Growth performance of different Epichloë sinensis strains on media with different additives

Abstract

Background: Epichloë sinensis is a newly found endophyte species that is frequently involved in symbiosis with Festuca sinensis. There are a little reports on the characteristics of E. sinensis in vitro. Methods: In the present study, five E. sinensis endophyte strains (strain ID 1, 2, 41D, 57D, 111D) isolated from different F. sinensis ecotypes were used to evaluate their antioxidant capacities and enzyme activities. Also, the growth of E. sinensis on potato dextrose agar (PDA) with different additives was investigated.Results: The five strains had significantly different (p < 0.05) total antioxidant capacities and radical-scavenging abilities. In most cases, the growth rate of strain 1 was the fastest (p < 0.05), and that of strain 57D was the slowest (p < 0.05). The growth rates of these five strains on PDA with vitamins significantly (p < 0.05) increased with increasing vitamin concentration. The growth rates of these five strains on PDA with plant growth regulators also significantly (p < 0.05) increased; however, the increase was inconsistent at different concentrations of indole-3-acetic acid and gibberellin. Low concentrations (5 and 10 mg L −1 ) of forchlorfenuron (KT-30) significantly promoted the growth of all five strains, whereas high concentrations (20 and 40 mg L −1 ) of KT-30 significantly inhibited their growth (p < 0.05). The Na + , Cd 2+ , Zn 2+ , and Cr 6+ ions all inhibited the growth of these five strains, and their growth rates were significantly decreased with an increase in ion concentrations (p < 0.05). Under Na + stress, strain 41D grew the fastest and had the strongest tolerance (p < 0.05); under Cd 2+ , Zn 2+ , and Cr 6+ stresses, strain 111D grew the fastest and had the strongest tolerance (p < 0.05). Conclusions: The results indicated that the E. sinensis had antioxidant activities and hydrolase activities. Additives could promote or inhibit the growth of the strains in different degrees. All these evaluations in the present study improve our understanding of the E. sinensis endophyte and provide referenced information for further studies.