A multilocus phylogeny of theMetarhizium anisopliaelineage

Abstract

Metarhizium anisopliae, the type species of the anamorph entomopathogenic genus Metarhizium, is currently composed of four varieties, including the type variety, and had been demonstrated to be closely related to M. taii, M. pingshaense and M. guizhouense. In this study we evaluate phylogenetic relationships within the M. anisopliae complex, identify monophyletic lineages and clarify the species taxonomy. To this end we have employed a multigene phylogenetic approach using near-complete sequences from nuclear encoded EF-1alpha, RPB1, RPB2 and beta-tubulin gene regions and evaluated the morphology of these taxa, including ex-type isolates whenever possible. The phylogenetic and in some cases morphological evidence supports the monophyly of nine terminal taxa in the M. anisopliae complex that we recognize as species. We propose to recognize at species rank M. anisopliae, M. guizhouense, M. pingshaense, M. acridum stat. nov., M. lepidiotae stat. nov. and M. majus stat. nov. In addition we describe the new species M. globosum and M. robertsii, resurrect the name M. brunneum and show that M. taii is a later synonym of M. guizhouense.

Species associations and distributions of soil entomopathogenic fungi Metarhizium spp. in Japan

“…In eastern Canada, Mb was associated with the rhizosphere soil of trees rather than with the rhizospheres of plants in open fields (Wyrebek et al 2011), indicating the association of Mb with forested habitat. Furthermore, the cold-active and forest-dominant genotypic group of M. anisopliae sensu lato had been reported in the same area (Bidochka et al 2001), which partially corresponds to Mb (Bischoff et al 2009). Accordingly, Mb in Canada and Japan seem to have similar habitat and temperature preferences.…”

“…M. anisopliae s. l. is known to be a complex of cryptic species which are now classified by a molecular phylogenetic approach and can be distinguished by DNA sequences (Bischoff et al 2009). Bidochka et al (2001) demonstrated that cryptic species of M. anisopliae s. l. were associated with specific habitat type preferences rather than host insects.…”

“…The two groups also showed opposite physiological growth characteristics, which appeared to be an adaptation to the temperatures and UV radiations of their habitats. One isolates each from OG1 and OG2 were later identified as a different species, M. robertsii ( Mr ) and M. brunneum ( Mb ), respectively, by the recent taxonomy of Metarhizium (Bischoff et al 2009). Furthermore, Mr and Mb in the same area were preferentially detected from the rhizospheres of wildflowers and trees, respectively (Wyrebek et al 2011).…”

Back to the future: cordycipitoid fungi in a postgenomic world

“…ITS (Internal Transcribed Spacer) sequences have been widely accepted and promoted as a supposedly universal DNA “barcode” and, indeed, have adequately differentiated a huge variety of fungi. Nonetheless, it must be noted that for the Hypocreales – and especially for cordycipitoid entomopathogenic taxa – ITS has proven to have little to no taxonomic value (Driver et al 2000; Bischoff et al 2009). ITS sequences were excluded altogether from the analyses providing the new phylogenetic reclassifications of the genera Beauveria and Metarhizium as well as of the families Clavicipitaceae and Ophiocordycipitaceae (Rehner et al 2011; Kepler et al 2014; Quandt et al 2014).…”

“…Neither, of course, had the phylogenetically based reclassifications of species in these two genera (Bischoff et al 2009; Rehner et al 2011; Kepler et al 2014) yet happened, with their corresponding fragmentations of the well-recognised but morphologically defined species into multiple phylogenetically defined ones … and automatically placing some quotation marks around the base taxa in what we now know retrospectively to be major species complexes. During that symposium, I expressed hope that the next entomopathogenic fungus to be sequenced after these two critically important taxa would be Cordyceps militaris .…”