两种昆虫生长调节剂对黑腹果蝇和斑翅果蝇的生物活性

为探讨昆虫生长调节剂氟铃脲和虱螨脲对黑腹果蝇Drosophila melanogaster和斑翅果蝇D.suzukii的毒性机制,采用室内生测法测定氟铃脲、虱螨脲对2种果蝇2龄幼虫的毒力,以及其在亚致死浓度LC_(10)、LC_(20)下对2种果蝇体内几丁质酶活性的影响。结果显示,经不同浓度的氟铃脲和虱螨脲处理后,随着时间的延长和浓度的增加,2种果蝇的死亡率均明显增加,氟铃脲处理可使2种果蝇的死亡率最高达到83.33%,明显高于虱螨脲处理后黑腹果蝇(65.00%)和斑翅果蝇(66.66%)的死亡率。亚致死浓度LC_(10)和LC_(20)的虱螨脲处理果蝇2龄幼虫24 h后,黑腹果蝇2龄幼虫体内的几丁质酶活性呈下降趋势,而斑翅果蝇2龄幼虫体内的几丁质酶活性则呈上升趋势。另外,亚致死浓度的氟铃脲可明显抑制黑腹果蝇体内几丁质酶的活性。表明昆虫生长调节剂氟铃脲和虱螨脲对果蝇有较强的毒力,氟铃脲的毒力高于虱螨脲,且果蝇体内几丁质酶的活性与氟铃脲和虱螨脲密切相关。

Effects of two insect growth regulators on Drosophila melanogaster and Drosophila suzukii

In order to investigate the toxicity mechanism of the insect growth regulators hexaflumuron and lufenuron on Drosophila melanogaster and D. suzukii, the virulence of hexaflumuron and lufenuron on the 2nd-instar larvae of two Drosophila species was determined with laboratory bioassays. The effect on chitinase activity of two Drosophila species was also determined under the treatment of sub-lethal dose LC₁₀ and LC₂₀ of hexaflumuron and lufenuron. The results showed that the mortality of D. melanogaster and D. suzukii increased significantly with the increase of treating time and concentration of hexaflumuron and lufenuron. The mortality of two Drosophila species exposed to hexaflumuron was 83.33%, which was higher than that of D. melanogaster (65.00%) and D. suzukii (66.66%) exposed to lufenuron. The chitinase activity in the 2nd-instar larvae of D. melanogaster decreased after treatment for 24 h with lufenuron at the sublethal dose of LC₁₀ and LC₂₀, while increased in D. suzukii. Moreover, the sublethal dose of lufenuron significantly inhibited the chitinase activity of D. melanogaster. It indicated that the insect growth regulators had a strong toxic effect on D. melanogaster and D. suzukii; however, the toxicity of hexaflumuron on them was higher than that of lufenuron, which was closely related with the activity of chitinase.