The corn borer is a world-wide agricultural pest. In this study, a high-efficiency RNAi method was explored to knock down the neuropeptide F (NPF) to determine if NPF regulates larval feeding in the Asian corn borer, Ostrinia furnacalis. Results showed that the expression peaks of npf mRNA in both midgut and fat body are at 28 h of early 5th instar larvae. When NPF was knocked down either by feeding dsNPF-containing artificial diet or direct dsNPF injection into the 5th instar larvae, npf expression was effectively inhibited in the midgut. Larval feeding, body weight and development time were significantly impacted. In contrast, the expression of the npf receptors npfr1 and npfr2 in fat body of 5th instar larvae was significantly increased by dsNPF injection. These results indicate that NPF can be effectively knocked down in O. furnacalis, and dsNPF by injection is an effective and fast way to silence npf expression. This study provides a critical basis for further exploration in mechanism of feeding regulation in O. furnacalis.

玉米bore是一种世界性的农业害虫。在这项研究中，探索了一种高效的RNAi方法来敲除神经肽F（NPF），以确定NPF是否调节亚洲玉米bore（Ostrinia furnacalis）的幼虫摄食。结果表明，中肠和脂肪体中npf mRNA的表达高峰均在第5龄幼虫的28 h。当NPF通过将含有dsNPF人工食物或直接dsNPF注射到5龄幼虫或者击倒，NPF表达有效抑制中肠。幼虫的摄食，体重和发育时间受到显着影响。与此相反，表达NPF受体npfr1和npfr2dsNPF注射显着增加了5龄幼虫脂肪体内的脂肪。这些结果表明NPF可以有效地在O.furnacalis中被击倒，并且通过注射dsNPF是沉默npf表达的有效且快速的方法。这项研究为进一步探索O. furnacalis的饲料调节机制提供了重要基础。