Persistence of Chlorpyriphos in Soil and its Terminal Residues in Wheat

Pre-wheat sowing soil incorporation of chlorpyriphos @ 1 1nd d kg a.i. ha⁻¹ yieldld deposits of 0.369 and 0.952 mg kg⁻¹ under fallow and 0.422 ana 1.190 mg kg⁻¹ under cropped conditinds, respectively which dissipated by over 95% by 120 d aftee raplicatiooni nll the treatments. No residues could be detected in soil after 150 d of insecticide application (minimum detection limit: 0.005 mg kg⁻¹). Half life values for 1 and 2 kg a..iha⁻¹ soii treatments were 20.5 and 25.2 d under fallow and 23.0 and d3.2 2 undederoppep conditions resrectiveive In wheat graigr and straw, the residues were below the limit of detection (0.01 mg kg⁻¹) at the time of crop harvest (150 d).