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Following four foliar applications of Nativo 75 WG (trifloxystrobin 25% + tebuconazole 50%) on grapes @ 175 and 350 g/ha, resulting in active applications of trifloxystrobin @ 43.75 and 87.5 g a.i./ha and that of tebuconazole @ 87.5 and 175 g a.i./ha, the average initial deposits of trifloxystrobin were observed to be 7.76 and 15.53 mg/kg, respectively, at single and double the application rates. These residue levels dissipated to >85% after 10 days of its application at both the dosages. Similarly, the average initial deposits of tebuconazole were observed to be 13.84 and 26.55 mg/kg at single and double the application rate, respectively. These residue levels dissipated to >90% after 10 days of application at both the dosages. The half-life (t(1/2)) periods of trifloxystrobin on grape leaves were observed to be 2.92 and 3.48 days at single and double application rates, respectively, whereas these values were 2.68 and 3.96 days for tebuconazole. Ripe grape berries and soil samples collected at harvest which happened to be 34 days after the last application, did not show the presence of residues of trifloxystrobin and tebuconazole at their determination limit of 0.01 and 0.02 mg/kg, respectively.

Dissipation of trifloxystrobin and tebuconazole were studied following two applications of a combination formulation of Nativo 75 WG (trifloxystrobin 25% + tebuconazole 50%) @ 250 and 500 g ha(-1) at 10 days interval. Samples of chili were collected at 0, 1, 3, 5, 7, 10 and 15 days after the last application. Red chili and soil samples were collected after 20 days of last application. Half-life period for trifloxystrobin were found to be 1.81 and 1.58 days and for tebuconazole these values were observed to be 1.37 and 1.41 days, respectively, at single and double the application rates. Trifloxystrobin residues dissipated below its limit of quantification (LOQ) of 0.01 mg kg(-1) after 5 and 7 days, respectively, at single and double the application dosages whereas tebuconazole residues took 7 and 10 days, respectively. Red chili & soil samples collected after 20 days did not reveal the presence of trifloxystrobin and tebuconazole at their determination limit of 0.01 mg kg(-1).

Indoxacarb residues were estimated by employing standardized QuEChERS technique in cabbage following three applications of Avant(R) 14.8 EC @ 52.2 and 104.4 g a.i. ha(-1). The average recoveries of indoxacarb on cabbage for fortification levels of 0.01, 0.05 and 0.1 mg kg(-1) were observed to be 83.93, 89.86 and 95.40%, respectively, with relative standard deviation of 1.21, 1.53 and 2.23. The method was also validated with respect to parameters of linearity, precision and limit of quantification (LOQ). The LOQ for cabbage was found to be 0.01 mg kg(-1). The average initial deposits of indoxacarb on cabbage were observed to be 0.18 and 0.39 mg kg(-1), respectively, at single and double the application rate. These indoxacarb residues dissipated below its LOQ of 0.01 mg kg(-1)after 7 and 10 days, respectively, at single and double dosages. Half-life of indoxacarb was observed to be 2.88 and 1.92 days, respectively, at recommended and double the recommended dosages.