Molecular phylogeny ofAcremoniumand its taxonomic implications

Abstract

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Molecular systematics of the Phyllachorales (ascomycota, fungi) based on 18S ribosomal DNA sequences

“…Therefore, classifications which emphasize only a few taxonomic characters can artificially group polyphyletic taxa that morphologically resemble each other (Hausner et al, 1993;Spatafora and Blackwell, 1994). It is possible that the order Hypocreales is broader than currently delimited (Glenn et al, 1996), and the relatively long branch presented by 6 DFURFRPLDH may be a consequence of missing intermediate taxa which could be undiscovered, extinct, or unsampled (Alexopoulos et al, 1996). Alternatively, the grouping of 6SKDHURGRWKLV within the Hypocreales could also result from a faster rate of sequence change on 6SKDHURGRWKLV Only when additional sequences from other species of 6SKDHURGRWKLV or other stromatic genera (especially from the tropics) are available, the phylogenetic position and the taxonomic importance of apical and lateral paraphyses, currently used to delimit the Hypocreales, can be more rigorously evaluated.…”

The persistence of vertically transmitted fungi in grass metapopulations

“…Asexual Neotyphodium endophytes are automatically assumed to be 'trapped' in the host plant (see, for example, Clay & Holah 1999), although very little is known about the prevalence of their horizontal transmission (by either asexual or sexual spores) in nature. However, contagious spread should not be ruled out even in Neotyphodium endophytes because they produce asexual conidia on growth media (Glenn et al 1996) and on living plants (White et al 1996).…”

Towards a phylogenetic classification of Cordyceps: ITS nrDNA sequence data confirm divergent lineages and paraphyly

“…Hypocrea lutea and H. pilulifera were chosen as outgroup taxa in the analyses, based on published reports on the close relationship of Hypocrea (Hypocreaceae) and Cordyceps/Clavicipitaceae (Spatafora & Blackwell 1993, Glenn et al 1996.…”