Dissipation and kinetic studies of fluopyram and trifloxystrobin in chilli

The dissipation patterns of fluopyram, trifloxystrobin and their metabolites in green chilli fruits were studied after application of fluopyram and trifloxystrobin at fruiting stage at recommended doses (150 +150 g a.i. ha−1) and double the recommended doses (300 +300 g a.i. ha−1). After application, chilli samples were collected at the 0, 3rd, 5th, 7th, 10th, 15th, 21st, 25th, and 30th day after spray. The initial deposits of fluopyram and trifloxystrobin in chilli fruits was recorded to be 5.57 and 1.59 mg kg−1 at recommended dose and 8.84 and 3.27 mg kg−1 at double dose, respectively. Residue of the metabolite of Fluopyram (fluopyram bezamide) was observed to be below LOQ at both the doses whereas, in case of trifloxystrobin’s metabolite (CGA 321113), the residues were detected at 0th and 3rd day but in later sampling the residues reaches below LOQ level. Based on the dissipation studies it was found that fluopyram dissipated by first order kinetics whereas, trifloxystrobin residues dissipated by zero order kinetics. The half-life of fluopyram was found to be 1.23 and 2.38 days and that for trifloxystrobin were 1.27 and 4.88 days at recommended and double dose respectively. A waiting period of 28 days is suggested for safe consumption of green chilli applied with the mixture of these pesticides.