bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gene Flow Between Introduced and Native Eucalyptus Species: Morphological Analysis of Tri-Species and Backcross Hybrids Involving E. nitens
Authors: Barbour C. , Potts B. M. , Vaillancourt R. E. 
Published: October 2017

SummaryMorphometric analyses were conducted on second-generation tri-species and backcross hybrids in Eucalyptus. These hybrids were all produced using pollen from two E. nitens x cordata F1 hybrids and controlled pollination techniques. Tri-species hybrids were created with E. gunnii, E. ovata and E. viminalis as females, while backcrosses were produced with E. cordata. Multivariate analysis of seedling characteristics indicated that eighty percent of the backcross hybrids fell within the morphological range of E. cordata. All three cross combinations of the tri-species hybrids were biased away from E. nitens and towards their maternal parent and E. cordata. The inclusion of data for first-generation (F1) hybrids between the pure parental species in the current work showed the F1’s to be easily distinguishable from pure species, compared to second-generation hybrids. The use of morphology for detecting second-generation hybridisation involving exotic plantation species and native eucalypt populations will therefore be unreliable, and identifies a need for preventing second-generation hybrids from establish in the wild. The current work, nevertheless, provides further demonstration of the effectiveness of morphological identification of F1 hybrids. The easy recognition of F1 hybrids will be useful in identifying sites and species at risk of exotic gene flow and enable the development of weeding programs that focus on removing exotic hybrids in the wild.
Characterization of a Suite of 40 EST-derived Microsatellite Markers For Use in Sitka Spruce (Picea sitchensis (Bong.) Carr)
Authors: A’Hara S. W. , Cottrell J. E. 
Published: October 2017

Abstract
This paper describes 40 novel, data-mined, polymorphic microsatellite loci for use in a QTL association study in Sitka spruce. Publicly available EST sequences of Picea in Genbank were searched in silico for simple sequence repeat (SSR) motifs, principally dinucleotide microsatellites, and PCR primers were designed to flank these regions. PCR amplification was carried out in the progeny of a full-sib family to test simple Mendelian inheritance. For further characterization, the amplification products of Sitka spruce material from unrelated trees were assessed to determine the potential of these loci for population genetic studies. These polymorphic markers therefore represent a valuable tool-kit both for establishing a molecular map of this species and for Picea genetic population studies.
High Levels of Outcrossing in a Family Trial of Western Australian Sandalwood (Santalum spicatum)
Authors: Muir K. , Byrne M. , Barbour E. , Cox M. C. , Fox J. E. D. 
Published: October 2017

AbstractThe mating system of Western Australian sandalwood (Santalum spicatum) was investigated in seed collections from a family trial. The mean outcrossing rate was high (95.2%) although there was variation among families and one family showed particularly low outcrossing, high bi-parental inbreeding and high correlated paternity. Variation in flowering time between this family and others in the trial was the most likely cause of the high inbreeding and low number of fathers contributing to the seed crop in trees from this family. The high level of outcrossing in the rest of the families indicated that S. spicatum has a preferentially outcrossed mating system, but that it is capable of selfing when conditions are unsuitable for outcrossing. The seedling progeny showed no influence of inbreeding on seedling height at 4 months. Analysis of genetic diversity revealed high levels of genetic diversity have been captured in the seed crop from the trial, and this diversity is comparable to that identified in a previous study of natural populations from throughout the range of the species. These results indicated that production of seed through seed orchards will be a successful means of deployment of breeding gains in the species, however it is essential to ensure overlap in flowering times among different families planted in a seed orchard.
Realized Genetic Gains of Rust Resistant Selections of Slash Pine (Pinus elliottii var. elliottii) Planted in High Rust Hazard Sites
Authors: Vergara R. , White T. L. , Huber D. A. , Schmidt R. A. 
Published: October 2017

