Abstract: Plant-derived volatiles are important for guiding herbivorous insects to their host plants. Jaapiella sp. (Diptera: Cecidomyiidae) is the most serious pest of Lycium barbarum. The young flower buds of L. barbarum are attractive to females of Jaapiella sp. for oviposition in the field. In this study, we compared response of Jaapiella sp. to volatiles from flower buds of L. barbarum at different stages, and clarified the crucial semiochemicals attracting Jaapiella sp. to lay eggs. Volatiles from young and mature flower buds were collected using SPME, and then identified and quantified by gas chromatography-mass spectrometry (GC-MS). Both electrophysiological and behavior experiments were conducted to measure the attraction of eight synthetic compounds to females and screen the crucial components based on gas chromatography-electroantennogram detection (GC-EAD) and Y-tube bioassays, respectively. Results showed that qualitative and quantitative diffe-rences between two odor profiles. Consistent electroantennographic response was observed for eight compounds from headspace collections, of which five synthetic compounds (3-carene, camphene, terpinolene, d-limonene, and (+)-pinene) were essential for significant preference or avoidance. Our results indicated that these compounds from L. barbarum flower buds could be effective candidates as oviposition attractant or repellents of Jaapiella sp., which would be helpful in the exploitation of new control agent to Jaapiella sp. in the field.

Key words: Jaapiella sp., plant olatiles, SPME, GC-MS, GC-EAD, Y-tube olfactometer