In-vitro sensitivity of Alternaria tenuissima isolated from marigold to different fungicides

Abstract

Leaf spot and flower blight caused by Alternaria tenuissima are economically important disease of marigold, resulting in significant reduction in flower yield and quality. The present study evaluated the in vitro efficacy of fifteen fungicides, including contact, systemic, and ready-mix formulations, against A. tenuissima using the poisoned food technique. Among contact fungicides, thiram exhibited the highest mycelial growth inhibition. Among the systematic fungicides hexaconazole and tricyclazole completely inhibited fungal growth. Among the redy-mix fungicides hexaconazole 4% + zineb 68% and hexaconazole 5% + captan 70% were the most effective, providing complete inhibition of mycelial growth. These findings indicate that hexaconazole-based fungicides blight under laboratory condition.