Investigation on the chemistry and environmental fate of some new generation pesticides

Abstract

P newlinelant protection chemicals known as pesticides are used for management of crop losses newlinedue to pest damage and thereby play a vital role in achieving the food security. newlineHowever, the continuous and indiscriminate use of synthetic pesticide facing ecological newlinechallenges due to their toxic residues in food and environment. Therefore, to ensure food and newlineenvironmental safety, efforts have been directed towards development of newer eco-friendly newlinemolecules with little or no hazard to human health and environment. Botanicals in this regards as newlinecrude extracts and active molecules may have potential to act as alternative to synthetic newlinepesticides and may lead to safe, easy and environment friendly method, for crop protection. newlineInsect infestation in rice, one of the important cereal food crops in the world is a serious newlineproblem. newlineAcetamirid newline(N-[(6-chloro-3-pyridyl) newlinemethyl]-N -cyano-N-methylacetamidine) newlinebelonging to neonicotinoid group of new generation insecticides is widely used as foliar newlineapplications in a number of crops including paddy. To understand the dissipation of acetamiprid newlineresidues in paddy (Variety: Satabdi), a field experiment was conducted in Nadia, West Bengal newlinefollowing twice application of Acetamiprid 20% SP at 10 g (T 1 ), 20 g (T 2 ) and 40 g (T 3 ) a.i. ha -1 newlinealong with untreated control (T 4 ). Residue analysis of acetamiprid in paddy (leaf, grain, husk, newlinestraw and soil) was conducted using High Performance Liquid Chromatograph (HPLC) with UV newlinedetector at 0.05 mg kg -1 (LOQ) of 0.05 mg kg -1 . The recovery of acetamiprid from fortified newlinepaddy sample was obtained in the range of 81.8% to 93.1% (for leaf, grain, husk and straw) and newlinefor soil it was 87.2% to 94.3% at LOQ and upper two levels of LOQ (0.10 and 0.50 mg kg -1 ). newlineThe initial residue of acetamiprid (0.11-0.99 mg kg -1 ) dissipated following 1 st order reaction newlinekinetics with the half life of 1.5-1.8 days in paddy leaf and 1.3-1.4 days in soil. In harvestedsamples of paddy straw, grain and soil the residue was below LOQ.