Comparative Efficacy of Different Fungicides against Late Blight Diseases of Potato incited by Phytophthora infestans (Mont.) de Bary and its Management

Abstract

Efforts made in present investigation to evaluate the concentration of few commonly used fungicides for their comparative efficacy against Phytophthora infestans (Mont.) de Bary- the incited of late blight, with a view to select the most effective fungicides for the disease management. The highest (99.70) percentage of disease control and the highest yield (26.68 ton/ha) were recorded on fungicides containing 3.5 mg/L Sunoxanil 72 WP (Cymoxanil 8%+Mancozeb 64%) with 3.0 ml/L Contaf 5EC (Hexaconazol 5%) during 2015-2016. The lowest (75.68) percentage of disease control and the lowest yield (15.67 ton/ha) were recorded on fungicides containing 2.0 mg/L Ridomil MZ 72 (Metalaxyl 8%+Mancozeb 64%) with 1.0 ml/L Autostin 50 WDG (Carbondaxim 50%) during 2014-2015. It was concluded that Sunoxanil 72 WP (Cymoxanil 8%+ Mancozeb 64%) acted as the best fungicide when applied as prophylactic measures. Sunoxanil 72 WP (Cymoxanil 8%+ Mancozeb 64%) was combined with Contaf 5EC (Hexaconazol 5%) showed the best result when applied as curative measures. On the other hands when Actiphose (Phosphorous acid)) was used with Mancozeb (Indrofil M-45) showed comparatively better performance. Plant growth as well as its yield gradually decreased due to the application of Carbondaxim. Keywords Potato; Late blight; Management; Hexaconazole; Mancozeb; Sunoxanil 72 WP; Autostin50 WDG; Actiphose; Ridomil MZ 72;