定虫脲(Chlorfluazuron)对粘虫幼虫(Mythimna separata L.)杀虫作用的研究

定虫脲(CFU)系苯酰基苯脲类系列药剂中有较高药效的一个品种,它对三龄粘虫幼虫的毒效作用较其第一代杀虫剂除出脲(Diflubenzuron)高约70倍,对六龄粘虫幼虫,用点滴、胃毒和注射方法处理,最终毒效相若。根据粘虫六龄幼虫表皮几丁质含量的动态变化,在不同时龄时用点滴法施药,发现试虫的死亡时间和受药时间有明显相关。以72时龄为界,在此以前受药者试虫多数不能变态,死亡于化蛹之前。而72时龄以后施药者,试虫则多数可变态,但在蛹期陆续死亡。因此,72时龄是表皮几丁质沉积的分界线,但并未发现施药后的原位反应(insi-tu)或几丁质厚度和药效之问的相关。

Studies On The Mode Of Action Of Chlorflubenzuron In Oriental Army worm Larvae(Mythimna separate)

Through measuring the content of culicle chitin and among the chilin dynamic change for application chlorflubenzuron it was found that between the mode of action of chlorflubenzuron and chilin synthase there were no direct relations but the reaction of the toxicity symptom just accordance with the dynamic of ecdysteroil titre. Therefore, applying chlorflubenzuron in early stadium of 6th larvae the effectiveness was related to inhibition of the commitment peak of ecdysone, application in 72 hours, after molting most part of test invests accomlished the developmental sequence due to no interference commitment peak. Therefore benzoyphcenye urea was the hormone interfering agents rather than chilin synthesis agents.