摘要
为筛选农业生产中防治草地贪夜蛾幼虫效果较好的杀虫剂,以草地贪夜蛾初孵幼虫和3龄幼虫作为试材,采用浸叶法,研究了8种杀虫剂对草地贪夜蛾幼虫的室内杀虫活性和毒力测定。结果表明:8种杀虫剂对草地贪夜蛾初孵幼虫在田间推荐最低剂量下药后72 h、对3龄幼虫在田间推荐最高剂量下药后96 h的校正死亡率均为100%,都具有很好的杀虫活性;在室内毒力测定中,10%多杀霉素甲维盐WG和5%甲氨基阿维菌素苯甲酸盐WG对草地贪夜蛾初孵幼虫药后24 h和48 h的LC50值分别为0.010 8 mg/L和0.010 9 mg/L,以及0.009 1 mg/L和0.007 7 mg/L,相对毒力较高;5%甲氨基阿维菌素苯甲酸盐WG对3龄幼虫药后24 h和48 h的LC50值分别为0.024 6 mg/L和0.017 9 mg/L,相对毒力最高;8种杀虫剂对草地贪夜蛾初孵幼虫和3龄幼虫均表现为同一杀虫剂对初孵幼虫的LC50值小于处理相同时间下对3龄幼虫的LC50值,且同一杀虫剂处理48 h的LC50值小于处理24 h的LC50值;室内杀虫活性和毒力测定均表明草地贪夜蛾初孵幼虫对药剂的抵抗能力弱于3龄幼虫。草地贪夜蛾初孵幼虫对药剂的抵抗能力明显弱于3龄幼虫,推荐在幼虫监测早期用药,5%甲氨基阿维菌素苯甲酸盐WG和10%多杀霉素甲维盐WG的LC50值较低,相对毒力较高,适合作为草地贪夜蛾虫口密度较大或暴发时用药,其他6种药剂在虫口密度较小时可作推荐药剂。
In order to screen the effective insecticides for the control of the larvae of the fall armyworm Spodoptera frugiperda,the indoor insecticidal activity and toxicity of eight insecticides against the larvae of the fall armyworm S.frugiperda were determined by leaf dipping method using the newly hatched and 3rd instar larvae of the fall armyworm S.frugiperda as the test materials.The results showed:the corrected mortality rates of the eight insecticides were 100%against the newly hatched larvae of the fall armyworm S.frugiperda at 72 h after the lowest recommended in the field dose and 96 h after the 3rd instar larvae at the highest recommended in the field dose,and all of them had good insecticidal activity.In the indoor toxicity assay,10%Spinosad emamectin benzoate WG and 5%Emamectin benzoate WG were more toxic to the newly hatched larvae of the fall armyworm S.frugiperda,with LCso values of 0.0108 mg/L and 0.0109 mg/L,and 0.0091 mg/L and 0.0077 mg/L at 24 h and 48 h after treatment,respec-tively.The highest relative toxicity of 5%Emamectin benzoate WG was observed against 3rd instar lar-vae,with LCso values of 0.0246 mg/L and 0.0179 mg/L at 24 h and 48 h after treatment,respectively.The LCso values of all eight insecticides for the newly hatched larvae and 3rd instar larvae of fall armyworm S.frugiperda showed that the LCso values of the same insecticide for newly hatched larvae were less than the LCso values of 3rd instar larvae treated at the same time,and the LCso value of the same insec-ticide treated for 48 h was smaller than that of the treatment for 24 h;the indoor insecticidal activity and toxicity determination showed that the newly hatched larvae of the fall armyworm S.frugiperda had a weaker resistance to the insecticides than the 3rd instar larvae.The resistance of the newly hatched lar-vae to the insecticides was significantly weaker than that of the 3rd instar larvae,recommended for use in the early stages of larvae monitoring.the lower LCso values and higher relative virulence of 5%E-mamectin benzoate WG and 10%Spinosad emamectin benzoate WG,which were suitable for use when the population density of the fall armyworm S.frugiperda was high or when there were outbreaks,and the other 6 insecticides could be used as the recommended insecticides when the population density was low.
作者
刘海强
贾龙
杜伟
陆占军
李宗泽
胡诗瑶
Liu Haiqiang;Jia Long;Du Wei;Lu Zhanjun;Li Zongze;Hu Shiyao(College of Agriculture,Ningxia University,Yinchuan 750021,China;General Agricultural Technology Extension Station,Ningxia Hui Autonomous Region;Yinchuan Customs Distict)
出处
《植物检疫》
2024年第1期64-71,共8页
Plant Quarantine
基金
宁夏回族自治区重点研发计划项目资助(2022BBF02027)。
关键词
草地贪夜蛾
杀虫剂
室内杀虫活性
毒力测定
Spodoptera frugiperda
insecticide
indoor insecticidal activity
toxicity determination
