseae and Callitris), which together comprise ~70% of the species of Cupressaceae, underwent rapid diversification around the Cretaceous-Paleogene (K-Pg) boundary. A diversification rate shift was also detected along the ancestral branch of the tribe Cupresseae, corresponding a rate shift in phenotypic evolution. Biogeographical analyses suggest that the current distribution pattern of Cupressioideae and Callitroideae is largely associated with the breakup of Pangea, yet the detailed spatiotemporal evolutionary history is different from previous studies. In short, our phylogenomic survey suggest that the evolutionary history of Cupressaceae is more complex than previously thought.

## S.138.2 Of signals and synthesis: the evolutionary implications of chemical signal divergence and its relationship to biosynthetic pathways in

Gwen M. Bode¹, Shayla Salzman¹

1 Department of Entomology, University of Georgia, Athens, Georgia USA

The staggering diversity of mutualistic interactions found in nature, has long been a topic of fascination to science, with studies of chemically-mediated ecological interactions contributing great strides in our understanding. Investigations on the chemical ecology of ancient insect-polinated plant lineages provides critical insight into the myriad ways such mutualistic diversity could evolve. Brood-site pollination mutualism of cycads, an early-diverging lineage of gymnosperms, is the most ancient pollination mechanism yet documented; pre-dating even the rise and dominance of flowering plants. Cycad pollination is a classic example of a brood-site pollination mutualism, wherein pollinators develop within the reproductive tissue of their host plant, relying on them for shelter, food, and in this case, breeding site. Cycads' chemically mediated 'push-pull' mechanism ensures pollinators visit both pollen and ovulate cones through thermogenically driven increases in the concentration of cone volatiles (scent) that results in a mass excess of pollinators from pollen cones and simultaneous attraction to conspecific ovulate cones. *Zamia*, a genus of cycads found widely dispersed across the Americas and the Caribbean, are polinated by a group of specialist brood-site mutualists, the cycad weevils (Subtribe: Allocorynina). The Caribbean *Zamia* clade, shows remarkable diversity in cone volatile composition that appears to be both species-specific and rapidly evolving under positive selection suggesting that plant chemistry is integral for maintaining species boundaries, yet we remain woefully unaware of how plant volatile chemistry related to
<figure><img src="image_325.png" /></figure>

pollination evolves across a lineage. In this study we conduct a deep exploration of the chemical communication across the Caribbean *Zamia* clade by characterizing the quantitative patterns of cone volatile chemical composition in a phylogenetic and biogeographic context. We discuss the biosynthetic origins of biologically relevant compounds and the evolutionary implications of diverging signals.

## S.138.3 Multidisciplinary approaches reveal the spatiotemporal evolution of gymnosperms

Xiao-Quan Wang¹

1 State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, the Chinese Academy of Sciences, Beijing, China

Reconstructing the phylogenetic history of organisms and understanding what determines the distribution of species diversity remain challenging in evolutionary biology and ecology. This is particularly true for gymnosperms, which comprise only 13 families and a little more than 1,000 species. Although greatly outnumbered by the species of angiosperms, gymnosperms have huge ecological and economic value, of which conifers (about 615 species) constitute approximately 39% of the world's forests. In addition, the Northern Hemisphere conifers do not follow a latitudinal diversity gradient and show a unique distribution pattern, i.e., most species are distributed in mountainous areas at middle latitudes. It is of great interest to investigate the spatiotemporal evolution of gymnosperms, especially conifers. In recent years, we have used phylogenies to robustly reconstruct the phylogeny of gymnosperms at both higher (interfamilial and intergeneric) and lower (interspecific) taxonomic levels, and employed multidisciplinary approaches to reveal the mechanisms underlying diversification and global distribution of conifers, including Gnetales. Our studies indicate: (1) Podocarpaceae originated in Gondwana in the late Triassic, and both vicariance and dispersal contributed to its current biogeographic patterns; (2) Cupressaceae very likely originated in Asia in the Triassic, and geographic isolation caused by continental separation drove the vicariant evolution of the two subfamilies Cupressoideae and Callitroideae in

the northern and southern hemispheres, respectively; (3) The mid-latitude region has provided an evolutionary museum for global pines, topography played a primary role in pine diversification, and the aridity index was decisive for the niche rate shift; and (4) *Ephedra* very likely originated in the Tethys coast during the late Cretaceous, and the South American *Ephedra* species have a single origin by dispersal from Mexico or North America. Our study highlights the importance of integrating phylogenomic and ecological approaches to address evolution of biological groups at the global scale.

## S.138.4 Sex chromosome evolution of Ginkgo biloba with implication for dioecy evolution of gymnosperms

Pan-Pan Bai¹, Kai-Jie Gu¹, Jun-Jie Wu¹, Yue Sun¹, Juan Xu¹, He Zhang², Guangyi Fan², Xuanmin Guang³, Huan Liu³, Yun-Peng Zhao

1 College of Life Sciences, Zhejiang University, China.
2 BGI-Qingdao, BGI-Shenzhen, Qingdao, China.
3 State Key Laboratory of Agricultural Genomics, BGI Research, Shenzhen, China

Sex determination genes of dioecy, which refers to male and female reproductive organs present in separate individuals, have been uncovered in a few angiosperms, while there is a contrasting gap in gymnosperms. Ginkgo biloba L., representing one of the five extant gymnosperm lineages, is a well-known dioecious tree species in which sex determination genes remain unknown. Here, anatomical observation, transcriptomic analyses, and evolutionary analyses strongly support that two B-class MADS-box genes at the non-recombination region of the Y chromosome acted as the sex determination genes of ginkgo. Functional transgenic analysis in Arabidopsis thaliana indicated that they were related to the male reproductive organ identity specification. Moreover, the spatial enhanced resolution omics sequencing (Stereo-seq) revealed that the highest expression level of the two sex determination genes were present in the male reproductive primordium, i.e., microsporophyll primordium, of male strobilus buds at the sex determination stage. Collectively, these results not only systemically verified the hypothesis that B-class MADS-box genes determine the sex of dioecy in gymno-
<figure><img src="image_326.png" /></figure>

sperms for the first time, but also pioneered the construction of the spatial transcriptome atlas of male strobilus buds in ginkgo. In light of the present discovery, we discussed the repeated evolution of dioecy and sex chromosomes in gymnosperm as well as its time course in seed plants.

## S.138.5 Reconstructing polyploid histories in Ephedra using target sequence capture

Stefanie M. Ickert-Bond¹, J. Gordon Burleigh²

1 UA Museum of the North Herbarium and Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, AK USA. 2 Department of Biology, University of Florida, Gainesville, USA

The gymnosperm genus *Ephedra* (Gnetales) is widely distributed in New and Old World arid and subtropical regions and has featured prominently in elucidating the phylogenetic interrelationships of seed plants. Reconstructing the evolutionary history of *Ephedra* has been hampered by fast rates of molecular evolution and extensive polyploidization, with 80% of the c. 54 species known to be polyploids, mostly tetraploids of allopolyploid origin. Recent advances in generating large sequencing datasets and new methodological advances for inferring complex histories from genomic data provide new promise for resolving previously intractable phylogenetic problems. Here we used target sequence capture data, generated using the GoFlag 408 flagellate land plant probe set, to infer the evolutionary history across 139 samples representing nearly all species of *Ephedra*. We discuss some of the challenges of using target capture data for *Ephedra*, and explore the value of assembling off-target plastid loci and new methods for phasing polyploid taxa using short read sequences and network inference on our ability to infer the reticulate history of *Ephedra* and identify putative progenitors of polyploid species. While numerous questions about the evolution of *Ephedra* remain, our analyses using targeted capture data and comprehensive sampling across the genus present new insights into the complex history of *Ephedra* as well as the challenges that remain.

## S.138.6 Perspectives on a comprehensive gymnosperm phylogeny from targeted enrichment sequencing

J. Gordon Burleigh¹, Lorena Endara², Stefanie M. Ickert-Bond³

1 Department of Biology, University of Florida, Gainesville, FL, USA. 2 Department of Biological Sciences, Clemson University, Clemson, SC, USA. 3 UA Museum of the North Herbarium and Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, AK, USA

The gymnosperms represent one of the two major lineages of seed plants and are critically important to the biodiversity of many ecosystems. While decades of molecular phylogenetic analyses have resolved many relationships within extant gymnosperms (c. 1080 species), some parts of the tree remain contentious, and there is a need for a comprehensive resource that highlights the complexities of evolution that can be illuminated with genomic data. We generated a phylogenomic dataset using targeted enrichment with the GoFlag 408 flagellate plant probe set, which covers 408 exons from 229 single or low copy nuclear genes, and sampled approximately 1060 taxa, representing all families and genera, and approximately 95% of all extant species. The resulting phylogeny is strongly supported, although some areas of the tree have weaker support and/or high levels of intragenomic conflict. Our analyses also highlight some of the challenges and limitations of targeted enrichment data from a universal probe set. We compare the tree inferred from targeted enrichment data with trees from plastid and transcriptome data. The targeted capture dataset provides new perspectives on some classic questions in gymnosperm phylogenetics and highlights areas where further research is needed, and it provides a resource of comparable and combinable data that can help illuminate future studies of evolutionary processes across the gymnosperms.
# S.139 GLOBAL CHANGE AND EVOLUTIONARY ADAPTATION OF PLANTS IN COASTAL AREAS

## S.139.1 Evolution and patterns of epimutation rates in stress

Chuangchao Zhou¹, Yushuai Wang¹, Yalan Wang¹, Cai Li¹, Tian Tang¹

1 State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, China

DNA methylation plays an important role in plant response to environmental stress whereas its contribution to long-term adaptation remains elusive. Here we estimate evolutionary rates of methylation gain and loss in mangroves and the potential role of natural selection using population epigenomic analysis. Mangroves exhibit a high ratio of gain over loss of CG methylation. Cytosine sites in CG context, particularly in the promoter regions, are under significant selection to remain methylated in mangroves but not in non-mangroves. We also analyzed available expression profiling data of mangroves and found that gains of CG DNA methylation in both promoter and coding regions are associated with reduced expression variation in stress. Our results suggest that DNA methylation is favored by selection in plants under stress adaptation, perhaps due to its impact on maintaining transcriptional homeostasis.

## S.139.2 Peripatric speciation of pantropical coastal plants in East Asia

Koji Takayama¹

1 Department of Botany, Kyoto University, Japan

Pantropical plants with sea-drifted seeds (PPSS) expanded globally through long-distance seed dispersal by sea. These plants, representing individual species or closely related species, thrive globally in tropical littoral areas. Notable examples include *Ipomoea pes-caprae* subsp. *brasiliensis* (Convolvulaceae), *Canavalia rosea* (Leguminosae), and *Hibiscus tiliaceus* (Malvaceae). Closely related species are found in marginal areas of

PPSS distribution, such as *Ipomoea pes-caprae* subsp. *per-caprae* (northern Indian Oceanic region), *Canavalia* subgenus *Maunaloa* (Hawaiian Islands), and *Hibiscus hamabo* (temperate East Asia) and *H. glaber* (Bonin Islands). Despite PPSS's extensive distribution, the species cohesion breaks down in peripatric areas due to limited gene flow, fostering differentiation through alternative allele fixation, local adaptation, and genetic drift. However, the spatiotemporal processes of peripatric speciation in PPSS remain unclear. To address this gap, we conducted phylogenomic analyses using plastome and genome-wide nuclear SNP data of *H. tiliaceus* and its East Asian relatives *H. hamabo* and *H. glaber*. Our dated phylogeny suggests that global expansion began around four million years ago, and species diversification began approximately one million years ago. Plastome phylogeny revealed that *H. hamabo* haplotypes were fully nested within *H. tiliaceus* haplotypes, supporting a peripatric speciation process involving migration to temperate zones. In contrast, *H. glaber* haplotypes showed diversification at the basal position in the plastome phylogeny. Genome-wide nuclear SNP phylogenies highlight distinct genetic segregations among species and geographical regions. *Hibiscus hamabo* exhibited low genetic diversity, whereas *H. glaber* displayed relatively high genetic diversity in both plastome and genome-wide SNPs. This study provides insights into the divergent genetic backgrounds of *H. hamabo* and *H. glaber*, both of which are undergoing peripatric speciation in East Asia. Discussions will focus on the factors contributing to these distinct genetic patterns in these peripatrically derived species.

## S.139.3 Assessing the conservation of terrestrial HCs in the Alboran Sea: Coast of Málaga and Granada

Goncalves Estefany¹, Javier García
Caballero¹, Federico Casimiro-Soriguer¹,
Hidalgo-Triana Noelia¹

1 Department of Botany and Plant Physiology (Botany Area), University of Málaga, Málaga, Spain; fs-origuer@uma.es
<figure><img src="image_327.png" /></figure>

The coastal regions of the Alboran Sea in southern Spain, bathed by the Mediterranean Sea, are celebrated for their remarkable biodiversity and contain several Habitats of Community Interest (HCI), a designation under the European Union Council Directive. Although those HCs host various ecosystems and numerous endemic species whose conservation is the shared responsibility of EU member states, many of them face significant risks. In our study, we analysed the degree of conservation (DC) of terrestrial habitats along the coasts of Málaga and Granada, in order to provide key information for prioritising conservation measures. To that end, vegetation inventories were conducted to assess the DC of HCs, current coverage, the presence of typical species from a phytosociological perspective, and the invasion of non-native species. Our findings suggest that HCI Groups 1 and 2 (i.e., 1150, 1210, 1240, and 2210), including dunes, halonitrophilous vegetation, and cliffs, were the most impacted due to displaying diminished plant coverage and a proliferation of invasive species. Enhanced management is therefore urgently needed to ensure the preservation and protection of those unique ecosystems. We also propose that the comprehensive evaluation method used in our study and the creation of a conservation index have the potential for extrapolation to other HCs across Europe.

## S.139.4 Genomic evidence for rediploidization and adaptive evolution following the whole-genome triplication

Xiao Feng¹, Qipian Chen¹,², Weihong Wu¹, Jiexin Wang¹, Guohong Li¹, Shaohua Xu¹, Shao Shao¹, Min Liu¹, Cairong Zhong³, Chung-I Wu¹, Suhua Shi¹, Ziwen He¹

1 School of Life Sciences, Sun Yat-sen University, Guangzhou, China. 2 Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China. 3 Hainan Academy of Forestry (Hainan Academy of Mangrove), Haikou, China

Whole-genome duplication (WGD), or polyploidy, events are widespread and significant in the evolutionary history of angiosperms. However, empirical evidence for rediploidization, the major process where polyploids give rise to diploid descendants, is still lacking at the genomic level. Here we present chromosome-scale genomes of the mangrove tree *Sonneratia alba* and the related inland plant *Lagerstroemia speciosa*.

Their common ancestor has experienced a whole-genome triplication (WGT) approximately 64 Mya coinciding with a period of dramatic global climate change. *Sonneratia*, adapting mangrove habitats, experienced extensive chromosome rearrangements post-WGT. We observe the WGT retentions display sequence and expression divergence, suggesting potential neo- and subfunctionalization. Strong selection acting on three-copy retentions indicates adaptive value in response to new environments. To elucidate the role of ploidy changes in genome evolution, we improve a model of the polyploidization-rediploidization process based on genetic evidence, contributing to the understanding of adaptive evolution during climate change.

## S.139.5 Ecology and evolution of invasive salt marsh grass *Spartina alterniflora*

Wenwen Liu¹, Yihui Zhang¹

1 Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, China

Coastal saltmarsh wetlands provide high levels of ecosystem services. Many of these services stem from the vegetation of coastal saltmarsh systems. However, global change has posed a serious threat to coastal salt marshes in recent years. Therefore, it is critical to determine the spatio-temporal patterns, ecological processes and adaptation mechanisms of coastal saltmarsh vegetation. In this study, the global invasive salt marsh plant *Spartina alterniflora* was taken as the model salt marsh plant, and studied at the individual, population, and community levels. In particular, we studied the spatial and temporal dynamics, ecological processes and adaptation mechanisms of different levels of vegetation in coastal saltmarshes in response to multi-scale environmental gradients. Our study identified three key findings: 1) we clarified that the spatio-temporal allometric patterns in *S. alterniflora* followed self-thinning and life-history theory, suggesting that salt marsh plants may serve as simple, model systems for studies of plant life history. 2) Intraspecific hybridization and rapid evolution drive different latitudinal clines in *S. alterniflora* in the native and introduced ranges, indicating the importance of phenotypic plasticity and genetic control of
<figure><img src="image_328.png" /></figure>

change during the invasion process. 3) Community composition, distance, and latitude alter the synchrony and stability of *S. alterniflora* biomass, suggesting that managers should identify the most sensitive habitat to abiotic variation as a priority for monitoring. In summary, the above multi-level and multi-scale studies clarified the pattern, process, and mechanism of coastal salt marsh wetlands, and provided new methods, perspectives, and ideas for establishing salt marsh model system, understanding its ecological service value, and protecting habitat and species diversity. Furthermore, it also provides decision support for the adaptive scientific management of coastal wetlands under global change.

## S.139.6 Leaf pattern in Colombian Caribbean mangroves

Mary L. Berdugo-Lattke¹,², J. Orlando Rangel-Ch²

1 Grupo de investigación de agua y desarrollo sostenible, Semillero Tygua, Programa de Biología, Facultad de Ingeniería y Ciencias Básicas, Universidad Central, Bogotá, Colombia. 2 Grupo de investigación de biodiversidad y conservación, Instituto de Ciencias Naturales, Universidad Nacional de Colombia, Bogotá, Colombia

The biotypological foliar pattern was characterized in the mangrove vegetation (39 inventories or surveys) of the Caribbean region of Colombia, in localities of the departments La Guajira (arid), Magdalena (semiarid), Sucre (semihumid), Córdoba (humid),

defined by three phytosociological formations or alliances: Lagunculario racemosae - Avicennion germinantis especially the association Avicennion germinantis-Rhizophoretum manglis (Magdalena, Sucre); Lagunculario racemosae-Rhizophorion manglis with the association Lagunculario racemosae-Conocarpodetum erecti (La Guajira, Magdalena P. N.N. Tayrona) and Fico dendrocidae - Rhizophorion manglis especially the association Priorio copaiferae-Rhizophoretum manglis (Córdoba). Between 5 to 20 leaves and one branch fragment were collected per survey to estimate leaf area (cm²), specific weight (gr/dm²), succulence (gr/dm²), dry mass (%), thickness (mm) and wood density (gr/ml). A total of 812 samples were processed, from 14 families, 19 genera and 21 species. The general pattern corresponds to simple, notophyll leaves (31-53 cm²), with elliptic and oblong shapes, entire margin, obtuse apex and base, coriaceous consistency, unprotected and lamina thickness B (0.16-0.35mm). As the aridity condition increases (arid and semi-arid zones La Guajira, Tayrona N.N.P.), there is a tendency to increase the values of specific weight and succulence (gr/dm²), dry mass (%), leaf thickness (mm) and wood density (gr/ml), conditions that are related to higher salinity. Leaf area increases in the semi-humid and humid zones (moderate relationship with precipitation, R² = 0.62**), a condition associated with lower salinity and/or greater influence of continental water. The results illustrate the differential responses related to the type of mangrove vegetation (floristic composition and structure-architecture aspects), furthermore the strategies species for to control salinity regulation and transpiration.

