نوع مقاله : مقاله پژوهشی
عنوان مقاله English
نویسندگان English
The improper and excessive use of pesticides is harmful to the environment, particularly to water and soil quality and non-target organisms. It also increases pesticide residues in products beyond the Maximum Residue Limits (MRL). Nanoformulations with the property of controlled release by increasing the performance and reducing the consumption of poisons have reduced the negative effects of these compounds on the environment to negligible or low levels. For this purpose, in this study, monomers of glycerol (Gly), adipic acid (Ad), maleic acid anhydride (Ma), polyethylene glycol (PEG) 1000 and zinc oxide nanoparticles (ZnO) were used for the synthesis of dimethoate nanoformulations by polycondensation method. The dissipation kinetics of concentration and residue of four nanoformulations of dimethoate Gly-Ad-Ma/DiM (Nano-DiM I), Gly-Ad-Ma-ZnO/DiM (Nano-DiM I/ZnO), Gly-Ad-Ma-PEG/DiM (Nano-DiM II) and Gly- Ad-Ma-PEG-ZnO (Nano-DiM II/ZnO) were evaluated in the leaves and pods of soybean (Glycine max) with SFOK (Simple First-Order Kinetic) and FODED (First-Order Double-Exponential Decay) models under field conditions and compared with the commercial formulation of dimethoate. To conduct this research, "Ketol" soybean plant was done in the field near Gorgan (Kordkoi) in the form of a completely randomized block design with three replications in the middle of June 2019. At the beginning of flowering, when the populations of Thrips tabaci L. and Bemisia tabaci Genn, the treatments of different nanoformulations of dimethoate in the recommended concentration (7%) and traditional formulation (EC=40%) were uniformly sprayed onto the soybean plants. After extracting dimethoate residues with HPLC and quantifying them, the data were fitted with two (SFOK) and (FODED) models. The high sensitivity of the analytical method and the efficiency of the extraction and purification steps were confirmed by considering the detection limit (0.03) and recovery percentage (89% and 92%) were determined. The results of analysis of variance showed that the data obtained were consistent with SFOK and FODED models and were significantly different (P<0.01). Statistical indices (DT50, DT90 and PHI) in nanoformulations (Nano-DiM I) and (Nano-DiM I/ZnO) by fitting the FODED model, respectively (0.43, 1.46 and 14 days) and (0.33, 1.10 and 7 days) respectively. Statistical indices in nanoformulations (Nano-DiM II) and (Nano-DiM II/ZnO) were obtained by fitting the SFOK model (0.42, 1.42 and 7 days) and (0.33, 1.11 and 7 days), and in the case of commercial dimethoate by fitting both models (1.91, 6.38, and 14 days) were estimated. The results showed that the residual dimethoate in synthetic nanoformulations dissipated rapidly in soybean leaves and pods. Therefore, the use of these nano-pesticides is suggested due to low use of pesticide and rapid decomposition of residues. In addition, the biodegradable nature of these nanoformulations and better efficiency suggest that they could be introduced as environmentally friendly pesticides into the environment.
کلیدواژهها English
