Elucidation of biochemical induction of host defence by biomolecules/ bioagents against Rhizoctonia solani Kuhn in soybean (Glycine max Merr.)

Abstract

An experiment was undertaken to understand the effect of elicitor compounds in imparting disease resistance to Rhizoctonia solani in Soybean. The results revealed that all the elicitor compounds were effective in managing the Rhizoctonia blight of soybean through the induction of host defence. Among the chemical inducers, isonicotinic acid was revealed to the most effective for inducing hydrogen peroxidase, ascorbate peroxidase, superoxide dismutase and polyphenol oxidase where as phenylalanine ammonia lyase and peroxidase was found to be highest in plants treated with salicylic acid and benzyl amino purine, respectively. All the elicitor biomolecules decreased the endogenous content of xylanase, laccase and cellulase to a greater extent, which have been reported as pathogenic determinants and assist pathogen attack. The bioagents were also effective in inducing the defence response to Rhizoctonia blight in soybean.