SummaryRealized gains from selection for resistance to the fungal disease fusiform rust caused by Cronartium quercuum f. sp. fusiforme were estimated using data from five field trials planted on large rectangular plots in high rust-hazard sites. These five realized gain trials, planted as a Best Management Practices study (BMP), compared resistant and susceptible mixtures of families from the first-generation breeding population of slash pine (Pinus elliottii var. elliottii Engelm.) in southeastern North America. Analyses of variance (Proc Mixed using REML in SAS), conducted to test the significance of realized gains and interactions contrasting resistant with susceptible seedlots, detected important and highly significant realized gains in both rust resistance and mid-rotation yield. Significant gains were obtained for rust resistance at age 5 and stand yield at age 16 with high stability across sites and across silvicultural treatments, indicating that gains in rust resistance and the associated influence on gains in stand yield were consistent under many environmental conditions. Additionally, the values of realized gains in stand yield steadily increased with age, primarily due to increased rust associated mortality with age in the susceptible material. The 25% realized gain for rust resistant material compared to rust susceptible material obtained at age 16 was conservatively extrapolated to a 25-year-old rotation-age gain of 51.4 m3ha-1(735 feet3acre-1) in inside-bark volume.
Variability of Cortex Terpene Composition in Cupressus sempervirens L. provenances grown in Crete, Greece
Authors: Gallis A. T. , Doulis A. G. , Papageorgiou A. C. 
Published: October 2017

AbstractThe terpene composition of twigs in 106 trees from 6 provenances of Cupressus sempervirens L. grown in the island Crete of Greece was determined by GLC-MS analysis. The aim was to investigate the utility of cortex terpene composition to study the genetic variation between cypress provenances. Twenty nine compounds were detected in cortex resin of all trees, twenty one of which identified. The major constituents were cedrol, α-pinene, 3-δ-carene and α-terpinyl acetate. A cluster analysis based on the amounts of the four evaluated compounds classified all the trees in five chemotypes. The chemotype pattern for every provenance was determined. Based on distribution of chemotypes two main groups of provenances can be suggested.
Evaluation of Early Rooting Traits of Eastern Cottonwood That Are Important For Selection Tests
Authors: Kovacevic B. , Guzina V. , Kraljevic-Balalic M. , Ivanovic M. , Nikolić-Đorić E. 
Published: October 2017

AbstractVegetative propagation of superior genotypes via stem cuttings depends on their development of strong vigorous root system. Fourteen characters of cutting rooting were examined in multiannual tests with 12 genotypes of eastern cottonwood (Populus deltoides BARTR. EX MARSH) in course of evaluation of their utilization in selection tests. Variability and relationship among examined characters, and cutting survival rate were analyzed according to contribution of expected variances to the total variance and results of principal component analysis, stepwise regression analysis and path analysis. Along with total number and length of first-order roots, the characters that are regularly used in the assessment of rooting potential, our results signify dynamic shoot growth and uniform arrangement of roots on cutting at the beginning of growing period. The best results were obtained for shoot height at the second half of May. A rapid and non-destructive way of shoot characters’ measurement allows testing of larger material and prevents losses in propagation material of interesting genotypes. Alone or together with total root number and length these alternative characters could be used for the improvement of selection tests and procedures for cultivar technology design.
An Evaluation of Selection for Volume Growth in Loblolly Pine
Authors: Sherrill J. R. , Mullin T. J. , Bullock B. P. , Mckeand S. E. , Purnell R. C. , Gumpert M. L. , Isik F. 
Published: October 2017

Abstract
Total inside-bark volume is the most important selection criterion for productivity in tree breeding programs in the Southeastern U.S. Tree breeders typically estimate total inside-bark volume based on outside-bark diameter at breast height and total height without accounting for stem taper or bark thickness. To make a direct determination of total inside- and outside-bark volume, a loblolly pine (Pinus taeda L.) open-pollinated family trial replicated with cultural treatments of weed control and fertilization was measured. This direct measurement was compared to typical volume estimates. In this trial, approximately 40 individuals from each of 25 open-pollinated first- and second-generation families were destructively sampled in the 13th growing season. Selection for volume using a combined-variable (diameter2 * height) equation was found to be highly effective for making volume gain. There was a high correlation between estimated and directly-measured total inside-bark volumes (0.99). Bark thickness and stem taper had low importance for stem volume selection. There was a positive genetic correlation between bark thickness and diameter at breast height (0.66). This indicates that selection for larger diameters may produce individuals with thicker bark, which may eventually affect total inside-bark volume estimates.
Construction of a Populus tremuloides Michx. BAC library
Authors: Fladung M. , Kaufmann H. , Markussen T. , Hoenicka H. 
Published: October 2017

