Young Goji Fruit Volatiles Regulate the Oviposition Behavior and Chemosensory Gene Expression of Gravid Female Neoceratitis asiatica

The goji fruit fly, <i>Neoceratitis asiatica</i>, is a major pest on the well-known medicinal plant <i>Lycium barbarum</i>. Dissecting the molecular mechanisms of the oviposition selection of <i>N. asiatica</i> regarding the host plant will help to identify new strategies for pest fly control. However, the molecular mechanism of chemical communication between the goji fruit fly and the host goji remains unclear. Hence, our study found that young goji fruit volatiles induced the oviposition response of gravid female <i>N. asiatica</i>. After <i>N. asiatica</i> was exposed to young goji fruit volatiles, the expression of six chemosensory genes (<i>NasiOBP56h3</i> and <i>OBP99a1</i> in the antennae; <i>OBP99a2</i>, <i>OBP99a3</i> and <i>CSP2</i> in the legs; and <i>OBP56a</i> in the ovipositor) was significantly upregulated in different organs of female <i>N. asiatica</i> compared with the group without odor treatment according to transcriptome data. Further results of qPCR verification show that the expression levels of the six selected upregulated genes after the flies were exposed to host plant volatiles were mostly consistent with the results of transcriptome data. We concluded that six upregulated genes may be involved in the recognition of young goji fruit volatiles by gravid female <i>N. asiatica</i>. Our study preliminarily identifies young goji fruit volatiles as a key factor in the oviposition behavior of <i>N. asiatica</i>, which will facilitate further studies on the mechanisms of host oviposition selection in <i>N. asiatica</i>.