Compatibility of new insecticides and fungicides against stem borer and leaf blast on semi-deep water rice

Field experiments were conducted on semi-deep water rice variety Jalpriya during kharif seasons of 2007–08, 2008–09 and 2009–10 to study the compatibility of insecticides viz., flubendiamide and spinosad; and fungicides viz., isoprothiolane Fugi 1 and carpropamid Protega alone and tank mixed in all possible combinations against rice stem borer and leaf blast disease. The experiment failed during 2008–09 due to excess flooding of field at late stage of the crop. The infestation of stem borer and leaf blast varied from 2.12 to 7.27% and 2.29 to 15.35%, respectively, during the period. The results of two kharif seasons indicated that insecticidal and fungicidal treatments alone were effective against stem borer and leaf blast, respectively, whereas the combination treatments were effective against both stem borer and leaf blast. The combination of flubendiamide 20 WDG @ 0.25 g/1+isoprothiolane Fugi 1 @ 1.5 ml/1 was most effective against both stem borer and leaf blast with 2.54 and 3.50% infestation, respectively, and fetched average grain yield of 23.53 q/ha. It was closely followed by flubendiamide 20 WDG @ 0.25 g/1 + carpropamid Protega @ 1.0 ml/I with 2.35% stem borer infestation, 4.03% leaf blast disease severity and 22.51 q/ha grain yield.