| 摘要: |
| 【目的】明确5%去甲斑蝥素微乳剂对小菜蛾的田间防治效果。【方法】采用浸叶法，测定了5%去甲斑蝥素微乳剂对小菜蛾的室内毒力；选用不同剂量5%去甲斑蝥素微乳剂和不同施药时期进行田间防治试验，观察该药剂对小菜蛾的田间防治效果。【结果】5%去甲斑蝥素微乳剂对小菜蛾3龄幼虫具有较高毒力，24 h的致死中浓度（LC50）为85.10 mg/L。在田间施用剂量为111.11～138.89 g/hm2时，5%去甲斑蝥素微乳剂对小菜蛾药后7 d的防效可达90%以上；进一步用111.11 g/hm2 5%去甲斑蝥素微乳剂在小菜蛾不同龄期施药，结果表明，在1龄幼虫盛发期施药药效最好，7 d后对小菜蛾的防效可达90.96%。【结论】5%去甲斑蝥素微乳剂在室内和田间对小菜蛾均具有很好的控制效果，具有防效高、持效时间长和安全等优点，有产业化开发前景。建议在甘蓝处于包心初期施用5%去甲斑蝥素微乳剂，施用剂量以111.11 g/hm2为宜。 |
| 关键词: 5%去甲斑蝥素微乳剂 小菜蛾 防效 杀虫活性 |
| DOI： |
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| 基金项目:国家公益性行业（农业）科研专项（200903052）；陕西省“13115”科技创新工程重大科技专项（2007ZDKG-14） |
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| Application of 5% norcantharidin microemulsion against Plutella xylostella |
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WANG Zhi-jun,ZHANG Ya-lin,HUANG Min
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| Abstract: |
| 【Objective】The field control of Plutella xylostella using 5% norcantharidin microemulsion (ME) was investigated.【Method】In laboratory,toxicity of 5% norcantharidin ME against P.xylostella was measured using leaf-dipping method.5% norcantharidin ME with different doses were sprayed at different periods in field to confirm its control efficacy against P.xylostella.【Result】In laboratory tests,5% norcantharidin ME had high toxicity to P.xylostella with LC50 after 24 h of 85.10 mg/L.Applying 111.11-138.89 g/hm2 5% norcantharidin ME in field obtained 90% control efficacy against P.xylostella 7 d after treatment.Spraying 5% norcantharidin ME with dose of 111.11 g/hm2 against P.xylostella with different ages showed that the optimum application time was the outbreak period of the first instar with the efficacy of 90.96% 7 d after treatment.【Conclusion】5% norcantharidin ME had high control effect against P.xylostella,with high persistence and safety,and was suitable for industrialization.Application of 111.11 g/hm2 to cabbage at the head forming stage was suggested. |
| Key words: 5% norcantharidin ME Plutella xylostella efficacy application |
