Sorption – desorption of imidacloprid insecticide on Indian soils of five different locations

Authors : Shailendra Singh CHAUHAN, Anjana SRİVASTAVA, Prakash Chandra SRİVASTAVA, Ankita VERMA

Pages : 107-113

View : 13 | Download : 8

Publication Date : 2013-06-01

Article Type : Research Paper

Abstract :Sorption-desorption processes govern the movement of all chemicals including pesticides in soils.  The present investigation was undertaken to study the sorption-desorption of imidacloprid, using a batch method, on soils of five different location of India. Sorption data were fitted to Freundlich isotherm. The log K value was the highest for loam type soil insert ignore into journalissuearticles values(1.830); and the lowest for clay type soil insert ignore into journalissuearticles values(1.661);. The value of 1/n was the maximum for silt loam soil insert ignore into journalissuearticles values(0.909); but minimum for loam soil insert ignore into journalissuearticles values(0.723);. Simple correlation analysis indicated that among soil properties only electrical conductivity showed a higher but marginally non-significant negative correlation with log K insert ignore into journalissuearticles values(r = -0.826); indicating that higher concentration of solutes solutes are conducive to low sorption capacity of soil. The desorption data conformed to two surfaces Freundlich desorption isotherm. The values of 1/n 1 ` corresponding to easily desorbed fraction of imidacloprid showed significant negative correlation with soil pH insert ignore into journalissuearticles values(r = -0.886, significant at p ≤0.05); but significant positive correlation with clay content insert ignore into journalissuearticles values(r = 0.980, significant at p ≤0.01);. The desorption index for easily desorbed fraction of imidacloprid insert ignore into journalissuearticles values(n 1 ’/n); also had significant negative correlation with soil pH insert ignore into journalissuearticles values(r = 0.953, significant at p ≤0.05);. From cumulative desorption data, it appeared that bioavailability of imidacloprid would be lower in neutral soil than acidic or alkaline soils.
Keywords : sorption desorption, imidacloprid, soil, loam, clay, Freundlich isotherm