bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preliminary classification and ecology of dry grassland communities on Ölands Stora Alvar (Sweden)
Authors: Krahulec Frantiŝek , Rosén Ejvind , van der Maarel Eddy 
Published: March 2008

Four plant community types are described for Öland's Stora Alvar, the limestone plateau of South Öland and preliminary classified syntaxonomically:(1) Crepis pumila – Allium alvarense ass. (2) Helianthemum oelandicum – Galium oelandicum ass. (3) Gypsophila fastigiata – Globularia vulgaris ass. and (4) Veronica spicata – Avenula pratensis ass. (with two subassociations, the Sedum reflexum and Galium boreale subass.). The ecology of these types is discussed with emphasis on soil depth, frost perturbation and the combined effects of summer drought and grazing intensity.Various endemic taxa appear to be good character species for the community types described. The typical local ecology of some common species is discussed with the suggestion that they might have formed endemic ecotypes which should be further investigated.The communities described are very rich in cryptogams. The floristic variation as expressed by the cryptogamic species composition shows largely the same pattern as that shown by the phanerogams.
The utilization of organic nitrogen compounds as sole nitrogen source by some freshwater phytoplankters
Authors: Vieira A. A. H. , Klaveness D. 
Published: March 2008

Seven organic compounds containing nitrogen were tested as potential sources of nitrogen for five different species of freshwater algae. The chlorococcal green algae Selenastrum and Ankistrodesmus were the most versatile with regard to nitrogen sources; the diatom Cyclotella also grew well upon some organic nitrogen compounds. The desmid Arthrodesmus grew fast only on urea, while Cryptomonas did not grow well upon any of the organic compounds tested.More information is needed before the potential importance of organic nitrogen sources for freshwater phytoplankton can be assessed.
Fine structure of Pyramimonas octopus sp. nov., an octoflagellated benthic species of Pyramimonas (Prasinophyceae), with some observations on its ecology
Authors: Moestrup Øjvind , Hori Terumitsu , Kristiansen Aase 
Published: March 2008

A new octoflagellated species of Pyramimonas is described from three localities in Denmark. It is characterized by its ecology, being a marine psammophilic species associated with sand grains, and by details of the scaly covering on the cell surface. In the scale cover there are similarities to P. amylifera and to P. tetrarhynchus. P. octopus is distinguished by the possession of circular body scales of a type not previously found in the genus.The general fine structure of the new species is described with emphasis on scale structure, the internal structure of the cell body and the flagella.
A classification of the Monimiaceae ‐ an additional note
Authors: Philipson William R. 
Published: March 2008

Philipson, W. R. 1988. A classification of the Monimiaceae ‐ an additional note. ‐Nord. J. Bot. 8: 24. Copenhagen. ISSN 0107–055X.The names of one subfamily and three tribes are validated.
A revision of the tribe Forsskaoleae (Urticaceae)
Authors: Friis I. , Wilmot‐Dear C. M. 
Published: March 2008

Friis, I. & Wilmot‐Dear, C.M. 1988. A revision of the tribeForsskaoleae(Urticaceae). ‐ Nord. J. Bot. 8: 25–59. Copenhagen. ISSN 0107–055X.The tribe Forsskaoleae has been revised and the inflorescence and floral structure reinvestigated. The alternative interpretation of the flowers and inflorescences of Forsskaoleae proposed by Rivieres is rejected. A division of the tribe into two subtribes is tentatively maintained. The study of all genera is based on the total available material, with exception ofForsskaolea, of which only the types and some additional material have been studied, and an annotated survey of the six recognized species is presented. InDroguetiaseven species are recognized, distributed from tropical and South Africa to Madagascar, the Mascarenes, Java, and India. An infrageneric division of the genus is not tenable. The genusDidymodoxa, for the last hundred years united withAustralina, is reestablished with two species, both restricted to eastern and southern Africa. The genusAustralinais, within the new delimitation, disjunct between Australia, Tasmania and New Zealand on the one hand and Ethiopia and Kenya on the other. In view of the considerable differences between them, each of the two species is placed in a separate section, sect.Australinaand sect.Sarmentago. The lectotypification ofUrtica capensismade by Prain is shown to be in conflict with the protologue; a new lectotype is selected, with consequence for the nomenclature of a South African Acalypha species (Euphorbiaceae). All taxa are keyed out and described; distribution maps and illustrations are provided for most taxa.
The identification of some Mallomonas species of the M. doignonii group (Chrysophyceae)
Authors: Nicholls K. H. 
Published: March 2008

