Abstract: The growth and physiological characteristics of Epichloё endophyte infected (E+) and endophyte free (E-) Melica transsilvanica were observed under different Pb concentrations (0, 200, 500, 1000, 1500, 2000 mg·L^-1) in a pot experiment. It was found that with increase in Pb concentration, plant height initially increased and then decreased. At the Pb concentration of 500 mg·L^-1, the proline content of E+ plants was 35.2% higher (P<0.05) than in the Controls. At Pb concentrations of 1500 mg·L^-1 and above, plant height was significantly inhibited. The root fresh weight exhibited the largest decrease, being 82.5% lower than the control (P<0.05); meanwhile, the MDA concentration in leaves increased significantly. When the Pb concentration was 2000 mg·L^-1, the MDA content of E+ plants were significantly higher than the Control (P<0.05), and the content of proline in the plant increased initially, and then decreased. Compared with M. transsilvanica plants without Epichloё endophytic fungi, the aboveground and underground biomass of E+ plants were both higher than in E- plants; the proline content of E+ plants was significantly higher than in the E- plants at the 1500 mg·L^-1 Pb concentration (P<0.05); and the MDA content of E+ plants was 25% lower than in E- plants (P<0.05), especially at the 2000 mg·L^-1 Pb concentration. In conclusion, the growth and physiological adaptability to Pb stress of M. transsilvanica infected with endophyte fungi was enhanced.

Key words: Melica transsilvanica, endophyte, Pb stress, physiological characteristics