Role of exogenous application of elicitors in Brassica species

Role of elicitors viz., salicylic acid (SA) and benzothiadiazole (BTH) on induction of resistance to combat Alternaria blight in Brassica juncea (cv. PBR-91) and B. napus (cv. GSC-6) was studied. Field trials were conducted in 2011-12 and 2012-13 to investigate the effect of different concentrations of elicitors on antioxidative enzymes viz., peroxidase (PO), phenylalanine ammonia lyase (PAL), superoxide dismutase (SOD); pathogenesis related (PR) proteins viz., chitinase, ¿-1,3-glucanase; phenolics; pigments; ascorbic acid and sugars in both Brassica species. Elicitor treatments enhanced the activities of defense related enzymes and phenolic contents as compared to water sprayed control plants. Elicitor treatments also exhibited maximum contents of photosynthetic pigments, ascorbic acid, total soluble protein, free amino acids, total sugars and reducing sugars than control in both the species. Among all the elicitor treatments, combinations of elicitors, i.e., BTH (3 ppm) + SA (33 ppm) and BTH (7 ppm) + SA (17 ppm), were most effective.