Overexpression of a Soybean Cytochrome P450 Gene, GmCYP, Improves Drought and Insect Tolerance in Tobacco

Pests and environmental factors are normally considered as ones of the most widespread stresses that lead to detrimental effects on crop production and quality. Cytochrome P450s (CYPs) are a large protein family which mediates many physiological activities via the biosynthesis of secondary metabolites and detoxifying pathways. Additionally, by controlling phytohormones and secondary metabolite synthesis and accelerating reactive oxygen species (ROS) scavenging, CYPs have the ability to promote plants' molecular and chemical defense mechanisms, making them significant targets for genetic engineering in order to strengthen plant defense against environmental stresses. In this study, the GmCYP gene was transformed into tobacco ( N.tabacum cultivar K326) via Agrobacterium -mediated transformation for the study of transgenic plants' resistance to environmental stresses. Under the drought treatment, transgenic tobacco plants displayed changes in metabolite profiling analysis, such as considerably lower chlorophyll degradation, higher proline accumulation, higher rate of antioxidant (POD) activity, indicating their advanced abiotic stress tolerance phenotype. At the same time, their growth and development characteristics remained unchanged as compared to the wild type. Furthermore, in transgenic tobacco plants, caterpillars showed depleted growth features, such as delayed life cycles, shorter lengths, and lower weights, proving enhanced pest resistance of CYP transgenic plants. Therefore, these findings imply that overexpression of GmCYP impacts drought stress tolerance as well as insect resistance, and this candidate gene has potential for further research in the crop improvement program.