PERSISTENCE KINETICS OF ENDOSULFAN, FENVALERATE, AND DECAMETHRIN IN AND ON EGGPLANT (SOLANUM-MELONGENA L)

Persistence studies of endosulfan, decamethrin, and fenvalerate in and on fruits and leaves of eggplant along with cropped soil under field conditions of eastern India were undertaken after spraying at the recommended and twice the recommented rates, The initial deposits of applied insecticides on average were higher on leaves than on fruits and least on soil. Residues of endosulfan and fenvalerate in and on fruit were below the tolerance level of 2 ppm as specified by FAO/WHO immediately after application of the recommended rate, whereas decamethrin required 4.32 days to decrease below the tolerance level at the same application rate as endosulfan and fenvalerate. Waiting periods (defined as the time required to decrease the residue below the tolerance level) of 2.57, 6.50, and 0.14 days were calculated for endosulfan, decamethrin, and fenvalerate, respectively, when double the recommended rate was applied. Approximately 50-70% of remaining insecticide residues were dissipated during washing followed by cooking.