Multigene phylogeny of Epichloë species, fungal symbionts of grasses

摘要: Epichloe species are fungal symbionts (endophytes) of grasses, many of which are benign or mutualistic and have a balance of horizontal (contagious) and vertical (seed-borne) transmission, whereas others mainly transmit horizontally and are more antagonistic. Over the past eight years several Epichloe species have been described based largely on the biological species concept. We conducted a multi-gene phylogenetic analysis to evaluate these endophytes as phylogenetic species, and thereby assess the relationship of phylogenetic and biological species. Variation mainly in introns of genes encoding β-tubulin (tub2), translation elongation factor 1-α (tef1), and actin (act1) provided robust phylogenetic signal distinguishing the described Epichloe species. Outgroup rooting split the genus into two major groups. One group included most species with balanced transmission strategy, and in this group the …