Abstract:  【Aim】 Odorant binding proteins (OBPs) contribute to the remarkable sensitivity of insect olfactory system and play an important role in aphid alarm pheromone (E)-β-farnesene (EBF) communication. The turnip aphid, Lipaphis erysimi (Kaltenbach) is the major pest of cruciferous crops. To reduce pesticide application in vegetable fields, EBF appears to hold strong potential for aphid control. However, few studies about L. erysimi to EBF are known so far. 【Methods】 Two putative OBP genes, LeryOBP3 and LeryOBP7 encoding proteins with high affinity to EBF were cloned by PCR and RACE and characterized from L. erysimi, and their expression profiles at different developmental stages and in different tissues of wingless adults of L. erysimi were determined by RT-qPCR. 【Results】 The two genes cloned here, LeryOBP3 (GenBank no.: KJ703012) and LeryOBP7 (GenBank no.: KJ703013) share high amino acid sequence identities (94% and 88%, respectively) with ApisOBP3 and ApisOBP7, which encode proteins with affinity to EBF in Acyrthosiphum pisum (Harris). The full length of open reading frames of LeryOBP3 and LeryOBP7 are 357 and 468 bp, encoding 118 and 155 amino acids, respectively. Developmental expression profiles showed that the obvious expression peaks of LeryOBP3 and LeryOBP7 appeared at the adult stage, and tissue expression profiles showed that LeryOBP3 was expressed strongly in legs of adults while LeryOBP7 in adult antennae. 【Conclusion】 These results suggest that LeryOBP7 in the antennae might be responsible for the response of L. erysimi to EBF.

Key words: Lipaphis erysimi; alarm pheromone, odorant-binding protein, gene expression profile, real-time quantitative PCR