INTEGRATED DISEASE MANAGEMENT OF CHILLI ANTHRACNOSE

Abstract

ABSTRACT The present studies were undertaken to investigate the effect of bioprotectant, plant based chemical like Salicylic acid and silicon based nutrient Potassium silicate against the anthracnose or ripe fruit rot of chilli (Capsicum annuum L.) incited by Colletotrichum capsici (Sydow.) Butler and Bisby in chilli var. K2. The chilli anthracnose disease susceptible variety Kovilpatti-2 (K2) grown in pots and field trial were used for the study. The plants were given artificial inoculation by spraying the spore suspensions after pinpricking the fruits with adequate spore load at 90-days after transplanting for fruit rot incidence assessment. The crop was maintained in a poly house with frequent spraying of water to provide adequate moisture and relative humidity to enable successful infection by the pathogen. Three replications for each treatment and a control were maintained. The fungicide mancozeb @ 0.25 per cent was used for comparison and the standard agronomic practices as recommended by the State Agricultural Department were followed. The plant activator and silicon-based nutrient were sprayed as individual as well as combined approach manner. Seed treatment with Pseudomonas fluorescens @ 10 g/kg of seeds in all the treatments except comparison fungicide and control treatments. Among the various treatments, seed treatment with Bio protectant, foliar application of Salicylic acid @ 50 ppm on 40 days after transplanting (40 DAT) and foliar application of Potassium silicate @ 3 % on 60 DAT recorded the minimum disease incidence and increased fruit length, fruit weight, fruit per plant, branches per plant, plant height and germination percentage when compared to control and Comparison fungicide Mancozeb. The activity of plant defense enzymes like Peroxidase, polyphenol oxidase and Phenylalanine ammonia lyase increased up to 5th day of sampling in plants treated with Bio-protectant, resistance inducing chemical along with potassium silicate and challenged inoculated with the test pathogen. Also, the same treatment significantly decreased the disease severity and increased the growth and yield parameters when compared to control and comparison fungicide under the field trials.