Detection and Isolation of Epichloë Species, Fungal Endophytes of Grasses

Abstract

Epichloë species (including former Neotyphodium species) are endophytic fungi that significantly affect fitness of cool-season grass hosts, potentially by increasing nutrient uptake and resistance to drought, parasitism and herbivory. Epichloë species are obligately biotrophic, living in the intercellular spaces of their plant hosts, and spreading systemically throughout host aerial tissues. The reproduction of Epichloë species is versatile; some strains have both sexual and asexual modes of reproduction, but others are restricted to one or the other mode. The reproduction mode determines the dissemination mechanism, and the asexual species most important to agriculture are strictly seed-borne, cause no signs or symptoms, and are undetectable except by specialized microscopic, molecular or antigenic procedures. These procedures can be used to identify endophytes in a variety of plant tissues. Similar protocols can be modified to detect less common symbionts, such as the penicillate "p-endophytes," when they occur by themselves or together with Epichloë species.

Keywords: aniline-blue; detection; isolation; multiplex PCR; serology; symbiosis; tissue staining.