## S.140 IAPT EARLY CAREER INVESTIGATOR SYMPOSIUM: THE EDGE OF THE UNKNOWN IN PLANT, ALGAE, AND FUNGAL SYSTEMATICS. SESSION 1

### S.140.1 The rapid radiation of Bomarea (Alstroemeriaceae: Liliales), driven by the rise of the Andes

Carrie M. Tribble¹,², Fernando Alzate-Guarín³, Etelvina Gándara⁴, Araz Vartoumian¹,⁵, J. Gordon Burleigh⁶, Rosana Zenil-Ferguson⁷, Chelsea D. Specht⁸, and Carl J. Rothfels²,⁹
<figure><img src="image_329.png" /></figure>

1 School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, USA. 2 University Herbarium and Department of Integrative Biology University of California, Berkeley, USA. 3 Grupo de Estudios Botánicos and Herbario Universidad de Antioquia, Instituto de Biología, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia, Medellín, Colombia. 4 Facultad de Ciencias Biológicas, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico. 5 Department of Oral Biology, University of California, Los Angeles, USA. 6 Department of Biology, University of Florida, Gainesville, FL USA. 7 Department of Biology, University of Kentucky, Lexington KY USA. 8 Section of Plant Biology and the L.H. Bailey Hortorium, School of Integrative Plant Science, Cornell University, Ithaca, USA. 9 Intermountain Herbarium, Department of Biology, and Ecology Center, Utah State University, Logan, USA

Geological events such as mountain uplift affect how, when, and where species diversify, but measuring those effects is a longstanding challenge. Andean orogeny impacted the evolution of regional biota by creating barriers to gene flow, opening new habitats, and changing local climate. *Bomarea* (Alstroemeriaceae) are tropical plants with (often) small, isolated ranges; in total, *Bomarea* species occur from central Mexico to central Chile. This genus appears to have evolved rapidly and quite recently, and rapid radiations are often challenging to resolve with traditional phylogenetic inference. In this study, we apply phylogenomics—with hundreds of loci, gene-tree-based data curation, and a multispecies-coalescent approach—to infer the phylogeny of *Bomarea*. We used this phylogeny to untangle the potential drivers of diversification and biogeographic history. In particular, we test if Andean orogeny contributed to the diversification of *Bomarea*. We find that *Bomarea* originated in the central Andes during the mid-Miocene, then spread north, following the trajectory of mountain uplift. Furthermore, Andean lineages diversified faster than non-Andean relatives. *Bomarea* thus demonstrates that—at least in some cases—geological change rather than environmental stability has driven high species diversity in a tropical biodiversity hotspot. These results also demonstrate the utility (and danger) of genome-scale data for making macroevolutionary inferences.

### S.140.2 On the origin and complex convergent evolution of fleshy cones in Podocarpaceae

Raees Khan¹,²,³, Robert S. Hill¹, Jie Liu²,³

1 School of Biological Sciences, The University of Adelaide, Adelaide, SA, Australia. 2 CAS Key Laboratory

for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China. 3Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China

Conifers are economically and ecologically important and form extensive forests in both the Southern and Northern Hemispheres. The Podocarpaceae have evolved distinctive seed cones, most of which are fleshy. The detailed diversity and evolution of seed cones is poorly known in this family. We undertook a comparative analysis of Podocarpaceae seed cone morpho-anatomical traits and used ancestral state reconstruction to interpret their evolution. The family exhibits great diversity in functional structures and five distinct structures (free epimatum, fused epimatum, fleshy bracts, arils, and the receptaculum) are involved in the formation of their fleshy cones. Each of these structures has distinct evolutionary patterns, involving multiple origins and/or losses of fleshiness, with a minimum of 24 independent evolutionary changes either from non-fleshy to fleshy or fleshy to non-fleshy structures. The pathways of fleshy seed cone production vary among genera and sometimes within a genus. The Podocarpaceae show great evolutionary lability in seed cone morphology and especially in the production of fleshy seed cones, which are associated with the pollination mechanism (by assisting ovule inversion), protection of the ovule/ seed and seed dispersal. The reconstruction of the ancestral Podocarpaceae seed cone is complicated by extinction, convergent evolution, and the relatively few fossil seed cone records.

### S.140.3 Pteridophyte Phylogeny Group II and beyond: an updated, community-driven, and open classification for ferns and lycophytes

Joel H. Nitta¹, Carl J. Rothfels², Harald Schneider³, Eric Schuettpelz⁴

1 Graduate School of Global and Transdisciplinary Studies, Chiba University, Chiba, Japan. 2 Ecology Center and Department of Biology, Utah State University, Logan, UT, USA. 3 Center for Integrative Conservation, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, China. 4 Department of Botany, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA
<figure><img src="image_330.png" /></figure>

We live in an era of big data, when no single person can manually digest all the information required to make optimal decisions. This fact extends to the field of systematic biology, which is being revolutionized by rapid improvements in genomic sequencing and phylogenetic analysis. One approach to handling this data deluge is to move beyond the traditional system whereby a single "expert" publishes their view on the most logical taxonomic system for a particular group, to one where a community of scientists work collaboratively to reach taxonomic decisions. This approach was successfully applied to ferns and lyophytes by the Pteridophyte Phylogeny Group (PPG) in 2016, resulting in the landmark PPG I classification. Since then, systematic research has continued apace, resulting in a need to update PPG I. Here, we report on the methodologies and progress to date of PPG II, with a focus on how such a community-driven, open approach to taxonomy can be employed by systematists studying other groups. In particular, in formulating PPG II we utilize GitHub as an open online platform to solicit and discuss taxonomic proposals and then, with the assistance of custom, open-source R scripts, to adopt those proposals, ensuring that taxonomic interdependencies are fully accounted for (see https://pteridogroup.github.io/).

## S.140.4 Integrative taxon-omics and deep learning in Ranunculus

Lara M. Kösters¹, Kevin Karbstein¹, Martin Hofmann², Ladislav Hodač¹, Patrick Mäder²,³,⁴, Jana Wäldchen¹,³

1 Biogeochemical Integration, Max-Planck-Institute for Biogeochemistry, Jena, Germany. 2 Data-intensive Systems and Visualization Group, Technical University, Ilmenau, Germany. 3 German Centre for Integrative Biodiversity Research, Halle-Jena-Leipzig, Leipzig, Germany. 4 Faculty of Biological Sciences, Friedrich Schiller University, Jena, Germany

Integrative taxon-omics aims to combine genomics with a multitude of different complementary datasets such as morphology, ploidy level, information on hybridization and/or apomixis, geography, or ecology. Here, the goal is to advance species delimitation and to achieve a more reliable species classification. Machine learning (ML) encompasses a range of methods that autonomously learn to map a given input to a desired output. ML is rapidly gaining attention in the biological and botanical community for its ability to

process highly multi-dimensional, large-scale datasets. However, there have been few attempts so far to combine an integrative approach with ML methodologies. We explore the potential of ML to classify species in the highly reticulate evolving Ranunculus auricomus complex, in which taxonomically challenging processes such as apomixis, hybridization, and polyploidy are prevalent. In our previous work, we assessed different fusion techniques with the integration of morphological data and genetic markers using convolutional neural networks (CNNs) that now serve as a basis for the fusion of extensive genetic data, morphology, ecology, and ploidy as well as reproductive information. We show that an integrative approach in ML species classification is not only feasible but that it increases the performance of the neural network. We hope to encourage a more holistic perspective of future ML models.

## S.140.5 Epiphyllous fungi from Early Cretaceous swamp forests: exploring multiple techniques for recovering fungal remains from lignites

Giovanni C. Nunes¹, Louise Egerton-Warburton², Patrick S. Herendeen², Niiden Ichinnorov³, Gongle Shi⁴, Peter R. Crane⁵,⁶, Fabiany Herrera⁷

1 Egidio Feruglio Paleontological Museum, Trelew, Argentina. 2 Chicago Botanic Garden, Chicago, IL, USA. 3 Institute of Paleontology, Mongolian Academy of Sciences, Ulaanbaatar-15160, Mongolia. 4 State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Palaeoenvironment, Chinese Academy of Sciences, Nanjing, China. 5 School of Forestry and Environmental Studies, Yale University, New Haven, USA. 6 Oak Spring Garden Foundation, Oak Spring, Upperville, Virginia, USA. 7 Earth Sciences, Negaunee Integrative Research Center, Field Museum of Natural History, Chicago, IL, USA

A preliminary report of fungal remains associated with leaves of different gymnosperm taxa is presented in this study. The fossils were recovered from lignites collected at the Early Cretaceous Tevshiingovi Formation (~120 Ma – Aptian-Albian) in Central Mongolia. This contribution also explores the different techniques used for recovering the fungal remains from the lig-
<figure><img src="image_331.png" /></figure>

nites. Around 450 specimens of leaves of several gymnosperm lineages (i.e., ginkgophytes, corystosperms, conifers) were analyzed using multiple complementary techniques (i.e., light microscopy, epifluorescence, SEM, and X-ray computer microtomography). For observations under light microscopy, most of the samples were previously bleached, applying a modified protocol for chemical treatment of fossil cuticles (with both H₂O₂ and KOH). Staining of the fungal remains with different stains (e.g., safranin, cotton blue, congo red) for enhancing critical features was also explored. Abundant nonreproductive and reproductive remains of epiphyllous fungi are associated with the cuticular surface of around 70% of the specimens. The most conspicuous and abundant structures are scattered to densely distributed thyriothecium-like ascomata, which are mostly associated with the leaves of ginkgophytes and corystosperms. Additional remains include septate hyphae, often with appressoria, 1-3 septate phragmospores, scolecospores, and perithecia with associated filamentous mycelium. These fungal remains are attributable to epiphyllous, probably saprobic, fungi within different lineages of Ascomycota (e.g., Dothideomycetes, Sordariomycetes) and other *incertae sedis* taxa. This report represents the first steps in documenting the fungal diversity associated with the leaves of gymnosperms and in the characterization of the ecological relationships between different organisms from the Early Cretaceous swamp forests of Mongolia. Exploring different complementary techniques demonstrates an improvement in recovering fungal remains from lignite samples. More importantly, the abundance and well preservation of the fossil fungi will help recognize different developmental structures and features of the epiphyllous community.

## S.140.6 Bryophytes of the high mountains of Madagascar: a comparative analysis of diversity and distribution patterns

Lovanomenjanahary Marline¹,²,³,

Rivoharifara Randrianarimanana²,⁴, Rhian

Smith¹, Alexandre Antonelli¹,⁵,⁶,⁷

1 Royal Botanic Gardens, Kew, Richmond, UK. 2 Kew Madagascar Conservation Centre, Antananarivo, Madagascar. 3 Association Vahatra, Antananarivo, Madagascar. 4 Mention Biologie et Ecologie Végétales, Université d'Antananarivo, Antananarivo, Madagascar. 5 Gothenburg Global Biodiversity

Centre, Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden. 6 Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China. 7 Department of Biology, University of Oxford, Oxford, UK

Madagascar is a global biodiversity hotspot, with some of the highest levels of diversity and endemism on the planet. Its high mountain massifs are remarkable for having a higher degree of regional endemism, often localized to an individual massif. Madagascar's exceptional biodiversity has motivated many studies; however, they have not been evenly distributed and many groups of organisms remain poorly studied. Bryophytes are among the least documented of the Malagasy biodiversity. We conducted detailed analyses of bryophyte communities along elevational gradients in three high mountains in Madagascar to describe the hidden but important biodiversity of bryophyte and understand bryophyte community structure along elevational gradients. We explored Tsaratanana Integral reserve, North-western Madagascar (2888m), Andohahela national park, South-eastern Madagascar (1956m) and Marojejy National Park North-eastern Madagascar (2130m). Preliminary observation shows a diverse and abundant community of bryophytes. Overall, species richness is exhibiting a hump-shaped pattern along elevation gradients, peaking at mid-elevation. Preliminary analyses of the bryophyte community indicate that most species have a narrow range of elevational distribution and are specialized to a particular microhabitat. At higher taxonomic rank, many genera and families also have a narrow range of elevational distribution and microhabitat preferences. This implies that microhabitat preferences are taxonomically structured. This investigation constitutes a significant biodiversity resource that will be used in a range of contexts such as taxonomic revision of the many understudied and likely to be misidentified group of bryophytes. And given that there are no existing molecular databases on the bryophytes of Madagascar, new bryophytes collections from those unique sites have been considered for molecular analysis, especially leveraging next-generation sequencing technologies.
# S.141 TRANSPOSON TAKEOVER: TRANSPOSABLE ELMENTS IN PLANT GENOME EVOLUTION, ADAPTATION AND REGULATION

## S.141.1 Transposon dynamics in plant genomes

Josep M.Casacuberta¹, Lucía Campos¹, Rauú Castanera¹, Noemia Morales-Díaz¹, Marc Pulido¹, Carlos Vicient¹

1 CRAG (CSIC-IRTA-UAB-UB), Barcelona, Spain

Transposable Elements (TEs) are major components of eukaryote genomes and in particular of that of plants. The relationship between TEs and the host genome is often seen as a conflict with genomes tightly controlling TEs which transiently escape control by horizontal transfer or during stress situations, producing bursts of transposition and amplification, until the genome establishes the control and silence them. However, the dynamics of TEs is highly diverse and depends on the type and family of the TEs and the genome they inhabit. In our laboratory we are studying the dynamics of TEs in a wide range of plant genomes including rice, almond and peach, cotton, and *P. patens*. In this communication I present recent data illustrating different strategies followed by plant TEs to be maintained in the genome ecosystem. On the other hand, the long lasting presence of TEs in genomes has endowed the latter with a high plasticity during evolution. Our laboratory, among many others, has shown that TEs have generated genome variability linked to phenotype diversity selected during plant domestication and breeding. In particular, our recent data points to an important role of TE in generating subtle transcriptional variability of transcription factors and regulatory proteins, that has been selected accompanying domestication and local adaptation of crops. In this communication I also show recent data on the capacity of TEs to generate phenotypic diversity selected during crop domestication and local adaptation.

## S.141.2 Dynamics of centromeric retrotransposons and their consequences for chromosomal evolution

Manuel Poretti¹, Rimjhim Choudhury¹, Yile Huang², Hussein Anani², Terezie Mandáková², Martin Lysák² and Christian Parisod¹

1 Department of Biology, University of Fribourg, Fribourg, Switzerland. 2 CEITEC Masaryk University, Brno, Czech Republic

Beyond their fundamental importance for the segregation of chromosomes, centromeres and their evolution remain elusive. In plants, flanking (pericentromeric) segments are characterized by low recombination and chiefly constituted of gypsy retrotransposons. Although such distribution expectedly results from an equilibrium between the insertion of new copies and their removal by purifying selection in high-recombining segments away from the centromere, empirical evidence remains scarce. Chromosome-scale assemblies characterizing the gene space and repetitive fraction of three diploids within the highly-polymorphic species *Biscutella leavigata* and one outgroup species were used to assess the evolution of retrotransposons around centromeres. Despite high synteny within the species, we find large variability in the non-coding part of the genome and particularly high sequence turnover among pericentromeric segments of the genome from the smallest population. By comparing retrotransposons actively targeting pericentromeric regions such as CRM elements to similarly-distributed retrotransposons that are unknown to present biased insertion such as ATHILA elements, we infer their dynamics of transposition vs deletion and highlight the role of specialized retrotransposons during a centromere shift. We further show that they disperse towards the distal part of nucleolar chromosomes and
invade intervening gene-rich regions, increasing the methylation of nearby gene and decreasing their expression. Accordingly, bursts of retrotransposon activity associated with the rapid evolution of centromeres are not only affecting the formation and maintenance of heterochromatin and chromocenters, but also result in considerable changes across the gene space.

### S.141.3 Repeat turnover meets stable chromosomes: repetitive DNA sequences mark speciation and gene pool boundaries in beets

Nicola Schmidt¹, Katharina Sielemann²,³, Sarah Breitenbach¹, Jörg Fuchs⁴, Boas Pucker⁵, Bernd Weisshaar², Daniela Holtgräwe², Tony Heitkam¹,⁶

¹Faculty of Biology, Technische Universität Dresden, Dresden, Germany. ²Genetics and Genomics of Plants, Center for Biotechnology & Faculty of Biology, Bielefeld University, Bielefeld, Germany. ³Graduate School DILS, Bielefeld Institute for Bioinformatics Infrastructure, Bielefeld University, Bielefeld, Germany. ⁴Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Stadt Seeland, Germany. ⁵Plant Biotechnology and Bioinformatics, Institute of Plant Biology & Braunschweig Integrated Centre of Systems Biology, TU Braunschweig, Braunschweig, Germany. ⁶Institute of Biology, NAWI Graz, Karl-Franzens-Universität, Graz, Austria

Sugar beet and its wild relatives share a base chromosome number of nine and similar chromosome morphologies. Yet, interspecific breeding is impeded by chromosome and sequence divergence that is still not fully understood. Since repetitive DNAs are among the fastest evolving parts of the genome, we investigated, if repeatome innovations and losses are linked to chromosomal differentiation and speciation. We traced genome and chromosome-wide evolution across thirteen beet species comprising all sections of the genera *Beta* and *Patellifolia*. For this, we combined short and long read sequencing, flow cytometry, and cytogenetics to build a comprehensive framework that spans the complete scale from DNA to chromosome to genome. Genome sizes and repeat profiles reflect the separation into three gene pools with contrasting evolutionary patterns. Among all repeats, satellite DNAs harbor most genetic variability, leading to fundamentally differ-

ent centromere architectures, ranging from chromosomal uniformity in *Beta* and *Patellifolia* to the formation of patchwork chromosomes in *Coriolinae/Nanae*. We show that repetitive DNAs are causal for the genome expansions and contractions across the beet genera, providing insights into the genomic underpinnings of beet speciation. Satellite DNAs in particular vary considerably between beet genomes, leading to the evolution of distinct chromosomal setups in the three gene pools, likely contributing to the barriers in beet breeding. Thus, with their isokaryotypic chromosome sets, beet genomes present an ideal system for studying the link between repeats, genomic variability, and chromosomal differentiation and provide a theoretical fundament for understanding barriers in any crop breeding effort.

