State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
Ling-Qiao Huang
State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
Jun-Feng Dong
Forestry College, Henan University of Science and Technology, Luoyang, China
State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
Antennae are often considered to be the nostrils of insects. Here, we sequenced the transcriptome of the pheromone gland-ovipositor complex of Helicoverpa assulta and discovered that an odorant receptor (OR) gene, HassOR31, had much higher expression in the ovipositor than in antennae or other tissues. To determine whether the ovipositor was involved in odorant detection, we co-expressed HassOR31 and its co-receptor, HassORco, in a Xenopus oocyte model system, and demonstrated that the OR was responsive to 12 plant odorants, especially Z-3-hexenyl butyrate. These odorants elicited electrophysiological responses of some sensilla in the ovipositor, and HassOR31 and HassORco were co-expressed within ovipositor sensilla. Two oviposition preference experiments showed that female moths lacking antennae still preferentially selected oviposition sites containing plant volatiles. We suggest that the expression of HassOR31 in the ovipositor of H. assulta helps females to determine precise egg-laying sites in host plants.
