Integrated transcriptomic and metabolomic analyses reveal the effects of climate on volatiles in grape (Vitis vinifera L. cv. Centennial Seedless) and their underlying molecular mechanisms

• Integrated multi-omics reveals climate effects on grape volatile aroma. • High-temperature stress inhibits volatile aroma synthesis in 'Centennial Seedless'. • High-temperature stress reduces terpene content in the pre-developmental fruit of 'Coreless White Chicken Heart Grapes'. • DXS, AACT, TPS65 , and TPS07 may be the key genes. Climate change-induced temperature fluctuations significantly impact grape aroma quality. This study employed integrated transcriptomic and metabolomic analyses to examine temperature effects on volatiles in 'Centennial Seedless' grapes from high-temperature (Turpan) and low-temperature (Urumqi) regions across four developmental stages. Metabolomic profiling identified 143 volatile compounds. Results revealed distinct accumulation patterns: early stages showed higher levels of (E)-2-hexenol and hexanal in cooler climates, while terpene concentrations (e.g., linalool, geraniol) were significantly higher during late maturation in low-temperature regions. Transcriptomic data indicated 2160 genes upregulated and 2175 downregulated at S1 stage under cooler conditions, with key terpene synthesis genes ( DXS, DXR, TPS ) upregulated. This study confirms that high-temperature stress inhibits typical "rose-scented" aroma formation primarily through transcriptional suppression of terpenoid biosynthesis, especially TPS genes. Cooler climates enhance terpenoid production, preserving Muscat aroma. These findings provide a theoretical basis for molecular breeding and cultivation strategies to improve aroma quality under global warming.