Studies in relation to chitosan and its potential to enhance host resistance in Brassica juncea L. against Alternaria blight

Foliar spray of chitosan was applied on the leaves of 8 weeks old Brassica juncea L. (var. RLM 619) grown in pots. The study revealed that with 1 ppm concentration of chitosan, superoxide dismutase and with 5 ppm chitosan peroxidase and phenylalanine ammonia lyase were significantly increased with respect to control. Phenolic content in the leaves of treated plants also showed increase with both the treatments of chitosan. Defense related enzymes and phenolic content showed positive correlation i.e. increased with the elicitor application. As these enzymes and phenolics are involved in providing resistance to pathogens hence, may provide protection against Alternaria blight.