none In field plot tests at Dharwad, in 1978-80, two synthetic pyrethroids viz., permethrin (125, 150 and 200 ppm) and cypermethrin (50 and 100 ppm), monocrotophos (1000 ppm) and endosulfan (1000 ppm) (tested in 1979-80 only), were evaluated for their toxicity by spray applications to Rogas aligarhensis Qadri, a larval parasite of spotted cotton bollworm, Earias vittella (Fabricius). All the insecticides tested had significantly reduced the population of the parasite as judged by the number of pupae collected per plant. During 1978-79, permethrin at 125 and 150 ppm was on par with permethrin at 200 ppm but significantly better than cypermethrin (at both the concentration levels) and monocrotophos. However, in 1979-80 all the insecticides had similar effect on the parasite. In general, population build up of the parasite was earlier and in greater number in case of permethrin at 125 and 150 ppm which seem to be useful and worth while trying in the integrated pest management of cotton.