杀虫剂对蠊卵啮小蜂的毒性研究

Toxicity of insecticides to Tetrastichus hagenowii

目的了解常用杀虫剂对蠊卵啮小蜂的毒性，为蟑螂的化学防制与生物防制提供科学依据。方法药膜法和浸渍法。结果供试的杀虫剂均对蠊卵啮小峰成蜂具有很强的触杀毒性，能在短时间内击倒并致死试虫。在使用剂量下，7种杀虫剂的触杀毒性顺序为：敌敌畏〉列喜镇≌拜力坦〉毒死蜱〉奋斗呐〉除敌〉拜虫杀。对成蜂的滞留毒效敌敌畏可维持5～7d、毒死蜱120—130d、残杀威180～200d、拟除虫菊酯类药物则可达7个月以上。敌敌畏、列喜镇、拜力坦和毒死蜱等乳油类药剂对蠊卵啮小峰未成熟期的生长发育影响甚大，能致死未成熟体，使其不能羽化；而悬浮剂型的拟除虫菊酯类药剂对未成熟体的生长发育影响较轻，大部分都能发育至成体，并顺利羽化，但残留在寄主卵荚上的药物对羽化后的成蜂表现出很强的滞留毒效。结论蠊卵啮小峰对化学杀虫剂高度敏感，因此，在蟑螂防制工作中必须要坚持综合防制，尤其要协调好化学防制与生物防制之间的关系，选择适当的药物、剂型和施药技术，因时、因地制宜地用药，以充分发挥天敌的自然控制作用，巩固灭效。

Objective To realize the toxicity of insecticides on Tetrastichus hagenowii, and offer the basis of biological and chemical control for cockroach. Methods Drug-membrane method and dipping method. Results The insecticides used in the experiment showed strong contact killing toxicity to the adults of T. hagenowii which could be knocked down in a short time. In the application dosage, the contact toxicity order of 7 kinds of insecticides to the adults was DDVP 〉 Resigen≌Blattanex 〉 Chlorpyriphos 〉 Fendona 〉 Crackdown 〉 Responsar. The preserving toxicity to the adults of T. hagenowi lasted for 5 to 7 days by DDVP, 120 to 130 days by Chlorpyriphos,180 to 200 days by Propoxur, more than seven months by synthetic pyrethroid. Emulsifiable concentrate of DDVP, Resigen, Blattanex and Chlorpyriphos markedly influenced growth and development of the immature stage of T. hagenowii, which had been killed and could not emerged. Suspension concentrate of synthetic pyrethroid influenced more slightly on the immature development of Tetrastichus hagenowii. Most of immature could emerge to adult stage. The insecticides residual in the ootheca showed strong preserving toxicity to the emerging adults. Conclusion Due to the high sensitivity of Tetrastichus hagenowii to insecticides, the integrated control measures should be adopted. Especially coordination between chemistry and biologic control measures, the suitable selection of pesticide, dosage form and method, the application of insecticides corresponding to condition and time should be considered, which would help natural enemy or predators to play a good natural control effect.