Effect of thiophanate methyl on the growth and physiological and biochemical characteristics of Hordeum brevisubulatum-Epichloë bromicola symbionts

Hordeum brevisubulatum, a salt-tolerant forage grass species in northern China, was studied to explore the impact of thiophanate methyl on the growth and physiological and biochemical characteristics of endophytic fungi within the wild barley. Results showed that the rate of emergence decreased significantly, from 85% to 72%, after sown seeds were treated with a 500× dilution of thiophanate methyl for 8 h (P<0.05), and the seedling carrier rate decreased significantly from 100% to 12% (P<0.05). Fungicide treatment reduced plant height and tillers of wild barley, whereas chlorophyll, malondialdehyde, and proline content and catalase, peroxidase, and superoxide enzyme activity were not significantly affected (P>0.05), C, N, and P content of wild barley decreased by 4.87%, 10.99%, and 13.50%, respectively, after fungicide treatment, compared with that in the control group (P<0.05). Therefore, treatment of seeds with 500× diluted thiophanate methyl for 8 h was an effective method to eliminate fungal endophytes in H. brevisubulatum.