Studies on the efficacy of some newly evolved fungicides against grain discolouration disease of rice (Oryza sativa L.) in West Bengal

Grain discoloration disease is presently becoming a serious threat in rice growing areas of India including West Bengal. The disease is causing both qualitative and quantitative losses of grain yield as well as reducing germination and increasing seedling mortality. Except other factors several micro organisms specially fungi play major role in development of this disease. On the background of these facts, the present investigation was carried out with some newly evolved and commercially available seven old and new generation fungicides. The experiment was conducted at farmer’s field in village Falta under South 24 Parganas District during Boro Season 2013-14 and 2014-15. Among seven fungicides tested, five fungicides were found effective in reducing disease incidence. Among five fungicides, Trifloxystrobin25% +Tebuconazole 50% WG was found to be best performing fungicide with minimum level of PDI and percentage of severely disease infected seed was also very less. The other four fungicides namely Carbendazim25%+Mancozeb 50%WS, Tricyclazole 18%+Mancozeb 62% WP, Tricyclazole75 % WP, Propiconazole13.9%+ Difeconazole13.9% EC had significant role in reducing PDI and percentage of disease infected seeds.