### S.141.4 Role of transposable elements in the domestication of fruit trees: insights from the apple trees

Cornille, A.¹, Venon, A.¹, Chen X.¹, Mesnil, A.¹, Bourgeois Y.², Marrande W.³, Confais J.⁴, Alix K.¹

¹ Université Paris Saclay, INRAE, CNRS, AgroParisTech, GQE - Le Moulon, Gif-sur-Yvette, France. ² DIADE, University of Montpellier, CIRAD, IRD, Montpellier, France. ³ French Plant Genetic Resource Center, INRAE-CNRGV, Castanet Tososan, France. ⁴ Université Paris-Saclay, INRAE, URGI, Versailles, France

Transposable elements (TEs) are major components of eukaryotic genomes and are supposed to be evolutionary catalyzers. Unlike the extensive information available for annual crops, the role of TEs in the adaptation of perennial crops, such as fruit trees, has been studied in less depth. Yet, the domestication of perennials is expected to follow different processes than annuals, with distinct genetic outcomes. I present results on TE copy number variation and TE polymorphism insertions in crop-wild population pairs of the apple trees based on the joint study of SNPs and TEs and ongoing experiments. This research will add to our understanding of the role of TEs in the evolution of genetic diversity and innovation in perennials and, ultimately, in the adaptation of populations to recent environmental changes, together with the applied consequences of the findings.
### S.141.5 Endogenous pararetroviruses (EPRVs): their evolution, diversity, and regulation

Trude Schwarzacher¹, Katja R. Richert-Poeggeler², Osamah Alisaw³, Gilbert Chofong², Kitty Vijverberg⁴, Pat Heslop-Harrison¹

¹Department of Genetics and Genome Biology, Institute for Environmental Futures, University of Leicester, Leicester, UK. 2 Julius Kuehn Institute, Federal Research Centre for Cultivated Plants, Institute for Epidemiology and Pathogen Diagnostics, Braunschweig, Germany. 3 Department of Plant Protection, Faculty of Agriculture, University of Kufa, Kufa, Iraq. 4 Radboud University, Institute for Water and Wetland Research (IWWR), Nijmegen, Netherlands

Pararetroviruses (PRVs) share a common origin with retroviruses and LTR retrotransposons employing reverse transcription for genome replication. In plants, both episomal and chromosomal (endogenous; EPRVs) forms are present. Pararetrovirus evolution most likely occurred through recombination of an ancestral genomic retroelement with exogenous RNA viruses and resulted in horizontal gene transfer. Illegitimate recombination probably also facilitated pararetrovirus integration into the host genomes using virus sequences instead of homologous host genomic sequences on the sister chromatid (during mitosis) or homologous chromosome (during meiosis). RNA interference initiated in the host, regulates episomal and chromosomal pararetrovirus forms, while pararetroviruses themselves have evolved suppressors against this plant defense. Analysing genome and raw read sequences as well as small (sm)RNA databases revealed three types of EPRV clusters comprising petuvirus-, florendovirus- and caulimovirus-like sequences along with two distinct variants of Petunia vein clearing virus (ePVCV-1 and -2) in wild and hybrid petunia. Both ePVCV variants increased in copy number in *P. hybrida*, a diploid hybrid of *P. axillaris* and *P. inflata*, while exhibiting differences in sequences, organization and activity patterns. ePVCV-1 shared 99% sequence identity with the known episomal PVCV and host smRNAs mapped throughout its genome, likely serving as template for initiating episomal PVCV replication in *P. hybrida*. ePVCV-2, with only 74% similarity, lacked some regulatory elements and homologous smRNAs, rendering it replication incompetent. In the permissive genomes *P. axillaris* and *P. hybrida*, we found

the pericentromeric regions to be hot spots for EPRV integration. In PVCV infected *P. parodii*, with no detectable ePVCV but episomally replicating PVCV, *de novo* integration of PVCV in the telomeric regions of a single chromosome was identified. We postulate that the pericentromeric insertions are older and silenced while telomeric ePVCV localizations of some *P. hybrida* lines indicate recent, transient activation of ePVCV-1 and *de novo* integration.

### S.141.6 What is the contribution of transposable elements to adaptive evolution? A case study using the Persimmon genus Diospyros

Katie Emelianova¹, Teerna Saugata Khastgir¹, Jérôme Munzinger², Ovidiu Paun¹

¹Department of Botany and Biodiversity Research, Faculty of Life Sciences, University of Vienna, Vienna, Austria. 2 AMAP, IRD, CIRAD, CNRS, INRA, Université Montpellier, Montpellier, France

New Caledonia, a biodiversity hotspot with a mosaic of altitudinal, climatic and edaphic environments, was colonized by the Persimmon genus *Diospyros* four times. While three of the New Caledonian *Diospyros* clades have few species, one clade underwent an explosive burst of speciation over a period of ca. 1000 generations, today numbering over 30 species which have repeatedly colonized almost all habitat types on the peninsula. The genome sizes of the radiating clade are roughly double that of their non-radiating counterparts, driven largely by transposable element (TE) expansion rather than polyploidy, prompting speculation that transposable element dynamics underlie the success of the radiating clade through rapid generation of genetic diversity, ameliorating the founder effects which often follow long distance dispersal events. To investigate the origins of the adaptive variation required for *Diospyros* to so successfully colonize New Caledonia, we ask how TE dynamics may have contributed to the adaptive potential of radiating *Diospyros* species. Using long read PacBio sequencing data, we compare the TE landscapes of adaptively radiating *Diospyros* species to an outgroup of the radiation, asking which TE families have undergone expansion, when expansion occurred, and whether repetitive
<figure><img src="image_332.png" /></figure>

element proliferation pre-dated the burst of spe-
ciation in New Caledonian *Diospyros* or occurred
after dispersal to the archipelago. By analysing the
TE landscape of adaptively radiating and outgroup

species within a comparative genomic framework,
we can begin to answer questions about the inter-
play of the mobile genome, shifting ecological cir-
cumstances, and the drivers of biodiversity.

**S.142 PLANT RESPONSES TO STRESSES AND CLIMATE CHANGE. SESSION 6**

S.142.1 Integrating functional
traits for predicting the
response of flowering
phenology to change in
a diverse Mediterranean
community

Daniel Pareja-Bonilla¹, Montserrat Arista¹,
Leonor P, Cerdeira-Morellato², Pedro L. Ortiz¹

1 Departamento de Biología Vegetal y Ecología,
Universidad de Sevilla, Sevilla, Spain. 2 Instituto de
Biociencias, Universidade Estadual Paulista "Júlio
de Mesquita Filho", Rio Claro (SP), Brazil

Flowering time plays a key role in the reproductive success of plants. It is subject to natural selection and we now know that climate change is shifting flowering phenologies in the Northern Hemisphere, favouring early flowering. However, due to the scarcity of studies of natural communities with long data series, the traits involved in the response of flowering time to climate change are poorly known, especially non-vegetative traits (reproductive, phenological and phylogenetic traits). In the Mediterranean region, the effects of climate change are stronger than the global average and there is an urgent need to understand how biodiversity will be affected in this area. In this study we investigated how the overall flowering phenology of a species-rich community comprising 270 plant species from the Southwest of the Iberian Peninsula has changed over the last 35 years (1980 and 2020 decades) in response to climate change, and how functional traits conditioned this change. We built models combining vegetative, reproductive and phenological traits (flowering season), as well as phylogenetic information as a covariant. Preliminary results indicate that the advance in the flowering date is generalised across the community and that flowering season plays a significant role in the response of flowering to climate change, with winter/early spring flowering

species showing a stronger phenological shift. Our
results show that mismatches resulting from chang-
es in the co-flowering neighbourhood may lead to
new competitive or facilitative interactions regarding
plant reproduction. This study will allow us to predict
the phenological response of Mediterranean com-
munities and the reassembly of species according
to functional traits, increasing our capacity to design
conservation strategies for natural areas in the face of
climate change.

S.142.2 Historical forest uses constrain tree growth responses to climate change: a case on resin tapped maritime pines (Pinus pinaster)

Cristopher Fernández-Blas¹, Paloma Ruiz-Benito¹, Antonio Gazol², Elena Granda¹, Eva Samblás¹, Irene Granado-Díaz¹, Patricia González-Díaz³, Miguel A. Zavala¹, C. Valeriano², J. Julio Camarero²

1 Universidad de Alcalá, Alcalá de Henares, Spain. 2 Instituto Pirenaico de Ecología, Consejo Superior de Investigaciones Científicas (CSIC), Zaragoza, Spain. 3 Centro de Investigaciones sobre Desertificación (CSIC-UV-GV), Valencia, Spain

Resin extraction from pine trees was an important eco-
nomic activity for most of the 20th century in forested
countries such as Spain. However, the decrease in resin
prices and massive rural migration to cities led to their
abandonment in the 1960s-1970s. Reduced tree growth
is often observed after long periods of resin tapping, but
it is unknown how these formerly tapped stands would
respond to recent climate warming and aridification. In
Spain, maritime pine (*Pinus pinaster*) was extensively
exploited for resin extraction in several regions subject-
ed to increasing drought stress. To understand the differential growth and their responses to climate between resin tapped and non-resin tapped trees, we sampled three historically tapped maritime pine stands in Teruel, eastern Spain, where tapping finished in the 1970s. We extracted and measured cores from 51 resin-tapped and 47 non-resin tapped trees, and compared their growth trends and responses to climate variables and a drought index. Basal area increment was used to measure annual growth. We performed linear mixed regression models to understand the differential responses of resin tapped and non-resin tapped trees to climate variables, including as covariates tree size, age and the resin tapped status. In the study area, climate has progressively warmer and dried since the 1970s. Tree growth was higher in resin tapped trees compared to non-resin tapped trees, which were generally younger. Formerly tapped trees responded more to drought severity than non-tapped trees and were also more negatively impacted by warmer summer temperature. Our results suggest that the legacy effects of previous management can constrain tree responses to climate change.

### S.142.3 Rate of phenology advance in boreal conifers in Canada

Diego S. Podadera¹,², Annie Deslauriers², Sergio Rossi², Lorena Balducci²

1 Department of Forest Science, Soils and Environment, São Paulo State University-UNESP, Botucatu, Brazil. 2 Département des Sciences Fondamentales, Université du Québec à Chicoutimi-UQAC, Chicoutimi, Canada

The emergence of buds marks a critical phase in the life cycle of plants, signifying an essential response to seasonal shifts in weather patterns. Within boreal forests, distinct species display unique phenological behaviors, and their responsiveness to warming conditions can vary significantly. This study focuses on examining the budburst timing across Canada within three coniferous species, Balsam fir (Abies balsamea), black spruce (Picea mariana), and white spruce (Picea glauca) (Pinaceae). Our study encompasses 2839 locations spanning from 1980 to 2021. Our analysis involved identifying the triggers for budburst, assessing its acceleration rate, and discerning the spatiotemporal patterns in relation to climate. We developed response functions between budburst and climate (air temperature, precipitation, and solar radiation), and used the strongest correlations to test their effect on budburst. Employing spa-

tially constrained multivariate clustering techniques, we discerned distinct budburst patterns across Canada territory. Our findings revealed a baseline disparity of 17 days between black spruce and balsam fir/white spruce budburst timings. Additionally, we observed a negative correlation between the mean minimum May temperature and budburst date. Black spruce exhibited a notable advancement in budburst at a rate of -3.33 days °C⁻¹, twice the rate of balsam fir and white spruce (-1.53 and -1.27 days °C⁻¹, respectively). Notably, the clustering of budburst timings corresponded closely with Canada's ecoprovince distribution, aligning with temperature gradients across the nation. May's mean minimum temperature emerged as the primary driver for budburst in northern tree species. Our projections suggest an earlier budburst in a warmer spring, with black spruce displaying the most pronounced rate of change. Intriguingly, the identified clustering patterns remained consistent despite the longitudinal precipitation gradient across Canada. This study underscores the intricate relationship between climate, geography, and the timing of budburst in boreal tree species.

### S.142.4 Molecular mechanisms of seed persistence during the extreme heat of a wildfire

Sarah J. McInnes¹, Ryan Tangney¹,², Mark K.J. Ooi¹

1 Centre for Ecosystem Science, School of Biological Earth and Environmental Sciences, University of New South Wales, Kensington, NSW, Australia. 2 Kings Park Science, Biodiversity, and Conservation Science, Department of Biodiversity, Conservation, and Attractions, Kings Park, WA, Australia

Fire is a key ecological driver and many plant species have evolved to persist in fire-prone regions. During fire, different life stages of plants, including seeds, are exposed to temperatures as high as 150°C, yet are able to persist. This suggests that molecular processes within the seed provide a mechanism for survival. In this study, we sought to understand the molecular aspects of seed persistence during the extreme heat of wildfire. We focused on Acacia pycnantha, a species native to fire-prone southeastern Australia, which has heat-triggered germination cues and recruits prolifically post-fire, and therefore has a life-cycle tightly linked with fire. We explored the physiology of Acacia pycnantha under heat stress through pairing molecular biology with traditional seed biology methods. To examine
<figure><img src="image_333.png" /></figure>

seed survival under extreme heat, we subjected seeds to 10-minute heat shock treatments ranging from 25°C to 150°C, and subsequently conducted germination trials. Seed water-content isotherms were constructed to determine seed hydration profiles post-heat stress, and mRNA extracted to create gene expression profiles. Gene expression was examined at different seed hydration levels after heating at the optimum temperature (92 °C) for dormancy-break to understand the mechanisms that support persistence during the extreme heat from fires. We report on the genes, and thus mechanisms, that are expressed during extreme temperatures and the role these may have in enabling species persistence. This work is essential for ecological understanding and informing conservation efforts as fire regimes shift under a changing climate.

### S.142.5 Unveiling the molecular mechanisms of drought stress response in cigar tobacco: insights from transcriptome and metabolome analysis

Huaxin Dai¹, Mengjiao Ding¹, Taibo Liang¹, Wang Zhong¹, Jinpeng Yang², Ruiwei Yang², Baoming Qiao², Chunlei Yang² and Yanling Zhang¹

1 Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China. 2 Tobacco Research Institute of Hubei Province, Wuhan, China

Cigar tobacco is sensitive to water stress and can serve as an ideal material for investigating the molecular mechanisms of drought resistance. In this study, we examined the response of Cigar tobacco to drought stress through physiological, transcriptomic and metabolic analyses. Cigar tobacco seedlings were subjected to 20 (DR) days of drought stress. Compared to control (CK), the results indicated that drought stress inhibited plant growth, physiological traits and enzyme activities. Transcriptome analysis showed that a total of 6446 differentially expressed genes (DEGs) in DR/CK were identified. These DEGs were found to be involved in tryptophan and α-linolenic acid metabolism, flavonoid and phenylpropanoid biosynthesis and the mitogen-activated protein kinase (MAPK) signaling pathway. Furthermore, most alkaloids and lipid content were reduced, amino acids and their derivatives, lignans, flavonoids and coumarins were increased under drought stress. This change can be attributed to the upregulation of type III polyketide synthase B (PKSB), flavonol synthase/flavanone 3-hydroxylase (FLS), and UDP-glycosyltransferases (UGTs), as well as the significant downregulation of R2R3MYB and lipid metabolism-related genes. The regulation of cutin, suberine and wax biosynthesis, the flavonoid pathway and α-linolenic acid metabolism contributes to Cigar tobacco's response to drought stress and provides valuable data for understanding the regulatory mechanisms underlying drought tolerance in Cigar tobacco.

## S.143 ETHNOBOTANY AND CONSERVATION OF MEDICINAL PLANTS. SESSION 4

### S.143.1 Ethnobotanical applications to treat snakebite in Colombia

Marcela Serna¹, Alejandro Serna², Omar Carmona³, Álvaro Cogollo¹, Diver Mayo¹, Yamileth Delgado¹, Jorge Ignacio Montoya¹, Mahmood Sasa⁴, Felipe Triana⁴, Fabian Bonilla⁴, Jeisson Gómez-Robles², Ana María Prieto¹, Jessica Paola Rey², Vitelbina Núñez²

1 Grupo INTEGRA, Facultad de Ingeniería, Tecnológico de Antioquia - Institución Universitaria, Medellín, Colombia. 2 Grupo Toxinología, alternativas terapéuticas y alimentarias, Universidad de Antioquia, Medellín, Colombia. 3 Líder comunitario vereda Caucheras, Mutatá, Colombia. 4 Instituto Clodomiro Picado, Universidad de Costa Rica, San José, Costa Rica

Colombia harbors a vast cultural and biological diversity, including a great richness of snakes. Most species are harmless to humans, although a few constitute a relevant public health problem as they induce severe envenomations and aftermath. This pathology primarily affects rural regions in poor conditions. In Colombia, over 5.000 cases of snake envenoming, with
<figure><img src="image_334.png" /></figure>

530 deaths, are reported yearly. Local communities use a vast number of botanic alternatives to treat snake-bite due to the precariousness of public health. We performed a literature review from the last 50 years about plants used against snakebite in Colombia, including information from interviews with local communities in Mutatá town at Northwest Antioquia. More than 300 plant species useful for snakebite were compiled after this review, while local communities from Mutatá use 131 medicinal plants, including 31 for snakebite. From these, 21 species had not been included in any ethnobotanical study or report, highlighting that traditional knowledge keeps providing valuable information in plant use and management. Laboratory tests were then carried out using ethanolic extracts of five species. We did not find antivenom bioactivity but found no differences between extracts from four plant species and ibuprofen, suggesting analgesic activity. In addition, the anti-inflammatory activity of these plants and the amount of polyphenols in their ethanol extract were tested. Information on the biological activity of plant extracts used by the communities is an important source to find bioactive molecules and promote adequate plant use to which the communities have access. Therefore, we encourage local communities to conserve these traditions as a parallel treatment to public health programs focused on distributing and using antivenoms. Ancestral knowledge must be respected and conserved while public health is guaranteed.

### S.143.2 Wealth of knowledge of medicinal plants used by three populations of the community of the urban area of the municipality of Neiva

Nestor A. Ramírez S.¹, Yipsyth M. Rodríguez M.¹, María C. Perdomo P.¹, Carlos A. Méndez P.¹

1 Departamento de Ciencias Naturales, programa de Biología Aplicada, Universidad Surcolombiana, Neiva, Colombia

The loss of ethnobotanical knowledge for medicinal purposes has increased in recent decades due to the appearance of technologies or other factors that reduce the importance of the acquisition and dissemination of this knowledge in new generations, causing acculturation processes in the young people of the current societies. Therefore, in this study, the richness of ethnobotanical knowledge present in three popula-

tions of different ages (young people ≤19 years, adults between 20 and 39 years and older adults ≥40 years) in the urban area of the city of Neiva, was determined. Through semi-structured interviews and the collection of data such as the species used, their parts used, the ways of preparation and consumption. Thus, older adults presented a greater wealth of knowledge (RQZ = 100%), reporting peppermint (Mentha spicata L.), calendula (Calendula officinalis L.) and aloe vera (Aloe vera Burm) as the most used to treat gastrointestinal conditions. neurological, musculoskeletal, or other types, using the leaves in greater proportion, due to their great capacity to store secondary metabolites responsible for the relieving effect of different symptoms and pathologies; This part was also used in the preparation of infusions, because it is the most intuitive way of preparing for oral administration. In conclusion, ethnobotanical knowledge is detrimental as populations become younger or very old, due to the growth of acculturation and memory loss due to old age, in addition, the use of plant resources is limited by the lack of vertical transmission of information, accentuated by the loss of biological wealth because of anthropogenic activities mostly related to local urbanization that fuels the degradation of ecosystems.

### S.143.3 Ethnobotanical inventory of plants belonging to the categories of use: aromatic and medicinal distributed in the metropolitan area

Sergio A. Salazar¹, Olga Y. Coronel¹, Carlos A. Méndez¹

Departamento de ciencias exactas y naturales, programa de Biología Aplicada, Universidad Surcolombiana, Neiva, Colombia

The flora species belonging to the categories of aromatic and medicinal use commercialized in the urban area of the city of Neiva were characterized, with 73 plant species, 61 genera and 38 families reported. The reported taxa were: Lamiaceae, Asteraceae and Myrtaceae families, these represented by more than 3 genera. It was evident that the most used plant resources are the leaves, inflorescences and stems as the most commonly used parts. Therapeutic actions mentioned to a greater extent were antispasmodic, antidiarrheal, antitussive, bronchodilator, diuretic, expectorant and hepatoprotective actions. In addition to, decoc-
tion and infusion technique of the fresh plant material were highlighted as the method of use most applied by the population. About 63% of the reported species are grown and obtained in the district of "Ulloa" province of "Rivera", 10% of the plant species are grown in district of "Cerro-Neiva" province of "Neiva" in the same department of Huila, and 27% of the plant species must be imported from the departments of Cundinamarca, Boyacá, Tolima and Cauca, showing that 70% of the interviewed people commercialize plants as their main socioeconomic activity, 24% commercialize plants due to lack of job opportunities, and 6% as an indirect economic resource.

