Monitoring of Insecticide Residues in IPM and Non-IPM Fields of Okra and Brinjal

Okra and brinjal fruits from non-IPM and IPM fields before their delivery at the market were collected and analysed for residues of insecticides viz., chlorpyriphos, cypermethrin, monocrotophos, dimethoate and deltamethrin, widely used on these crops in village Raispur, Ghaziabad district (U.P) during 2003–04 and 2004–05. The soil samples from fields before sowing and after harvesting of both the crops were also analysed for chlorpyriphos during 2003–04. The residues of chlorpyriphos in soil (0.41 μg g⁻¹) before start of okra trial, increased to 4.22 and 1.14 μg g⁻¹ at harvest time in non-IPM and IPM fields of okra crop, respectively. In brinjal crop, the chlorpyriphos was non-detectable (ND) in soils of both IPM and non-IPM fields before and after trial. During 2003–04, the residues of chlorpyriphos and cypermethrin in okra fruits were found to be 0.10 mg g⁻¹ and ND for IPM trials and 5.75 and 0.63 μg g⁻¹ for non-ipm fields, while that of monocrotophos in brinjal fruits were found to be ND and 1.24 μg g⁻¹ for IPM and non-IPM fields respectively. During 2004–05. residues of chlorpyriphos. imidacloprid, monocrotophos, dimethoate, megha (chlorpyriphos + cypermethrin) and in. mixtures (chlorpyriphos. cypermethrin, monocrotophos and dimethoate) in okra fruits from non-IPM fields were 1.54, 6.72, 3.76, 1.45. 3.59, 5.80 and 0.68, 6.65, 1.80, 4.79 and 4.65 μg g⁻¹, respectively at one day after spray and were higher than residues from IPM fields indicating application of higher doses by non-IPM farmers. Residues of cypermethrin. imidacloprid, monocrotophos megha (chlorpyriphos + cypermethrin) in brinjal fruits collected from non-IPM fields were found to be 1.74, 8.5, 2.85, 6.76 and 1.10 μg g⁻¹, respectively at one day after spray and were invariably higher than IPM samples. The produce at harvest from IPM fields was safe to consume. The residue levels of insecticides applied in okra and brinjal in IPM trials were found to be below maximum residue limit (MRL).