MICROBIAL AND HERBIVORE INDUCED PHYTOCHEMICAL CHANGES IN OKRA AGAINST SHOOT AND FRUIT BORER, EARIAS VITTELLA (FAB.)

Microbial andherbivore induced phytochemical changes were studied in okra variety, Arkaanamika and hybrid, CoBhH1, againstshoot and fruit borer, Earias vittella. Induction was done either bymicrobial alone (microbial talc-based bioformulation Pseudomonas fluorescens(Pf1), Beauveria bassiana B2 isolate, Pf1+B2 consortia) or by bothmicrobial and herbivore (E. vittella infestation). Herbivore alone infestedplants served as infested control and undamaged plants left as absolutecontrol. Biochemical pathways encompassing induced resistance viz.,phenols and oxidizing defense enzymes such as peroxidase (PO), phenylalanineammonia lyase (PAL) and polyphenol oxidase (PPO) were assessed to envisage thedevelopment of induced resistance. Accumulation of phenol was high in Pf1+B2consortia inoculated plants as against absolute control in variety, Arkaanamika and hybrid, CoBhH1. Inoculation with both microbial consortia and E.vittella caused 9.8 times increased accumulation of phenolics in ArkaAnamika and 8.6 times in CoBhH1. Defense enzymes activity was alsosignificantly higher in Pf1 + B2 consortia treated plants as against absolutecontrol. Further, infestation by E. vittella resulted in the enhancementof accumulation of phenols, induction of PO, PAL and PPO activity. In absolutecontrol, CoBhH1 had higher phenolic accumulation and increased activity ofdefense enzymes than Arka Anamika.