Wang Zhiling,Yuan Yixin,Dong Rui,Zeng Ruihong,Zhao Xin,Xu Yanjie,Gao Junping,Hong Bo,Gu Zhaoyu
Floral fragrance is essential for the attraction of pollinators and responses to biotic and abiotic stresses. It also enhances the quality and economic value of plants. Phytohormones, acting as key signaling molecules, are crucial roles in regulating plant growth and development. However, the molecular mechanisms underlying the biosynthesis of fragrance-related volatiles and their crosstalk with other endogenous signals within plants remain largely unknown. Here, we identified a sesquiterpene synthase gene, CmEβFS , in chrysanthemum, which encodes a catalytic enzyme responsible for synthesizing the key fragrance-related compound ( E )-β-farnesene. We demonstrated that CmEβFS is negatively regulated by CmWRKY1, thereby inhibiting ( E )-β-farnesene biosynthesis. Furthermore, CmWRKY1 interacts with the salicylic acid (SA) receptor CmNPR3 to regulate SA-mediated CmEβFS transcription. Our findings reveal that SA regulates ( E )-β-farnesene biosynthesis by controlling CmEβFS expression via the CmWRKY1-CmNPR3 module during floral development. These findings enhanced our understanding of the mechanisms underlying SA-mediated regulation of volatile organic compounds (VOCs) biosynthesis and provided insights into improving floral fragrance.
Hyphantria cunea , a globally significant quarantine pest, causes severe ecological and economic impacts in invaded regions. Attractants are environment-friendly and valuable pest management tools for H. cunea control. In this study, we identified that the combination of β-ocimene with sex pheromone components was strongly attractive to H. cunea males. This attractant combination activates the Ras signaling pathway and stimulates Ca 2+ in male adults following exposure. Feeding and oviposition behavior results demonstrated that H. cunea prefers Morus alba over Platanus × acerifolia , Metasequoia glyptostroboides , and Taxodium distichum . In the fresh branches of M. alba with leaves, the relative abundance of β-ocimene (36.33 ± 0.41 %) was significantly higher than the other hosts. Electroantennography recordings, behavioral choice assays, and field trapping trials showed that the combination of β-ocimene with sex pheromone components significantly enhanced male response and attraction. The number of trapped males using β-ocimene/ sex pheromone blend was 3.7-fold higher than that of sex pheromone or β-ocimene alone in the field, indicating a synergistic effect of adding β-ocimene to sex pheromone. The molecular mechanism of β-ocimene/sex pheromone synergism was further analyzed. After exposure to the attractant, the Ras signaling pathway in the heads of males are activated ( HcILP and HcPLCε1 are upregulated, while HcRasGAP and HcPLD are downregulated), which further stimulates the expression of IP3 and Ca 2+ . The activation of Ca 2+ may be the key reason for its higher attraction to males. These findings provide a theoretical basis for the selection and mechanistic understanding of attractants for H. cunea , offering insights for attractant-based pest control strategies.
危险品化学品经营许可证（带存储）