虫酰肼对甜菜夜蛾生长发育的影响及抗性选育

 【目的】评估甜菜夜蛾对虫酰肼产生抗性的风险，了解虫酰肼3，5-二甲基苯甲酸1-1（1，1一二甲基乙基）-2（4-乙基苯甲酰）肼，tebufenozide]对甜菜夜蛾生物学特性的影响。【方法】采用浸渍法，分别使用虫酰肼对甜菜夜蛾3龄幼虫LC50剂量隔代和LC10剂量继代汰选抗性，比较各代生物学特性变化；不同剂量分别处理甜菜夜蛾3龄幼虫和卵块，研究药剂对当代及下一代的主要生物学特性的影响。【结果】LC50剂量隔代汰选抗药性至F11代，甜菜夜蛾幼虫对该药剂的敏感性未发生明显变化，表明没有产生抗性；羽化率及成虫寿命变化不明显，而化蛹率、蛹重和单雌产卵量逐代显著降低。用LC10剂量继代汰选抗性缓慢上升，至F19代抗性增加2.52倍；化蛹率、蛹重、羽化率、成虫寿命及单雌产卵量变化不显著。分别用虫酰肼2.5、5、10、20及40 µg?ml-1浸渍法处理3龄幼虫，随剂量提高幼虫成活率随之降低，幼虫期缩短，化蛹率及蛹重下降，但羽化率及成虫雌雄比变化不大；当大于等于10 µg?ml-1剂量处理幼虫，不仅随剂量提高而降低了下一代成虫产卵量，而且下一代幼虫成活率，幼虫及蛹体重也有所下降。用虫酰肼10～300 µg?ml-1剂量浸渍卵块，卵孵化率与对照无明显差异，但用 50 µg?ml-1以上剂量处理时，可明显降低初孵幼虫、4日龄幼虫成活率以及幼虫及蛹体重。【结论】虫酰肼对甜菜夜蛾当代及下一代的生物学特性存在明显影响，而甜菜夜蛾对该药剂不易产生抗药性。

Effects of Tebufenozide on the Biological Characteristics of Beet Armyworm(Spodoptera exigua Hübner)and Its Resistance Selection

【Objective】In this paper the resistance risk of Spodoptera exigua to tebufenozide and the biological characteristics of Spodoptera exigua treated with tebufenozide were studied.【Method】Using dipping method, selections for resistant population of spodoptera exigua to tebufenozide were carried out from laboratory strain by treating alternative generation’s 3rd-instar larvae at LC50 dose and treating every generation’s larvae with LC10 dose. The biological characters of each generation were determined. Dipping exposure of 3rd-instar larvae and egg mass of Spodoptera exigua with tebufenozide under different dose, the effects on biology characters in current generation and followed generation was also studied.【Result】Treated alternative generation’s larvae with LC50 dose, Spodoptera exigua had no loss in susceptibility to tebufenozide from F1, F3, F5, F7 ,F9 to F11. But as the selection procedure, the pupation rate, average pupa weight and eggs per female of corresponding followed generation were decreased. Another selection experiment of successive treating every generation’s larvae with LC10 dose of tebufenozide to F19 only obtained 3.52-fold resistance ratio to the initial laboratory strain of spodoptera exigua. The pupation rate, average pupa weight, eclosion rate, adult life and eggs per female had no significant changes in each generation. Dipping exposure of 3rd-instar larvae to tebufenozide solutions of 5-40µg?ml-1, the survival rate of larvae was decreased after three days, and the larval period time, pupation rate and the mean pupa weights were significantly shorter or lower than those of control larvae as the dose increasing. But the eclosion and female/male rate