为提升杀虫剂防效,减少杀虫剂用量,提高农产品安全,本研究采用虫体浸渍法研究了阳离子助剂1227和C8-10及有机硅助剂Breakthru S240对高效氯氰菊酯、毒死蜱和溴虫腈在甜菜夜蛾Spodoptera exigua幼虫和棉铃虫Helicoverpa armigera幼虫上的增效作用,并测定了3种助剂对清水物理性状的影响。结果表明:(1)供试助剂在两试虫上对3种杀虫剂均有显著增效作用,且增效比与助剂浓度存在显著相关关系。相同浓度下,除Breakthru S240对毒死蜱在棉铃虫上增效作用高于1227外,3种助剂在两试虫上对3种杀虫剂增效作用均为C8-10〉1227〉BreakthruS240。3种助剂在甜菜夜蛾上对3种杀虫剂的最佳增效浓度均为900mg/L。3种助剂在棉铃虫上对3种杀虫剂的最佳增效浓度分别为900,300和900mg/L。(2)3种助剂对清水物理性状均有显著影响。相同浓度下,供试助剂对清水表面张力的降低能力、对扩展直径和最大稳定持留量的增强能力均为Breakthru S240〉1227〉C8-10。综上所述,阳离子助剂1227和C8-10对3种杀虫剂在两试虫上的增效作用显著高于有机硅助剂Breakthru S240,但后者对于提高杀虫剂在叶表沉积量的能力高于前者,研究结果为3种助剂在杀虫剂领域的应用提供了一定的依据。
In order to increase the control effects,reduce the use of insecticides,enhance the safety of agricultural products,the synergism of two cationic adjuvants(1277 and C8-10) and one silicone adjuvant(Breakthru S240) to three insecticides beta-cypermethrin,chlorpyrifos and chlorfenapyr against 3rd-instar larvae of the Spodoptera exigua(Hübner) and Helicoverpa armigera(Hübner) were studied by dipping method,and the influence of the three adjuvants on physical properties of water was determined.The results showed that:(1) all of the tested adjuvants showed significant synergism to those insecticides,and the synergism ratio was significantly correlated to the concentration of adjuvant.The synergism ability of tested adjuvants to those insecticides against S.exigua and H.armigera was C8-101227Breakthru S240 under the same concentration,except that Breakthru S240 showed higher synergism ability to 1227 against H.armigera.The optimum synergistic concentration of tested adjuvants to those insecticides against S.exigua was 900 mg/L,while against H.armigera it changed into 900 mg/L(1227) ,300 mg/L(C8-10) and 900 mg/L(Breakthru S240) ,respectively.(2) All of the tested adjuvants showed significant influence on the physical properties of water.Reducing ability of surface tension,as well as the increasing ability of expanded diameter and the maximum retention of tested adjuvants to water were Breakthru S2401227C8-10 under the same concentration.In conclusion,the synergism of tested cationic adjuvants(1277 and C8-10) to three insecticides against both S.exigua and H.armigera was significantly higher than that of silicone adjuvant(Breakthru S240) ,while the latter showed better ability to enhance insecticide deposition on plant leaves than the former.These results provide theoretical proofs for the application of the tested adjuvants.