LAUSR

Olfaction plays an essential role in insect behavior such as host location, foraging, mating and oviposition. The odorant receptor co-receptor (Orco) is an obligatory odorant receptor and indispensable in odor perception. Here, we characterized the Orco gene from the oriental fruit fly Bactrocera dorsalis (Hendel), a notorious agriculture pest. The olfactory deficiency mutants were generated by editing the BdorOrco gene using the CRISPR/Cas9 system. Electroantennograms (EAG) and olfactory preference assays confirmed that BdorOrco-/- mutant flies had reduced perception of methyl eugenol, β-caryophyllene and ethyl acetate. Oviposition bioassays showed that the eggs laid by BdorOrco-/- females mediated by benzothiazole and 1-octen-3-ol was significantly decreased. In addition, BdorOrco-/- mutant flies took significantly longer time to locate the food source compared with wild type (WT) flies. Altogether, our data indicated that Orco is essential for multiple physiological processes in B. dorsalis, and it expands our understanding on the function of insect Orco. This article is protected by copyright. All rights reserved.