Effect of intermittent exposures of SO2 on the leaf blight caused by Alternaria brassicicola on Indian mustard

▶ The mustard germplasm has been found susceptible to Alternaria brassicicola and SO2 at concentrations relevant to ambient environment. ▶ The mustard cv. Kalamoti demonstrated tolerance against the A. brassicicola and did not exhibit blight and significant reduction in plant growth and yield. ▶ Due to exposure to 143 μg SO2 m−3 the cv. Kalamoti became susceptible to the fungus. ▶ In general, 71.5 and 143 μg SO2 m−3 promoted the pathogenesis of the fungus whereas as 214.5 μg SO2 m−3 suppressed the blight.