【作者】 贾劲松；

【导师】 柏连阳； 任新国； 王跃龙；

【作者基本信息】 湖南农业大学 ， 农药学， 2004， 硕士

【摘要】 随着农药的大量使用，农药在保障农业生产的同时也给环境带来了不容忽视的负面影响。“高效、低毒、低残留”已成为未来农药发展的必然趋势。因此，开发一类既能提高其生物活性又能降低其环境残留的农药品种一直是广大农药研究工作者的重要课题。 本文以光降解源纳米材料TiO₂的制备方法、表征、光催化活性及其改性和吸附行为的研究为基础，确定了纳米TiO₂与甲基嘧啶磷、溴虫腈两种不同农药的复合技术：表面活性剂包裹法制备10％溴虫腈纳米制剂和采用原位技术制备5％甲基嘧啶磷纳米制剂。并对复合形成的两种纳米农药制剂作了进一步的光降解性研究及生物活性评价。还对10％溴虫腈纳米制剂在甘蓝和土壤中的残留作了探讨。 研究结果表明，纳米TiO₂的加入能明显提高农药制剂的光降解性：其中10％溴虫腈纳米制剂比10％溴虫腈悬浮剂在紫外灯下照射1h、3h、5h、22.5h的降解率分别高出12.9％、23.1％、32.6％、65.0％；5％甲基嘧啶磷纳米制剂比没加纳米TiO₂的5％甲基嘧啶磷对照样在紫外灯下照射1h、2h、4h的降解率分别高出14.2％、17.2％、11.1％。 纳米农药制剂能明显提高农药的生物活性，室内毒力测定结果表明：10％溴虫腈纳米制剂的毒力是95％溴虫腈原药毒力的1.68倍、5％甲基嘧啶磷纳米制剂的毒力是90％甲基嘧啶磷原药毒力的1.32倍；田间药效试验结果表明：10％溴虫腈纳米制剂防治甘蓝斜纹夜蛾的田间防效优于20％溴虫腈乳油，药后1天和药后3天的校正防效分别高出4.89％和3.05％；5％甲基嘧啶磷纳米制剂防治水稻二化螟的田间防效比同等剂量的20％甲基嘧啶磷乳油高出16.4％，保苗效果高出18.4％。 纳米农药制剂还能有效降低农药在作物和土壤中的残留，残留消解试验结果表明，澳虫腊在土壤中的半衰期分别为:10%澳虫睛纳米制剂4.38天，10%澳虫睛悬浮剂10.71天;澳虫睛在甘蓝中的半衰期分别为:10%澳虫睛纳米制剂1.50天，10%澳虫腊悬浮剂3.86天。最终残留试验结果表明，10%澳虫腊纳米制剂在土壤中的残留情况为:其高低浓度处理，施药二次、三次的药后3天、7天残留量均未检出，含量<0.012m叭g;其在甘蓝中的残留情况为:药后3天的残留量明显高于药后7天，低浓度药后3天在<0.02一0.033m叭g水平，高浓度药后3天在<0.02一0.122m叭g水平，而药后7天残留量在<0.02一0.047m眺g水平。 本研究表明，纳米农药制剂是一类极具开发潜力、符合未来农药发展方向的优良制剂，具有较好的应用开发前景，可产生明显的经济效益、社会效益和环境效益。更多还原

【Abstract】 While the wide use of pesticide ensures the agricultural production, the immense negative effect it brings to the environment cannot be ignored. "High-efficiency, low-noxious, low-residue" has been a natural trend for the development of future pesticide. Therefore, it is an -important task for pesticide researchers to exploit a kind of pesticide which can both improve biological activities and reduce residue.Based on the study of the preparation method, characterization, photocatalysis, modifcation and adsorption of photocatalytic degradative nano-TiO2, this thesis confirmed the composite methods of the two different kinds of pesticide, nano-TiO2 and chlorfenapyr and pirimiphos-methyl. And it studied the photocatalytic degradation and biological activities of the two kinds of nano-pesticides. It also conducted an exploratory study on the residue of nano-chlorfenapyr in cabbage and soil.The results demonstrated that the adding of nano-TiO2 could obviously improve photocatalytic degradation. The photocatalytic degradation rate of 10% nano-chlorfenapyr which is irradiated in unltra-violet lamp for 1hr, 3hrs, 5hrs and 22.5hrs is 12.9%, 23.1%, 32.6% and 65.0% higher than 10% chlorfenapyr SC respectively. The photocatalytic degradation rate of 5% nano-pirimiphos-methyl irradiated in unltra-violet lamp for Ihr, 2hrs and 4hrs is 14.2%, 17.2% and 11.1% higher than 5% pirimiphos-methyl CK respectively.The nano-pesticides can obviously improve the biological activities of pesticide. The results of the indoor bioassay test showed that the virulence of 10%nano-chlorfenapyr is 1.68 times stronger than that of 95% chlorfenapyr TC and the virulence of 5% nano-pirimiphos-methyl is 1.32 times stronger than that of 90% pirimiphos-methyl TC. The results of the field test showed that the field effect of 10% nano- chlorfenapyr to spodoptera litura on cabbage is 20% superior to that of chlorfenapyr EC and the Id and 3d corrected controlling ratios are 4.89% and 3.05% higher respectively. The effect of field of 5% nano-pirimiphos-methyl to Chilo suppressallis Walker on rice is 16.4% higher than that of 20% pirimiphos-methyl EC and the protection effect upon seedlings is 18.4% better.In addition, the nano-pesticides can also efficiently reduce the residue of pesticide in crops and soil. The result of residue and dissipation of chlorfenapyr showed that the half-life of 10% nano-chlorfenapyr in soil is 4.38 days and that of 10% chlorfenapyr SC in soil is 10.71 days; the half-life of 10% nano-chlorfenapyr in cabbage is 1.50 days and that of 10% chlorfenapyr SC in cabbage is 3.86 days. The results of ultimate residue test of chlorfenapyr showed that the residue amount of 10% nano-chlorfenapyr in the soil which is treated with high and low rate 3 days and 7 days after 2 and 3 treatments has not been detected and is lower than 0.012mg/kg. The amount of residue which is detected in cabbage after 3 days is obviously higher than that after 7 days. The amount of residue after 3 days in the low-rate-treated cabbage is less than 0.02-0.033mg/kg and that in the high-rate-treated cabbage is less than 0.02-0.122mg/kg. But the amount of residue after 7days is less than 0.02-0.047mg/kg.The results of the research showed that the nano-pesticides formulation is a kind of promising pesticide formulation which conforms to the developing trend of future pesticide, will have a bright application prospect and bring obvious economic benefit, social benefit and environmental benefit.更多还原