The present study reports the variable antioxidant profile resulting from inducers/elicitors on mustard varieties against Alternaria brassicicola. An experiment was conducted with four inducers/elicitors viz., Benzothiadiazole (BTH), Hydrogen peroxide, Jasmonic Acid and Salicylic acid at three different concentrations to evaluate their effect against Alternaria leaf blight of mustard in four varieties viz., TBM-204, Bullet, B-54 and B-9. The pathogen A. brassicicola was inoculated at 15 DAS. An attempt was made to study the underline biochemical changes which may have their influence on induced resistance. The component of first line defense mechanism, catalase (CAT) and non-enzymatic antioxidants like ascorbic acid were found to be more prevalent in the plants treated with BTH followed by Jasmonic acid, Salicylic acid and Hydrogen peroxide. Among the varieties tested, these enzymes were more prevalent in TBM-204 and Bullet and less prevalent in B-54 and B-9

Mustard, Alternaria, catalase, ascorbic acid

The activation of antioxidant mechanism of the plant, where both, enzymatic antioxidant like catalase and non-enzymatic antioxidant like ascorbic acid were comparatively found to be more in TBM-204 and Bullet through which we can consider them as resistant varieties. The high levels of catalase played an important role in reducing the damage caused by the pathogen by dismutating O2•− and catalyzing H2O2 in resistant in coordination with the non-enzymatic antioxidants. However, it can be assumed that in B-54 and B-9 varieties an uncontrollable production of reactive oxygen species may be coupled with the less potentiality of antioxidant system created the oxidative stress. Here also noticed that with increase the age of the plant ascorbic acid content was also increased and more focused when the plants were inoculated with pathogen irrespective of inducers and their doses applied in four different cultivars. Here all the inducers increased the ascorbic acid content significantly in comparison to control and maximum in BTH whereas as minimum in H2O2

M. Divya, Srikanta Das and Sunita Mahapatra (2024). Evaluation of Antioxidants in Different Mustard Cultivars Against Alternaria Blight. Biological Forum – An International Journal, 16(6): 135-142.