Field Efficacy of Insect Growth Regulator, Pyriproxyfen against Sucking Insect Pests and Predatory Complex on Bt Cotton

摘要

The performance of pyriproxyfen 10 EC applied @ 75,100 and 125 g a.i. ha~(-1) against sucking insect pests and predatory complex in four different experiments at farmers' field on Bt cotton in comparison with untreated control and standard checks, i.e., diafenthiuron 50 WP @ 300 g a.i. ha~(-1) and ethion 50 EG @ 1000 g a.i. ha1 for white fly and imidacloprid 17.8 SL @ 25 g a.i. ha~(-1) as well as acetamiprid 20 SP @ 20 g a.i. ha~(-1) for jassid, is reported. Based on pooled mean of two years, the per cent reduction of white fly adults over control in pyriproxyfen 10 EC @ 100 and 125 g a.i. ha~(-1) was at par with ethion 50 EC at 7 and 10 days after spray (DAS) but was significantly inferior as compared to standard checks at 3 DAS. However, all the three pyriproxyfen dosages were significantly more effective against nymphal population of white fly at 1, 3 and 7 DAS as against standard checks. After 7 days of spray, the per cent reduction in white fly nymphs over control in pyriproxyfen 10 EC @ 100 and 125 g a.i. ha~(-1) was 90.0 and 91.4 per cent, respectively. All the three pyriproxyfen dosages did not prove better against jassid as compared to imidacloprid and acetamiprid. Seed cotton yield in pyriproxyfen 10 EC @ 100 and 125 g a.i. ha1 (23.76 and 23.96 q ha~(-1)) was at par with ethion 50 EC (24.09 q ha1). Moreover, pyriproxyfen was comparatively safe to predatory complex as against standard checks.