AbstractWe have constructed an aspen (Populus tremuloides Michx., line Turesson141) BAC library containing 55,296 clones in total. A random sampling of 86 BAC clones indicated an average insert size of 76 kb with a range of 20 to 160 kb. Twelve percent of the BAC clones in the library have an insert size larger than 100 kb. Based on an estimated genome size for Populus of 500 Mbp, library coverage is about 8 haploid genome equivalents. This library will be screened using AFLP marker identified before co-segregating with gender in a P. tremula x P. tremuloides progeny, where Turesson141 was the male parent.
Comparison of Genetic Structure Assessed by Amplified Fragment Length Polymorphism and Retrotransposon-based Sequence-specific Amplification Polymorphism for Portuguese Populations of Pinus pinea L.
Authors: Evaristo I. , Santos S. , Tenreiro R. , Costa R. 
Published: October 2017

AbstractIn order to assess genetic diversity within and among populations of Pinus pinea L. (stone pine), seven Portuguese populations originating from three Provenance Regions were selected and genotyped using two marker systems. We compared the genetic variation of these populations using retrotransposon-based sequence-specific amplification polymorphism (SSAP) and amplified fragment length polymorphism (AFLP). In total, 105 trees were screened with three primer enzyme combinations (PEC), producing 232 SSAP and 132 AFLP loci. Where SSAP yielded approximately twice-the number of polymorphic fragments compared to AFLP. Differentiation was slightly higher for SSAP, than for AFLP (FST = 0.105 for SSAP and 0.074 for AFLP), and both significantly different from zero, P < 0.01. The levels of average genetic diversity within-population found with the two types of marker were not significantly different between SSAPs and AFLPs (26.6% and 22.8%, respectively). The populations that displayed the highest and lowest genetic diversity scores were the same for both markers, and only two populations had significantly different He estimates. The neighbor-joining tree based on the Nei’s genetic distance displayed some geographic pattern. With the AFLP markers the populations grouped according to the provenance regions where they were sampled, resulting in one well supported cluster with the Southern populations, but with SSAP the pattern was not so coherent. In this study SSAP generated more polymorphic fragments and higher estimates of genetic diversity than AFPL did, due, probably, to the higher mutation rate of retrotransposition relative to base mutation. Nevertheless, congruence was found between estimates obtained with both markers, which is very interesting, for, in general, SSAP markers have lower costs compared to AFLPs, and they might be an interesting alternative marker system, when higher resolution is requested.
Crossability Between Wild (Malus sylvestris) and Cultivated (M. x domestica) Apples
Authors: Larsen A. S. , Jensen M. , Kjær E. D. 
Published: October 2017

AbstractMalus sylvestris, a native fruit tree of Europe, is believed to be threatened by hybridization with the omnipresent cultivated apple (Malus x domestica). In the present study a series of controlled crossings were carried out in order to establish whether M. sylvestris can hybridize with its near relative, M. x domestica. By looking at fruit set, seed production, germination percentages, and development of seedlings following inter- and intraspecific crossings, no indication of neither pre- nor postzygotic barriers to hybridization between the two species was found. This can have important implications for management of the genetic resources of M. sylvestris.
Provenance by Site Interaction of Pinus densiflora in Korea
Authors: Kim In-Sik , Kwon Hae-Yun , Ryu Keun-Ok , Choi Wan Yong 
Published: October 2017

Abstract
Thirty-six provenances of Pinus densiflora were evaluated for stability and adaptability for height growth at 11 test sites in Korea. The data were obtained from measurements at age 6 and analyzed using linear regression model and AMMI (additive main effect and multiplicative interaction) model. There was significant provenance by site interaction effect (p < 0.011). The interaction term explained 7.1% of total variation. While the regression model accounted for 15.8% of GxE interaction term, the AMMI model accounted for 74.9% with four PCA values. Most of the provenances were not significantly different from the unity (b =1.0), except for Inje (1), Jungsun (4), Bongwha (5), Koryung (26), Hamyang (30) and Seoguipo (36). Adaptability of provenances to the test sites was estimated with mean height growth and first AMMI component scores (IPCA 1). Inje (1), Bongwha (5), Taean (20) and Seoguipo (36) were specifically adapted to the high yielding environments. Considering the first and second AMMI components (IPCA 1 and IPCA 2, respectively) scores, Whachun (2), Samchuk (10), Joongwon (14) and Buan (29) provenances were more stable than others. The implication of GxE interaction was discussed in view of seed transfer and delineation of seed zones.
Molecular Cloning and Characterization of a cDNA Encoding Sedoheptulose-1,7-bisphosphatase from Mulberry (Morus alba var. multicaulis)
Authors: Ji X. , Gai Y. , Ma J. , Zheng C. , Mu Z. 
Published: October 2017

