Functional characterization of pheromone receptor candidates in codling mothCydia pomonella(Lepidoptera: Tortricidae)

Sex pheromones serve a critical role in Lepidopterans finding mates. Male moths perceive and react to sex pheromones emitted by conspecific females through a delicate pheromone communication system. Pheromone receptors (PRs) are the key sensory elements at the beginning of that process. The codling moth (Cydia pomnonella) is an important pome fruit pest globally and a serious invasive species in China. Pheromone-based techniques have been used successfully in monitoring and controlling this species. We conducted ribonucleic acid sequencing analysis of the codling moth antennal transcriptome and identified 66 odorant receptors (ORs) in a population from Xinjiang province, China, of which 14 were PRs, including two novel PRs (CpomOR2e and CpomOR73). Four PRs that contain full-length open reading frames (CpomOR1, OR2a, OR5, OR7) and four PRs with ligands that have not been reported previously (CpomOR1, OR2a, OR5, OR7) were selected to deorphanize in the heterologousXenopus oocyteexpression system. Specifically, we found that CpomOR2a and CpomOR5 responded to (E,E)-8, 10-dodecadien-1-yl acetate (codlemone acetate). Furthermore, CpomOR5 (EC50= 1.379 x 10(-8)mol/L) was much more sensitive to codlemone acetate than CpomOR2a (EC50= 1.663 x 10(-6)mol/L). Since codlemone acetate is an important component ofC. pomonellasex pheromone, our results improve the current understanding of pheromone communication in codling moths and will be helpful for the development of pest management strategies.

Automated summary

The study identified 66 odorant receptors in the codling moth, including 14 pheromone receptors, and found that CpomOR2a and CpomOR5 responded differently to codlemone acetate. This discovery improves the understanding of pheromone communication in codling moths and can aid in the development of pest management strategies.