Biochemical Changes Induced in Amorphophallus in Response to Treatment with Biocontrol Agent and Pathogen

摘要

Elephant foot yam is a popular vegetable widely grown in the tropics, mainly infected by collar rot caused by Sclerotium ro/fsii. Biological control is an important strategy to stimulate the defense system of the plant for the control of the pathogen.Potential of Trichoderma harziamim (Tr9), an effective antagonistic isolate screened in vitro, to induce systemic resistance was tested in elephant foot yam. Biochemical changes in T. harziamim treated plants, S.rolfsii inoculated plants and healthy plants were assayed before (S_1) and after (S_2) pathogen challenge. Treatment with T. harziamim and challenge inoculation of S.rolfsii enhanced induction of defense compounds such as peroxidase (PO), polyphenol oxidase (PPO), phenylalanine ammonia lyase (PAL), PR proteins (chitinase and glucanase) and total phenols when compared to control. T. harziamim treatment singly and also along with the pathogen significantly increased the activity of all the defense compounds under study in elephant foot yam. Theobservations revealed the role of 71 harziamim in stimulating systemic resistance by eliciting the production of defense enzymes. This is the first report of characterizing the biochemical defense response of elephant foot yam in response to Trichodermaand S.rolfsii