SushilGodara, Rajni2019-11-212019-11-212019http://krishikosh.egranth.ac.in/handle/1/5810135868Dissipation and decontamination behaviour of a ready mix fungicide (azoxystrobin + difenoconazole) was studied in tomato fruits and soil (at harvest). For this field experiments were carried out at research farm department of Entomology, CCS Harayana Agricultural University, Hisar. Tomato variety HS-102 was grown during the kharif season. For laboratory work, samples were collected at 0 (1 hr after application), 1, 3, 5, 7, 10 and 15 days after treatment, exclusively on random basis. The sample preparation method involving extraction with acetone provided 81.25 to 99.09 per cent recoveries for both the pesticides with precision RSD within 5-9% estimated at the limits of quantification (LOQ for azoxystrobin was 0.01 mg kg-1 and for difenoconazole it was 0.05 mg kg-1) and higher fortification levels. To study dissipation kinetics, the ready-mix fungicide was sprayed at dosage of 1 mL/L (single dose) and 2 mL/L (double dose). The residues were analysed on gas chromatograph equipped with electron capture detector (ECD). The dissipation kinetics followed first order kinetics with half-lives of 3-5 days for azoxystrobin and 1-3 days for difenoconazole. Decontamination of acquired residues by various culinary processes was quite efficient in minimising the residue load of both the fungicides. Maximum reduction was observed in case of washing followed by peeling (>75%) then washing followed by boiling (> 50%) and finally by washing with tap water (>30%). The residues of azoxystrobin and difenoconazole were confined mostly in the tomato peel. So peeled tomatoes are almost free from contamination of these fungicides and are safe for human beings.ennullThesis