Efficacy of botanicals and fungicides against Alternaria leaf spot of black gram

Abstract

The study conducted with the aim of evaluating the potential of botanicals, fungicides and its combination in managing Alternaria leaf spot disease incited by Alternaria alternata in black gram showed maximum inhibition of mycelial growth (77.33%) with metiram + pyraclostrobin and minimum inhibition (27.28%) of mycelial growth with azadirachtin among all the tested treatments. In vitro it could successfully manage Alternaria leaf spot with 77.37 PDEC and 16.67 PDI. Minimum disease control was expressed by azadirachtin with 34.42 PEDC and 48.33 PDI. The combination of fungicide and the botanicals effectively controled the disease in short duration at low cost. Maximum black gram grain yield (0.90 kg plot-1) was obtained from field applied with combined foliar spray of fungicide and botanical and minimum grain yield was obtained with Foliar spray of azadirachtin (-0.5%) provided minimum (0.56 kg plot-1) grain yield.