Abstract
A full-length cDNA encoding sedoheptulose-1,7-bisphosphatase (SBPase; EC 3.1.3.37) was cloned from mulberry (Morus alba var. multicaulis) by rapid amplification of cDNA ends (RACE). The cDNA consisted of 1,527 nucleotides with an open reading frame (ORF) of 1,179 nucleotides encoding a 393 amino acid protein of approximately 42.6 kDa. Sequence comparison analysis showed that mulberry SBPase (MSBPase) had high homology to other plant counterparts. Phylogenetic and molecular evolutionary analysis revealed that MSBPase fell into plant SBPase group. Moreover, SBPase and fructose-1,6-bisphosphatase (FBPase; EC 3.1.3.11) shared 28-32% identical residues, suggesting that the two enzymes originated from the same evolution branch. Molecular modeling indicated that each subunit of MSBPase was composed of α-helices and β-sheets joined by turns and loops, and folded into a structure of hexahedron shape which was very similar to FBPase.
Short Note: Root Restriction Hindered Early Allometric Differentiation Between Seedlings of Two Provenances of Canary Island Pine
Authors: Climent J. , Alonso J. , Gil L. 
Published: October 2017

AbstractBased on the optimal partitioning theory, the comparative assessment of seedling allometry is a common task in retrospective genetic tests and early testing of forest reproductive material. Our hypothesis was that root restriction imposed by the container might hinder or rule out genetic differences in biomass allocation. We grew seedlings of two contrasted provenances of Canary Islands pine in mini-rhizotrons, 60 and 90 cm deep, and alternatively in standard bottom-open 200 cc forest containers. In the mini-rhizotrons, plants from the drier provenance allocated more biomass to roots, especially to the tap root and invested less in needles, both in a biomass and leaf area basis, and this morphological divergence increased between two harvests, undertaken at 57 and 115 days after planting. By contrast, confirming our hypothesis, at the 115 days harvest, the plants grown in standard containers did not exhibited significant differences between provenances for Leaf Mass Fraction, Root Mass Fraction and Leaf Area Ratio. We conclude that the physical constraint for root development imposed by small containers increases the probability of dismissing the genetic effect in biomass allocation when assessing forest reproductive materials at the short term, even when the whole plant growth (total dry weight) might be unaffected.
Inbreeding Depression in the Full-sib Offspring of Populus nigra L.
Authors: Benetka V. , Pospíšková M. , Vrátný F. , Tkaczyková M. 
Published: October 2017

Abstract
Controlled pollination was carried out in the species Populus nigra L. in a greenhouse on isolated branches between sisters and a brother - inbreeding (S x B). Female trees (sisters) were also exposed to open pollination (OP) in the neighbourhood of a male tree (brother) and other Populus nigra trees in the vicinity. The analysis of 11 microsatellites was done in the offspring from the inbreeding (S x B) and from the OP. In OP offspring was found 20-76% of viable individuals that were coming from pollination with brother’s pollen (spontaneous inbreeding). These individuals were separated from the offspring. In a randomised field trial the offspring were evaluated for two years. Fitness decreased in S x B offspring, traits of plant height, trunk diameter, height increment and resistance to Melampsora larici-populina Kleb. were lower in comparison with those of OP offspring. A coefficient of inbreeding depression (δ) ranged from 0.373 to 0.034. The significance of differences between the offspring from S x B and OP of the particular sisters was proved. About 30% of homozygous microsatellite loci were identified in inbred S x B offspring, which was more than in OP offspring. This difference was significant in the offspring of three sisters; it was not significant in the offspring of one sister. This trend corresponded to the results of growth traits.
The Chloroplast DNA Polymorphisms of White Oaks of Section Quercus in The Central Balkans
Authors: Slade D. , Škvorc Ž. , Ballian D. , Gračan J. , Papes D. 
Published: October 2017

