Biological and physiological characteristics of Epichloë bromicola endophyte symbiotic with Hordeum brevisubulatum

Biological and physiological characteristics of endophyte Epichloë bromicola strain WBE1 isolated from wild barley seeds were measured in a range of temperatures, pH, light, carbon source, nitrogen source and growth rate values. WBE1 was able to grow at temperate from 10 ℃ to 30 ℃ with the optimal temperature of 22~25 ℃ and stop growing at 4 ℃ and 35 ℃. The optimal pH for mycelial growth ranged 5.09 to 6.1. The ability of carbon source utilization decreased in the following order: maltose > D-sorbose > mannose > sucrose > lactose > starch > glucose. However, D-xylose inhibited the mycelial growth. The ability of nitrogen source utilization decreased in the following order: casein tryptone > beef extract > peptone > yeast > L-methionine > L-phenylalanine > leucine. However, potassium nitrate, praline and ammonium oxalate cannot be utilized by WBE1 and ammonium molybdate inhibited mycelial growth. Potato dextrose agar (PDA), oat meal agar (OMA), corn meal agar (CMA) and potato sugar agar (PSA) were optimal medium for WBE1. The mycelial growth rate on PDA reached maximum at the sixth week, then decreased gradually afterwards.