## S.143.4 Quantitative Phytochemical Analyses of the Fruit and Propagation of Amomum dealbatum Roxb. (Zingiberaceae)

Maria Hazel C. Ubang¹, Hannah P. Lumista¹, Noel E. Lagunday¹, Florfe M. Acma¹

1 Plant Biology Division, Institute of Biological Sciences, Central Mindanao University, Musuan, Bukidnon, Philippines

Amomum dealbatum Roxb. is an indigenous wild ginger of the Philippines of which its fruits are eaten by the local people to treat stomach upsets. It's leaf sheaths were also reported to be utilized in making hats and other handicraft products. Despite its uses, no propagation efforts are done by the local people for this species. The study was conducted to determine the quantitative phytochemical components of the fruits and propagate A. dealbatum utilizing indigenous growing media. Phytochemical analyses revealed that the fruits of A. dealbatum possess antioxidant property which was determined using the phosphomolybdenum method, while total phenolic content was determined through the folin-ciocalteu method and flavonoids were determined using aluminum chloride colorimetric method. Analyses of the fruits revealed total antioxidant activity (TAA) of 32.66 -- 1.80 mg AAE/g dried sample, total phenolic content (TPC) has a value of 4.33 -- 2.45 mg GAE/g dried sample and total flavonoid content (TFC) of 6.38 -- 81.22 mg QE/g dried sample. In comparison to other studies, TAA and TFC are relatively higher, while TPC is relatively lower. Thus, the fruit extract of A. dealbatum contained flavonoid compounds which are higher in quantity compared with other plants which imply that the fruits of A.

dealbatum possess high antioxidant potentials which has many benefits for health. Trial propagation of the species using the seeds were also conducted. Boiling the seeds before sowing and covering the pots with plastic improved the chance of the seeds to germinate. T1 (garden soil + rice hull, 1:1) and T2 (garden soil + sawdust, 1:1) are the best growing media which resulted to higher germination and growth rate of young shoots, respectively. Hence, A. dealbatum has high TAA and TFC and that propagation utilizing the indigenous growing media is feasible.

## S.143.5 Ethnomedicinal appraisal of plants used for the treatment of gastrointestinal complaints by tribal communities of Western Himalaya

Rahmat Wali Muhammad Faraz Khan¹, Rahmatullah Qureshi¹, Zia-ur-Rehman Mashwani¹

1 Department of Botany, PMAS Arid Agriculture University Rawalpindi, Pakistan

Most of the mountain dwelling communities living in the Himalayas rely on traditional herbal medicines for primary healthcare needs. Present study was conducted in fairy meadows and allied valleys in District Diamir, Gilgit Baltistan autonomous territory in northern Pakistan. Documentation of traditional medicinal knowledge of local communities for the treatment of gastrointestinal disorders was carried out as a component of a wider medico-botanical expedition conducted in the entire base camp of the great Nanga Parbat peak during 2016-19. Various ethnobotanical parameters i.e., use value (UV), informant consensus factor (ICF), Fidelity level (FL), direct matrix ranking test (DMRT) and preference ranking (PR) were applied to evaluate the data collected during field surveys. The plants were also subjected to a comparative review for novelty assessment. A total of 61 medicinal plant species belonging to 55 genera and 35 families are reported here for the treatment of GIDs. Compositae was the leading family with 8 (13%) species. Fourteen gastrointestinal disorders were cured with 32% taxon reported for stomachic followed by diarrhea (15%) and constipation (14%). Highest use reports (5) and use citations (207) were reported for Mentha longifolia L. while highest UV (1.79) was obtained for Artemisia maritima L. Hylotelephium telephioides, A. maritima,
M. longifolia, M. piperita L., Allium cepa L., and A. annua L. exhibited 100% FL. Highest ICF was calculated against dysentery and flatulence. DMRT ranked Prunus persica L. first for its multipurpose uses. Taking constipation as a reference gastrointestinal disease, PR for ten plant species was calculated where H. telephioi-

des was ranked first followed by A. maritima. Present study concluded that 19 out of 61 plant species were documented for the first time with novel medicinal uses to cure GIDs. These plant species could act as potential reservoirs of novel lead compounds for the treatment of gastrointestinal disorders.

# S.144 POLYPLOIDY AND HOMOPLOID HYBRIDIZATION AS EVOLUTIONARY DRIVERS IN MEDITERRANEAN PLANTS. SESSION 2

## S.144.1 Polyploid hybridization in Kalanchoe: Understanding a new invasive complex in the Mediterranean basin

Joan Pere Pascual-Díaz¹,², Neus Besolí¹, Iván Pérez Lorenzo¹, Sophie Maiwald³, Tony Heitkam³,⁴, Ronen Shtein⁵, Jordi López-Pujol¹, Neus Nualart¹, Daniel Vitales¹, Sònia Garcia¹

1 Institut Botànic de Barcelona, CSIC-CMCNB, Barcelona, Spain. 2 Departament de Biologia Animal, de Biologia Vegetal i d'Ecologia - Universitat Autònoma de Barcelona, Bellaterra, Spain. 3 Faculty of Biology, Technische Universität Dresden, Dresden, Germany. 4 Universität Graz, Institute of Biology, Holteigasse 6, Graz, Austria. 5 The Steinhardt Museum of Natural History, Tel Aviv University, Tel Aviv-Yafo, Israel.

Invasive alien species pose a significant threat to global biodiversity, and ornamental plant trade is one of the primary causes of introducing alien plants. One such plant is *Kalanchoe ×houghtonii*, a purpoted artificial hybrid created from the crossing between *K. daigremontiana* and *K. tubiflora*. The two parental species are native to Madagascar, but together with the hybrid have become naturalised and a threat in several regions worldwide, particularly in Mediterranean climate areas. *Kalanchoe ×houghtonii* has four morphotypes, two of which are of known synthetic origin, and the other two which may occur naturally and could be derived from spontaneous gene flow between sympatric populations of the parentals. Reproduction is primarily promoted by propagules pro-

duced by the plant. From the cytogenetic point of view, *K. tubiflora* is tetraploid (2n=4x=68), while *K. daigremontiana* is diploid (2n=2x=34). For the hybrids, there are at least two cytotypes, a triploid (2n=3x=51) and a tetraploid (2n=4x=68). This study aims to elucidate the interplay between invasiveness, cytotype, and genetic diversity in *Kalanchoe ×houghtonii*. We sampled individuals from several wild locations of the Mediterranean basin, and we complemented the sampling with herbarium and cultivar samples from different regions of the globe. We performed whole genome sequencing and analysed the plastid and nuclear genomes – including the repetitive DNA content and the diversity of ribosomal DNAs – to infer the genomic composition of the hybrid complex. To better understand the contribution of each parental species in the different hybrid cytotypes, we enhanced the study with fluorescent in situ hybridisation (FISH) using 18S and 5S ribosomal DNA probes. Combining genomics, molecular data, and cytogenetics, we aim to provide a holistic understanding of the evolutionary history and the invasiveness of this new and aggressive hybrid complex in the Mediterranean habitats.

## S.144.2 The role of homoploid and polyploid hybridization in the evolutionary success of wild wheats

Stella Huynh¹

1 Institute of Research for Development, Montpellier, France
<figure><img src="image_335.png" /></figure>

Polyploidization, or whole-genome doubling, appears to be widespread across plants, particularly in angiosperms. However, it is known to induce sudden drastic changes in nascent polyploid species at both genomic and physiological levels. Allopolyploidy combines polyploidization and hybridization, which additionally causes epigenetic instabilities between genetically divergent maternal and paternal subgenomes that trigger bursts of transposable elements. Nevertheless, allopolyploid species are frequent and generally have a larger geographical distribution than their diploid progenitors. This suggests that successful species might have evolved evolutionary advantages pertaining to their allopolyploid state. To investigate the long-term impact of allopolyploidy on species evolution and adaptation, we used the wild wheat *Aegilops* L. species as model species, a well-known diploid-allopolyploid system in which half of the species are allopolyploids. We collected ~400 samples from four allopolyploid species and their four diploid progenitor species. Based on chloroplast data and amplicon sequencing of 30 low-copy nuclear genes, we inferred a dated phylogeny that confirmed the homoploid hybrid origin of the *Aegilops* genus as well as the multiple maternal and paternal origins of the polyploid species. In addition, by jointly analysing our genomic data with geographical and climatic data, we found that allopolyploids combine both their diploid progenitors' niches. This likely promoted faster recolonization of available suitable niches after the Last Glacial Maximum in allopolyploids as compared to their diploid progenitors. Moreover, this also confer higher adaptability potential to colonize new ecological niches.

### S.144.3 Ecological niches in the polyploid complex Linum suffruticosum s.l.

Ana Afonso¹, Sílvia Castro¹, João Loureiro¹, Juan Arroyo², Albano Figueiredo³, Sara Lopes¹, Mariana Castro¹

1 Centre for Functional Ecology, Associate Laboratory TERRA, Department of Life Sciences, University of Coimbra, Coimbra, Portugal. 2 Departamento de Biología Vegetal y Ecología, Universidad de Sevilla, Sevilla, Spain. 3 Centre of Studies in Geography and Spatial Planning, Department of Geography and Tourism, University of Coimbra, Portugal

The prevalence of polyploidy in the evolutionary history of angiosperms within the Mediterranean region appears intricately linked to the region's dynamic paleogeography and climatic oscillations. Polyploids often

possess distinctive traits, enabling them to circumvent exclusion by the minority cytotype. These traits may enable polyploid individuals to thrive in habitats divergent from their progenitors, thereby expanding into new places and promoting spatial segregation. This study delves into the role of environmental variables to explain current distribution patterns of the five main cytotypes of *Linum suffruticosum* s.l. (diploids, tetraploids, hexaploids, octoploids and decaploids) across its distribution range. Employing maximum entropy modelling alongside niche equivalency and similarity tests, we discerned the realised environmental niche of each cytotype. Discrepancies in environmental conditions among *L. suffruticosum* s.l. cytotypes were evident, with polyploids demonstrating an affinity for habitats characterised by elevated drought and soil pH levels, lower temperature ranges, and diminished soil water and cation exchange capacities. Diploids exhibited the broadest environmental niche, while polyploids occupied a subset of diploid niche. Although some polyploids exhibited ecologically equivalent niches, they did not coexist naturally. Furthermore, the ecological niche of this polyploid complex diverged between continents, with North African habitats featuring distinctions in soil texture, higher pH, lower cation exchange capacity, precipitation, and soil water capacity, as well as higher temperatures compared to habitats in southwest Europe. While these ecological conditions played a pivotal role in cytotype distribution, the mosaic pattern remained incompletely explained by environmental variables alone. Other factors, such as reproductive isolation and competitive interactions among cytotypes, likely contributed to the extant diversity and distribution patterns. This study yields pertinent insights into the niche requirements of each cytotype, laying the groundwork for subsequent competition and reciprocal transplant experiments.

### S.144.4 Intraspecific competitive performance of cytotypes is context-dependence over a latitudinal gradient

Mariana Castro¹, Maria C. Dias¹, João Loureiro¹, Brian C. Husband², Sílvia Castro¹

1 Centre for Functional Ecology, Associate Laboratory TERRA, Department of Life Sciences, University of Coimbra, Coimbra, Portugal. 2 Department of Integrative Biology, University of Guelph, Guelph, Canada
<figure><img src="image_336.png" /></figure>

Polyploidization, a common mutation observed throughout the evolutionary history of flowering plants, has played a pivotal role in shaping current plant diversity. While only a small fraction of neopolyploids (newly formed polyploids) successfully establish and spread, several factors contribute to this process. Crucially, neopolyploids must possess certain advantages over their diploid progenitors to gain a foothold, such as enhanced competitive ability. To investigate this competitive advantage, we compared the developmental and physiological responses of natural diploids, tetraploids, and synthetic neotetraploids of *Jasione maritima* var. *maritima* to intraspecific competition in controlled conditions. We also examined whether competitive abilities differed among populations within and beyond the contact zone. Diploids grown without competition exhibited superior developmental traits compared to the other cytotypes, such as increased size. Competition differentially impacted cytotypes, with neotetraploids demonstrating the least susceptibility and tetraploids the most significant negative effects. Notably, an asymmetric competitive response emerged across the latitudinal gradient. Populations outside the contact zone were most adversely affected, with tetraploid populations in the south experiencing the strongest negative impact compared to diploid populations in the north. The higher biomass and intermediate competitive capacity of diploids likely contribute to their persistence in northern distribution areas, while the dominance of neotetraploids under intraspecific competition would enable their establishment. Therefore, the asymmetric competitive abilities of cytotypes across their distribution range, potentially linked to environmental gradient adaptations, likely underlie the observed geographical patterns. Conversely, the similar competitive abilities of diploids and tetraploids within the contact zone may contribute to the maintenance of a dynamic and stable contact zone.

## S.144.5 Long-term climatic stability and hybridization as drivers of the endemic diversity of Picris in the Eastern Mediterranean

Juan Manuel Gorospe¹, Tomáš Fér¹, Jaromír Kučera², Ali Dönmez², Sırrı Yüzbaşıoğlu⁴, Zübeyde Uğurlu Aydın³, Roswitha Elisabeth Schmickl¹,⁵, Marek Slovák¹,²

1 Department of Botany, Charles University, Czech Republic. 2 Institute of Botany, Plant Sciences and Biodiversity Centre, Slovak Academy of Sciences, Slovakia. 3 Botany Section, Department of Biology, Faculty of Science, Hacettepe University Beytepe-Ankaraz, Turkey. 4 Department of Botany, Faculty of Science, Istanbul University, Vezneciler, Istanbul, Turkey. 5 Institute of Botany of the Czech Academy of Sciences, Průhonice, Czech Republic

The Mediterranean basin emerges as a biodiversity hotspot, housing an exceptionally high number of endemic entities. This biodiversity stems primarily from the region's long-term climatic stability, coupled with extreme geomorphological heterogeneity, including myriad island systems and high mountain ranges with diverse bedrock. Despite climatic stability, oscillations during the Pleistocene triggered contractions and expansions in the majority of organisms. These fluctuations led to recurrent contact between previously allopatric lineages or species, fostering both within and between species hybridization and introgression. The resultant extensive and recurring gene flow significantly contributed to the evolution of numerous hybridogenous lineages and speciation events. This study delves into the evolutionary history of the genus Picris L. (Compositae), serving as an exemplary model to investigate the impact of hybridization on the diversification and speciation processes. The genus Picris originated in the Mediterranean, featuring two major lineages—one evolving in Northern Africa and the other arising in the eastern Mediterranean, specifically in the southern region of Asia Minor and the Near East. Both regions host the highest diversity of the genus, with pronounced species diversity, particularly in the latter region. Previous studies suggested that, beyond allopatric speciation, hybridization and introgression likely play a significant role in this eastern Mediterranean lineage. Employing target enrichment with genome skimming (Hyb-Seq) and inferring both nuclear and plastome phylogenies, our investigation scrutinized the extent to which gene flow contributed to endemic diversity in the genus Picris in this region. Our findings indicate that secondary contacts and gene flow between species and their lineages occurred concurrently across several time horizons. The evolution of many endemics, particularly those from Asia Minor, was notably influenced by hybridization and introgression events.
<figure><img src="image_337.png" /></figure>

**S.144.6 Hybridization**
**processes and genetic**
**structure in Western**
**Mediterranean Tamarix**
**gallica populations**

Alejandro Terrones¹², Joaquín Moreno³,
Ana Juan²

1 Estación Experimental de Zonas Áridas, CSIC, Al-
mería, Spain 2 University of Alicante, Alicante, Spain.

3. Miguel Hernández University of Elche, Elche, Spain

The genus *Tamarix* comprises trees and shrubs that grow mainly in saline habitats. In the Western Mediterranean region, three different species naturally occur: *T. africana*, *T. boveana* and *T. gallica*. These three species do not form a monophyletic group and some morphological intermediate samples have been mentioned. The species *T. gallica* is the most common one, and due to its complex morphology, it has been misidentified with *T. canariensis*, an endemic species from the Canary Islands. The aim of this work is to study the phylogeographic history and genetic diversity of the *T. gallica* populations in the Western Mediterranean, and to understand the natural hybridization processes between *T. gallica* and different co-occurring species. For this purpose, fourteen polymorphic nuclear microsatellite markers were analyzed, and two different plastid regions were sequenced for 377 individuals of *T. gallica* from its complete natural distribution and some individuals from other related species. Our results show that current hybridization processes between co-existing species are much more common than previously reported, even between phylogenetically distant species. The three Western Mediterranean species *T. africana*, *T. boveana* and *T. gallica* hybridize between them with different degrees of introgression in natural populations that do not always involve morphological variability. Besides, *T. gallica* has a genetically complex relationship with other species, since it shares haplotypes with other geographically distant species from the Eastern Mediterranean region. Nonetheless, the genetic structure of *T. gallica* population reveals certain clear geographic patterns. In addition, African populations showed a higher genetic diversity, and it diminished towards the north of the Mediterranean Basin. Our results show that incomplete lineage sorting and reticulate evolution have been crucial in the evolution of the genus, and all these processes might be the underlying cause for the morphological confusion between species.
<figure><img src="image_338.png" /></figure>

Symposia Session 9

**S.145** GENOMICS OF LOCAL ADAPTATION.
SESSION 1

**S.145.1 Multiple domestications of Asian rice: evidence from domestication genes across the genome**

Chun-Yan Jing¹,², Fu-Min Zhang¹,², Xiu-Hua Wang¹, Mei-Xia Wang¹, Song Ge¹,²

1 State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China. 2 University of Chinese Academy of Sciences, Beijing, China.

Asian rice (Oryza sativa L.) is not only one of the world's most important crops but also serves as a model for studying crop evolution and understanding the progression of human civilization. However, the origin of Asian rice remains controversial for more than half a century. The controversy arises from four main factors: (i) the ambiguous population structure and genetic relationship of rice progenitors; (ii) poorly annotated samples that do not represent the gene pools of cultivated rice and especially wild rice; (iii) substantial gene flow and introgression among cultivar groups; and (iv) the lack of an effective approach to test for alternative hypotheses about domestication history. Of various speculations and opinions, two leading hypotheses stand out with empirical evidence: a single domestication event in China or multiple domestication events in geographically separate areas. These two hypotheses differ in their predicted history of genes/alleles selected during domestication. Here we amassed a dataset of 459 newly resequenced and 1119 publicly available genomes of wild and cultivated accessions that cover entire geographic range of wild rice and all known cultivar groups. With this large dataset, we developed a strategy to test for single vs. multiple domestication events; this strategy differs from previous studies by analyzing the selective sweep regions/selected genes that have single-origins across domesticated germplasm. We identified 993 selected genes that generated phylogenetic trees on which *japonica* and *indica* formed a monophyletic group,

suggesting that the domestication alleles of these genes originated only once in either *japonica* or *indica*. Importantly, the domestication alleles of most selected genes (~80%) stemmed from wild rice in China, but the domestication alleles of a substantial minority of selected genes (~20%) originated from wild rice in South and Southeast Asia, demonstrating separate domestication events of Asian rice.

