Abstract

The effect of spirotetramat 150 OD (insecticide) application on sucking pests (whitefly, aphids, thrips and mealy bug) and predators (spiders, coccinellids and chrysopids) was investigated in transgenic Bt cotton and non-transgenic cotton agroecosystems at Tamil Nadu Agricultural University, Coimbatore. Transgenic cotton did not cause changes in population of pests and did not reduce number of predators considerably. Pesticide application decreased number of whitefly, aphid and mealy bug population significantly on both transgenic and non-transgenic cotton plants. Reduction in the population of predators was observed immediately after application. Later the population of predators started increasing gradually. However the population was found to be less than that of untreated plots. The result revealed that, transgenic Bt cotton did not affect sucking pest populations and did not cause considerable reduction in predator populations. The performance of spirotetramat on the incidence of sucking pests and abundance of natural enemies was similar on both Bt and non Bt cotton.

Keywords: Spirotetramat, 150 OD transgenic cotton, sucking pests, predators