Management of Early Blight of Tomato (Alternaria solani) through Application of Plant Extracts and Fungicides

Abstract

In the present work, plant extracts and fungicides were evaluated for an effective management of early blight of tomato caused by Alternaria solani under in vitro and in vivo condition and determine yield losses and cost benefit ratio. The present investigations revealed that Hexaconazole and Azoxystrobin were most effective it produced 100.0 per cent mycelia growth inhibition, whereas minimum mycelia growth was recorded in Difenoconazole (1.89 mm) and Trifloxystrobin + Tebuconazole (4.0 mm). Calotropis gigantea extract @ 20 per cent was found best as it produced 77.0 per cent mycelia growth inhibition of Alternaria solani followed by Azadirachta indica (74.26%).The effect of foliar spray of Calotropis gigantea @ 20.0 per cent was found the best for managing early blight of tomato in field condition as minimum disease intensity (39.83%) and highest yield (15.25 t/ha) was recorded with highest benefit cost ratio (1.62). The minimum disease intensity (15.43%), highest yield (22.40 t/ha) and highest benefit cost ratio (2.75) was recorded in Hexaconazole @ 0.1 per cent followed by Azoxystrobin @ 0.1 per cent.