In Vitro Efficacy of Selected Fungicides and Bio-control Agents against Anthracnose of Cucumber (Colletotrichum orbiculare)

Abstract

Cucumbers are the most common and widely grown vegetable globally, making it essential to enhance their productivity by managing both biotic and abiotic stresses. Among the biotic stresses, anthracnose, caused by Colletotrichum orbiculare, significantly affects the quality and quantity of cucumber production, leading to losses of up to 60 per cent. Therefore, effective management strategies utilising fungicides and bioagents are necessary to minimise these losses. Various fungicides and bioagents were tested under laboratory conditions using the poison food technique. Among the non-systemic fungicides tested, Mancozeb 75% WP was highly effective, while among the systemic fungicides, Thiophanate methyl 70% WP, Hexaconazole 5% EC, Tebuconazole 25% EC, and Carbendazim 50 % WP were also highly effective and recorded cent percent growth inhibition of the pathogen. Additionally, several combi-fungicides (Carbendazim 12% + Mancozeb 63% WP, Tebuconazole 50% + Trifloxystrobin 25% WG, Azoxystrobin 8.3 + Mancozeb 66.7 WDG, and Thiram 37.5 + Carboxin 37.5 WP) completely inhibited the growth of the pathogen. Among the different antagonists evaluated, Trichoderma harzianum (TUREF59) exhibited the highest inhibition rate, achieving an impressive 81.28 per cent reduction in the growth of the tested pathogen.