271 research outputs found

    Collembola help lichens in competition with algae.

    Get PDF

    A preliminary phylogeographic study of Flavopunctelia and Punctelia inferred from rDNA ITS-sequences

    Get PDF
    A preliminary phylogeny of the genera Flavopunctelia and Punctelia is presented. Genus and species delimitations have been investigated using ITS rDNA-sequencing of populations from different continents. Current genus delimitations of Flavopunctelia, Punctelia and Parmelia are confirmed and the species status of recently resurrected Punctelia ulophylla is confirmed. The status of three cryptic species, Flavopunctelia soredica, Punctelia perreticulata and P. stictica is discussed. Flavopunctelia borrerioides and Punctelia perreticulata are reported from China for the first time.Esitatakse perekondade Flavopunctelia ja Punctelia esialgne fülogeneesi rekonstruktsioon. Perekondade ja liikide eraldamist on uuritud erinevatelt kontinentidelt pärinevate populatsioonide ITS rDNA sekventside alusel. Senine perekondade Flavopunctelia, Punctelia ja Parmelia piiritlemine on leidnud kinnitust, samuti liigi Punctelia ulophylla staatus. Arutletakse kolme krüptilise liigi, Flavopunctelia soredica, Punctelia perreticulata ja P. stictica staatuse üle. Teatatakse liikide Flavopunctelia borrerioides ja Punctelia perreticulata esmasleidudest HiinasFil: Thell, Arne. Lund University; SueciaFil: Herber, B.. Universitat Hamburg; AlemaniaFil: Aptroot, A.. Centraalbureau voor Schimmelcultures; Países BajosFil: Adler, Monica Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Feuerer, T.. Universitat Hamburg; AlemaniaFil: Kärnefelt, Ingvar. Lund University; Sueci

    An evaluation of the monophyly of Massarina based on ribosomal DNA sequences

    Get PDF
    The monophyletic status of the genus Massarina was evaluated on the basis of phylogenetic analysis of the partial small subunit gene (SSU), internal transcribed spacers (ITS 1 & 2), and 5.8S gene sequences of the ribosomal DNA. Species of Massarina used in the study clustered into two distinct clades with high bootstrap support in trees generated from maximum parsimony, weighted parsimony, maximum likelihood, and neighbor-joining analyses. The hypothesis that Massarina species belong to a phylogenetically monophyletic group is rejected. Species with narrowly fusiform ascospores form a monophyletic clade with Lophiostoma, a genus highly similar in morphology. The five species currently accepted in Massarina with such spore morphology are here transferred into the genus Lophiostoma. Massarina species with broadly fusiform to ellipsoidal ascospores are retained as Massarina s. str., lectotypified by M. eburnea. Massarina walkeri is presently excluded from both Massarina and Lophiostoma. The transfer of M. papulosa to a new genus Oletheriostrigula is verified.published_or_final_versio

    The family Pleosporaceae: intergeneric relationships and phylogenetic perspectives based on sequence analyses of partial 28S rDNA

    Get PDF
    The Pleosporaceae is an important loculoascomycete family. There has been disagreement, however, regarding the taxonomic placement of many genera within this family. This study investigates phylogenetic relationships among the genera Cochliobolus, Kirschsteiniothelia, Leptosphaerulina, Macroventuria, Pleospora, Pyrenophora, and Wettsteinina. Partial 28S rDNA sequences from taxa within these genera were analyzed with maximum parsimony, likelihood and Bayesian methods. Cochliobolus can be segregated broadly into two groups as previously proposed. Pleospora is polyphyletic in its current sense. Taxa with Stemphylium anamorphs are closely related to Cochliobolus and fit within the Pleosporaceae, whereas the affinities of Pleospora herbarum and P. ambigua are still ambiguous. Pyrenophora constitutes a monophyletic group within the Pleosporaceae, whereas Leptosphaerulina and Macroventuria appear to share phylogenetic affinities with the Leptosphaeriaceae and Phaeosphaeriaceae. Phylogenies indicate that Wettsteinina should be excluded from the Pleosporaceae. Similar findings are reported for Kirschsteiniothelia, which is probably polyphyletic. Anamorphic characters appear to be significant (especially in Cochliobolus) while ascospore morphologies, such as shape and color and substrate occurrence are poor indicators of phylogenetic relationships among these loculoascomycetes.published_or_final_versio

    Mycosphaerella punctiformis revisited: morphology, phylogeny, and epitypification of the type species of the genus Mycosphaerella (Dothideales, Ascomycota)

    Get PDF
    Mycosphaerella punctiformis, the type species of the genus Mycosphaerella, is epitypified by material collected on Quercus robur in The Netherlands. The teleomorph is described in planta, and the Ramularia anamorph, for which the new name R. endophylla is proposed, and the Asteromella spermatial state are characterized in vitro. Sequence data of the nuclear ribosomal DNA are presented and analyzed together with other Mycosphaerella spp. with Ramularia and several other anamorphs. Several strains originating from Quercus, Acer and Tilia showed diverging ITS sequences, indicating that the M. punctiformis complex may comprise more than a single phylogenetic species, but this could not be confirmed by the analysis of our dataset. An endophytic phase is established for the first time in the life-cycle of M. punctiformis, as the species was repeatedly isolated from surface sterilized green healthy leaves of Quercus robur in summer at the epitype localit

    Preadvies mossen en korstmossen.

    Get PDF
    Binnen het in OBN-kader uitgevoerd onderzoek was tot nu toe vaak aandacht voor de ruim 580 soorten mossen (inclusief variëteiten) en 800 soorten korstmossen die in Nederland voorkomen. Uit de Rode Lijsten blijkt dat er alle aanleiding is om meer aandacht te geven aan deze groepen. De achteruitgang van mossen en korstmossen speelt landelijk en in alle landschappen. Het Deskundigenteam Heuvellandschap heeft het preadvies begeleid namens alle deskundigenteams (droog zandlandschap, nat zandlandschap en beekdallandschap; rivierenlandschap; laagveenlandschap; zeekleilandschap; duin- en kustlandschap). Bij dit onderwerp zijn betrokken geweest: Universiteit Utrecht, Universiteit van Amsterdam, B ware (Radboud Universiteit), BLWG, Forestfun ecologisch advies en onderzoek, Alterr

    The role of cattle in maintaining plant species diversity in wet dune valleys

    Get PDF
    The succession of species-rich wetland vegetation in dune valleys into species-poor dwarf shrub vegetation was followed by means of permanent vegetation plots, in which the cover of vascular plant, moss and lichen species were recorded over a period of up to 33 years. Low density cattle grazing is an effective substitute for rabbits in stalling this succession, thus preserving the local plant species diversity. The influence of direct rabbit grazing pressure on the vegetation was studied in exclosures. The differences were significant, but not long-lasting after the exclosures had been opened again to the rabbits. Cladina lichen-rich Empetrum-heathland in the dunes is a stage in a probably cyclic succession that might be triggered by grazing. The total vascular plant, moss and lichen diversity of the dune ecosystem can be maintained by a combination of extensive cattle grazing and a regular but limited re-creation of pioneer situations
    corecore