不同剂型阿维菌素理化性能及对小菜蛾活性的评价

研制了阿维菌素微乳剂和水乳剂配方，并在室内和田间测定了阿维菌素不同剂型对小菜蛾幼虫的生物活性．结果表明：微乳剂和水乳剂的表面张力、渗透时间、润湿时间等测定值均优于乳油，微乳剂是其中表现最稳定的水性化剂型．毒力测定表明阿维菌素与杀虫双复配剂的增效比值最高．当对照剂型乳油LC50设为1时，其毒力比值达3．24．田间施药后，阿维菌素和杀虫双复配剂对小菜蛾的防效最好，药后7d防效达89．12％，均明显高于阿维菌素单剂，3个单剂处理间差异显著．

Study on Physical and Chemical Properties of Avermectin Preparations and Their Bioactivity to Plutella xylostella

Two types of water-based preparations of avermectin were developed and the bioactivity and control efficacy to diamondback moth,Plutella xylostella L.,in experiment were carried out.The results from the experiment are as follows: The physical and chemical properties such as surface tension,penetrability,wettability of microemulsion and emulsion in water of avermectin and dimehypo were better than those of emulsifiable concentrate(EC).Among the preparations microemulsion tested was the most stable and viable.The bioassay in laboratory indicated that synergistic ratios of compound preparation of avermectin and dimehypo were higher than those of EC and its synergistic ratio(SR) was 3.24 while LC_(50) value of EC was set as 1.0.Also,they showed significantly more effective than single preparation in plot field and the control efficacy was as high as 89.12% in 7 days after treatment,but no significantly different among single preparations.The water-based preparations of avermectin and dimehypo not only had better control efficacy,but also deferred developmental speed of resistance and reduced pollution of organic compounds in environments.