Metabolomics and Transcriptomics Reveal the Role of the Terpene Biosynthetic Pathway in the Mechanism of Insect Resistance in Solanum habrochaites

Terpenes are a large variety of natural organic compounds that can enhance the resistance of plants to phytophagous insects through induction. In this study, differential expression genes and metabolites of Alice Craig (AC) and Solanum habrochaite (SH) were screened and analyzed by transcriptomics and metabolomics. The results show that terpene biosynthesis is one of the most crucial secondary metabolic pathways in plants. SH significantly accumulates more terpenes than AC by up regulating the expression of relevant genes. It is worth noting that virus-induced SlHDR silencing not only reduces the expression of downstream genes (SlTPS3, SlFPP, and SlGGPPS) in the terpene biosynthesis pathway, but also significantly affects the synthesis of related terpenoids, there by reducing the insect resistance of tomatoes. The results will be beneficial for understanding the synthesis mechanism of terpenoids in tomatoes and supply new genetic resources for the development of insect-resistant tomatoes.