All fifteen insecticides tested significantly reduced pest levels. Permethrin 25 e.c. @ 150ga.i./ha proved significantly superior than other insecticides during both the years when observed 3 days after treatment but was at par with deltamethrin 2.8 e.c. and fenvalerate 20 e.c. when observed 7 and 15 days after spraying. Isofenphos was least effective, however, it did not differ significantly from phosalone during 1981–82 and fenitrothion, triazophos and phosalone during 1982–83. Maximum and the minimum cost benefit ratios of 1 : 10.6 and 1 : 4.0 were obtained in gamma BHC and fenvalerate treated plots respectively.