1Department of Soil Science and Agricultural Chemistry, College of Agriculture
2All India Network Project (AINP) on Pesticide Residues, PRRAL, Kerala Agricultural University
3CSS on MPRNL, AINP on Pesticide Residues, College of Agriculture, Vellayani, Thiruvananthapuram695522, Kerala, India
*Corresponding author E-mail: thomas.george@kau.in
Online published on 15 October, 2020.
Adsorption- desorption behaviour of flupyradifurone, a systemic insecticide of the class butenolide, is reported under laboratory conditions on a sandy loam soil and the soil amended with 0.5 per cent farmyard manure, using a batch equilibration technique with 0.01 mol L−1 CaCl2 solution in the concentration range 1 to 5 mg L−1. The adsorption isotherm was L type. The values of Kf were 2.46 for soil and 2.57 for the amended soil, revealing a slightly higher adsorption in the amended soil. On an average, 15.68-22.77 per cent of the adsorbed flupyradifurone got desorbed in three desorption cycles at different concentrations, while in for the amended soil about 14.39-26.00 per cent got desorbed. The hysteresis coefficient H varied from 6.9-3.8 and 7.6-4.0 for the normal and the amended soils, showing a higher rate of desorption than adsorption.
Flupyradifurone, Adsorption, Desorption, Sandy loam soil, FYM amended soil