The Residues Of Trifloxy Strobin In Chilli Field And Its Adsorption-desorption On Soil

In order to study the residues dissipation and ecological environment effects that trifloxystrobin being used in chilli and soil and to determine its ecological behavior and safety, to guide its scientific and rational use, the spiked recovery experiment method was established. And on this basis,30% trifloxystrobin SC was applied in chilli and soil. Then put forward the science suggestions of the use of 30% trifloxystrobin suspending agent (SC) in chilli and soil. In addition, the adsorption/desorption of trifloxystrobin and its main factors in six kinds of soil were studied. Moreover, the effects of low molecular weight organic acids (LMWOA) on the adsorption/desorption of trifloxystrobin in soil were also investigated. The main conclusions in this paper were as follows:(1) The study of recovery test was operated with GC-ECD technology, and the analysis and detection methods of trifloxystrobin in chilli and soil samples were also conducted. Afterward, the field experiment was applied in researching the degradation dynamics of trifloxystrobin in chilli and soil. The results indicated that when fortified level ranged from 0.03 to 1.00mg/kg, the recovery rates of trifloxystrobin in chilli and soil were 89.9% to 101.8% and 93% to 104.9%, respectively. In addition, the relative standard deviation (RSD) ranged from 2.3% to 5.1% in chilli and 1.1% to 2.7% in soil, the results in this study can meet the requirements of pesticide residues analysis method.(2) The half-life of trifloxystrobin, in chilli of Changsha, Qingdao and Hangzhou was 4.95 d to 16.23 d, and that in soil was 5.63 d to 17.37 d. All the above values were less than 30 days. To sum up, trifloxystrobin should be classified as an easily degradable agrochemical in chilli and soil.(3) The highest recommendation dose of 30% trifloxystrobin SC is 168.75g a.i./ha, The applying pesticide times are 3, the spray interval is 7 d and the security clearances is 7 d.(4) The adsorption/desorption equilibrium time of trifloxystrobin in 6 kinds of the tested soil are 24 h. Since their adsorption/desorption isotherm can be a very good conforms to the Linear equation and Freundlich equation and the correlation coefficient had also reached significant level, this kind of adsorption belongs to the physical adsorption.(5) The effects of LMWOA on the the adsorption/desorption amount of trifloxystrobin in the soils are remarkable. In the adsorption behavior, the ability to promote adsorption is: citric acid> oxalic acid> acetic acid. In the act of desorption, the ability to promote is: acetic acid> oxalic acid> citric acid.