All India Co-ordinated Research Project on Pesticide Residues, Tobacco Projects, Gujarat Agricultural University, Anand Campus, Anand-388 110, Gujarat, India.
Online published on 31 October, 2011.
Persistence of chlorpyriphos and endosulfan was studied in a sandy loam soil in a wheat field during Rabi 1997–98 at BTRS Farm, Gujarat Agrrcullural University, Anand, Gujarat. Seed dressing of wheat with chlorpyriphos @ 0.9 and endosulfan @ 2.45 g a.i. kg−1 ssed, showed initially low levels of their residues in surface soil, which gradually built up with time, reached maximum on the 20th and 30th d, respectively, and declined thereafter. Application of the respective insecticides through irrigation @ 400 and 700 g a.i. ha−1 resulted in comparatively low levels of their residues in soil. Chlorpyriphos when applied through irrigation dissipated gradually with half-life of 8.3 d, however, endosulfan residue built up till 20th d and declined thereater. The residues of both the insecticides were absent in wheat grain and straw at harvest.
Chlorpyriphos, endosulfan, dissipation, residues