Nicholls, K. H. 1988. The identification of some Mallomonas species of the M. doignonii group (Chrysophyceae). ‐ Nord. J. Bot. 8: 109–116. Copenhagen. ISSN 0107–055X.The recent published literature on species of the Mallomonas doignonii group (Chrysophyceae) includes several errors in identification. Part of the reason for this probably relates to the apparent scarcity of M. doignonii itself (imperfectly known specimens from England, France and possibly, Texas). Mallomonas doignonii has been rediscovered in Ontario, Canada and an emended description is given. Features useful for identification of other similar species are also given and two new taxa (M. doignonii var. robusticostis and M. torquata var. torquata f.simplex) are described.
Ultrastructure and histochemistry of secretory ducts in Artemisia campestris ssp. maritima (Compositae)
Authors: Ascensäo Lia , Pais M. Salomé 
Published: March 2008

The histochemical characterization of the oleoresin produced by secretory ducts of Artemkiu campestris ssp. maritima revealed the presence of terpenoids (essential oils, resiniferous acids and probably steroids), alkaloids and fatty acids, eventually polyacetylenes.The ultrastructural study of A. campestris ducts enabled us to consider that the secretory activity begins very early during the duct development. The oleoresin deposited in the duct cavity is produced by epithelial and sub‐epithelial cells that contain, at the secretory phase, a great amount of smooth endoplasmic reticulum (SER) surrounding plastids with few thylakoids. These organelles may play an important role in the oleoresin production, the SER probably being responsible for some steps in the biosynthesis of oleoresin components and for the transport of the secreted material towards the plasmalemma. Endoplasmic reticulum and mitochondria probably have a role in the synthesis of steroids.After secretion, the duct glandular cells degenerate progressively. The extrusion process of secretion may be considered mero‐holocrine.
Growth and development of Potamogeton distinctus in an irrigation pond in SW Japan
Authors: Wiegleb Gerhard , Kadono Yasuro 
Published: March 2008

Growth and development of a population of Potamogeton distinctus were studied over one vegetation period.The morphological structure of the species is described. Maximum development of the size of shoot complexes occurred in August (up to 12 g dry weight/shoot complex). The plant exhibits a regular growth cycle with continuous horizontal and vertical growth that is illustrated by the development of horizontal shoots, vertical shoots and different plant parts. The lower horizontal shoots allow an extension up to 1.8 m from the point of germination. Before the rainy season in June the 1st to 5th generations of vertical shoots mainly contribute to the standing crop of the plants' stand, and after the rainy season the 5th to 9th generation shoots are predominant. Floating leaves make up the main proportion of biomass during the whole growth cycle. Almost 100% of the shoot complexes were found flowering and producing numerous seeds. Up to 16% of the standing crop are allocated to inflorescence and seeds in August. Turions failed to form that year because of rapid desiccation of the habitat. The observed average lifetime of a vertical shoot is appr. 65 days, the estimated turnover rate is between 2.15 and 2.27.
Embryology of barley: Time course and analysis of controlled fertilization and early embryo formation based on serial sections
Authors: Engell Kirsten 
Published: March 2008

The aim of this work was to determine the sequences and their time schedule in fertilization, embryo and endosperm development in a barley strain grown under controlled conditions. This study involved controlled pollinations and serial sectioning of material embedded in glycol methacrylate.In Hordeum vulgare cv. Bomi the pollen tube reaches the nucellus in the course of 40 minutes after pollination (m.a.P). In the next minutes the tube advances between the nucellar cells, through the filiform apparatus of the degenerating synergid and releases its contents, which is characterized by rod‐shaped starch grains. One of the sperm nuclei is fused with the egg nucleus 45 m.a.P., the second is in contact with the two polar nuclei 50–60 m.a.P., but the real connection between one of the polar nuclei and the sperm nucleus does not occur before 10 hours after pollination (h.a.P.). Triple fusion between all three nuclei takes place about 13 h.a.P. The first division in the zygote takes place 22–24 h.a.P. The embryo has got 3 cells at 34 h.a.P., 4 cells at 38 h. and 52 h.a.P. the embryo is composed of 7 cells. Protoderm formation takes place from a 14‐celled embryo stage at 72–80 h.a.P The primary endosperm nucleus divides 14 h.a.P. The next division takes place soon after the first; therefore the endosperm is 4‐nucleated already 18. h.a.P. Further divisions are synchronized, and 30–38 h.a.P. there will be more than 32 nuclei. The synchronous divisions continue, and the cellularisation begins at about 70 h.a.P. There is a tight correlation between the enlargement of the ovule and the embryo sac in the first days of the embryo development.
Late Weichselian flora and vegetation of Andøya, Northern Norway‐macrofossil (seed and fruit) evidence from Nedre Æråsvatn
Authors: Alm Torbjørn , Birks Hilary H. 
Published: March 2008

