Field evaluation of selective systemic formulations against sucking insect pest complex and their natural enemies on a transgenic Bt cotton

Sucking insect pest complex,comprising of aphids aphis gossypii glover,jassids amrasca devastans distant,whiteflies bemisia tabaci gennadius,thrips thrips tabaci lindeman,red cotton bugs dysdercus koenigii walk and dusky cotton bugs oxycarenus hyalinipennis costa,has been a challenge on transgenic (bt) cotton crop all over the world. this study assessed the field efficacy of six commercial insecticides viz.; blaster 72.5%wp (imidacloprid + acephate),bugatti 50%sc (imidacloprid + bifenthrin),confidor 20%sl (imidacloprid),jozer 202sl (imidacloprid + acetamiprid),pouch 35%sc (pyriproxyfen + etofenprox) and senator 41.6%ec (imidacloprid + pyriproxyfen) against sucking insect pest complex and also determined their side-effect on natural enemies of these insect pests such as ants,parasitoid wasps,green lacewings and coccinellid beetles. experimental design was split-plot randomized complete block with three replications for each treatment. transgenic (bt) cotton variety (fh-118) was sown. insecticide formulations were applied according to their field recommended dose rates upon attainment of etls of most of the sucking insect pests. data regarding insect populations were recorded 3 and 7 day post treatment. results revealed that confidor proved to be most effective systemic insecticide against all insect pests,followed by pouch,senator,blaster,bugatti and jozer. however,confidor,jozer,bugatti,blaster and senator showed a top-down effect on beneficial insects causing 50-90% reduction in their populations,while pouch showed minimum effect (< 50% reduction) on the population of beneficial insects and proved to be relatively safe. all insecticide formulations tested exhibited = 50% reduction in the population of green lacewings. similarly,whitefly parasitism recorded in the confidor and jozer plots was very close to that of control plots for both post-treatment observations. based on these findings,confidor and jozer are recommended to be considered for their integration in sucking pests’ management strategies on transgenic crops such as bt cotton. copyright 2017 zoological society of pakistan.