Effects of Epichloe endophyte infection on growth, physiological properties and seed germination of wild barley under saline conditions

Wild barley (Hordeum brevisubulatum) is a grass that inhabits alkalized meadows in northern China. An asexual Epichloe bromicola endophyte was detected in seeds and leaf sheaths in all wild barley samples from Gansu Province, China. In this research, we determined the effects of the E. bromicola endophyte on growth, physiological properties and seed germination of wild barley under salt stress through a set of experiments. Our results demonstrate that endophyte-infected (E+) plants produced more tillers, higher biomass and yield, higher chlorophyll content and superoxide dismutase activity than endophyte-free (E-) plants under high salt stress. Seed germination parameters of E+ biotype were significantly higher than those of E- plants when NaCl concentration reached 200 and 300 mM. Our results demonstrate that E. bromicola endophytes increased tolerance to salt stress in wild barley by increasing seed germination and growth, and altering plant physiology.