Persistence and Dissipation of Triazophos in Bitter Gourd

Triazophos (Trazan 40 EC) @ 0.06% a.i. (1.5 ml/lt. of water) and 0.12% a.i. (3 ml/lt. of water) were sprayed on bitter gourd at fruiting stage during kharif, 2003. First spray was done at 45 days after sowing and next at 15 days after first spraying. Fruit samples for residue estimation were collected after second application of pesticide. The maximum initial residue of 0.31 and 0.79 ppm were recorded after 2 h of second spray. No residue could be detected after 7 days following application at 0.06% a.i./ha and after 15 days of spraying following spray at double the recommended dose. Half-life values of Triazophos used @ 0.06% and 0.12% a.i. were found to be 0.75 and 1.55 days, respectively.