Abstract: 【Aim】 This study aims to explore the olfactory learning capability of the male adults of the oriental fruit fly,  Bactrocera dorsalis (Hendel). 【Methods】 A classical olfactory conditioning procedure was adopted. The 14-17 day-old male adults of B. dorsalis were individually trained to associate odor with food in the laboratory, i.e., exposed to peppermint odor paired with 10% sucrose solution for appetitive conditioning and methyl eugenol (ME) paired with saturated salt solution for aversive conditioning. The change of the proboscis extension reflex was used as the criterion for conditioning. 【Results】 The proportion of proboscis extension reflex of male adults of B. dorsalis increased from 0% to 68% after appetitive conditioning, and decreased from 100% to 36.54% after aversive conditioning. And its variation was generated by a temporal relation between odor conditioned stimulus (CS) and food unconditioned stimulus (US) (paired). 【Conclusion】 These results indicate that male adults of B. dorsalis have a strong capacity to form an olfactory memory as a result of classical conditioning, while the contiguity of CS and US is a necessary condition of learning.

Key words: Bactrocera dorsalis, methyl eugenol (ME), associative olfactory conditioning, appetitive conditioning, aversive conditioning, classical conditioning, proboscis extension reflex (PER)