Management of foliar diseases of Bt cotton using chemical fungicides and biocontrol agent

Abstract

To assess the efficacy of different chemical fungicides and a bioagent Pseudomonas fluorescens (TNAU-Pf1) against major foliar diseases of cotton two field trials were conducted at Cotton Research Station farm, Veppanthattai, Perambalur District, Tamil Nadu India. The results on field evaluation of different fungicides (Experiment I) revealed that the foliar application of propiconazole (0.1%) on 60, 90 and 120 DAS was effective in controlling the foliar diseases viz., Alternaria leaf blight, leaf spot, grey mildew and bacterial blight and recorded a maximum seed cotton yield of 23.10 q/ha. In the second experiment, the talc-based formulation of P. fluorescens was applied as seed treatment and foliar spray at different time intervals. The results revealed that seed treatment with P. fluorescens @ 10 g /kg + foliar spray @ 0.2 per cent on 50, 65, 80, 95, and 110 DAS gave better control of the foliar diseases and recorded higher seed cotton yield (21.8 q/ha) compared to chemical fungicide.