Exogenous trehalose enhances heat tolerance in Ginkgo biloba by activating GbTPS1-mediated sugar and secondary metabolism pathways

Heat waves increasingly threaten the yield and quality of leaf-use Ginkgo biloba . Here we show that a foliar 20 mmol L⁻¹ trehalose (Tre) treatment markedly elevates thermotolerance, with efficacy observed under both controlled laboratory conditions and field environments. Under heat stress (HT), Tre (HTTre) delayed wilting, lowered the heat injury index (HII), accelerated early endogenous trehalose accumulation, enhanced SOD/POD/CAT activities, reduced MDA/H₂O₂, and maintained chlorophyll a/b, indicating preserved photosynthetic capacity and membrane integrity. RNA-seq at 24 h revealed 2320 Tre-responsive DEGs (HTTre vs HT): up-regulation of cell-wall organization, xyloglucan metabolism, Ca²⁺ binding, defense and antioxidant terms, with down-regulation of auxin-activated signaling and senescence. Widely targeted metabolomics showed Tre-driven enrichment of phenylpropanoid/flavonoid/terpenoid pathways and suppression of oxidative phosphorylation and the TCA cycle, suggesting a reallocation of energy toward defense. Multi-omics integration highlighted strengthened sugar metabolism and energy signaling; a trehalose-6-phosphate synthase gene GbTPS1 was strongly induced by Tre/heat, most tightly correlated with trehalose content, and functionally validated. GbTPS1 overexpression increased trehalose, boosted antioxidant capacity, and improved heat survival, whereas GbTPS1 silencing heightened ROS and injury. A summer field trial confirmed practical efficacy. Together, Tre enhances G. biloba thermotolerance by coupling sugar signaling with reinforced cell wall and antioxidant/secondary-metabolism networks, and GbTPS1 emerges as a tractable target for improving heat tolerance in woody crops. • Exogenous trehalose (Tre, 20 mM) boosts Ginkgo biloba heat tolerance. • Multi-omics reveals Tre-driven energy reallocation toward defense. • Tre application strengthens cell wall and antioxidant networks. • The trehalose-6-phosphate synthase gene GbTPS1 is key. • Foliar Tre treatment is effective in summer field conditions.