5%氟铃脲乳油在棉田生态系统中的安全使用评价  

Application Safety Assessment of Hexaflumuron EC in Cotton Field Ecosystem

作　　者：郭正元[1] 杨仁斌[1] 徐珍[1] 黄帆[1] 

机构地区：[1]湖南农业大学农业环境保护研究所,湖南长沙410128

出　　处：《农业环境科学学报》2007年第6期2329-2333,共5页Journal of Agro-Environment Science

基　　金：国家农业部药检所资助项目

摘　　要：利用HPLC建立了棉田生态系统中氟铃脲的残留行为、消解动态,及其对棉田土壤中脲酶和过氧化氢酶的影响,为其环境和生态安全提供重要的科学依据。结果表明:(1)土壤和棉籽样品中的氟铃脲残留物用甲醇提取,而棉叶样品中的氟铃脲用二氯甲烷提取,土壤样品和棉叶样品均过弗罗里硅土柱用乙酸乙酯淋洗。棉籽样品过弗罗里硅土柱采用乙酸乙酯和丙酮混合淋洗液,浓缩后用高效液相色谱仪(带UVD)进行检测;当添加浓度为0.022、0.050、0.504mg·kg-1时,添加回收率为80.05%～105.16%,变异系数为1.17%～7.98%,最小检出量为2.36×10-9g。(2)氟铃脲在棉叶和土壤中的半衰期分别为长沙4.19和7.73d,天津9.76和7.99d,符合一级动力学方程;氟铃脲在使用剂量下,有效成分在棉籽中的残留量为LOD,保证了棉籽使用的安全性。(3)氟铃脲对各浓度处理的土壤脲酶活性均产生了一定的影响,施药初期,各浓度处理的土壤脲酶活性均被抑制,且浓度越高,抑制作用越明显。之后0.504mg·kg-1处理的土壤脲酶活性逐渐恢复到和对照相一致,5.040mg·kg-1处理的土壤脲酶活性则从第6d起一直处于被激活状态,而10.080mg·kg-1处理的土壤脲酶活性则在整个培养期间一直处于被抑制状态。(4)从施药后第1d到第14d,低浓度(0.504和5.040mg·kg-1)氟铃脲处理的土壤多酚氧化酶的活性被激活,之后逐渐恢复到和对照一致。而高浓度处理(10.080mg·kg-1)的土壤多酚氧化酶活性,从施药后第1d到第14d一直处于被抑制状态,从第14d开始一直到培养结束均处于被激活的状态。(5)氟铃脲0.504和5.040mg·kg-1处理均不会对土壤脲酶和多酚氧化酶造成不利影响,根据试验氟铃脲在长沙和天津两地的土壤原始附着量分别为0.541和0.653mg·kg-1,按氟铃脲的使用剂量施药,对土壤生态系统影响很小。A HPLC method was used to evaluate the degradation behavior and environmental security of Hexaflumuron EC, in cotton field ecological system. The results were as follows： （1） The half-lives of hexaflumuron in cotton leaves and soil were 4.19 d and 7.73 d in Changsha, while 9.76 d and 7.992 d in Tinajin. （2） When Hexaflumuron EC was applied at recommended dose, the residues in cotton seeds were LOD, which ensured edible safety of cotton seeds. （3） 10.080 mg·kg^-1 of hexaflumuron displayed inhibition effect on the activity of urease in cotton field during the incubation period, 5.040 mg·kg^-1 of hexaflumuron inhibited at first then stimulated, while 0.504 mg·kg^-1 hexaflumuron stimulated first then went back to CK. （4） The effects of hexaflumuron on polyphendoxidase activity was complicated, in general, at low concentration of Hexaflumuron EC, the polyphendoxidase activity was inhibited until 14 days, then tended to be consistent with that of CK, but it was inhibited from the first to the 14th day, stimulated from the 14th day to 28th day at high concentrations of Hexaflumuron EC.

关 键 词：氟铃脲 农药残留 消解 脲酶 多酚氧化酶 

分 类 号：X592[环境科学与工程—环境工程]