**S.145.2** Genomic assessment of climate adaptation in an annual legume via artificial selection and assisted gene flow

Carlos Lara-Romero¹, Sandra Sacristán-Bajo¹, María L. Rubio Teso¹, Elena Torres², Alfredo García-Fernández¹, José M. Iriondo¹

1 Universidad Rey Juan Carlos, Móstoles, Madrid, Spain. 2 Universidad Politécnica de Madrid, Madrid, Spain.

In response to global warming, early flowering in temperate plants may provide adaptive advantages. This research delves into the utilization of artificial selection (AS) and assisted gene flow (AGF) to increase the adaptive potential of *Lupinus angustifolius* L. populations, particularly in flowering onset. Common garden experiments and genomic studies on diverse populations unveiled marked genomic distinctions between northern and southern counterparts. AS was effective in advancing flowering in northern populations but not in southern ones, suggesting prior natural selection for this trait. Importantly, the advancement of flowering brought about consequential alterations in various vegetative and reproductive traits. Several divergent SNPs between control and AS lines within each population were identified. This number was higher in northern populations compared to their southern counterparts. Southern populations, with limited genomic diversity and diminished responsiveness to selection, may have
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a reduced capacity for evolution and adaptation to climate change. However, their genotypes favor early flowering, proving advantageous in AGF initiatives in northern populations. To validate this hypothesis, AGF was performed by using pollen from southern individuals to pollinate northern plants. This resulted in a marked advance of flowering onset, accompanied by heavier seed production and reduced above-ground growth, highlighting the influence of AGF extending beyond the flowering phase, as observed for AS. Genomic analysis identified 36 highly divergent SNPs between the control and AGF lines, a validation reinforced by genotype-phenotype associations with flowering onset, seed weight, and above-ground growth. This dual validation robustly reinforces the impact of AGF on these traits on both genetic and phenotypic levels. Overall, our findings underscore the pivotal role of genomics in comprehending genetic modifications induced by AS and AGF, providing detailed information on underlying molecular changes that may be essential for climate change adaptation through early flowering.

genome SNP markers (Tournebize 2022). We provided a comprehensive map of selection signals in the genome of the *C. canephora* (Salojarvi 2023) both at the species level and within its major genetic groups. The genotype-environment association suggests regional adaptation to spatially varying environments of the recent past, with a special focus on the Eastern edge of the distribution, in Uganda (Kiwuka 2021). More specifically, we found signals of selection tightly linked to several genes involved in response to biotic and abiotic stress and in caffeine biosynthesis. We also observed variation of wild Uganda accessions in both growth and drought tolerance (Kiwuka 2023) that can be utilised for optimizing breeding programs initiatives to develop drought-tolerant varieties with adequate yield capacity. Our results support the hypothesis of present ecological gradient contributing to the structure of the genetic diversity with variation in adaptive traits. Moreover, assessing the adaptive capacities of the present populations will help to predict their response to future environmental changes.

### S.145.3 The adaptive potential of wild Coffee from Uganda in response to climate change

Poncet, Valérie¹, Aquino, Sinara¹,², Kiwuka, Catherine³, Tournebize, Rémi¹, Marraccini, Pierre⁴, Musoli, Pascal³, Anten, Niels⁵

1 IRD, UMR DIADE, Montpellier, France. 2 Federal University of Lavras, MG, Lavras, Brazil. 3 Naro, Kampala, Uganda. 4 CIRAD, UMR IPME, Montpellier, France. 5 Wageningen Univ. Wageningen, Netherlands

Understanding how organisms respond to their environment by altering physiological processes will increase our capacity to make predictions about adaptation to global climate change. Adaptive clines have been increasingly studied in plant species within temperate zones to understand adaptation of organism in natural populations. However, they are still poorly understood in tropical environments. *Coffea canephora*, cultivated as Robusta, is an interesting tropical tree model to investigate adaptation in the tropics, as it is largely distributed within the range of the lowland tropical rain forests of Africa. In particular, modifications occurring in genes related to abiotic stress tolerance make these genes candidate for enhanced resilience to future climate change. We combined the use of both captured regions sequenced for a set of candidate genes related to drought tolerance (de Aquino 2022) and whole

### S.145.4 Nucleotide and structural adaptive variation facilitate the colonization of stressful habitats in a wild tomato species

Gustavo A. Silva-Arias¹,², Kai Wei², Edeline Gagnon³,⁴,⁵, Remco Stam⁵, Aurelien Tellier²

1 Instituto de Ciencias Naturales, Facultad de Ciencias, Universidad Nacional de Colombia, Colombia. 2 Population Genetics, Department of Life Science Systems, School of Life Sciences, Technical University of Munich, Germany. 3 Department of Integrative Biology, College of Biological Science, University of Guelph, Canada. 4 Chair of Phytopathology, TUM School of Life Sciences, Technical University of Munich, Germany. 5 Department of Phytopathology and Crop Protection, Institute of Phytopathology, Faculty of Agricultural and Nutritional Sciences, Christian Albrechts University, Germany

Species distributed across broad environmental gradients are ideal models for unraveling the intricate signals of demographic and adaptive variation in genome dynamics. *Solanum chilense*, a wild tomato relative, thrives in narrow valleys along steep altitudinal gradients in the Andes and has recently colonized isolated areas in highland and coastal regions around the Atacama desert. Utilizing whole-genome sequencing, we correlated climatic changes with demographic shifts and the emergence of adaptive variations. Se-
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lective sweeps at 112 genes associated with flowering time and other abiotic response networks, indicate concerted adaptation during colonization to new regions. Complementary, integrating transcriptomic data in response to water deprivation revealed two distinct drought-response networks: cell cycle and fundamental metabolic processes. Interestingly, genes with older selective sweeps exhibit greater network connectivity, illustrating the importance of network rewiring to improve the species' ability to colonize new niches. To gain a more comprehensive understanding of gene network evolution in response to colonization of new habitats, we investigated gene copy number variation (CNVs), identifying 212,207 CNVs that reflect the species' demographic history and reveal candidate genes associated with stress response and, intriguingly, flowering time regulation. Environmental associations link CNV dynamics to climatic variables, pointing to natural selection's role in shaping genome structural variation. These findings provide insights into CNV-driven adaptation in marginal populations, enriching our comprehension of plant evolutionary responses to changing environments. Lastly, we comprehensively examine pathogen resistance genes (NLRs) in S. chilense. A refined genome and target-capture approach reveal larger within-population than between-population Presence-Absence Variation (PAV) of NLR loci. Contrary to abiotic-stress response networks, PAV in NLRs is linked to demographic history rather than environmental gradients, challenging prevailing notions about NLR diversity maintenance. This study enhances our understanding of evolutionary processes shaping genome diversity and structure in an outcrossing plant with high nucleotide diversity.

**S.145.5 Adaptive hybridization in Western European grapevine varieties**

Sara Freitas¹,²,³, João Nunes¹,²,³, João Tereso²,³,⁴,⁵, Miguel Carneiro¹,²,³, Herlander Azevedo¹,²,³

1. Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal. 2. CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Laboratório Associado, Campus de Vairão, Universidade do Porto, Vairão, Portugal. 3. BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, Vairão, Portugal. 4. MHNC-UP - Museum of Natural History and Science of the University of Porto - PO Herbarium,

University of Porto, Porto, Portugal. 5. Centre for Archaeology, UNIARQ, School of Arts and Humanities, University of Lisbon, Portugal.

Grapevine (Vitis vinifera L.) diversity richness results from a complex domestication history over multiple historical periods, which culminated in the creation of thousands of modern varieties with extensive phenotypic diversity. Unfortunately, the recent favoring of specific varieties/clones, climate change and the globalization-driven exposure to pathogens, has led to extensive genetic erosion in this widely cultivated and economically significant crop. Fighting this genetic erosion whilst addressing issues of resilience to climate change, yield and other traits, requires a crucial understanding of the genetic basis of grapevine variation. Such studies have been significantly enabled by the use of genomics approaches based on Next Generation Sequencing (NGS). Here, NGS-driven whole genome resequencing of individual genotypes has been used to tackle the extant genetic diversity present in grapevine germplasm, including a clarification of different features of its recent evolutionary path. Our results supported a model in which a central domestication event in grapevine was followed by post-domestication hybridization with local wild genotypes. This lead to the presence of an introgression signature in modern wine varieties across Western Europe, in which the Iberian Peninsula may have played a meaningful role. Furthermore, the examination of underlying genes suggests that environmental adaptation played a fundamental role in both the evolution of wild genotypes and the outcome of hybridization with cultivated varieties, supporting a case of adaptive introgression in grapevine. Acknowledgments: Fundação para a Ciência e Tecnologia (FCT/MCTES) for project GrapeVision (PTDC/BIA-FBT/2389/2020); FCT/MCTES and POCH/NORTE2020/FSE for support to S.F. (SFRH/BD/120020/2016); FCT/MCTES and POPH-QREN/FSE for support to M.C. (CEECINST/00014/2018/ CPI512/CT0002).

**S.145.6 The accumulation of deleterious mutations has a detrimental effect on tree growth in Pinus pinaster Aiton**

Rosalía Piñeiro¹, Lowana Cahn², Katharina B. Budde³, Agathe Hurel⁴, Adelaide Theraroz², Giovanni G. Vendramin⁵, Sara Pinosio⁵, Marina de Miguel⁶, Christophe
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Plomion², Myriam Heuertz², Santiago C. González-Martínez²

1 Evolutionary Biology Research Group, Interdisciplinary Centre of Chemistry and Biology, University of A Coruña, A Coruña, Spain. 2 INRAE, Univ. Bordeaux, BIOGECO, Cestas, France. 3 North West German Forest Research Institute, Department of Forest Genetic Resources, Hann Münden, Germany. 4 Department of Forest Growth, Silviculture and Genetics, Unit of Genome Research, Austrian Research Centre for Forests, Wien, Seckendorff-Gudent-Weg 8, Austria. 5 Institute of Biosciences and BioResources, National Research Council of Italy, Division of Firenze, Sesto Fiorentino, Italy. 6 EGFV, Univ. Bordeaux, Bordeaux Sciences Agro, INRAE, ISVV, Ville-nave d'Ornon, France

Genetic load, i.e., the accumulation of deleterious mutations in the genome, is predicted to cause a reduction in individual fitness. In plants, an increased number of deleterious mutations has been documented as a consequence of population bottlenecks, for instance in small or recently colonised populations at the margin of species ranges, or in

cultivated plants as a negative outcome of domestication. However, the actual adverse effect of genetic load on plant phenotypes remains virtually uncharacterised. We estimated genetic load in populations of the Atlantic-Mediterranean conifer maritime pine, Pinus pinaster Aiton, to examine its association with phenotypic traits related to growth and phenology (budburst) measured under common garden conditions. We observed a strong negative correlation between genetic load and tree height on the island of Corsica based on two different datasets (including 133,656 SNPs in 393 individuals and 10,185 SNPs in 334 individuals), thus suggesting a negative effect of the accumulation of deleterious alleles on tree growth on the regional scale. This association was further confirmed by a wide-range analysis including 464 individuals from 34 populations across the entire range of maritime pine in the western Mediterranean, Atlantic Europe and North Africa. Our study is one of the first to experimentally demonstrate adverse phenotypic effects of genetic load in a long-lived plant.

# S.146 NEW INSIGHTS INTO PHYLOGENOMICS, SYSTEMATICS AND EVOLUTION OF SALICACEAE

## S.146.1 Ecological gradients in various types of stress support different dimensions of plant chemical diversity: Salicaceae as a model

Martin Volf¹,², Jing Vir Leong¹,², Paola de Lima Ferreira¹,³, Ezgi Ogutcen¹, Natascha D. Wagner⁴, Gibson Aubona¹,², Simon T. Segar⁵, Juha-Pekka Salminen⁶, Vojtech Novotny¹,², Brian E. Sedio⁷,⁸

1 Biology Centre of the Czech Academy of Sciences, Branisovska 31, Ceske Budejovice, CZ. 2 Faculty of Science, University of South Bohemia, Branisovska 31, Ceske Budejovice, CZ. 3 Department of Biology, Aarhus University, Aarhus, DK. 4 Department of Systematics, Biodiversity and Evolution of Plants (with Herbarium), University of Goettingen, Goettingen, Germany. 5 Agriculture and Environment Department, Harper Adams University, Newport, UK. 6 Natural Chemistry Research Group, Department of

Chemistry, University of Turku, Turku, FI. 7 Department of Integrative Biology, University of Texas at Austin, Austin, TX, US. 8 Smithsonian Tropical Research Institute, Ancón, PA

Plants produce hundreds of thousands of specialized metabolites and many more probably remain to be discovered. There are currently multiple competing explanations for the origins and roles of chemical diversity in plants. We propose that to understand the origins and functions of chemical diversity, we need to decompose it into its various dimensions and link these to prevailing types of environmental stress. From this perspective, the willow family (Salicaceae) represents an ideal model system as the family is diverse from lowlands to highlands and from warm to cold climates. Our results from elevational gradients suggest that changes in the relative importance of stress by specialized insect herbivores and abiotic conditions drive differential phylogenetic trends in willow chemistry that, in turn, support increase in different dimensions of chemical diversity. Abiotic stress promotes directional phylogenetic increase in the concentration of metabolites such as flavonoids that protect plants from abiotic conditions. Abiotic pressures also act as a filter that selects for similar responses, which results
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in convergent chemical traits in plants growing under similar conditions. Contrastingly, divergent chemistry can improve plant fitness under strong pressure by specialized insect herbivores. Under prevailing pressure by specialized enemies, plants can thus be selected to switch to a completely different form of defence rather than invest in high concentration or richness of their current metabolites. The resulting divergence should allow for a 'chemical niche' partitioning and promote chemical variation among plant species. We suggest that similar gradients in the relative importance of various types of stress can underlay global trends in the diversity of metabolites. Specifically, we propose that the elevational clines may be analogous to latitudinal patterns of herbivory, host specialization, and quantitative investment in chemical defence, due to similar underlying gradients in the relative importance of abiotic stress and biotic interactions.

## S.146.2 Molecular evidence for sectional classification and spatio-temporal evolution of shrub willows (Salix L. subg. Chamaetia/Vetrix)

Pia Marinček¹, Étienne Léveillé-Bourret ², Stéphane M. Bailleul³, Martin Volf⁴, Li He⁵, Loïc Pittet¹, Elvira Hörandl¹, Tommi Nyman⁶, Sophie Karrenberg⁷, Campbell O. Webb⁸, Maria Tomoschevich⁹, Natascha D. Wagner¹

1 Department of Systematics, Biodiversity and Evolution of Plants (with Herbarium), University of Goettingen, Untere Karspüle 2, Göttingen, Germany. 2 Institut de recherche en biologie végétale (IRBV), Département de sciences biologiques, Université de Montréal, Montréal, QC, Canada. 3 Division Recherche et développement scientifique, Jardin botanique de Montréal, Montréal, QC, Canada. 4 Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic. 5 Eastern China Conservation Centre for Wild Endangered Plant Resources, Shanghai Chenshan Botanical Garden, Shanghai, China. 6 Department of Ecosystems in the Barents Region, NIBIO Svanhovd Research Station, Svanvik, Norway. 7 Department of Ecology and Genetics, Plant Ecology and Evolution, University of Uppsala, Uppsala, Sweden. 8 Museum of the North, University of Alaska, Fairbanks, AK, USA. 9 Central Siberian Botanical Garden of the Siberian Branch of the Russian Academy of Science, Herbarium, Novosibirsk, Russia

Genus *Salix* is the largest genus of family Salicaceae with about 450 species of woody plants predominantly inhabiting the Northern Hemisphere. A large portion of

the genus, about 300 species organized in 40 sections, is represented by the so called "shrub willows" belonging to subgenera *Chamaetia* and *Vetrix* that form a monophyletic clade. Several traditional molecular markers could not resolve the relationships within this clade. Traditional, morphology-based taxonomical classification continues to be under question due to vast inter- and intra-specific phenotypic variation and a lack of informative characters. The processes of hybridization, introgression and polyploidization played an important role in the evolution of willows and further complicated research of this genus. Thus, shrub willows remain a hard challenge that fascinates biologists to this day. In our project, we selected a RAD sequencing approach to generate a huge number of SNPs to disentangle the interrelations of shrub willows. This way we wanted to find evidence to justify or refute the current sectional classification. We were able to sequence more than 400 individuals of over 120 species of shrub willows collected worldwide. Using a maximum likelihood estimation, we built a well resolved phylogeny. Our data revealed that most of the species form monophyletic clades, though some exceptions show polyphyly. Morphological traits have evolved multiple times in shrub willows and current sectional classification does not reflect true biological relationships. Polyploidy evolved numerous times as a result of allo- and auto-polyploidization events. Patterns of species radiation could be observed in regions such as North America and Chinese Hengduan mountains. Migration and long distance dispersal further shaped the diversity of shrub willows. Our research presents a strong backbone for future studies on shrub willows regarding taxonomy, hybridization, polyploidization, ecology and many more.

## S.146.3 A multi-method genomic approach to phylogenetic reconstruction of the Salicaceae

Ezgi Ogutcen¹,², Paola de Lima Ferreira¹,³, Natascha D. Wagner⁴, Jing Vir Leong¹,⁵, Gibson Aubona¹,⁵, Jeannine Cavender-Bares⁶, Jan Michálek¹,⁷, Lucy Schroeder⁶, Brian E. Sedio⁸,⁹, Radim Vašut¹⁰,¹¹, Martin Volf¹,⁵

1 Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, CZ. 2 Department of Environment and Biodiversity, Paris Lodron University of Salzburg, Salzburg, AT. 3 Department of Biology, Aarhus University, Aarhus, DK. 4 Department of Systematics, Biodiversity and Evolution of Plants, University of
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Goettingen, Göttingen, DE. 5 Faculty of Science, University of South Bohemia, Ceske Budejovice, CZ. 6 Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN, USA. 7 Institute of Microbiology of the Czech Academy of Sciences, Centre Algatech, Trebon, CZ. 8 Department of Integrative Biology, University of Texas at Austin, Austin, TX, US. 9 Smithsonian Tropical Research Institute, Apartado 0843-03092, Ancón, PA. 10 Department of Botany, Faculty of Science, Palacký University in Olomouc, Olomouc, CZ. 11 Department of Biology, Faculty of Education, Palacký University in Olomouc, Olomouc, CZ

With over 1,400 species, the Salicaceae exhibit broad distribution across tropical and temperate forests. Despite ongoing efforts in genome-based approaches, the family lacks a comprehensive phylogeny due to high rates of hybridization and polyploidy. With a sampling of 75 species, our study aimed to reconstruct an extensive Salicaceae phylogeny using whole-genome sequence (WGS) data. We utilized a set of 23,393 RAD-Seq loci from *Salix* as an initial reference library for mapping. The resulting matrix was then used in a second round of mapping, thereby extending the reads recovered from the main WGS dataset. Additionally, we extracted two targeted-capture subsets from our WGS data: the Angiosperms353 and a Salicaceae-specific gene sets. Applying various quality-trimming parameters, we compared phylogenetic informativeness across datasets. We performed ML-based phylogenetic reconstructions using supermatrix and coalescent-based supertree approaches. The length and the number of loci recovered from the WGS data varied between different filtering schemes. Compared to the WGS datasets, both targeted-capture datasets have longer loci with more parsimony informative sites. For both targeted-capture datasets, locus recovery rates were higher for the ingroup samples than the outgroups. Overall, phylogenetic reconstructions revealed consistent family-level topologies, highlighting the monophyly of the family and detailed relationships within. In contrast, the relationships within *Salix* showed lower support and some incongruence across different methods and datasets. In most phylogenies, the subgenera *Chamaetia* and *Vetrix* were recovered as monophyletic, but monophyly of the subgenus *Salix* was not supported in any of the phylogenies. Our study provides a thorough comparison of various genome-based sequencing datasets and phylogenetic reconstruction methods, while enhancing our understanding of the Salicaceae evolution by providing valuable insights into the complex relationships within the family.

