黄帚橐吾乙醇提取物对黏虫毒力及其解毒酶系活性的影响

Effect of Ethanol Extract from Ligularia virgaurea on Toxicity and Activity of Detoxifying Enzymes of Mythimna separata

黏虫(Mythimna separata)是典型的杂食性迁飞性农业害虫,每年都给我国的农业生产造成极大的经济损失。测定黄帚橐吾(Ligularia virgaurea)乙醇提取物对黏虫幼虫的毒力,并从细胞色素P450(CYP450)、谷胱甘肽-S-转移酶(GST)、羧酸酯酶(CarE)、酸性磷酸酯酶(ACP)和碱性磷酸酯酶(ALP)等解毒酶系活性的角度研究黏虫幼虫对该药物的生理生化响应。结果表明,黄帚橐吾乙醇提取物对黏虫幼虫有较强的生物活性,LC_(50)为3.655 mg/mL;CYP450活性在前8 h略有上升,12 h后显著降低(P<0.05);GST活性在4 h时被显著激活,随后受到极显著抑制(P<0.01);3种酯酶活性整体表现出逐渐降低的趋势。上述酶活性变化表明CYP450和GST可能参与了黏虫对黄帚橐吾提取物的代谢过程,但其最终被显著抑制的结果提示黄帚橐吾源农药较难使黏虫产生抗药性,具备被开发成为新型生物农药的潜力。

Mythimna separata is a typical omnivorous migratory agricultural pest,which causes great economic losses to China s agricultural production every year.We determined the toxicity of ethanol extract of Ligularia virgaurea to M.separata larvae,and studied the physiological responses by measuring detoxifying enzyme activity such as cytochrome P450(CYP450),glutathione-S-transferase(GST),carboxylesterase(CarE),acid phosphatase(ACP)and alkaline phosphatase(ALP).The results showed that the ethanol extract from L.virgaurea had a strong bioactivity against M.separata larvae,with LC_(50)of 3.655 mg/mL.The activity of CYP450 increased slightly in the previous 8 hours and then decreased in the next 12 hours(P<0.05).The activity of GST was significantly activated at 4 hours and then significantly inhibited(P<0.01).And the activities of 3 kinds of esterase showed a trend of gradual decrease.All of these results indicated that CYP450 and GST may be involved in the metabolism,but the inhibition indicated that extract from L.virgaurea was difficult to induce resistance of M.separata larvae.Therefore,the extract from L.virgaurea had the potential to be developed as a new biopesticide.