Trichomes are key physical and chemical barriers in plants against herbivorous insects, but their development and role in strawberry insect resistance remain unclear. This study found that overexpressing FaGAPC2, a glycolytic gene, increased glandular trichome density and nonglandular trichome density while raising lignin content by 26.8%. Multiomics analysis revealed that FaGAPC2 activates phenylpropanoid biosynthesis, boosting levels of hydroferulic acid, kaempferol, and tetrandrine, reducing Tetranychus urticae damage by 61.5-82.8%. Y1H, LUC, and EMSA assays confirmed that bZIP transcription factor FaTRAB1 directly activates FaGAPC2. FaTRAB1 overexpression enhanced trichome density, pectin/cellulose content, and lignin accumulation by upregulating FaCSE and FaHCT while increasing the leaf thickness, forming a robust mechanical barrier. These findings demonstrate how the FaTRAB1-FaGAPC2 module enhances mite resistance via trichome development, lignin deposition, and insecticidal metabolite synthesis, offering new strategies for breeding pest-resistant strawberries and developing plant-based acaricides.
Yang et al. (Sat,) studied this question.