高效氯氟氰菊酯对小白菜保护酶活性及脂质过氧化作用的影响

Effects of Lambda-cyhalothrin Stress on Activites of Cell Defense Enzymes and Lipid Peroxidation in Brassica chinensis Seedlings

为了解拟除虫菊酯类农药胁迫对蔬菜生理生化过程的影响,采用田间试验方法研究了不同浓度2.5%高效氯氟氰菊酯水乳剂对小白菜中超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性和丙二醛(MDA)含量的影响。结果表明,喷施推荐用量(有效成分含量为1.25 mg/L)及加倍用量(有效成分含量为2.5 mg/L)的高效氯氟氰菊酯后,小白菜SOD活性明显增强,至第7天时接近或低于对照;POD活性在喷药后逐渐升高;CAT活性在喷施推荐用量药剂后表现为先增高再降低,但均明显高于对照,喷施加倍用量药剂1～3 d后,CAT活性显著高于对照,药后5～7 d则明显低于对照。喷施加倍用量药剂后小白菜叶片中MDA含量均明显高于对照;推荐用量药剂处理后,MDA含量在药后1～5 d变明显升高,至第7天时恢复正常。

To better understand antioxidative defense responses of vegetables to the pyrethroid pesticide,the activity of several antioxidant enzymes such as superoxide dismutase （SOD）,peroxidase （POD）,catalase （CAT） and the content of malondialdehyde （MDA） were cxamined in Brassica chinensis seedings sprayed with different concentrations of lambda-cyhalothrin in the field.The results showed that the SOD activity increased significantly both at low concenration （a.i.1.25 ng/L） and high concentration （a.i.2.5 mg/L）,but was close to or lower than that of the control at 7 d after spray.In addition,The POD activity increased linearly with increasing concentration of lambda-cyhalothrin and with exposure time as well.The CAT activity increased first and reduced later at 1.25 mg/L,but higher than that of the control.Moerover,the CAT activity was higher during 1-3 d and lower during 5-7 d than that of the control at 2.5 mg/L.The MDA content significantly increased at higher concentration compared with that of the control,and it was higher than that of the control at low concentration duing 1-5 d.