关键词: 烯酰吗啉, 马铃薯, 土壤, 消解动态, 农药残留

Abstract: Dimethomorph is a new kind of therapeutic special fungicide, widely used in disease prevention and control of late blight. In order to reasonably apply dimethomorph in the prevention and treatment of potato late blight, this experiment used the method of UPLC-MS to study the dissolution dynamics and final residues of dimethomorph in potato tubers, plants and soil from different places (Ningxia Hui Autonomous Region and Heilongjiang Province) in different years (2015 and 2016). The results showed that the half-lives of dimethomorph in potato plants were 22.36 d (Ningxia) and 12.38 d (Heilongjiang) in 2015, 3.69 d (Ningxia) and 28.88 d (Heilongjiang) in 2016. The half-lives of dimethomorph in soil were 231.05 d (Ningxia) and 6.48 d (Heilongjiang) in 2015, 69.31 d (Ningxia) and 13.33 d (Heilongjiang) in 2016. The final residues of dimethomorph in potato plants, tubers and soil were different with different dosages, times and time intervals. When the dosage was 1 345.5~2 018.2 g (a.i)/hm2, the spraying times was 3~4, the interval of application was 7 days, and the residue of enylmorpholine in potato tubers was all less than 0.02 mg/kg, which was lower than the maximum residue limit of 0.05 mg/kg set in China.

Key words: dimethomorph, potato, soil, degradation dynamics, pesticide residue