A Late Weichselian sediment column from Nedre Æråsvatn, Andøya, Northern Norway, spanning c. 20000 to 11000 B.P., has been analysed with respect to phanerogam macrofossils. Seeds are rare in the lower, marine part of the sequence (19500 to 15500 B.P.). They occur more frequently in the post‐15500 B.P. lacustrine sediments. Maximum seed numbers are associated with the 16000 to 15000 B.P. and 12800 B.P. (Bølling) ameliorations. Puccinellia and Papaver radicatum s.1. are the two main seed types. Their distribution and numbers agree with the Poaceae and Papaver pollen curves.Two main vegetation types are suggested to be dominant during most of the Late Weichselian: Plains and depressions with prominent Puccinellia, and polar deserts with Papaver, both in a dry environment. Both vegetation types decreased in the more humid climate of the Older Dryas and Allerød chronozones (12000 to 11000 B.P).Some hardy plant species, e.g. Papaver radicatum s.1., may have survived the entire Weichselian glaciation on Andøya. For most other phanerogams, a history of immigration and subsequent in situ survival, migration or disappearance is suggested.
Nomenclatural notes on Persicaria
Authors: Ekman Stefan , Knutsson Tommy 
Published: March 2008

The following names are lectotypified: Polygonum amphibium, P. foliosum, P. hydropiper, P. lapathifolium ssp. leptocladum, P. pallidum and P. persicaria, Polygonum persicaria var. incana is neotypified. Polygonum ruderale is a superfluous nomenclatural synonym of P. persicaria. The following new combinations are made: Persicaria lapathifolia ssp. pallida, P. lapathifolia var. incana and P. lapathifolia var. linicola. The nomenclature of H. B. Danser's early works is discussed.Flora Nordica Notes no. 8.
A new subspecies of Linum gyaricum (Linaceae) from Greece
Authors: Christodoulakis D. 
Published: March 2008

Christodoulakis, D. 1995. A new subspecies of Linum gyaricum (Linaceae) from Greece. ‐ Nord. J. Bot. 15: 145–147. Copenhagen. ISSN 0107–055X.A new subspecies, Linum gyaricum ssp. icaricum from Ikaria island (E Aegean, Greece), is described and illustrated.
A new species of Globba (Zingiberaceae) from Peninsular Malaysia
Authors: Ibrahim Halijah , Larsen Kai 
Published: March 2008

Ibrahim, H. & Larsen, K. 1995. A new species of Globba (Zingiberaceae) from Peninsular Malaysia. ‐ Nod. J. Bot. 15: 157–159. Copenhagen. ISSN 0107–055X. Globba nawawii from the east coast of Peninsular Malaysia is described, illustrated and compared with its nearest allies, G. corneri and G. unifolia.
Two new species of the genus Pelexia (Orchidaceae, Spiranthinae) from South America
Authors: Szlachetko Dariusz L. 
Published: March 2008

Szlachetko, D. L. 1995. Two new species of the genus Pelexia (Orchidaceae, Spiranthinae) from South America. ‐ Nord. J. Bot. 15: 173–175. Copenhagen. ISSN 0107–055X. Pelexia sheviakii and Pelexia collocaliae are described as new species from Ecuador and Paraguay respectively. Pelexia sheviakii differs from Pelexia bonariensis and any other species related by its lip form, which is rhomboid, has no constriction, and with basal lip thickenings produced on upper surface of claw. The most characteristic features of Pelexia collocaliae are U‐shaped callus at apices of petals, erect flowers, straight lateral sepals and narrow lip with two small calli near isthmus.
Euphorbia applanata sp. nov. (Euphorbiaceae) from Yemen, with a note on E. quaitensis
Authors: Thulin Mats , Al‐Gifri Abdul Nasser 
Published: March 2008

Thulin, M. & Al‐Gifri, A. N. 1995. Euphorbia applanata sp. nov. (Euphorbiaceae) from Yemen, with a note on E. quaitensis. ‐ Nord. J. Bot. 15: 193–195. Copenhagen. ISSN 0107–055X.The new species Euphorbia applanata, from limestone rocks in the Hadramaut Region in southern Yemen, is described and illustrated. The closely related E. quaitensis is recorded from a new locality in Hadramaut, and descriptions of its capsules and seeds are provided.
Tremelloid haustorial cells with haustorial filaments and potential host range of Tremella mesenterica
Authors: Zugmaier Walter , Oberwinkler Franz 
Published: March 2008

