Effects of 3-methylthiopropionic acid (MTPA) phytotoxin produced by Rhizoctonia solani on reactive oxygen species (ROS) metabolism of potato plants

摘要

Studies were conducted to investigate the effects of 3-methylthiopropionic acid (MTPA) produced by Rhizoctonia solani on antioxidant enzyme activities of potato in causing stem canker. The experiments were laid out in a completely randomized design with six treatments replicated five times. The treatments were 1, 2, 4, and 8 mM concentrations of MTPA while sterilized soil only (CK1) and sterilized soil with R. solani inoculum (CK2) served as control treatments. Results showed that compared with control plants (CK1), the activities of enzyme antioxidants such as superoxide dismutase (SOD), peroxidases (POD), and catalase (CAT) in potato stems treated with 8 mM MTPA increase by 86.95, 203.64, and 123.28%, respectively. Similarly, the activity of chitinase in the roots, stems and that of leaves increases by 120.22, 145.45, and 143.91%, respectively compared to CK1. However, the levels of malondiadehyde (MDA) in the roots, stems and leaves of 8 mM MTPA-treated plants decreased by 167.80, 156.52, 158.30%, respectively, compared to CK1. The study revealed that MTPA increased the activities of the anti-disease effective antioxidant enzymes of the potato plant due to the higher levels of ROS.