Guangdong Engineering Research Center for Insect Behavior Regulation; Key Laboratory of Bio-Pesticide Innovation and Application, College of Agriculture, South China Agricultural University, Guangzhou, China.
State Key Laboratory of Rice Biology; Ministry of Agriculture, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou, China.
Pest Manag Sci. 2020 Jul;76(7):2453-2464. doi: 10.1002/ps.5786. Epub 2020 Mar 2.
The Asian citrus psyllid (ACP), Diaphorina citri, is one of the major pests in citrus production because it transmits huanglongbing, a devastating disease of citrus plants. Odourant-binding proteins (OBPs) play an important role in the olfactory perception of insects. Revealing the function of DcitOBPs is beneficial to the development of new ACP management strategies.
An analysis of the components of volatiles from the new shoots of six host plant species showed that β-caryophyllene was the characteristic volatile compound in flushing shoots and the most abundant volatile compound in three of the six tested ACP host plant species. The tissue expression profiles of nine known DcitOBPs were analyzed based on a transcriptome database, and DcitOBP3 and DcitOBP6 exhibited high expression in the antennae of both sexes and the ovipositor of females. The binding ability of two recombinant proteins with eight ligands was studied through competitive binding analysis; the results showed that DcitOBP6 exhibited stronger binding to β-caryophyllene. Behavioural trials indicated that sexually mature female adults of D. citri were significantly attracted to β-caryophyllene at concentrations of 0.1 μL mL and 10 μL mL . RNAi analysis in female D. citri showed that the reduction of DcitOBP6 transcript abundance led to a decrease in antennae EAG activity and behavioural responses to β-caryophyllene.
The results demonstrate that DcitOBP6 is involved in the perception of an important host plant volatile, β-caryophyllene, in the ACP, and provide a theoretical foundation for behavioural interference in ACP management.
亚洲柑橘木虱（ACP），Diaphorina citri，是柑橘生产中的主要害虫之一，因为它传播黄龙病，这是柑橘植物的一种毁灭性疾病。气味结合蛋白（OBPs）在昆虫的嗅觉感知中起着重要作用。揭示 DcitOBPs 的功能有利于开发新的 ACP 管理策略。
对六种寄主植物新梢挥发物成分的分析表明，β-石竹烯是展梢的特征挥发性化合物，也是六种测试的 ACP 寄主植物中三种的最丰富挥发性化合物。根据转录组数据库分析了 9 种已知的 DcitOBPs 的组织表达谱，DcitOBP3 和 DcitOBP6 在两性触角和雌性产卵器中表达量高。通过竞争结合分析研究了两种与八种配体结合的重组蛋白的结合能力；结果表明，DcitOBP6 对 β-石竹烯具有更强的结合能力。行为试验表明，性成熟的 D. citri 雌成虫对浓度为 0.1 μL/mL 和 10 μL/mL 的 β-石竹烯有明显的吸引力。D. citri 雌虫的 RNAi 分析表明，DcitOBP6 转录丰度的降低导致触角 EAG 活性和对 β-石竹烯的行为反应降低。
结果表明，DcitOBP6 参与了 ACP 对重要寄主植物挥发性物质 β-石竹烯的感知，为 ACP 管理中的行为干扰提供了理论基础。
