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1. Plant species persistence in natural communities requires coping with biotic and abiotic challenges. These challenges also depend on plant community composition and diversity. Over time, biodiversity effects have been shown to be strengthened via increasing species complementarity in mixtures. Little is known, however, whether differences in community diversity and composition induce rapid transgenerational phenotypic adaptive differentiation during community assembly. We expect altered plant-plant and other biotic interactions (mutualists or antagonists) in high vs. low diverse communities to affect immediate within-and between-species trait differentiations due to competition for light and nutrients. 2. Three years after the initiation of a large-scale, long-term biodiversity experiment in Jena, Germany, we tested for effects of varying experimental plant community diversity (1-60 plant species; one to four plant functional groups) and composition (with or without legumes and/or grasses) on phenotypic differentiation and variation of the tall herb Knautia arvensis. We measured reproduction at different diversity levels in the Jena Experiment (residents hereafter) and, in an additional common garden experiment without competition, recorded subsequent offspring performance (i.e. growth, reproductive success and susceptibility to powdery mildew) to test for differentiation in phenotypic expression and variability. 3. We observed phenotypic differences among diversity levels with reduced fecundity of K. arvensis residents in more diverse communities. In the next generation grown under common garden conditions, offspring from high-diversity plots showed reduced growth (i.e. height) and lower reproduction (i.e. fewer infructescences), but increased phenotypic trait variability (e.g. in leaf width and powdery mildew presence) and also tended to be less susceptible to powdery mildew infection. 4. Community composition also affected Knautia parents and offspring. In the presence of legumes, resident plants produced more seeds (increased fecundity); however, germination rate of those seeds was reduced at an early seedling stage (reduced fertility). 5. Synthesis. We conclude that rapid transgenerational effects of community diversity and composition on both mean and variation of phenotypic traits among offspring exist. In addition to heritable variation, environmentally induced epigenetic and/or maternal processes matter for early plant community assembly and may also determine future species coexistence and community stability.
The oomycete Plasmopara obducens was first described on wild Impatiens noli-tangere in Germany in 1877. About 125 years later the first occurrence of P. obducens on cultivated I. walleriana in the United Kingdom was reported, and a worldwide epidemic followed. Although this pathogen is a major threat for ornamental busy lizzy, the identity of the pathogen remained unconfirmed and the high host specificity observed for the genus Plasmopara cast doubts regarding its determination as P. obducens. In this study, using multigene phylogenies and morphological investigation, it is revealed that P. obducens on I. noli-tangere is not the conspecific with the pathogen affecting I. walleriana and another ornamental balsam, I. balsamina. As a consequence, the new names P. destructor and P. velutina are introduced for the pathogens of I. walleriana and I. balsamina, respectively.
Ciboria ploettneriana, Schroeteria decaisneana, and S. poeltii produce morphologically very similar apothecia emerging from fallen stromatized seeds of Veronica spp., the former two on V. hederifolia agg. in temperate central Europe and S. poeltii on V. cymbalaria in mediterranean southern Europe. They are described and illustrated in detail based on fresh collections or moist chamber cultures of infected seeds. A key is provided to differentiate the three species from their teleomorphs. For the first time, connections between two teleomorphs and two Schroeteria anamorphs are reported. Members of the anamorph-typified genus Schroeteria are known as host-specific plant parasites that infect seeds of different Veronica spp. In earlier times, they were classified in the Ustilaginales (Basidiomycota), but since more than 30 years, they are referred to as false smut fungi producing smut-like chlamydospores, based on light microscopic and ultrastructural studies which referred them to the Sclerotiniaceae (Helotiales). During the present study, rDNA sequences were obtained for the first time from chlamydospores of Schroeteria bornmuelleri (on V. rubrifolia), S. decaisneana (on V. hederifolia), S. delastrina (generic type, on V. arvensis), and S. poeltii (on V. cymbalaria) and from apothecia of C. ploettneriana, S. decaisneana, and S. poeltii. As a result, the anamorph-teleomorph connection could be established for S. decaisneana and S. poeltii by a 100% ITS similarity, whereas C. ploettneriana could not be connected to a smut-like anamorph. Ciboria ploettneriana in the here-redefined sense clustered in our combined phylogenetic analyses of ITS and LSU in relationship of Sclerotinia s.l., Botrytis, and Myriosclerotinia rather than Ciboria, but its placement was not supported. Its affiliation in Ciboria was retained until a better solution is found. Also Schroeteria poeltii clustered unresolved in this relationship but with a much higher molecular distance. The remaining three Schroeteria spp. formed a strongly supported monophyletic group, here referred to as "Schroeteria core clade", which clustered with medium to high support as a sister clade of Monilinia jezoensis, a member of the Monilinia alpina group of section Disjunctoriae. We observed ITS distances of 5-6.3% among members of the Schroeteria core clade, but 13.8-14.7% between this clade and S. poeltii, which appears to be correlated with the deviating chlamydospore morphology of S. poeltii. Despite its apparent paraphyly, Schroeteria is accepted here in a wide sense as a genus distinct from Monilinia, particularly because of its very special anamorphs. A comparable heterogeneity in rDNA analyses was observed in Monilinia and other genera of Sclerotiniaceae. Such apparent heterogeneity should be met with skepticism, however, because the inclusion of protein-coding genes in phylogenetic analyses resulted in a monophyletic genus Monilinia. More sclerotiniaceous taxa should be analysed for protein-coding genes in the future, including Schroeteria. Four syntype specimens of Ciboria ploettneriana in B were reexamined in the present study, revealing a mixture of the two species growing on V. hederifolia agg. Based on its larger ascospores in comparison with S. decaisneana, a lectotype is proposed for C. ploettneriana.