## S.146.4 Challenges for dating divergence times in the Salicaceae: hybridization and fossil calibration

Brian J. Sanderson¹,⁸,¹⁰, Diksha Ghambir¹, Guanqiao Feng¹, Nan Hu¹, Quentin C. Cronk², Diana M. Percy², Francisco Molina Freaner³, Matthew G. Johnson¹, Lawrence B. Smart⁴, Ken Keefover-Ring⁵, Tongming Yin⁶, Tao Ma⁷, Stephen P. DiFazio⁸, Jianquan Liu⁷,⁹

¹Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA. ²Department of Botany, University of British Columbia, Vancouver, BC, Canada. ³Universidad Nacional Automa de Mexico, Hermosilla, Mexico. ⁴Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech, Geneva, New York, USA. ⁵Departments of Botany and Geography, University of Wisconsin-Madison, Madison, WI, USA. ⁶Key Laboratory of Tree Genetics and Biotechnology of Jiangsu Province and Education Department of China, Nanjing Forestry University, Nanjing, China. ⁷Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & College of Life Sciences, Sichuan University, Chengdu, China. ⁸Department of Biology, West Virginia University, Morgantown, WV, SA. ⁹State Key Laboratory of Grassland Agro-Ecosystem, Institute of Innovation Ecology & College of Life Sciences, Lanzhou University, Lanzhou, China. ¹⁰Current Address: Department of Molecular Biosciences, University of Kansas, Lawrence, KS, USA

Understanding divergence times in the Salicaceae (poplars, willows, and relatives) are crucial for understanding environmental impacts on trait evolution such as sex chromosomes, pollination type, stature, and cold hardiness. Two factors underlie the challenges to estimation of divergence times: 1) the impact of hybridization on estimation of the species tree and 2) accurate placement of fossils onto the tree for calibrating the molecular clock. We used sequence capture protocols to investigate the intricate gene histories in both *Populus* and *Salix*. These histories often conflict with the overall species tree of the Salicaceae family. The diverse gene histories are linked to evidence of gene flow resulting from hybridization, dating back to the earliest divergence events in these genera. Current coalescent dating methods demand extensive computational resources and are feasible only when a limited number of genes
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are used. We show that variations in gene tree histories can significantly affect estimates of divergence times. Furthermore, despite the abundance of Salicaceae fossils, their limited morphological characteristics make it challenging to confidently place them within the family tree. Our findings demonstrate that calibrating the molecular clock using the most reliable fossils of the origins of subgenera within Salix and Populus leads to a substantial alteration in estimated divergence times compared to calibrating the clock based on the most reliable assessment of the Populus+Salix clade's origin time.

## S.146.5 Evolution of sexual systems in poplars and its relatives

Niels A. Müller¹, Birgit Kersten¹, Matthias Fladung¹

1. Thünen Institute of Forest Genetics, Grosshansdorf, Germany

Although hundreds of plant lineages have independently evolved dioecy, i.e., separation of the sexes, the underlying genetic basis has been resolved only in a small subset of species. Additionally, transitions between sexual systems, such as monoecy and dioecy, remain largely elusive. Here we show that diverse poplar species carry partial duplicates of an *ARABIDOPSIS RESPONSE REGULATOR* 17 (*ARR17*)-like gene in the male-specific region of the Y chromosome. These duplicates give rise to small RNAs apparently causing male-specific DNA methylation and silencing of the *ARR17* gene. Excitingly, CRISPR/Cas9-induced mutations demonstrate that *ARR17* functions as a single-gene sex switch triggering female development when 'on' and male development when 'off'. Despite repeated turnovers, including transitions between XY and ZW systems, sex-specific regulation of *ARR17* is conserved across the *Populus* genus. Interestingly, *ARR17* appears to be involved in sex determination in the sister genus *Salix* as well. To address the question of when *ARR17* evolved its sex-determining function in the Salicaceae family and whether the same gene may control monoecy and dioecy, we analyzed *Poliothyrsis sinensis*, the closest monoecious relative of poplars and willows. We present first functional genomics results of *Poliothyrsis* and discuss their implications for the evolution of sexual systems in the Salicaceae.

In summary, our work illustrates how single-gene sex determination in combination with minimal sexual conflict can facilitate repeated turnovers and prevent expanding recombination suppression and sex chromosome degeneration.

## S.146.6 Sex chromosome evolution in Salix

Xiaomeng Mao¹, Pär Ingvarsson², Vinciane Mosson¹, Sophie Karrenberg¹

1. Department of Ecology and Genetics, Uppsala University. 2. Department of Plant Biology, Swedish University of Agricultural Sciences

Sex chromosomes have been hypothesized to be drivers of speciation, however, they are difficult to study due to their complex and dynamic evolutionary trajectories. The species-rich, dioecious genus *Salix* (willows) has homomorphic sex chromosomes and is an ideal model system for the evolution of sex chromosomes. We de-novo assembled a chromosome-level genome of the dwarf willow *S. herbacea* using Pacbio HiFi and HiC sequencing. We detected a female heterogametic sex determination system and resolved both Z and W haplotypes on chromosome 15. Two sex-associated regions were located at both ends of a ~5Mb inversion: a 1.8Mb female-specific region (missing from males) and a 0.5Mb region with high sequence divergence between sexes. This suggests stepwise evolution of the sex chromosomes. The sex-associated regions of *S. herbaeca* show only partial synteny with the closely related *S. purpurea* indicating that the region expanded and evolved recently. We currently explore the evolutionary mechanisms that gave rise to the sex-associated regions in *S. herbaeca* using whole genome re-sequencing of two *S. herbacea* populations and populations of eight further *Salix* species from the *Vetrix* section. We analyze signatures of selection as well as differentiation between populations and species in ZW homologous regions. With this study, we contribute to the understanding of fast-evolving sex chromosomes with possible consequences for lineage divergence and speciation.
# S.147 SPEEDING UP CONSERVATION IN POORLY KNOWN ORGANISM GROUPS – NEW APPROACHES TO BRYOPHYTE CONSERVATION.
## SESSION 1

### S.147.1 Bryophytes and lichens become increasingly visible through remote sensing data: new avenues for research and conservation

Carlos Cerrejón¹,², Enrique Hernández-Rodríguez², Maxence Martin², Nicole J. Fenton², Osvaldo Valeria²,³

1 Conservation research group. Biodiversity and Global Change, Universidad de Extremadura, Badajoz, Spain. 2 Institut de recherche sur les forêts, Université du Québec en Abitibi-Témiscamingue, Rouyn-Noranda, Québec, Canada. 3 Hémera Centro de Observación de la Tierra, Escuela de Ingeniería Forestal, Facultad de Ciencias, Universidad Mayor, Huechuraba, Santiago, Chile

Bryophytes and lichens are ubiquitous taxa contributing significatively to total biodiversity and ecosystem functioning worldwide. Conservation of these ecologically important and sensitive species is however hampered by current knowledge gaps on their diversity, ecology and distribution. Remote sensing (RS) can significantly aid to fill these gaps through its direct and indirect approaches. The direct approach consists in detecting the target species or specific attributes by directly capturing their spectral information, while the indirect approach focusses on the characterization of any habitat factor related to any aspect of the species, allowing for the quantification and eventual specialisation of their relationship across the landscape. Here, we provide a systematic review on the application of RS for the study of bryophyte and lichens, whose potential, as an emerging research area, remains largely unexplored. We identified a total of 101 articles on this topic, of which 55 and 46 followed a direct and indirect approach, with bryophytes and lichens being relatively well represented across them. Both approaches have used very diverse RS information, from purely spectral to

indicative of topography, geology, vegetation, wetness, presence of snow, land uses or natural disturbances. They have been derived from a wide variety of airborne and satellite sensors (either optical or active). The direct approach has mainly focused on cover, health and vegetation types, while the indirect approach on α- and β-diversity, distribution, cover and abundance. By synthetizing the results and performances obtained in the reviewed articles across RS approaches, sensors, spatial resolutions and target aspects, we provide discussion on the limitations, knowledge gaps and new opportunities on the use of this technology for bryophyte and lichen research, as well as on the promising role that RS can play for improving their representation in conservation planning.

### S.147.2 Cryopreservation of gametophytes as a tool for ex-situ conservation

Jennifer K. Rowntree¹, Neil Bell², Jonathan Kendon³, Izadora Kervin¹, Dave Lamacraft⁴, Silvia Pressel⁵

1 University of Plymouth, Plymouth, UK. 2 Royal Botanic Garden Edinburgh, Edinburgh UK. 3 Royal Botanic Gardens, Kew, Richmond, UK. 4 Plantlife International, Salisbury, UK. 5 Natural History Museum, London, UK

Between 2000-2016 a collection of UK threatened bryophytes was established at the Royal Botanic Gardens, Kew as part of the UK's conservation commitments. The majority of accessions were initiated from leafy gametophore material with dried and encapsulated protonemal material subsequently cryopreserved for long-term storage. Regeneration success rates after removing material from short-term cryo-storage were high, with all species able to regrow and 100% regeneration success for 50% of the species tested. However, viability after long-term storage remained unknown. In 2020 and 2021, after at least 14 years in the deep freeze, two species of
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ongoing conservation interest (*Ditrichum cornubi-cum* and *Orthodontium gracile*) were removed from the collection. Both successfully regenerated and were re-established into tissue culture, where they have been growing in protonemal form and pro-ducing leafy gametophores. Experiments are un-derway at the University of Plymouth to test weaning methodologies to enable growth in more natural environments. The impacts of long-term cryopres-ervation and the feasibility of using such material for reintroductions will be presented and discussed. The Kew collection contains over 20 species and the successful regeneration of two mosses is a hope-ful sign that cryopreservation could be a useful tool for long term storage of bryophytes. This work forms part of a programme to develop standard methods for the reintroduction of bryophytes from cryopreserved collections and the removal and regenera-tion of additional species is planned.

### S.147.3 Bryophytes as the canaries in the coal mine – using eDNA from 35 years of air samples to analyse changes in bryophyte phenology

Fia Bengtsson¹,², Nils Cronberg¹, Johan Ekroos¹,³,⁴, Jose A. L. Villegas⁵, Abu B. Siddique⁵, Per Stenberg⁵

1 Biodiversity unit, Lund University. 2 Norwegian Institute for Nature Research. 3 Department of Agricultural Sciences, Plant Production Sciences, University of Helsinki, Helsinki, Finland. 4 Helsinki Institute of Sustainability Science, University of Helsinki, Helsinki, Finland. 5 Department of Ecology and Environmental Sciences, Umeå University

Bryophytes are physiologically highly dependent on climatic conditions, making them useful as early indicators of ongoing changes in biological communities. However, monitoring bryophytes is highly work-intensive, rarely carried out over extensive periods and even less frequent at temporal scales that allow detection of changes in phenology. eDNA approaches are surging in biodiversity monitoring, but bryophyte applications are still in their infancy. We explore a unique eDNA dataset (from the project Swe-BITS) based on airborne particles originally collected from Kiruna, northern Sweden, by FOI (Swedish Defence Research Agency) to detect radioactive

downfall. Biological material, that had accumulated on glass fibre filters exchanged weekly during 35 years, was analysed for total DNA and matched against genetic data. As much as ten percent of the generated reads originated from wind-dispersed bryophyte spores. We selected 16 taxonomic groups based on information about local presence, available genomic data for discrimination and level of phylogenetic isolation. We found substantial changes in onset of spore dispersal in spring throughout the time series, with most bryophyte taxa advancing their spore dispersal a whole month, extending the entire season a month or more. The end-of-season timing remained largely the same. Phenological shifts may predate population changes, and both occurrence and phenology data from eDNA may inform conservation planning and efforts. At present, the taxonomic precision of the method is limited by the genomic resources available, but the possibilities are steadily increasing. The proportional nature of the data, with varying relative abundances of different kinds of airborne biological matter between sampling events, makes the analyses computationally challenging. We conclude that eDNA from air samples is a promising and potentially cost-efficient way to monitor changes in bryophyte communities.

### S.147.4 Extinction risk of European bryophytes predicted by bioclimate and traits

Kristel van Zuijlen¹,², Irene Bisang¹,², Michael P. Nobis¹, Ariel Bergamini¹

1 Swiss Federal Research Institute WSL, Birmensdorf, Switzerland. 2 Swedish Museum of Natural History, Stockholm, Sweden

Extinction risk is not randomly distributed among species but depends on species traits, their relationship to environmental factors such as climate and land use, and corresponding threats by global change. While knowledge of which factors influence extinction risk is increasingly available for some taxonomic groups, this is still largely lacking for mosses, liverworts and hornworts. Here, we used random forest models to study which biological and ecological traits and bioclimatic variables are important predictors for extinction risk in European bryophytes. We found that bioclimatic variables were the most important predictors for extinction risk, most notably precipitation and precipitation seasonality. Import-
ant biological traits were plant size, life strategy and reproductive traits while important ecological traits were continentality and elevational range of species distributions. In general, species living at climatic extremes and/or those with a narrow environmental range are more likely to be threatened with extinction. In addition, small-sized species and/or species with low sexual or asexual reproductive effort and/ or larger spore size are more likely to be threatened. Our findings indicate that future climate change will be an important driver of bryophytes' extinction risk, while biological and ecological traits will likely become most relevant for species in coping with future threats.

### S.147.5 Project «Searching for the 'Brillófito'»: enhancing knowledge of the intriguing and rare luminous moss Schistostega pennata in th

Jairo Robla¹, Víctor González-García², Sara Santamarina³, Pablo Aguado-Ramsay⁴, Mikel Artazkoz⁵

1. Estación Biológica de Doñana (CSIC), Sevilla, Spain. 2 Instituto Mixto de Investigación en Bio-diversidad (Univ. Oviedo - CSIC - Princ. Asturias), Mieres, Spain. 3 Universidad de León, León, Spain. 4 Universidad Autónoma de Madrid, Madrid, Spain. 5. Universidad Pública de Navarra, Pamplona, Spain

The luminous moss, Schistostega pennata (Hedw.) F.Weber & D.Mohr, is a Holarctic moss known for its unique green-emerald glowing protonema when exposed to sunlight. This distinctive feature has inspired several stories surrounding this intriguing feature. The distribution in the Iberian Peninsula represents the westernmost extent in Europe, with only 73 confirmed locations to date. It thrives primarily in challenging environments such as caves, mines, and crevices, making the discovery of new populations a complex task. Despite its uniqueness, S. pennata faces conservation concerns and is categorised as Vulnerable or near Threatened in several Iberian Red Lists. Yet, the criteria for such designations remain unclear. To enhance understanding and contribute to the conservation efforts of this species, the «Searching for the 'Brillófito'» project was initiated. This project leverages citizen science to gather data on the distribution, ecology, and conservation status of the luminous moss. A comprehensive scientific communication campaign through newspapers,

social media, and lectures was also launched to raise awareness and engage the public in moss-related initiatives. The response exceeded expectations, with citizens locating more than 15 new populations across the Iberian Peninsula. Some of these populations revealed new habitats not previously described for the Iberian populations. Interestingly, some were discovered in areas not predicted as optimal by the first species distribution model for the species, highlighting the complexity of understanding the ecological requirements of the species. Many questions remain regarding its ecology and biology in the Iberian Peninsula. These include the scarcity of populations, the mechanisms of dispersal and connectivity between them, the relationship with other non-Iberian populations, and whether luminescence could have an associated function not previously described. Unravelling these mysteries will require further research and an understanding of the role of the moss in its unique ecosystems.

### S.147.6 Neglected plants: towards a comprehensive extinction risk assessment of the Brazilian bryophytes

Eduardo T. Amorim¹, Paulo E.A.S. Câmara², Denilson Fernandes Peralta³, Juçara Bordin⁴, Andre Eppinghaus¹, Camila Nardy¹, Carlos Ferreira¹, Daniel Maurenza¹, Fernanda Fraga¹, Fernanda Wimmer¹, Gláucia Crispim¹, Gustavo Martinelli¹, Lucas Arguello¹, Lucas Jordão¹, Mário Gomes¹, Monira Bicalho¹, Pablo Melo¹, Vicente Calfo¹, Eduardo Fernandez¹

1 Centro Nacional de Conservação da Flora/Jardim Botânico do Rio de Janeiro, RJ, Brazil. 2 Departamento de Botânica, Universidade de Brasília, Brasília, Brazil. 3 Núcleo de Briologia, Instituto de Pesquisas Ambientais, São Paulo, SP, Brazil. 4 Universidade Estadual do Rio Grande do Sul, Osório, RS, Brazil

Over the last 50 years, escalating biodiversity losses, coupled with persistent and intensifying pressures, have resulted in the extinction of species before their scientific description. The Brazil stands out as a country with a vast diversity of bryophytes, with consistent progress done in past years towards a complete assessment of its flora. However, major gaps still exist, making the conservation of
<figure><img src="image_346.png" /></figure>

this group challenging. In this scenario, automat-
ed tools that assist in species extinction risk detec-
tion emerges as crucial alternatives to accelerate
the process of biodiversity protection. Thus, we
highlight the initiative of the Brazilian conservation
community to optimize and automate processes
for calculating criteria and parameters needed to
assess species' extinction risk. Aiming to expedite
the risk assessment and direct efforts towards truly
threatened species, a list of endemics was created,
with names accepted and validated by the back-
bone taxonomic of the Flora of Brazil 2020, and of
broad occurrence, using the rapidLC method, to-
talling 100 species. The acquisition of occurrence
records relied on databases such as Splink, JABOT,
and GBIF. For a complete assessment, various bi-
ological data were extracted from available on-

line databases, covering biomes, habitats, incident
threats, among others. A web application devel-
opment system was elaborated through the Shiny
package of the R software, enabling the delivery of
datasets to experts who validated determinations,
confirming species distributions, and compiling bi-
ological data. The bryophytes were then assessed
following the IUCN criteria, resulting in 48 species
immediately assessed as Least Concern, while the
remaining 52 were forwarded for continuous as-
sessment, evaluated by the National Centre for
Flora Conservation, Brazil's National and Global Red
List Authority. The use of these tools represents cru-
cial steps in the creation of a consistent red list for
Brazilian bryophytes, emphasizing the importance
of expediting risk assessments, especially in mega-
diverse tropical regions like Brazil.

**S.148** SYSTEMATICS, FLORISTICS, AND
CONSERVATION: FACILITATING DATA
INTEGRATION TO PROMOTE SOUND SCIENCE.
SESSION 2

S.148.1 Bringing plants to
the table: Assessing bias to
build a subsample of plants
that represents global
diversity patterns

Baldaszti, L.¹², Pironon, S.³,⁴, Brummitt, N.A.⁵,
Lehmann, C.¹², Moonlight, P. M.²,⁶, Särkinen, T.²

1 University of Edinburgh, UK. 2 Royal Botanic Garden Edinburgh, UK. 3 Royal Botanic Gardens, Kew, UK. 4 UNEP-World Conservation Monitoring Centre, UK. 5 Natural History Museum, UK 6 Trinity College Dublin, Ireland

More than 40% of the world's plant species are rare
and threatened by extinction. While destruction
of the natural world has accelerated dramatical-
ly over the past decades, our knowledge of global
plant biodiversity patterns has not accelerated at
similar rates, with only 20% of the species having
their extinction risk formally assessed by now. As our
knowledge of plant biodiversity is incomplete, all
global studies of plant diversity patterns are based
upon subset of species. The included species and

the amount of data available for those species are
the result of >300 years of biased plant collecting.
So, while studying diversity patterns based upon all
available distribution data has its merits, it can also
lead to a severely distorted view of global biodi-
versity patterns. It is thus necessary to identify and
reduce these biases or find alternatives to better
estimate extinction risk and biodiversity patterns
from incomplete data. Determining the number of
species needed to accurately represent different
aspects of plant biodiversity patterns at a global
scale thus has important implications for the validity
of previous studies but can also be incorporated in
future studies. We aim to identify the number of spe-
cies needed to represent different aspects of global
vascular plant biodiversity patterns including spe-
cies, phylogenetic, floristic, and functional diversity
using the World Checklist of Vascular Plants (WCVP)
as a baseline. We use this information to deter-
mine how well datasets such as the IUCN Red List of
Threatened Species, the Species Red List Index, and
openly available plant occurrence data incorporate
different aspects of plant biodiversity. The outputs
will be of interest for biodiversity conservationists
and macroecologists.
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## S.148.2 The evolutionary building up of a biodiversity hotspot: new insights of Andalusian Flora diversity from phylofloristic perspective

Carmen Benítez Benítez¹, Alejandra de Castro¹, José Luis Silva¹, Juan Viruel², Marcial Escudero¹, José Carlos del Valle¹, Montserrat Arista¹, Juan Arroyo¹

1 Department of Plant Biology and Ecology, Universidad de Sevilla, Seville, Spain. 2 Ecosystem Stewardship Department, Royal Botanic Gardens, Kew, UK.

