College of Plant Protection, Shanxi Agricultural University, Taiyuan, Shanxi 030031, China; Shanxi Key Laboratory of Integrated Pest Management in Agriculture, Taiyuan, Shanxi 030031, China.
College of Plant Protection, Shanxi Agricultural University, Taiyuan, Shanxi 030031, China.
Pestic Biochem Physiol. 2024 Jun;202:105939. doi: 10.1016/j.pestbp.2024.105939. Epub 2024 Apr 30.
The brown planthopper (BPH), Nilaparvata lugens is a devastating agricultural pest of rice, and they have developed resistance to many pesticides. In this study, we assessed the response of BPH nymphs to nitenpyram, imidacloprid, and etofenprox using contact and dietary bioassays, and investigated the underlying functional diversities of BPH glutathione-S-transferase (GST), carboxylesterase (CarE) and cytochrome P450 monooxygenase (P450) against these insecticides. Both contact and ingestion toxicity of nitenpyram to BPH were significantly higher than either imidacloprid or etofenprox. Under the LC concentration of each insecticide, they triggered a distinct response for GST, CarE, and P450 activities, and each insecticide induced at least one detoxification enzyme activity. These insecticides almost inhibited the expression of all tested GST, CarE, and P450 genes in contact bioassays but induced the transcriptional levels of these genes in dietary bioassays. Silencing of NlGSTD2 expression had the greatest effect on BPH sensitivity to nitenpyram in contact test and imidacloprid in dietary test. The sensitivities of BPH to insecticide increased the most in the contact test was etofenprox after silencing of NlCE, while the dietary test was nitenpyram. Knockdown of NlCYP408A1 resulted in BPH sensitivities to insecticide increasing the most in the contact test was nitenpyram, while the dietary test was imidacloprid. Taken together, these findings reveal that NlGSTD2, NlCE, and NlCYP408A1 play an indispensable role in the detoxification of the contact and ingestion toxicities of different types of insecticides to BPH, which is of great significance for the development of new strategies for the sucking pest control.
褐飞虱（Nilaparvata lugens）是水稻的毁灭性农业害虫，它们已经对许多杀虫剂产生了抗性。在本研究中，我们使用接触和饮食生物测定法评估了 BPH 若虫对吡虫啉、噻虫啉和乙虫腈的反应，并研究了 BPH 谷胱甘肽-S-转移酶（GST）、羧酸酯酶（CarE）和细胞色素 P450 单加氧酶（P450）对这些杀虫剂的潜在功能多样性。吡虫啉对 BPH 的接触毒性和摄食毒性均明显高于噻虫啉或乙虫腈。在每种杀虫剂的 LC 浓度下，它们都引发了 GST、CarE 和 P450 活性的明显反应，并且每种杀虫剂都诱导了至少一种解毒酶活性。这些杀虫剂几乎抑制了接触生物测定中所有测试的 GST、CarE 和 P450 基因的表达，但在饮食生物测定中诱导了这些基因的转录水平。在接触测试中，NlGSTD2 表达的沉默对 BPH 对吡虫啉的敏感性影响最大，而在饮食测试中，对 BPH 对噻虫啉的敏感性影响最大。在接触测试中，沉默 NlCE 后 BPH 对杀虫剂的敏感性增加最多的是乙虫腈，而在饮食测试中，增加最多的是吡虫啉。沉默 NlCYP408A1 导致 BPH 对杀虫剂的敏感性增加最多的是接触测试中的吡虫啉，而饮食测试中的是噻虫啉。综上所述，这些发现表明，NlGSTD2、NlCE 和 NlCYP408A1 在 BPH 对不同类型杀虫剂的接触毒性和摄食毒性的解毒中发挥了不可或缺的作用，这对于开发新的刺吸式害虫防治策略具有重要意义。
