Insect gustatory receptors are a crucial class of chemoreceptors that can detect external environmental stimuli and influence insect behaviors such as host selection, feeding, mating, and oviposition. This study focused on the invasive pest Tuta absoluta (Meyrick) that affected tomatoes. To elucidate the characteristics of the gustatory receptor (GR) gene family in T. absoluta and investigate the expression patterns of GR genes across different developmental stages, we employed bioinformatics approaches to identify, chromosomally locate, conduct phylogenetic analysis, and analyze age-stage expression profiles of the GR genes in T. absoluta. The results indicated that 62 GR genes of the T. absoluta moth were identified and distributed on 19 chromosomes. The length of the encoded protein sequence ranged from 318 to 2034 bp, with an average of 5 exon fragments and 1 to 7 transmembrane regions. Phylogenetic analysis revealed that the GR genes of the T. absoluta could be categorized into four distinct subfamilies: bitter taste receptors (35 genes), carbon dioxide receptors (1 gene), sugar receptors (5 genes), and Gr43a-like receptors (7 genes). The remaining genes have not been classified yet. Expression analysis across different developmental stages revealed that the GR genes of the T. absoluta exhibited significant variation in expression levels throughout its life cycle. The research results provided a solid foundation for further elucidating the functions of gustatory receptor genes in the T. absoluta and uncovering its co-evolutionary relationship with host plants. These findings offered scientific evidence for controlling the T. absoluta by functional plants and lay the foundation for developing novel pest control technologies from a gustatory receptor perspective.

The aim of this study was to investigate the geographical distribution and the spread front of Tuta absoluta in the southwest, central and southern parts of China through a field survey, and to find out the distribution of T. absoluta in southwest China and its spread to neighboring provinces. The survey covered 192 townships in 100 counties in the provinces of Yunnan, Guizhou, Sichuan, Chongqing, Xizang, Hubei, Hunan, Guangxi Zhuang Autonomous Region and Guangdong Provinces (municipalities directly under the central government and autonomous regions). The results showed that T. absoluta occurred in 12 townships in 10 counties of Yunnan Province, 25 townships in 13 counties of Guizhou Province, 19 townships in 11 counties of Chongqing Municipality and 4 townships in 3 counties of Guangxi Zhuang Autonomous Region. In Sichuan Province, 30 counties and 47 townships, 22 counties and 33 townships found T. absoluta distribution; in Hubei Province, 7 counties and 16 townships, 5 counties and 11 townships found T. absoluta distribution; in Hunan Province, 20 counties and 53 townships, 10 counties and 24 townships found T. absoluta distribution. In 2 counties and 4 townships in Tibet Autonomous Region and 4 counties and 12 townships in Guangdong Province, only one township was found to be affected by the T. absoluta, which was the Naxi ethnic township in Mangkang County, Chamdo City, Xizang Autonomous Region, and the Sanshui Yao Township in Lianzhou City, Qingyuan City, Guangdong Province, respectively. This survey clarified the distribution area of T. absoluta in the southwest region and the frontiers of its spread to the surrounding provinces, and provided data reference for the monitoring and early warning of T. absoluta as well as the scientific prevention and control of T. absoluta.

Tuta absoluta (Meyrick), native to Peru, South America, is a worldwide quarantine invasive pest and has spread to more than 110 countries and regions, posing a serious threat to the tomato industry. Due to the negative effects of chemical control, the research and development as well as application of green control technologies are particularly important. This paper reviews the research progress of green prevention and control technologies, including "push-pull" technologies, physicochemical trapping and control technologies, biological control technology and other new concepts of prevention and control. The aim of this paper is to provide tomato growers with scientific and effective control guidance for the prevention and control of T. absoluta, reduce the use of chemical pesticides, and guarantee the sustainable development of the tomato industry and the quality and safety of agricultural products.