Acibenzolar-S-methyl induced defense against black rot in cabbage

An investigation was conducted to determine the most effective dose and timing of application of Acibenzolar-S-methyl (ASM) to reduce the severity of black rot caused by Xanthomonas campestris pv. campestris (Xcc) and to induce defense-related enzymes such as catalase (CAT), peroxidase (POX), and superoxide dismutase (SOD) in cabbage plants (Brassica oleracea var. capitata L.) under pot conditions. In the susceptible cabbage variety Golden Acre, the minimum severity of black rot (31.68%) was observed when sprayed with a concentration of 400 µg/ml of ASM before Xcc inoculation. Moreover, when the same concentration of ASM was sprayed on Golden Acre cabbage plants at various intervals (0, 24, 48, 72, and 96 h) before Xcc inoculation, the least disease severity (11.72%) was recorded when treated with ASM 72 h prior to inoculation. In the resistant variety Pusa Mukta, treatment with ASM (400 µg/ml) and Xcc (108 cfu/ml) induced the expression of CAT (4.097 mM mg protein^-1 min^-1), POX (4.397 mM mg protein^-1 min^-1), and SOD (13.407 units mg protein^-1) activities, which peaked at 5 days after inoculation (DAI) and subsequently declined. The population of Xcc artificially inoculated in both Pusa Mukta and Golden Acre cabbage plants was lower in the ASM-treated groups compared to the control.