Southern Spain, recognized as a plant biodiversity hotspot, boasts remarkable species diversity, notable endemism, and relictness, by its high environmental variability and dynamic geomorphological history. These factors have acted as drivers of migration and diversification in this region, contributing to the richness of its plant landscape. The three National Parks in Andalusia (Doñana, Sierra Nevada, Sierra de las Nieves) are considered the jewels of the crown, thought to exemplify the majority of ecological and evolutionary processes underlying the region's diversity. The flora of these natural reserves comprises a notably high percentage of species of the entire Andalusian flora. This, in turn, offers an assurance for preserving not only individual species but also populations and communities. The fields of phylofloristics and spatial phylogenetics open new avenues for understanding how evolutionary processes shape phylogenetic relationships of species in a region, elucidating their evolutionary patterns, which is particularly insightful when applied to biodiversity hotspots. Therefore, leveraging this new perspective, we used a megaphylogenomic approach (HybSeq, based on angiosperm353) to study the woody flora in these parks. Particularly, we explored the historical effects on biodiversity in these megadiverse areas and compare the patterns within and among territories. The phylogenomic results enabled us to calculate the phylogenetic diversity and signal associated with life-history traits (pollination, dispersal, flowering), ecological factors (habitat, substrate, altitude), and distribution within representative species ensembles of these biodiversity enclaves. Indeed, life-history traits displayed a strong phylogenetic signal and a pronounced overdispersal

pattern. Interestingly, many ecological specialized character states, as a proxy of niche space, exhibited notable phylogenetic clustering, indicating their dominance within closely related species. These findings will provide new insights into the integration of evolutionary history into the criteria of management of protected areas and lineages.

## S.148.3 Techniques for managing biodiversity information overload: some examples with bryophytes

John C. Brinda¹

1 Missouri Botanical Garden, St. Louis, USA

Our collective ability to effectively curate, summarize, and visualize biodiversity data has broader implications beyond botany into the disciplines of conservation science and policy. It is vitally important that decisions made in those areas are based on the best available science, and that starts with the data we create and manage. However, the increasing pace of digitization of biodiversity data threatens to overwhelm our capacity to capture, curate, and use these data. Direct access to the raw data upon which traditional floras, checklists, monographs, etc. are built, would seem to be a boon to both scientific research and policy development. However, in actual practice the results are mixed. End users often struggle to use these data effectively because they are provided 'as is', flaws and all. Moreover, significant effort is wasted as these data are downloaded separately by multiple parties and 'cleaned' for different use cases. In most cases, improvements made to these data externally never find their way back upstream to the original source and in turn, to other end users. Such duplication of effort generally results in reduced productivity without any significant increase in data quality. Moreover, the problem of curating these digital and online representations of botanical data has often fallen to botanists who are already overloaded and has been exacerbated by the lack of available tools for doing this efficiently. Here we illustrate some common problems and use cases using a dataset developed for bryophytes. While many of these problems are not new, practical solutions either remain elusive or are at best poorly implemented. Our aim is to provoke thoughtful discussion about potential strategies for overcoming these challenges.
<figure><img src="image_348.png" /></figure>

**S.148.4 From the extended specimen to conservation assessment: predicting species Red List status from publicly available information**

Alexander Zizka¹², Daniele Silvestro³

1 Department of Biology, Philipps-University Marburg, Marburg, Germany. 2 Naturalis Biodiversity Center, Leiden, The Netherlands. 3 Department of Biology, University of Fribourg

The IUCN Red List of threatened species (RL) is the most authoritative global quantification of extinction risk, and widely used in ecological research and applied conservation. Yet, due to the time-consuming assessment process, the RL is taxonomically and geographically biased, in particular towards the global North and charismatic taxa. One promising approach to speed up RL assessments and overcome these biases is the use of AI to predict extinction risk based on the combination of information from digitized collection specimens and citizen science data with remote sensing information on the environment. Here, we present IUCNN, an approach using deep learning models to predict species RL status from publicly available geographic occurrence records (and other data, such as traits if available). We show that AI methods can reach accuracies up to 95% in identifying threatened species and use the results from three recently published case studies -on the orchid family, global tree species and the biota of Madagascar- to illustrate the potential and caveats on using AI and collection specimen to predict species extinction risk.

**S.148.5 Identifying gaps in the ex situ conservation of native plant diversity in China**

Jianfei Ye¹

1 School of Ecology, Sun Yat-sen University, Shenzhen, China

Due to intensified human pressure and climate change, *ex situ* conservation measures have become essential for conserving Earth's remaining biodiversity, but the development of targeted *ex situ* conservation strategies based on con-

servation gaps analysis is often a major challenge. Here, we used a dated phylogeny including 95.70 % of the Chinese vascular genera and 1,540,695 species distribution records to identify *ex situ* conservation gaps in the tree of life and geographic space in China. We found that at least 41.70 % (12,716 species) of all vascular plant species (30,494 species), including 49.31 % (1715 species) of Chinese endangered species, are conserved in the botanic gardens. The results show that most species in *ex situ* collections are from eastern China and have been housed in botanic gardens in this region, whereas several plant diversity hotpots in the southwestern and northwestern regions are not well represented in *ex situ* conservation; only 12.67 % of the collection capacity of the Chinese botanic gardens is allocated to endangered species; there are 18 phylogenetic clusters of genera absent from the *ex situ* collections and the missing species are mostly from alpine or desert, mainly distributed in the Himalaya-Hengduan Mountains and northern Xinjiang. Therefore, we suggest that more collection capacity of China be devoted to endangered species particularly in the southwestern and northwestern regions. Our study provides quantified resources of targeted inventory and area for future *ex situ* conservation in China, and a fundamental protocol to invest the future achievement of local or global *ex situ* conservation.

**S.148.6 Conservation status assessments of species-rich tropical taxa in the face of data availability limitations: Insights from Sulawesi Begonia**

Daniel C. Thomas¹, Wisnu H. Ardi², Yu H. Chong³, Philip Thomas⁴, Mark Hughes⁴

1 National Parks Board, Singapore Botanic Gardens, Singapore. 2 University of Florida, Institute of Food and Agricultural Sciences, USA. 3 Nanyang Technological University, School of Biological Sciences, Singapore. 4 Royal Botanic Garden Edinburgh, Scotland, UK

The feasibility of conservation and extinction risk assessments of plant species using the criteria outlined by The International Union for the Conservation of Nature (IUCN) Red List can be severely
<figure><img src="image_349.png" /></figure>

compromised by the limited availability of crucial
underlying data. This is particularly true for spe-
cies-rich, tropical plant taxa with a preponder-
ance of microendemics, whose species are often
represented by only a few collections in herbaria
worldwide. *Begonia*, a megadiverse, pantropical
genus (> 2100 species) and characteristic element
in the herb layer of tropical forests, is a prominent
example. The *Begonia* flora of the Indonesian is-
land of Sulawesi, for example, is comprised of 65
species, 62 of which are endemic to the island,
and 51 of which are represented by less than 10
collections in herbaria worldwide. Here we discuss
how, despite of these data limitations, meaning-
ful conservation assessments can be achieved
by integrating (i) extensive fieldwork and field ob-
servations; (ii) herbarium collection locality data;
(iii) data primarily based on remote sensing ap-
proaches including forest landscape integrity,
forest cover loss and land cover categories; (iv)
locality number estimates by evaluating the im-
pact range of plausible threats (e.g. concession
sizes for palm oil plantations and logging, or the
size of large-scale forest fires), and (v) area of
habitat estimations using overlap analyses of el-
evational ranges, forest landscape integrity and
limestone karst distributions. The results indicate
that most Sulawesi *Begonia* species are narrow
endemics whose rainforest and limestone karst
habitats have substantially deteriorated in the last
two decades: 28 species are assessed as Critically
Endangered, 24 as Endangered, six as Vulnerable,
five as Least Concern and two species were con-
sidered Data Deficient. Conservation assessments
of species-rich taxa such as *Begonia*, which in-
clude numerous narrow endemics, are important
for the formulation of effective national-level ac-
tion to prevent further extinction.

S.148.7 Integrating data for
conservation: a use case for
monitoring plant species on
a European scale

Pierre Bonnet¹, Antoine Affouard², Jean-
Christophe Lombardo², Mathias Chouet¹,
Hugo Gresse², Vanessa Hequet¹, Remi
Palard¹, Maxime Fromholtz², Vincent
Espitalier¹, Hervé Goëau¹, Thomas Paillot²,
Benjamin Deneu², Christophe Botella²,

Joaquim Estopinan¹,², César Leblanc¹,²,
Maximilien Servajean³, François Munoz⁴,
Alexis Joly²

1 AMAP, Univ Montpellier, CIRAD, CNRS, INRAE, IRD, Montpellier, France. 2 Inria, LIRMM, Université de Montpellier, CNRS, Montpellier, France. 3 LIRMM, AMIS, Université Paul-Valéry - Montpellier 3, CNRS, Montpellier, France. 4 LIPHY, Univ. Grenoble Alpes, CNRS, Grenoble, France

Human activities are exerting an increasingly pro-
found impact on global biodiversity. There is a
pressing need for a substantial improvement in
our understanding of biodiversity to assist land
managers, and decision-makers in formulating
effective day-to-day strategies for preserving
species and habitats. At the European level, signif-
icant efforts are underway to harness and lever-
age the vast corpus of floristic, environmental, and
remote sensing data to refine our understanding
of vegetation. The Pl@ntNet platform has been set
up to meet this challenge, based on a workflow
at the intersection of citizen science, botany, and
data science. It now enables the automated iden-
tification of over 45,000 plant species using state-
of-the-art deep learning algorithms. The millions
of produced plant observations have contributed
to numerous research and conservation projects,
positioning Pl@ntNet in 2022 as a top-5 data pro-
vider to the GBIF international platform. In this pre-
sentation, we introduce the innovative methods
currently being developed by the Pl@ntNet team
to assist field botanists. Specifically, we discuss
how today's AI technologies allow us to establish
contextualized summaries of plant biodiversity in
specific areas. We discuss advancements in the
analysis of multi-species images commonly gen-
erated during floristic inventories. Additionally, we
showcase results obtained through DeepSDMs
(Species Distribution Models based on deep learn-
ing) for predicting the distribution of species and
indicators characterizing plant biodiversity at very
high resolution. These results are disseminated
through free online maps and services for man-
agers, assisting in the identification of key con-
servation areas. Notably, this work has enabled
map production from local to regional scale, at
50 m resolution. We provide a brief overview of
identified and implemented uses of these results,
demonstrating the various contexts in which these
research findings can be impactful, whether for
education, management, monitoring, or promo-
tion of natural heritage.
# S.149 SYSTEMATICS AND EVOLUTION OF EUPHORBIACEAE

## S.149.1 New insights in the evolutionary relationships of Euphorbiaceae: Implications for classification and understanding character evolution

Kenneth J. Wurdack¹, Otávio Luis M. da Silva²,⁴, Ricarda Riina³, Inês Cordeiro⁴, Lynn J. Gillespie⁵, Warren M. Cardinal-McTeague⁶, Federico Fabriani⁷, Olivier Maurin⁷, Sue Zmarzty⁷, Alexandre Zuntini⁷, Felix Forest⁷, William Baker⁷

1 National Museum of Natural History, Smithsonian Institution, Washington, DC, USA. 2 Instituto de Pesquisas Ambientais, São Paulo, Brazil. 3 Real Jardín Botánico, CSIC, Madrid, Spain. 4 Universidade de São Paulo, São Paulo, Brazil. 5 Canadian Museum of Nature, Ottawa, Ontario, Canada. 6 University of British Columbia, Vancouver, British Columbia, Canada. 7 Royal Botanic Gardens, Kew, Richmond, UK.

Resolving relationships among Euphorbiaceae, the largest and least understood family of Malpighiales, is challenging due to the family's morphological diversity, ancient origins, and pantropical distribution. Molecular phylogenetic studies from the early 2000's discovered (but could not resolve among) seven major lineages of uniovulate Euphorbiaceae and identified widespread conflicts with existing suprageneric classifications. Our phylogenomic results from the Plant and Fungal Trees of Life (PAFTOL) project, which sampled 150 of the ca. 230 genera of Euphorbiaceae using Angiosperms353 target sequence capture, are largely congruent with the prior few-gene studies and offer improved backbone resolution. They support four subfamily-level clades including the previously unclear monophyly of Acalyphoideae, with Erismantheae as its first-diverging lineage. The monophyly of Crotonoideae is also strongly supported, with four major lineages plus a novel, isolated placement for monotypic *Klaineanthus*. The resolution of several critical deep nodes remains problematic, including among subfamily clades, which limits our understanding of the early evolution of major traits such as latex/laticifers, petals, and pol-

len types. In addition, the relationships within Malpighiales of hard-to-place parasitic Rafflesiaceae remain unclear and affect whether Peraceae could be reunited with Euphorbiaceae (as Peroideae). Hippomaneae s.l., the greatest remaining tribal systematics problem, represents a gap in our taxonomic sampling, with only nine of ca. 40 genera sampled. Striking variations in diagnostic morphological traits were observed across clades, including contrasting life history strategies, plant defenses, floral attributes, and specialized reproductive biology (e.g., changes in seed size and dispersal mode). The advances presented here are major steps towards a well-resolved generic phylogeny that would underlie a new classification for Euphorbiaceae and support future studies on the evolution of the astonishing diversity of the family and its biogeographic history.

## S.149.2 Deciphering the drivers behind the “Odd Man Out” pattern using continental African Euphorbiaceae as a case of study

Paloma Ruiz de Diego¹*, Patricia Barberá², Ángela Aguado-Lara¹, Irene Villa-Machío¹, Tamara Villaverde³, Ricarda Riina¹, Isabel Sanmartín¹

1 Real Jardín Botánico, CSIC, Madrid, Spain. 2 Missouri Botanical Garden, St. Louis, Missouri, USA. 3 Universidad Rey Juan Carlos, Madrid, Spain

The “Odd-Man-Out” pattern describes the lower plant diversity observed in continental tropical Africa compared to other tropical regions. We examine long-standing hypotheses behind this pattern by adopting a model-clade approach that combines in-depth knowledge of small-scale clade studies with the power of family-wide meta-analysis. We focus on 31 genera of Euphorbiaceae (~550 species), grouped into 19 clades. Our workflow involves the revision of each genus’ alpha-taxonomy and the compilation of information about species traits, distribution, and ecology; the generation of phylogenetic
<figure><img src="image_350.png" /></figure>

ically informative sequence data from 431 low-copy
nuclear genes, obtained using target sequencing
(Hyb-Seq) and a taxon-specific bait kit; and final-
ly, the integration of the assembled trait, ecological,
biogeographic, and phylogenomic data to explore
biological processes working at the clade-level, and
general drivers acting clade-wide on Afrotropical
lineages. Based on ~78% of the target species and
all focal genera, we produced the first phylogenom-
ic time-tree for the African Euphorbiaceae, includ-
ing representatives of the three subfamilies Aca-
lyphoideae, Crotonoideae, and Euphorbioideae. An
ancient stem age (54-26 Ma) was inferred for the
smallest genera (less than 10 species), predating the
global climate cooling that followed the Paleogene.
Diversification rate analyses using episodic birth-
death models and an empirical strategy to account
for missing species revealed a negative diversifica-
tion rate between 23 and 5 Ma, which corresponds
with a period of severe aridification in Africa. Paleo-
climate niche projections showed climatically suit-
able areas across southern and eastern Africa for
many genera, which disappeared after the Pliocene.
Taken together, this evidence points to climate-driv-
en extinction as the most likely process to explain
the Odd-Man-Out pattern in African Euphorbiaceae.
Frequent dispersal from Madagascar was an ad-
ditional process involved in shaping diversification
patterns, as revealed by an 80%-complete species
tree for the mega-diverse genus Croton.

S.149.3 Inflorescence
and floral morphology
in the tribe Crotoneae:
Implications for the
systematics and evolution

Pakkapol Thaowetsuwan¹, Ricarda Riina²,
Louis P. Ronse De Craene³

1 Department of Biology, Faculty of Science, Silpa-korn University, Nakhon Pathom, Thailand. 2 Real Jardín Botánico, CSIC, Madrid, Spain. 3 Royal Bo-tanic Garden Edinburgh, Edinburgh, UK.

The tribe Crotoneae comprises six genera *Sandwithia*, *Sagotia*, *Acidocroton*, *Astraea*, *Brasiliocroton* and the mega-diverse *Croton*. However, there is no prior study compares floral morphology across all six genera except in few species of *Astraea* and *Croton*. To un-derstand the floral diversity in this tribe, inflorescenc-es and flowers from at least one species from each genus were examined with various techniques, e.g-

light microscopy, scanning electron microscopy, resin
sectioning and micro-CT. Our investigation revealed
significant floral diversity among all genera. Our in-
vestigation further identified several synapomorphies
across the Crotoneae tribe, including the exclusive
presence of staminate flowers on the upper portion of
the inflorescence, the presence of more than 10 sta-
mens in staminate flowers, and the reduction of pet-
als in pistillate flowers. Furthermore, synapomorphies
of each subclade within the Crotoneae were identi-
fied. The *Sagotia-Sandwithia* clade members have
botryoid inflorescences, simple trichomes, petals ex-
ceeding the size of sepals at the anthesis, and outer-
most stamens alternating with petals. In contrast, the
*Acidocroton-Astraea-Brasiliocroton-Crotonclade* ex-
hibits racemose inflorescence, stellate trichomes with
diverse forms, and outermost stamens positioning op-
posite petals. Notably, *Acidocroton*, despite belonging
to this clade, exhibits some unusual characters that
diverge from the typical patterns observed within the
group. Our investigation also explored and discussed
the inflorescence and floral morphologies of the Cro-
toneae compare to the tribe *Jatropheae* and others
groups in the subfamily Crotonoideae. Therefore, our
study highlights the remarkable heterogeneity pres-
ent among members of this tribe and provides valu-
able insights into the key morphological features that
define the entire group. Further research is needed to
fully elucidate the complex evolutionary relationships
and adaptive significance of floral characteristics
within the Crotoneae.