Abstract
A total of 444 oak trees from 110 populations from a previously under-sampled area in the central Balkans were analysed using four primer/enzyme combinations which amplified and restricted four, largely non-coding regions of the maternally inherited chloroplast DNA. Using the nomenclature of PETIT et al. (2002 a) to classify the haplotypes and lineages, the seven haplotypes that were found in Croatia, Bosnia and Herzegovina, Montenegro, Albania, Macedonia and southern Kosovo consisted of haplotypes 2, 4, 5, 6, 7, 17, 31, as well as the subtypes of haplotypes 4 (a), 5 (a, b, c), and 17 (a). Five of these haplotypes belong to lineage A. One of these, haplotype 5, is present throughout the sampled area. The distributions of the other haplotypes from this lineage are more geographically structured. The other two haplotypes, haplotype 2 and haplotype 17, belong to lineages C and E, respectively. The data are combined with previous data by PETIT et al. (2002 b) to provide more detailed information of the postglacial routes of colonisation taken by oaks in south-eastern Europe.
Paxillus involutus Forms an Ectomycorrhizal Symbiosis and Enhances Survival of PtCOMT-modified Betula pendula in vitro
Authors: Tiimonen H. , Aronen T. , Laakso T. , Saranpää P. , Chiang V. , Häggman H. , Niemi K. 
Published: October 2017

AbstractThe ability of the PtCOMT (caffeate/5-hydroxyferulate O-methyltransferase from Populus tremuloides L.) - modified Betula pendula Roth. lines to form symbiosis with an ectomycorrhizal (ECM) fungus Paxillus involutus Batsch Fr. was studied in vitro. Lignin precursor gene PtCOMT was introduced into two B. pendula clones under the control of the cauliflower mosaic virus 35S promoter or the promoter of the sunflower polyubiquitin gene UbB1. Of the four transgenic lines, one 35SPtCOMT line (23) had a decreased syringyl/guaiacyl (S/G) ratio of root lignin, and two UbB1-PtCOMT lines (110 and 130) retarded root growth compared to the control clone. Both control clones and all transgenic lines were able to form ECMs with P. involutus, but the transgenic lines differed from the controls in the characteristics of the ECMs. The number of lateral roots covered with fungal hyphae and/or development of a Hartig net (HN) were reduced in line 23 with a decreased S/G ratio, and in lines 110 and 130 with slower root formation and changed root morphology, respectively. However, line 23 benefited more from the inoculation in lateral root formation than the control, and in lines 110 and 130 the percentage of viable plants increased most due to inoculation. The results show that B. pendula plants genetically transformed with the lignin gene PtCOMT could form mycorrhizal symbiosis regardless of changes in either the root S/G ratio or development. The benefits of the symbiosis were variable even in the closed in vitro system, and dependent on the clone or transgenic line and the ECM fungal symbiont.
Genetic Diversity of the Relict Plant Taiwania cryptomerioides Hayata (Cupressaceae) in Mainland China
Authors: Li Zhong-Chao , Wang Xiao-Lan , Ge Xue-Jun 
Published: October 2017

AbstractThe genetic diversity and differentiation of five populations of Taiwania cryptomerioides Hayata in mainland China were investigated using inter-simple sequence repeats (ISSR). In comparison with other coniferous species, T. cryptomerioides from mainland China possesses little genetic variation, particularly at the level of individual populations (the percentage of polymorphic loci, Nei’s gene diversity and Shannon’s indices of diversity at the species and population levels are 38.02%, 0.1326, 0.1986 and 9.27%, 0.035, 0.0518 respectively). In contrast, the level of population differentiation is much higher (GST: 0.7269; Shannon’s genetic differentiation: 0.7392; Hickory è B: 0.668; AMOVA genetic differentiation: 72.37%). The genetic divergence of pairs of populations was not significantly correlated with the geographical distance separating them. Current patterns of genetic variation were related to biogeographic history and the small population size. On the basis of these findings, we discuss the development of conservation strategies for this endangered species.