Persistence of Endosulfan Residues In/On Knol-Khol (Brassica Caulorapa L,) At Medium Altitude Hills

The spraying of endosulfan 0.075, 0.1 and 0.2 percent resulted into average deposits of 7.5, 10.6 and 15.3 ppm on knobs and 13.2, 46.3 and 61.8 on leaves respectivley. These deposits reached below tolerance level of 2 ppm in 7–10 days. The half life values ranged from 1.3 to 3.3 days and waiting period from 2.5 to 9.6 days in field condition. When knobs were stored in a room and in fridge the persistence of endosulfan was longer than field condition. Washing and cooking could mitigate the residues below tolerance level only at 0.07% concentration.