S.149.4 A revised generic
classification of Tragiinae
including the subdivision of
Tragia (Euphorbiaceae tribe
Plukenetieae)

Warren Cardinal-McTeague¹,², Kenneth Wurdack³, Lynn Gillespie²

1 Department of Forest & Conservation Sciences, University of British Columbia, Vancouver, Canada.
2 Research & Collections Division, Canadian Museum of Nature, Ottawa, Canada.
3 Department of Botany, Smithsonian Institution, Washington, USA

Plukenetieae subtribe Tragiinae (Acalyphoideae) is
a pantropical and subtropical lineage of ~14 genera
and ~200 species of primarily twining vines charac-
terized by their small unisexual flowers with diverse
pistillate and androecial morphology, exception-
al pollen morphology (including trends towards
<figure><img src="image_351.png" /></figure>

aperture reduction and loss), and stinging hair
defenses. *Tragia* (~160 species) is one of the larg-
er genera of Euphorbiaceae and has a complex
sectional classification that until recently included
several small genera that are now recognized as
distinct (e.g., *Bia*, *Ctenomeria*, *Monadelpha*, *Zucker-
tia*). It was hypothesized that several more of the
sections of *Tragia* could be resurrected as genera
but only upon the careful assessment of molecu-
lar and morphological data. Using Bayesian phy-
logenetics on a concatenated dataset of nuclear
ribosomal (ETS, ITS), nuclear low-copy (TEB), and
plastid (matK, ndhF) DNA, we produced a robust
and well-resolved phylogeny for Tragiinae. *Tragia* is
strongly supported as paraphyletic with many sub-
clades that could be recognized as distinct genera.
Here, we outline our revised generic classification
for Tragiinae, which circumscribes genera by a
combination of floral morphology (specifically pis-
tillate and androecial morphology), inflorescence
structure, well-defined biogeographic distributions,
and palynological evidence.

S.149.5 Shining light on
a Boreotropical clade:
evolution and diversification
of Euphorbia subgenus
Esula

Irene Masa-Iranzo¹, Isabel Sanmartín¹,
Božo Frajman², Andrea S. Meseguer¹,
Ricarda Riina¹

1 Real Jardín Botánico, CSIC, Madrid, Spain. 2 Uni-
versity of Innsbruck, Innsbruck, Austria

Euphorbia subgenus *Esula* Pers. is one of the four lineages of the megadiverse genus *Euphorbia*, and comprises over 485 annuals or perennials, including dendroid shrubs and pencil-stemmed succulents. While the group is primarily a northern temperate radiation it is most diverse in the Irano-Turanian and Mediterranean regions, but taxa also occur in Africa, Asia, and the temperate New World. We assembled the largest taxon sampling of *E. subg*. *Esula* to date (322 spp.), representing its entire geographic range. We updated previous phylogenetic analyses, which confirmed the current sectional classification of the group. We also estimated divergence times and re-constructed ancestral ranges using Bayesian meth-ods. This framework allowed us to characterize the magnitude of extinction and speciation events that

have shaped the extant diversity and present distri-
bution of this subgenus. We also explored the influ-
ence of changes in life form/history in the diversifi-
cation and the present altitudinal ranges of *E. subg*.
*Esula*. Our results show the divergence of *E. subg*. *Es-
ula* from its sister clade (the three other subgenera)
c. 47 Mya, and diversification within this group ca. 41
Mya Biogeographic analyses suggest an ancient or-
igin of the group in the Western Palearctic, where it
steadily diversified over millions of years, before the
subgenus dispersed to other regions recently. The
group underwent parallel events of recent radia-
tions coupled with life history changes, from annual
to perennial. Our findings suggest a positive correla-
tion between perenniality and high elevations. These
results support that the recent rapid diversification
of *E. subg*. *Esula* is associated with the evolutionary
shift to perennial life forms, which allowed coloniza-
tion of montane habitats and global range expan-
sion beyond the Western Palearctic.

S.149.6 The almighty Ricinus:
a phylogenomic study
sheds new light on the
historical domestication
and invasive potential of
castor bean

Tamara Villaverde¹, Irene Villa Machío²,
Nicolás Echarren Lucendo¹, Esther García
Guillén³, Juli Caujapé-Castells⁴, Isabel
Sanmartín³, Ricarda Riina³

1 Conservation and Biodiversity Area, Universidad
Rey Juan Carlos, Madrid, Spain. 2 Missouri Botani-
cal Garden, St. Louis, MO, USA. 3 Real Jardín Botáni-
co (CSIC), Madrid, Spain. 4 Jardín Botánico Canario
“Viera y Clavijo” (CSIC), Las Palmas de Gran Ca-
naria, Spain

Ricinus communis is an economically and culturally
important species. Today, it is used in the automo-
tive, cosmetic, and pharmaceutical industries, as
well as an ornamental plant. In the last decades, the
species has become an exotic invasive species in
many areas of the world. We aimed to characterize
the genetic structure of *R. communis* in its native and
invaded areas using genomic data. Our sampling
included specimens worldwide, with a special focus
on naturalized populations, and also whole-genome
data from previously published studies. Capture
success using HybSeq was high in samples collect-
ed in the early twentieth century. We also managed
to sequence one of the oldest specimens ever in-
cluded in a phylogenomic analysis, a sample col-
lected by A.J. Cavanilles in Valencia (Spain) in 1792.
Introgression of populations was detected, although
unique genotypes were found in the putative na-
tive range of *Ricinus* (Ethiopia and Somalia). Our
results revealed frequent events of admixture and
introgression between regions of the world that are
supported by historical herbarium records in Europe.

This demonstrates the cultivation and naturalization
of *Ricinus* in Europe at least during the Great Age of
Exploration. Herbariomics and sampling of natural-
ized populations have uncovered a wide genomic
breath, unseen in previous studies. *Ricinus* climatic
niche shows that it occupies areas with novel cli-
mates, not present in its native range, indicating a
wide ecological plasticity that might have facilitated
its naturalization in all continents.

# S.150 POALES: FROM ADDRESSING GLOBAL SCALE QUESTIONS TO UNRAVELING THE EVOLUTIONARY SECRETS OF NEGLECTED FAMILIES

## S.150.1 Cyperus margaritaceus and its relatives: How many species are there?

Martin Xanthos¹, Isabel Larridon¹,², Simon J. Mayo¹

1 Royal Botanic Gardens, Kew, Richmond, Surrey, UK.

2 Ghent University, Department of Biology, System-
atic and Evolutionary Botany Lab, Gent, Belgium

The *Cyperus margaritaceus-niveus* complex (*Cyperaceae*) is a group of ten tropical species (*C. karlschumanii*, *C. kibweanus*, *C. ledermannii*, *C. margaritaceus*, *C. niveus*, *C. nduru*, *C. obtusiflorus*, *C. somaliensis*, *C. sphaerocephalus* & *C. tisserantii*) from sub-Saharan Africa & Madagascar united by the combination of a capitate inflorescence, white-yellow glumes and swollen bulb-like bases. Recent molecular studies in the *C4 Cyperus* clade, have shown that some members of the complex form a monophyletic group sister to the rest of the *C4 Cyperus* species, however regional floras have been unable to reach a consensus on inter-species relationships, presenting differing opinions on the circumscriptions of these taxa. In this study, we use multivariate morphometric analyses - Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA) and Classification and Regression Tree Analysis (CART) - to test the robustness of the species circumscriptions presented in these floras. Unlike flo-

ra accounts which only use a partial subset of the
taxa, we use all species represented in the complex
from across their entire geographical range. *Cype-
rus kibweanus* was not considered due to lack of
material. The analyses show that eight morphospe-
cies are recognised for the LDA, and six morphos-
pecies are recognised for CART. Both PCA and LDA
showed varying degrees of overlap in nine of the ten
taxa, with no single group clearly separating in mul-
tivariate space. Notable results include: 1) the LDA
cross-validation showing *C. margaritaceus* to form
a robust entity despite its overlapping with the other
taxa, and 2) the failure of *C. niveus* to form a distinct
entity in both LDA cross-validation and CART. The
computational approach attempted here is a useful
tool to add to traditional taxonomic methods in re-
solving other species complexes in the Cyperaceae.

## S.150.2 Unprecedented variation pattern of plastid genomes and the potential role in adaptive evolution in Poales

Hong Wu¹,², De-Zhu Li¹, Peng-Fei Ma¹

1 Germplasm Bank of Wild Species, Yunnan Key
Laboratory of Crop Wild Relatives Omics, Kunming
Institute of Botany, Chinese Academy of Sciences,
Kunming, Yunnan, China. 2 University of Chinese
Academy of Sciences, Beijing, China
The plastid is the photosynthetic organelle in plant cell, and the plastid genomes (plastomes) are generally conserved in evolution. As one of the most economically and ecologically important order of angiosperms, Poales was previously documented to exhibit great plastomic variation as an order of photoautotrophic plants. We acquired 93 plastomes, representing all the 16 families and five major clades of Poales to reveal the extent of their variation and evolutionary pattern. Extensive variation including the largest one in monocots with 225,293 bp in size, heterogeneous GC content, and a wide variety of gene duplication and loss, were revealed. Moreover, rare occurrences of three inverted repeat (IR) copies in angiosperms and one IR loss were observed, accompanied by short IR (sIR) and small direct repeat (DR). Widespread structural heteroplasmy, diversified inversions and unusual genomic rearrangements all appeared in Poales, occasionally within a single species. Extensive repeats in the plastomes were found to be positively correlated with the observed inversions and rearrangements. The variation all showed a 'small-large-moderate' trend along the evolution of Poales, as well as for the sequence substitution rate. Finally, we found some positively selected genes, mainly in C4 lineages, while the closely related lineages of those experiencing gene loss have already undergone more relaxed purifying selection. The variation of plastomes in Poales may be related to its successful diversification into diverse habitats and multiple photosynthetic pathway transitions. Our order-scale analyses revealed unusual evolutionary scenarios for plastomes in the photoautotrophic order of Poales and provided new insights into the plastome evolution in angiosperms as a whole.

### S.150.3 Global dominance in open and closed habitats is driven by unique traits in the Poales

Tammy L. Elliott¹,², Daniel Spalink³, Isabel Larridon⁴,⁵, Marcial Escudero⁶, Jan Hackel⁴, Russell L Barrett⁷, Santiago Martín-Bravo⁸, José Ignacio Márquez-Corro⁴,⁸, Carolina Granados Mendoza⁹, Aluoneswi C Mashau¹⁰, Katya Romero Soler⁹, Daniel A. Zhigila¹¹, Caroline Oliveira Andrino¹², Ana Carolina Galindo da Costa¹³, Maria S Vorontsova⁴, Karen L Wilson⁷, A Muthama Muasya²

¹ Masaryk University, Brno, Czech Republic. ² University of Cape Town, Cape Town, South Africa. ³ Texas A&M University, Texas, USA. ⁴ Royal Botanic Gardens, Kew, UK. ⁵ Ghent University, Gent, Belgium. ⁶ Universidad de Sevilla, Seville, Spain. ⁷ Australian Institute of Botanical Science, New South Wales, Australia. ⁸ Universidad Pablo de Olavide, Seville, Spain. ⁹ Universidad Nacional Autónoma de México, Mexico City, Mexico. ¹⁰ South African National Biodiversity Institute, Pretoria, South Africa. ¹¹ Gombe State University, Gombe, Nigeria. ¹² Universidade de Brasília, Brasília, Brazil. ¹³ Instituto Tecnológico Vale Desenvolvimento Sustentável, Belém, Brazil

Poales, one of the most species-rich orders of plants, often characterise open habitats, enabled by unique suites of traits. We test the hypothesis that key life form traits (photosynthetic system, annual/perennial, insect/animal pollination, epiphyte/non-epiphyte, presence of silica) diverge in different lineages at distinct times and places, leading to spatiotemporal heterogeneity in the diversification of families and the assembly of open habitats. We sampled 42% of Poales species and obtained taxonomic and biogeographic data from the World Checklist of Vascular Plants database, which was combined with trait data scored by taxonomic experts. A dated phylogeny of Poales was constructed using phylogenomic and phylogenetic data. We integrated spatial phylogenetics with regionalization analyses, historical biogeography, ancestral state estimations and models of contingent evolution. Diversification in Poales and assembly of open and closed habitats results from dynamic evolutionary processes that vary across lineages, time, space and traits. Parallel patterns of habitat and trait transitions are evident in the species-rich Poaceae and Cyperaceae families, yet other smaller families display unique evolutionary trajectories. Our results suggest that flexibility in key traits, which is displayed in the most species-rich lineages of Poales, might be an important adaptation allowing transitions between open and closed habitats.

### S.150.4 Evolution of holocentricity in hyperids

Andrea Pedrosa-Harand¹, Yennifer Mata-Sucre¹,², Yhanndra Dias¹,³, Lucas Costa¹, Mariela A. Sader⁴, Mariana Báez⁵, Thaíssa Boldieri de Souza⁶, Letícia Maria Parteka⁶, Gokilavani Thangavel², Yi-Tzu Kuo³, Veit Schubert³, Jörg Fuchs³, Christopher E. Buddenhagen⁷, André Vanzela⁶, Gustavo Souza¹, André Marques², Andreas Houben³
<figure><img src="image_352.png" /></figure>

1 Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Federal University of Perú, Recife-PE, Brazil. 2 Max Planck Institute for Plant Breeding Research, Cologne, Germany. 3 Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Germany. 4 Instituto Multidisciplinario de Biología Vegetal, Universidad de Córdoba-CONICET, Córdoba, Argentina. 5 Plant Breeding Department, University of Bonn, Bonn, Germany. 6 Laboratório de Citogenética e Diversidade de Plantas, Departmento de Biologia Geral, Universidade Estadual de Londrina, Londrina-PR, Brasil. 7 AgResearch, Agro-ecology, Ruakura, New Zealand

While most species have monocentric chromosomes with a regionally restricted centromere, holocentromeres show centromere activity along the entire chromosome. Holocentromeres evolved independently at least 14 times across plant and animal groups. Among plants, the cyperid clade (Poales) comprises the highest number of species with holocentric chromosomes. However, based on recent findings, the transition from mono-to-holocentricity occurred in this clade multiple times, because lineages with mono- or holocentric chromosomes exist. Independent transitions to holocentricity resulted in different adaptations of the centromere and genome structures in these different groups of species, giving insights into variable centromere plasticity and function. We review our recent findings regarding the centromere organization and the role of different classes of repeats in chromosome evolution in monocentric and holocentric Thurniaceae, Juncaceae and Cyperaceae species, and discuss the diversification of this group from a cytogenomic perspective.

## S.150.5 Homology-based approach in assessing morphological diversity of Restionaceae

Constantin I. Fomichev¹,², Terry D.

Macfarlane³, Barbara G. Briggs⁴, Dmitry D.

Sokoloff¹

1 Lomonosov Moscow State University, Moscow, Russia. 2 Shenzhen MSU-BIT University, Shenzhen, China. 3 Western Australian Herbarium, Perth, Australia. 4 National Herbarium of New South Wales, Sydney, Australia

Despite great taxonomic diversity and a significant role in the vegetation of Australia and South Africa, Restionaceae remain quite difficult in genus

and species identification for non-specialists. The problem is at least partly caused by the insufficient amount of morphological data on Restionaceae based on homology instead of a descriptive approach. Well-defined morphological characters can indicate the accurate similarities and differences of taxa and are especially significant for systematics. Restionaceae are well-known for their commonly short and inconspuous leaf lamina. To date, identification of Restionaceae commonly ignores some leaf characters, e.g., fusion of sheath edges, details of leaf sheath to lamina transition, and lamina morphology. Our analysis of the leaf charters of Australian Restionaceae indicates the taxonomical significance of foliar morphology. For example, we used the occurrence of a long leaf ligule (up to 1.5 cm) as a new character to distinguish species in *Anarthria* (a genus with unusually well-developed leaf lamina). We revealed, also using molecular data and micromorphology, that the commonly accepted species, *Anarthria gracilis*, represents a species complex comprising three distinct species. We present and analyse a new data set on key characters of leaf morphology, including fine details of sheath to lamina transition, for all genera of Australian Restionaceae. A case study of *Leptocarpus denmarkicus* provides an example of new knowledge on inflorescence morphology. We show that the female inflorescence unit in *L. denmarkicus* is a double rather than a simple spike. Spirally arranged glumes represent pherophylls bearing reduced lateral spikelets. Each true spikelet has two bracts, of which one is fertile and subtends a flower. Analogous situations may occur in other Restionaceae. Our aim is to produce a homology-based compendium of morphological character evolution in Restionaceae and to assess the adaptive value of taxonomic characters.
# S.151 EVOLUTION AND FUNCTION OF CONVERGENT FLORAL PHENOTYPES. SESSION 2

## S.151.1 Selection surfaces driven by different pollinators

Ethan Newman¹², Allan Ellis¹, Bruce Anderson¹

1 Stellenbosch University, Stellenbosch, South Africa.

2 Rhodes University, Grahamstown, South Africa

Pollinators are important drivers of floral divergence and speciation in plants. Indeed, *Tritoniopsis revoluta* populations appear to have diverged in response to different long proboscid fly pollinators, as evidenced by closely matched floral tube lengths and pollinator proboscis lengths. But in addition to long proboscid flies, most populations are also visited by solitary bees with short proboscides. Here we investigate how different functional pollinator groups affect pollen receipt across a wide range of floral tube length phenotypes. We experimentally increased floral tube length variance in two populations by translocating short and long tubed plants from elsewhere. We then counted the number of pollen grains deposited on virgin stigmas after single visits by either bees or long proboscid flies. We demonstrate that these distinct functional groups of pollinators have very different effects on pollen movement. More specifically, although bees may be important pollinators in these systems, they are unlikely to impose strong selection on floral tube length. In contrast, the morphological fit between the proboscides of long tongued flies and the corolla tubes of *T. revoluta* flowers appears to be a key feature affecting pollen transfer. This study explains why the tube lengths of *T. revoluta* are apparently adapted to flies rather than bees, even when both are present.

## S.151.2 Convergent evolution of floral visual signals via different optical mechanisms

Casper J. van der Kooi¹

1 University of Groningen, The Netherlands

Flower colour is a key enabler for plants to attract animal pollinators. The colours of flowers are generated by two basic optical principles: wavelength-specific absorption of light by floral pigments and reflection/scattering of incident light by floral structures (e.g., cell walls, starch granules, epidermal surface). We study the evolution of flower colouration using optics, anatomical methods and behavioural experiments with insects. Sampling different Angiosperm groups that are characterised by independent transitions between pollinators with different visual systems, we found that the optical properties of flowers evolve to maximise visibility to pollinators in four complementary ways. First, the type of pigment, which determines a flower's overall hue, is tuned to the spectral sensitivity of pollinators. For example, reflection of ultraviolet, blue, yellow or red light is linked to whether the prime pollinator can perceive this colour. Second, the amount of pigment, which determines the spectral filtering of the scattered light, is optimised to yield high colour contrast. Low pigment amounts yield pale colours, intermediate amounts vivid colours, and high amounts dull colours. Third, the amount of scattering ("brightness") of flowers is determined by the number and inhomogeneity of cell layers. Flower brightness increases upon a switch from diurnal to nocturnal pollination, and this is caused by modifications of both flower thickness and cell structure. Fourth, the epidermal surface determines the glossiness (specularity) of a flower. In specific taxa, such as sexually deceptive orchids and buttercups, very flat and specular surfaces create a brilliant visual effect. Behavioural experiments confirm that bees use surface gloss as a visual cue. In most species, however, cone-shaped epidermal cells annihilate surface gloss and so increase the absorption by pigments and enhance a flower's visibility. Together, our findings show that floral visual signals converge via different, complementary optical mechanisms to maximise visibility to their pollinators.