Inhibitory Effect of Plant Extracts on the Management of Bacterial Leaf Spot Pathogen (Xanthomonas axonopodis pv. Vesicatoria) Infecting Capsicum frutescens L.

Abstract

Objective: To evaluate the inhibitory effect of plant extracts on the management of bacterial leaf spot pathogen. Materials and method: Aqueous and alcoholic extracts of different parts of twenty plants including some medicinal plants were screened against the leaf spot bacteria, Xanthomonas axonopodis pv. vesicatoria infecting Capsicum frutescens. Extracts from different plant parts like leaf, bark, flower, fruit and seeds were prepared and used in three different concentrations of 500, 1000 and 2000 ppm, respectively. Results and conclusion: Extracts of Bixa orellana followed by Clerodendron inerme, Murraya konigii, Azadirachta indica, Melia azardirach and Parthenium hysterophorus were significantly superior to other extracts on growth inhibition of the pathogen. The inhibition was more at 2000 ppm compared to 1000 and 500 ppm concentration.