80%克菌丹水分散粒剂在苹果和土壤中的残留及消解动态

通过2年3地动态消解及最终残留试验,研究80%克菌丹水分散粒剂在苹果及土壤中的降解情况,并通过气相色谱法对苹果及土壤中克菌丹残留量进行测定。结果表明,动态试验中克菌丹在苹果和土壤中降解速率较快,均符合一级动力学方程,克菌丹在苹果和土壤中降解的半衰期分别为7.3~12.6 d、9.8~17.8 d,且动态及终残试验中克菌丹残留量均低于最大残留限量15 mg/kg。在苹果种植中,其推荐剂量为800倍稀释液(有效成分4 000 mg/kg),最多施药3次。

Degradation Dynamics and Residues of Captan 80% WG in Apple and Soil

The dynamic degradation and final residues were tested in 3 sites during 2 years,to study the degradation of captan 80% WG in apple and soil. The captan residues in apple and soil were determined by GC. The results showed that the degradation rate of captan in apple and soil in the dynamic tests was fast,and all accorded with the first-order dynamics e-quation. The half-lives of captan in apples and soil were 7.3~12.6 d and 9.8~17.8 d respectively,the final captan residues were all less than the maximum residue limit of 15 mg/kg. In apple planting, it should be safe and reliable to apply captan (80% WG,800×,a. i. 4000 mg/kg) with the recommended dose 3 times at most.