Chemoreception is critical for insect behaviors such as foraging, host searching and oviposition. The process of chemoreception is mediated by a series of proteins, including odorant-binding proteins (OBPs), gustatory receptors (GRs), odorant receptors (ORs), ionotropic receptors (IRs), chemosensory proteins (CSPs) and sensory neuron membrane proteins (SNMPs). The tephritid stem gall fly, Procecidochares utilis Stone, is a type of egg parasitic insect, which is an effective biological control agent for the invasive weed Ageratina adenophora in many countries. However, the study of molecular components related to the olfactory system of P. utilis has not been investigated. Here, we conducted the developmental transcriptome (egg, first-third instar larva, pupa, female and male adult) of P. utilis using next-generation sequencing technology and identified a total of 133 chemosensory genes, including 40 OBPs, 29 GRs, 24 ORs, 28 IRs, 6 CSPs, and 6 SNMPs. The sequences of these candidate chemosensory genes were confirmed by BLAST, and phylogenetic analysis was performed. Quantitative real-time PCR (qRT-PCR) confirmed that the expression levels of the candidate OBPs varied at the different developmental stages of P. utilis with most OBPs expressed mainly in the pupae, female and male adults but scarcely in eggs and larvae, which was consistent with the differentially expressed genes (DEGs) analysis using the fragments per kilobase per million fragments (FPKM) value. Our results provide a significant contribution towards the knowledge of the set of chemosensory proteins and help advance the use of P. utilis as biological control agents.

化学感受对于昆虫的行为（例如觅食，寄主搜索和产卵）至关重要。化学感受的过程由一系列蛋白介导，包括味觉结合蛋白（OBP），味觉受体（GRs），味觉受体（OR），离子型受体（IR），化学感觉蛋白（CSP）和感觉神经元膜蛋白（ SNMP）。拟南芥茎gall蝇（Procecidochares utilis Stone）是一种卵寄生虫，在许多国家中它是一种有效的生物防治剂，用于入侵紫茎泽兰。然而，有关util鱼嗅觉系统的分子成分的研究尚未调查。在这里，我们使用下一代测序技术进行了P. utilis的发育转录组（卵，幼虫的第三龄幼虫，，雌性和雄性成虫），共鉴定了133个化学感应基因，包括40个OBP，29个GR，24个OR，28个IR，6个CSP和6个SNMP。通过BLAST确认这些候选化学感应基因的序列，并进行系统发育分析。定量实时PCR（QRT-PCR）证实，在不同发育阶段而变化的候选OBPs的表达水平P.刺大多数OBP主要在the，雌性和雄性成年动物中表达，但在卵和幼虫中很少表达，这与使用每千碱基每百万片段（FPKM）值的差异表达基因（DEG）分析相一致。我们的结果为化学感应蛋白的知识提供了重要的贡献，并有助于促进将P. utilis用作生物防治剂。