Dissipation of Profenophos, Triazophos and Acephate in/on Okra Fruits

With a view to study the dissipation of profenophos, triazophos and acephate in/on okra field experiment conducted at Regional Research station, Anand Agriculture University, Anand during Kharif 2013. The experiment was carried out in Randomized Block Design (RBD) with three replications along with a control plot. In okra, two sprays of profenophos, triazophos and acephate insecticides were applied during fruiting stage @ 500 g a.i. ha−1, @ 500 g a.i. ha−1 and 560 g a.i. ha−1, respectively at an interval of 10 days. An untreated control was maintained for comparison. Immediately after the last application (i.e. 1hr after spray), fruit samples were drawn for 0 day. The subsequent sampling was carried out on 1st, 3rd, 5th, 7th and 10th day. The result revealed that in okra fruit initial deposits of profenophos, triazophos and acephate were 4.472, 4.900, 5.377 μg g−1 respectively, which dissipated to 1.222, 2.282 and 2.870 μg g−1 within the 24 hrs. Residue of profenophos, triazophos and acephate reached BDL within 3, 5 and 7 days, respectively. Dissipation of profenophos, triazophos acephate showed monophasic first order kinetics. The Half-life value for profenophos, triazophos and acephate were 0.64, 0.74 and 1.26, respectively.