Abstract：
The cabbage stem flea beetle (CSFB, Psylliodes chrysocephala) is a key pest of oilseed rape. The ban on neonicotinoids in the European Union due to environmental concerns and the emergence of pyrethroid-resistant populations have made the control of CSFB extremely challenging. In search of a solution, we have recently shown that RNA interference (RNAi) has potential in the management of CSFB. However, the previously tested target genes for RNAi-mediated pest control (subsequently called target genes) exhibited moderate and slow-acting lethal effects. In this study, 27 double-stranded RNAs (dsRNAs) were orally delivered to identify highly effective target genes in CSFB adults by leveraging the findings of a genome-wide RNAi screen in Tribolium castaneum. Our screen using 500 ng of dsRNA identified 10 moderately effective (> 50% mortality) and 4 highly effective target genes (100% mortality in 8-13 days). The latter mainly included proteasome subunits. Gene expression measurements confirmed target gene silencing and dose-response studies revealed LD50 values as low as ~20 ng in 14 days following a single exposure to dsRNA. Four highly effective dsRNAs also inhibited leaf damage (up to ~75%) and one affected locomotion. The sequences of promising target genes were subjected to in silico target prediction in non-target organisms, for example, beneficials such as honeybees, to design environmentally friendly dsRNAs. Overall, the study provides valuable insights for the development of dsRNA-based insecticides against CSFB.
摘要：
卷心菜茎跳蚤甲虫(CSFB，白鲸）是油菜的主要害虫。由于环境问题和拟除虫菊酯抗性人群的出现，欧盟对新烟碱的禁令使CSFB的控制极具挑战性。在寻找解决方案时，我们最近证明RNA干扰（RNAi）在CSFB的管理中具有潜力。然而,先前测试的RNAi介导的害虫防治的靶基因(随后称为靶基因)表现出中等和缓慢作用的致死作用.在这项研究中,通过利用Castaneum中全基因组RNAi筛选的发现，口服递送了27个双链RNA（dsRNA），以鉴定CSFB成人中高效的靶基因。我们使用500ngdsRNA的筛选鉴定出10个中等有效(>50%死亡率)和4个高度有效的靶基因(在8-13天内100%死亡率)。后者主要包括蛋白酶体亚基。基因表达测量证实了靶基因沉默和剂量反应研究揭示了在单次暴露于dsRNA后14天内LD50值低至〜20ng。四种高效的dsRNA也抑制叶片损伤(高达~75%)和一种影响运动。有希望的靶基因序列在非靶生物中进行了计算机靶标预测，例如,蜜蜂等受益者，设计环保的dsRNA。总的来说,该研究为开发基于dsRNA的抗CSFB杀虫剂提供了有价值的见解。
