Efficacy of New Fungicides against Late Blight of Potato in Subtropical Plains of India

Abstract

The field efficacy of metiram 55%+pyraclostrobin 5% WG, iprovaliadacarb 5.5%+propineb 61.25% WP, dimethmorph 50% WP, dimethmorph 50% WP+ mancozeb 75%, WP, famoxadone16.6+cymoxanil22.1% SC along with existing standard fungicides were evaluated for management of late blight during 2012-15. The results revealed that treatment mancozeb 75% WP (0.2%- before appearance) followed by two more spray with mancozeb 75% WP (0.2%) +dimethomorph 50% WP (0.2%) at 7-10 days intervals showed less terminal disease severity (24.55%) with highest disease controlled (74.45%), which was at statistically par with treatment mancozeb75% WP (0.2%, before appearance) followed by cymoxanil 8+mancozeb 64 % WP (0.3%) with two more spray at 7-10 days intervals, with 27.56% terminal disease severity along with disease controlled 71.29%. The highest tuber yield (28.74t/ha) was observed with mancozeb75% WP (0.2% before appearance) followed by two more spray with dimethomorph 50% WP (0.2) at 7-10 days intervals with followed by 28.12 t/ha with mancozeb 75% WP (0.2%- before appearance) followed by two more spray with mancozeb 75% WP (0.2%) +dimethomorph 50% WP (0.2%) at 7-10 days intervals. One spray of mancozeb (contact fungicides: before appearance) and latter two sprays of translaminar/systemic+contact fungicides at 7-10 days interval give better results for management of late blight of potato.

Keywords

• late blight
• potato
• fungicides
• phytophthora infestans