Taxonomy of Neotyphodium endophytes of Chinese native Roegneria plants.

In this study we describe a new Neotyphodium species, Neotyphodium sinicum, found in natural symbiosis with asymptomatic Roegneria spp. (Elymus spp.) native to China. We investigated the host specificity, morphology, mating compatibility and molecular phylogenetic evidence for recognition of this new species. N. sinicum is host specific and seedborne and widely distributed in China. Most morphological characteristics of this new species are typical of other Neotyphodium species, but the growth on PDA plates tends to be more rapid. Three of five N. sinicum strains examined had double alleles of tefA and two of the five strains had double alleles of both tubB and tefA. Phylogenetic relationships based on sequences of tubB introns and tefA introns revealed that the allele-1 of tefA and tubB clustered together in a distinct subclade in the Epichloe bromicola/E. yangzii clade. The allele-2 grouped in the Epichlok" typhina clade (ETC). N. sinicum therefore appears to be an interspecific hybrid related to both E. yangzii and members of ETC. In mating tests N. sinicum failed to hybridize with E. yangzii.