Antifungal efficacy of fungicides, botanicals and bioagents against Alternaria leaf blight of chrysanthemum

Abstract

The present investigation was conducted to test the in vitro efficacy of fungicides, botanicals and bio-agents against Alternaria alternata causing leaf blight disease of chrysanthemum. Seven fungicides evaluated under in-vitro condition showed that Hexaconazole, Difenconazole and Azoxystrobin + Difenconazole at all concentrations viz.,0.1, 0.2 and 0.3% completely inhibited fungal mycelial growth followed by Tebuconazole + Trifloxystrobin at 0.3% concentration. Among the botanicals Garlic clove extract @ 10% was found most effective with 83.67% fungal mycelial inhibition against Alternaria alternata. Bioagent tested by dual culture technique revealed that Trichoderma harzianum and Trichoderma asperellum was the best antagonistic against Alternaria alternata by inhibiting mycelial growth of A. alternata 79.25% and 77.15% respectively.