نوع مقاله : مقاله پژوهشی
1 دانشجوی سابق کارشناسی ارشد پردیس کشاورزی ومنابع طبیعی دانشگاه تهران
2 استاد پردیس کشاورزی ومنابع طبیعی دانشگاه تهران
عنوان مقاله [English]
In order to study the residue of diazinon in sour grape under filed conditions, an experiment was conducted during spring and summer 2011. The farm experiments were conducted at Khorassan Razavi Research Station (Mashhad). Diazinon was applied to a local variety of the vine called Keshmeshi Ghoochan at two time intervals (23 days apart from each other) with two doses: recommended dose (0.9 g a.i.L-1) and double dose (1.8 g a.i.L-1). The farm experiment was conducted as based on RCBD of three replications. Sampling was done at 0, 1, 2, 5, 8 and 12 days following the second spray (sour grape stage). Extraction and clean-up procedures were done as based on solid phase extraction. Quantification analysis of the residues was carried out using gas chromatograph apparatus equipped with nitrogen-phosphorus detector. Results revealed that most of the diazinon was dissipated (under environmental conditions) within the early days of spraying, with its half-life for the recommended and double doses being 1.5 and 1.21 days respectively. The dissipation rate of diazinon in the double dose application occurred faster as compared with the recommended dose and no significant difference was observed between the application rates within the last days. Samples taken before the second spray showed no diazinon residues, meaning that all the pesticide had dissipated within the 23-day period following the first spraying operation.