金线莲栽培中多菌灵残留动态及安全使用标准研究

Residue decline dynamics and safety utilization of carbendazim in cultivation of Anoectochilus roxburghii

采用甲醇提取，液液分配净化，高效液相色谱分析多菌灵在金线莲根、茎、叶及栽培基质中的残留消解动态，并对其安全使用标准进行讨论。结果表明不同多菌灵添加浓度下的回收率为82．9％-95．7％，RSD为2．0％-6．3％，满足农药残留检测要求。田间试验分别采用推荐剂量（1．0kg·hm^-2）和1．5倍推荐剂量（1．5kg·hm^-2）进行处理，2年连续实验结果表明，多菌灵在金线莲栽培基质中的半衰期为7．01～8．51d，在根中残留趋势为先升后降，半衰期为4．93～5．71d，在茎和叶中的消解半衰期分别为3．58。4．27，3．50—3．91d。若多菌灵在金线莲植株中的最高残留限量推荐值为0．5mg·kg^-1，每年以1．0kg·hm^-2的剂量喷施4次，最后一次施药和收获时间的安全间隔期可推荐为28d。

The paper aimed to study the residue decline dynamic and standards for safety utilization of carbendazim in roots, stems, leaves of Anoectochilus roxburghii and in growth media. Samples extracted with methanol were purified by liquid-liquid extraction and analysed by HPLC. The results showed that average rate of recovery was 82. 9% -95. 7% and RSD were 2. 0% -6. 3% with add of carbendazim in respectively diverse concentration, which meets inspection requirement of pesticide residue. Two kinds of dosages of carbendazim were treated, varying from recommended dosage （ 1.0 kg ·hm^ -2 ） to 1.5 times recommended dosage （ 1.5 kg · hm^-2）. Results of two years test showed that the half-life period of carbendazim were 7. 01-8. 51 d in the growth media ofA. roxburghii, 3.58- 4. 27 d in stems and 3.50-3.91 d in leaves, 4.93-5.71 d in roots. Providing max recommended residue of carbendazim in the cultivation ofA. roxburghii is 0. 5 mg· kg^-1 , sprayed 4 times a year with the dosage of 1.0 kg · hm^-2, 28 days is proposed for the safety interval of the last pesticide application＇s and harvest＇s date.