Efficacy of new fungicide molecules for managing sheath blight of rice under field conditions

AbstractSheath blight caused by Rhizoctonia solani is one of the most destructive diseases limiting rice productivity. This study evaluated the efficacy of seven fungicide formulations viz., mancozeb 50% + thiophanate methyl 25% WG; kasugamycin 5% + copper oxychloride 45% WP; azoxystrobin 5.1% + tebuconazole 9.1% + prochloraz 18.2% EC; fenoxanil 5% + isoprothiolane 30% EC; azoxystrobin 14 % + epoxiconazole 9 % SC ; picoxystrobin 7.05% + propiconazole 11.7% SC and tebuconazole 50%+ trifloxystrobin 25% w/w WG under artificial epiphytotic field conditions during kharif season of 2023 and 2024 at Punjab Agricultural University, Ludhiana. Among these, tebuconazole 50% + trifloxystrobin 25% @ 0.4g/L demonstrated highest efficacy, recording the lowest mean disease severity (12.78%) with the highest per cent disease control (84.25%) and significant increase in grain yield (36.60%) over the control. Picoxystrobin 7.05% + propiconazole 11.7% and azoxystrobin 14% + epoxiconazole 9% SC also showed promising results in both disease suppression and yield enhancement. A strong negative correlation (r = -0.95) was observed between disease severity and percent yield increase, highlighting the critical role of effective sheath blight management in improving rice productivity.