Evaluation of fungicides, botanicals and bio-agents against Alternaria alternata incitant of leaf spot of soybean

Abstract

Alternaria leaf spot of soybean is an important disease of soybean inflicting heavy losses in now days. The present investigation was carried out to test the efficacy of fungicides, botanicals and bio-agents in vitro. Among fungicides tested, Hexaconazole, Propiconazole, Propineb and Cymoxonil + Mancozeb showed 100 percent mycelial inhibition of Alternaria alternata. Among the botanicals evaluated against Alternaria alternata in vitro, Garlic clove extract@ 10% was found most effective giving (87.50%) inhibition against Alternaria alternata. Bio-efficacy of bioagent also tested by dual culture technique and results revealed that Trichoderma harzianum and Trichoderma asperellum gave the best effect against Alternaria alternata forming maximum percent mycelial inhibition i.e. 79.65% and 76.55%.