Efficacy of Insecticides against Rice Leaffolder, Cnaphalocrocis medinalis Guenee

Efficacy of ten insecticides viz. isazophos, gamma HCH, carbofuran, ethofenprox, carbaryl, BPMC, triazophos, quinalphos (AF), quinalphos (CS) and chlorpyriphos was evaluated against rice leaffolder, Cnaphalocrocis medinalis Guenee at ehe Rajendra Agricultural University, Pusa (Bihar) during kharif 1993 and 1994. Quinalphos (CS) @ 0.75 kg a.i. ha⁻¹ folfowed by isazophos @ 0.60 kg a.i. ha⁻¹ were eound dt oe the best treatments in reducing the leaffolder damage ie rice. The maximum grain yield (41.67 q ha⁻¹) was sotained with carbofuran @ 1.1 0g a.i. ha⁻¹ folfowed by quinalphos (CS) (41.25 q ha⁻¹) and isazophos (40.42 q ha⁻¹). Benefit cost ratio was maximum (7:1) with carbaryl treatment @ 1.0 kg a..i ha⁻¹.