Physiological, Transcriptional, and Metabolic Variations During Dormancy Release Across Potato Cultivars Revealed by...

Tuber dormancy length is a key agronomic trait determining potato storage quality and planting suitability, yet the underlying molecular regulatory mechanisms remain poorly understood. In this study, we perform a time-course physiological, transcriptomic, and metabolomic analysis of a long-dormancy cultivar 'Chuanliangshu 10' and a short-dormancy cultivar 'Favorita' at harvest and storage. The short-dormancy cultivar 'Favorita' exhibits a significantly faster conversion rate of starch to soluble sugars during storage compared to 'Chuanliangshu 10'. Integrated transcriptomic and metabolomic analyses revealed that 'Favorita' likely accelerates dormancy release and sprouting through the coordinated regulation of multiple metabolic pathways. First, the expression of S-adenosyl-L-homocysteine hydrolase genes (SAHH1/2) in the cysteine and methionine metabolism pathway is significantly up-regulated, accompanied by a marked accumulation of the key metabolite glutathione (GSH). Second, the phenylalanine ammonia-lyase gene (PAL) is continuously and strongly up-regulated during dormancy release, coinciding with the accumulation of the intermediate metabolites fumarate and succinate of the phenylalanine metabolism pathway. Third, expression of the zeatin-deactivating gene CKX is strongly suppressed, resulting in zeatin accumulation and thereby promoting tuber sprouting. Last but not least, the pentose phosphate pathway genes including PGD, RPIA and TKTA are significantly upregulated during storage, indicating activation of this pathway. Collectively, this study systematically elucidates the physiological, transcriptomic, and metabolomic differences between potato cultivars with contrasting dormancy characteristics, providing a theoretical foundation and candidate gene resources for precisely regulating tuber dormancy and improving potato storage traits.