Dissipation Pattern of Spirotetramat in/on Green Chillies

Two field studies were conducted to assess the dissipation pattern of spirotetramat in/on green chillies. Spirotetramat was sprayed thrice at fifteen d interval @ 60 and 120 g a.i. ha⁻¹. Fruit samples were collected at 0 (1 h after spraying), 1, 3, 5, 7, 10, 14, 21, 28 and 35 d after third spray. The initial deposit of spirotetramat was found to be 2.52 and 3.39 μg g⁻¹ from 60 and 120 g a.i. ha⁻¹ treatments, respectively in the first field experiment and 2.29 and 3.11 μg g⁻¹ respectively, in the second field experiment. The half life values worked out for different doses viz., 60 and 120 g a.i. ha⁻¹ were 2.43 and 3.22 d, respectively in the first field experiment 2.33 and 3.74 d, respectively in the second field experiment. Decline behaviour of disloudghable pesticide residues was computed following seven transformations and the best fit was first order for both treatments (Spirotetramat 150 OD at 60 and 120 g a.i. ha⁻¹) in two experiments.