Zugmaier, W. & Oberwinkler, F. 1995. Tremelloid haustorial cells with haustorial and potential host ranges of Tremella mesenterica. ‐ Nord. J. Bot. 15: 207–213. Copenhagen. ISSN 0107–055X.In vitro and in vivo haustorial cells of Tremella mesenterica, consisting of a subglobose basal part with one or more thread‐like haustorial filaments, were examined using light and electron microscopy. The haustorial cells developed from clamp connections of hyphal septa or intercalarily. Mostly such haustorial cells were monokaryotic, but in a few cases also dikaryotic haustorial cells were observed. In vitro, the host range of Tremella mesenterica was tested with the corticiaceous homobasidiomycetes Peniophora erikssonii, P. quercina and Phanerochaete eremea. The in vitro interaction of Tremella mesenterica with all these fungi was principally the same as in vivo with Peniophora laeta. A single micropore connected the cytoplasm of the haustorial filament with that of the respective host cell. The pore domain at the host side was delimited by curved ER cisternae only in Peniophora quercina, but not in Peniophora erikssonii and Phanerochaete cremea.
Rubus vestervicensis (Rosaceae) — its hybrid origin revealed by DNA fingerprinting
Authors: Kraft Thomas , Nybom Hilde , Werlemark Gun 
Published: March 2008

Kraft, T., Nybom, H. & Werlemark, G. 199.5. Rubus vestervicensis (Rosaceae) — its hybrid origin revealed by DNA fingerprinting. — Nord. 3. Bot. 1.5: 237–242. Copenhagen. ISSN 0107‐055X.The large number of species in Rubus subgenus Rubus are thought to have arisen, at least in part, through hybridiation between facultatively apomictic species. R. vestervicensis is known only from a small island off the Swedish east coast. It has been suggested that it is a hybrid between R. grabowskii and R. pedemontanus. We have compared these species with DNA fingerprinting and our results support the hybridization hypothesis. All bands found in the fingerprint of R. grabowskii and about half of the bands found in R. pedemontanus were present in R. vestervicensis, suggesting that the latter species was derived from fertilization of an unreduced R. grabowskii egg cell with R. pedemontanus pollen.
Exotesta morphology of the Gardenieae — Gardeniinae (Rubiaceae)
Authors: Persson Claes 
Published: March 2008

Persson, C. 1995. Exotesta morphology of the Gardenieae‐Gardeniinae (Rubiaceae). ‐Nord. J. Bot. 15: 285–300. CGpenhagen. ISSN 0107–055X.Exotesta morphology of 68 species in 59 genera of the Gardeniinae were examined with the aid of scanning and light microscopy. The shape of the exotesta cells in surface is either isodiametrical or elongate and both shapes occur among New World and Old World genera. All genera, except forMonosalpinx, PosoqueriaandMacrosphyra, are provided with secondary thickenings in the cell walls of the exotesta. The majority of the genera has a thickened radial wall. In the Asian generaCatunaregam, Deccania, Tamilnadiaand the mainly Pacific genera,AtractocarpusandTrukiathickenings of the radial wall are very low or absent. In nearly half the genera the inner tangential wall is provided with thickenings, usually in the shape of a continuous plate. However, in four African genera,Atractogyne, Didymosalpinx, MitriostigmaandSherbournia, the wall is provided with elongate anastomosing ribs.Atractocarpusdiffers markedly from the rest of the Gardeniinae by its ring‐like thickenings in the inner tangential wall. Thickenings, in the shape of a continuous plate, in the outer tangential wall is restricted to three neotropical genera,Alibertia, AmaiouaandBorojoa. Presence of distinct knobs is common in palaeotropical genera, whereas in neotropical genera this feature is only present inCasasiaandKotchubaea. It is concluded that data on exotesta morphology alone does not support any of the previously proposed informal groups, but may still be an important character to deduce phylogenetic relationships, primarily on a level just above the genus.
Iphigenia socotrana sp. nov. (Colchicaceae), with a note on I. oliveri
Authors: Thulin Mats 
Published: March 2008

Thulin, M. 1995. Iphigenia socotrana sp. nov. (Colchicaceae), with a note on I. oliveri. — Nord. J. Bot. 15: 403–405. Copenhagen. ISSN 0107–055X.The new species Iphigenia socotrana, from limestone rocks along the northern escarpment of Socotra, is described and illustrated. I. somaliensis is lectotypified and reduced to a synonym of I. oliveri.
Pholidota pygmaea (Orchidaceae) — A new species from Arunachal Pradesh, India
Authors: Chowdhery H. J. , Pal G. D. 
Published: March 2008

