In vitro efficacy of fungicides against Alternaria chlamydospora causing leaf spot of okra

Abstract

Okra (Abelmoschus esculentus (L.) Moench) crop is being affected by several fungal, bacterial, viral and nematode induced diseases. However, leaf spot, caused by Alternaria chlamydospora has been common occurrence, causing quantitative as well as qualitative losses in okra. Therefore, present in vitro study was planned in CRD with two separate experiments (Contact and systemic and combi-fungicides) in vitro, in 10 treatments replicated thrice, to assess the efficacy of fungicides against Alternaria chlamydospora, at the Department of Plant Pathology, College of Agriculture, Latur (MS), during 2017-18. Results revealed that All of the seven systemic and nine contact / combi-fungicides evaluated in vitro were found fungistatic and exhibited significant mycelial growth inhibition of A. chlamydospora, causing okra Alternaria leaf spot. However, the systemic fungicides viz., Hexaconazole 5% EC, Tebuconazole 25.9% EC, Difenconazole 25% EC and Propiconazole 25% EC were found most effective against the test pathogen. Whereas, among contact / combi – fungicides the most effective fungicide found were Carbendazim 25% + Mancozeb 50% WS, Carboxin 37.5% + Thiram 37.5% WS, Tebuconazole 50% + Trifloxystrobin 25% WG, Propineb 70% WP and Mancozeb 75% WP.