Effects of choke disease in the grass Brachypodium phoenicoides

Epichloë species (Clavicipitaceae, Ascomycota) are the causal agents of choke disease of grasses. This disease is characterized by the presence of cylindrical fungal stromata which wrap the immature inflorescences and inhibit the normal development of reproductive tillers. Using phenotypic and molecular characters, as well as mating compatibility tests, the fungus causing choke disease in Brachypodium phoenicoides (Poaceae) was identified as Epichloë typhina. A three year field experiment conducted with infected and uninfected plants of a single clone of B. phoenicoides showed no significant differences in biomass production during their vegetative growth stage, but the content of Ca, Mg, and Mn was greater, and that of Na was lower in infected plants compared to uninfected plants. Infected plants produced up to twice as many reproductive tillers than healthy plants, but their reproductive tissue biomass was smaller than that of healthy plants, because tiller development was arrested by choke forming stromata.