Chowdhery, H.J. & Pal, G.D. 1995. Pholidota pygmaea (Orchidaceae) — A new species from Arunachal Pradesh, India. — Nord. J. Bot. 15: 411–413. Copenhagen. ISSN 0107–055X.A new species of Pholidota, P. pygmaea from Arunachal Pradesh, India is described.
Stomatal myrosin cells in Caricaceae. Taxonomic implications for a glucosinolate‐containing family
Authors: Jørgensen Lise Bolt 
Published: March 2008

Jørgensen, L. B. 1995. Stomatal myrosin cells in Caricaceae. Taxonomic implications for a glucosinolate‐containing family. — Nord. J. Bot. 15: 523–540. Copenhagen. ISSN 0107–055X.Stomatal myrosin cells are shown to be present in Carica goudotiana, C. papaya, C. guercifolia and Jarilla caudata of the Caricaceae. They are found in the epidermis of all green parts, viz. leaves, stems, and immature fruits, and also of cotyledons from germinating seeds. They are structurally the same as the stomatal myrosin cells in other glucosinolate‐ and myrosinase‐containing families, Resedaceae, Tovariaceae and Bata‐ceae, and comparable to the idioblastic myrosin cells from e.g. Brassicaceae and Capparaceae. The stomatal myrosin cells have vacuoles filled with proteinaceous material and cytoplasm rich in rough endoplasmic reticulum. During embryogenesis single adaxial epidermal cells of the cotyledons can be distinguished as myrosin cells, since their protein bodies are homogeneous and without globoids and become filled with protein earlier than the protein bodies with globoids present in the other epidermal cells or the mesophyll cells of the cotyledons. This is analogous to myrosin cells in embryos from Brassicaceae. In germinating seeds the single epidermal myrosin cells divide to form precursors of guard cells, thus turning into stomatal myrosin cells in the green cotyledons. The presence of myrosin cells supports a taxonomic treatment of Caricaceae together with the majority of the other glucosinolate‐containing families in the major glucosinolate clade.
Morphometric analyses of capsule and seed traits in Scandinavian Papaver radicatum (Papaveraceae) in relation to the bicentric distribution pattern
Authors: Selin Eva 
Published: March 2008

The bicentric distribution pattern of certain plant species in the southern and northern Scandinavian mountains has been explained in different ways. Either by refugial survival, by late‐glacial immigration to the first deglaciated areas in southern and northern Norway or by a successive fragmentation of wide‐distributed populations during post‐glacial time — or by present‐day ecological factors. Even if the bicentric distribution pattern is at least partly explained by present‐day ecological conditions, the question about the origin of the bicentric distribution still remains. One way to tackle this problem, is to investigate the morphometric and/or the genetic differentiation between isolated populations of ‘bicentric’ species and its impact on the explanation of the disjunct pattern.The overall morphometric differentiation pattern in seeds and capsules was investigated in populations of Papaver radicatum, a perennial herb with a bicentric distribution in the Scandinavian mountain range. Canonical variates analysis of capsules separates the populations into two groups in accordance with their geographic origin, i.e. the regions of southern and northern Scandinavia. The differentiation pattern indicates a two‐step development of the present‐day distribution: first separation of the southern and northern Scandinavian occurences of older origin, then separation between populations within each region. The results from canonical variates analysis of seeds shows a weaker variation pattern with a tendency of overlapping inter‐region populations. The most northerly situated populations from the southern region are grouped with populations from the northern region.The pattern of differentiation in capsules may be interpretated in terms of refugial survival or late‐glacial immigration. However, the variation pattern in seeds rather points to a scenario where a widespread occurrence that previously ranged from southern to northern Scandinavia was successively fragmented, which makes a postglacial development of the differentiation pattern more probable.
Comparative leaf anatomical studies of Acinos species (Labiatae) from Wkey
Authors: Kaya Ayla , Koca Fehmýye 
Published: March 2008

A comparative study was undertaken on the leaves of six Acinos taxa in order to assess anatomical variations which may be a useful feature to identify each one and to evaluate their significance for the taxonomy of the genus. All species have glandular and non‐glandular trichomes, diacytic stomata, and dorsiventral leaves.The results of this survey show that trichomes not only are different in cell numbers within the species but also in density. When transverse sections are compared, some differences in their midrib shapes, the protruding midrib, the number of palisade and spongy layers and upper anticlinal epidermal wall may provide interesting starting points for the characterisation of the species.