Species of rust fungi of the genus Milesina (Pucciiastraceae, Pucciniales) are distributed mainly in northern temperate regions. They host-alternate between needles of fir (Abies spp.) and fronds of ferns (species of Polypodiales). Milesina species are distinguished based on host taxonomy and urediniospore morphology. In this study, 12 species of Milesina from Europe were revised. Specimens were examined by light and scanning electron microscopy for urediniospore morphology with a focus on visualising germ pores (number, size and position) and echinulation. In addition, barcode loci (ITS, nad6, 28S) were used for species delimitation and for molecular phylogenetic analyses. Barcodes of 72 Milesina specimens were provided, including 11 of the 12 species. Whereas urediniospore morphology features were sufficient to distinguish all 12 Milesina species except for 2 (M. blechni and M. kriegeriana), ITS sequences separated only 4 of 11 species. Sequencing with 28S and nad6 did not improve species resolution. Phylogenetic analysis, however, revealed four phylogenetic groups within Milesina that also correlate with specific urediniospore characters (germ pore number and position and echinulation). These groups are proposed as new sections within Milesina (sections Milesina, Vogesiacae M. Scholler & Bubner, sect. nov., Scolopendriorum M. Scholler & Bubner, sect. nov. and Carpaticae M. Scholler & Bubner, sect. nov.). In addition, Milesina woodwardiana Buchheit & M. Scholler, sp. nov. on Woodwardia radicans, a member of the type section Milesina, is newly described. An identification key for European Milesina species, based on urediniospore features, is provided.
The new species Erysiphe asclepiadis is described, illustrated and discussed. A new Chinese collection of Erysiphe robiniicola has recently been found that can be used to elucidate and discuss the confused taxonomy and nomenclature of this species and other taxa of Erysiphe s. lat. on Robinia spp. Based on a re-examination of type material in connection with the data given in the protologue, it can be shown that Capnodium lygodesmiae must be reduced to synonymy with Ampelomyces quisqualis. The confusion surrounding the name C. lygodesmiae, caused by the occurrence of the hyperparasite A. quisqualis on a powdery mildew fungus with abundant chasmothecia, is discussed in detail. The new combination, Golovinomyces caulicola (; Spolverinia caulicola), is proposed for the powdery mildew that serves as host of C. lygodesmiae.
There are 63 known species of Thecaphora (Glomosporiaceae, Ustilaginomycotina), a third of which occur on Asteraceae. These smut fungi produce yellowish-brown to reddish-brown masses of spore balls in specific, mostly regenerative, plant organs. A species of Thecaphora was collected in the flower heads of Anthemis chia (Anthemideae, Asteraceae) on Rhodes Island, Greece, in 2015 and 2017, which represents the first smut record of a smut fungus on a host plant species in this tribe. Based on its distinctive morphology, host species and genetic divergence, this species is described as Thecaphora anthemidis sp. nov. Molecular barcodes of the ITS region are provided for this and several other species of Thecaphora. A phylogenetic and morphological comparison to closely related species showed that Th. anthemidis differed from other species of Thecaphora. Thecaphora anthemidis produced loose spore balls in the flower heads and peduncles of Anthemis chia unlike other flower-infecting species.
Among plant remains from Mesolithic layers dating from 9249 to 7779 B.C. at the excavation site of Friesack IV in north-eastern Germany, nutlets of Urtica kioviensis were identified. Morphological studies have shown that they clearly differed from all other European Urtica species investigated. In contrast, pollen morphological investigations revealed only slight differences between the central European Urtica species, which could hardly have been noticed during routine or normal pollen analyses. The records of U. kioviensis nutlets are the first subfossil finds reported and prove the indigenous status of this taxon in north-eastern Germany. The records are discussed in the context of the overall species spectrum of the Mesolithic layers and consequences for the interpretation of pollen analytical studies concerning human impact are pointed out
Vom Seidenbau in Krausnick
(2004)
Von Anemone bis Zimbelkraut
(1999)