Chemically induced systemic acquired resistance in the inhibition of French bean rust

Abstract

IR (Induced resistance) is a security arrangement in the interior part of the plants to counterattack fungal, bacterial and viral pathogens or any pests. The apprehension has been appeared, and the system intensifies a resistance to the attack. In this research, efficacy of eight IR chemicals along with standard fungicide hexaconazole was evaluated against French bean rust with reference to alteration in biochemical constituents present in the plant under pot conditions. Minimum disease severity was recorded when plants were challenge inoculated after 20 days of treatment of IR chemicals. Minimum disease severity (8.50 %) was recorded in plants sprayed with KH2PO4 as compared to control. The application of IR chemicals triggered the activity of defence related enzymes (phenol, PO, PPO and PAL) in bean plants upon challenge inoculation with Uromyces appendiculatus. Under field conditions potassium dihydrogen phosphate sprays were found most effective in reducing the disease severity to 30.71 % followed by benzothiadiazole with 41.23 % disease severity though they were slightly less effective to standard fungicide hexaconazole.

Keywords

• French bean
• Phaseolus vulgaris
• Rust
• Uromyces appendiculatus
• IR chemicals
• Defense enzymes