MEAM1烟粉虱隐种对三种新烟碱类杀虫剂交互抗药性差异的分子机制

Neonicotinoids are currently the most widely used insecticides in the chemical control of the whitefly, Bemisia tabaci. However, strong resistance has been developed because of the improperly overuse of the pesticide. In the former study, we found that Bemisia tabaci MEAM1 cryptic species exhibits significant different charactristics to imidacloprid, acetamiprid and thiamethoxam in the forming of resistance and cross resistance. Whether or not a different metabolic resistance mechanism or site of action involved in the resistance of B. tabaci to imidacloprid, acetamiprid and thiamethoxam? In this project, the susceptible strain and 3 resistant strains screened by imidacloprid, acetamiprid and thiamethoxam, respectively, were studied by transcriptome sequencing, to screen key genes involved in the differences of resistance and cross-resistance among the 3 neonicotinoids, and to construct the metabolic pathway which regulating and controlling the differences of resistance and cross-resistance to the 3 neonicotinoids, to illustrate the molecular mechanisms underlying the cross-resistance differences of B. tabaci MEAM1 cryptic species to this 3 neonicotinoids, and to provide theoretical and technical support to the whitefly resistance management, dosage reduction and effect enhancement of the pesticide.

新烟碱类杀虫剂是目前运用最广泛的烟粉虱Bemisia tabaci化学防治药剂，随着其在世界范围内的大面积使用，烟粉虱已对其产生抗药性。前期研究表明，MEAM1烟粉虱隐种对吡虫啉、噻虫嗪和吡虫清三种新烟碱类杀虫剂的抗性和交互抗性存在显著的差异性，是否MEAM1烟粉虱隐种对吡虫啉、吡虫清和噻虫嗪三种新烟碱类杀虫剂存在着不同的代谢抗性机制或者作用靶标？本项目拟以长期筛选建立的新疆MEAM1烟粉虱隐种敏感品系和吡虫啉、噻虫嗪及吡虫清抗性汰选品系为材料，通过转录组学手段，对MEAM1烟粉虱隐种敏感品系及不同抗性汰选品系进行转录组信息研究，解析MEAM1烟粉虱隐种对三种新烟碱类杀虫剂抗性及交互抗性差异相关的关键解毒酶及受体基因和代谢通路，明确MEAM1隐种对三种新烟碱类杀虫剂抗性及交互抗性差异的分子机制，为三种新烟碱类杀虫剂的抗性治理、减量使用和提高防治效果等提供科学依据。

新烟碱类杀虫剂是目前运用最广泛的烟粉虱化学防治药剂，随着其在世界范围内的大面积使用，烟粉虱已对其产生抗药性。前期研究表明，MEAM1烟粉虱隐种对吡虫啉、啶虫脒和噻虫嗪三种新烟碱类杀虫剂的抗性和交互抗性存在显著的差异性，是否MEAM1烟粉虱隐种对吡虫啉、啶虫脒和噻虫嗪三种新烟碱类杀虫剂存在着不同的代谢抗性机制或者作用靶标？本项目以长期筛选建立的新疆MEAM1烟粉虱隐种敏感品系和吡虫啉、噻虫嗪及吡虫清抗性汰选品系为材料，通过转录组学手段，对MEAM1烟粉虱隐种敏感品系及不同抗性品系进行转录组信息研究。发现三种新烟碱类杀虫剂中，吡虫啉处理相比于啶虫脒和噻虫嗪处理，更容易诱导大量抗药性相关基因的表达，尤其是P450基因，且吡虫啉诱导表达的抗性基因谱基本包含了噻虫嗪和啶虫脒诱导表达的主要抗性基因，噻虫嗪诱导表达的抗性基因与吡虫啉相比较少，啶虫脒诱导表达的抗性基因最少，这一点与抗性品系的抗性形成速度和交互抗性现实遗传力的结果基本一致，说明烟粉虱MEAM1隐种更容易对吡虫啉产生抗药性，且吡虫啉和噻虫嗪之间产生交互抗性的风险较高，啶虫脒与两种药剂产生交互抗性的风险相对较低，但是对吡虫啉产生高抗性的烟粉虱MEAM1隐种更容易对啶虫脒产生抗性。通过单一抗性和交互抗性转录组测序分析发现，细胞色素P450 4C1-like及其转录本是烟粉虱MEAM1隐种对三种新研究类杀虫剂产生抗性及交互抗性的主要调控基因，其他P450家族成员还有P450 6a13, P450 6a14, P450 6d4等。其他相关重要基因包括热激蛋白HSP 70、ABC、UGT等行使分子伴侣功能或参与到异源物质第二阶段代谢的关键基因。通过解析烟粉虱MEAM1隐种对三种新烟碱类杀虫剂抗性及交互抗性差异相关的关键解毒酶及受体基因和代谢通路，明确烟粉虱MEAM1隐种对三种新烟碱类杀虫剂抗性及交互抗性差异的分子机制，为三种新烟碱类杀虫剂的抗性治理、减量使用和提高防治效果等提供了科学参考依据。