关键词: 橘小实蝇, 嗅觉蛋白, 化学感受识别机制, 引诱剂, 行为调控剂

Abstract: True fruit flies are important insect pests attacking fruits and vegetables. The total damage caused by them worldwide is estimated to amount to be more than 2 billion US dollars annually. The oriental fruit fly, Bactrocera dorsalis, is one of the representatives of this kind of pests, causing serious losses to China’s citrus industry every year. The techniques based on male attractant and protein bait have been used in environment friendly strategies for pest monitoring and control. However, the performances of those baits in the field are unsatisfied and need to be further improved. With the reduction of the cost of high-throughput sequencing technology and the development of modern molecular biology technology, scientists proposed to discover the key molecular targets for olfaction by resolving the molecular mechanism of pest chemosensory first and develop more stable and efficient attractants with the identified new targets. In order to promote the development of behavioral regulation technology targeting key chemosensory molecules in B. dorsalis, we reviewed the research status of important chemicals regulating the behavior of B. dorsalis and the mechanism of chemosensory perception in this article. The important volatiles regulating the behavior of B. dorsalis include sex pheromones, plant volatiles and food-derived protein odors. Among them, the specific compounds identified by the first two have a clear relationship with the behavior of B. dorsalis adults. For example, pyrazine substances obtained from sex pheromones can attract females, methyl eugenol in plant volatiles can attract males, γ-octalactone can induce females to lay eggs; while the composition of food-derived protein odor is complex, although it has a certain efficacy in the field, there is a lack of function validation of specific compounds in female and male insect behavior. In the olfactory sensory mechanism, there is only a morphological description of the peripheral nerve sensilla and the central antennal lobe, and the function of different types of olfactory neurons is not clear. A large number of chemical sensory proteins have been identified in B. dorsalis, including 49 odorant binding proteins (OBPs), 60 odorant receptors (ORs), 23 ionotropic receptors (IRs) and 17 gustatory receptors (GRs), through bioinformatics analysis at present. However, the number of olfactory genes functionally analyzed is small. In conclusion, although some compounds with behavioral activity on B. dorsalis have been identified, and a large number of olfactory proteins have been used as candidate molecular targets, the corresponding relationship between “chemical substances-olfactory molecular targets and nerve-behavior” is lacking, which greatly limits the role of olfactory molecular targets in attractant development. Therefore, on this basis, we put forward a development strategy for the behavioral regulation technology of B. dorsalis based on olfactory key molecular targets, to provide new ideas for the design and screening of effective behavioral regulators of B. dorsalis.

Key words: Bactrocera dorsalis, olfactory protein, chemical sensory recognition mechanism, attractant, behavior regulator