Transcriptomics and targeted metabolomics uncover hormonal regulations of potato (Solanum tuberosum L.) tuber dormancy progression under ethylene treatment

Postharvest sprouting of potato ( Solanum tuberosum L.) tubers can compromise quality, shelf life, and marketability. Ethylene has emerged as an alternative to conventional sprout inhibitors, yet the molecular mechanisms underlying its suppressive effect remain poorly understood. Integrated transcriptomic and targeted metabolomic analyses were employed to elucidate hormone-mediated regulatory networks involved in ethylene-induced dormancy maintenance of potato tubers. Certified tubers of cv. Russet Burbank were treated continuously with ethylene (10 µL L −1 ) for 15 weeks, followed by three weeks of supplemental airflow after ethylene withdrawal. Sprout progression was monitored during the treatments, and primary meristem and tuber flesh tissues were sampled at various time-points for gene expression analysis and phytohormone profiling. Ethylene treatment effectively suppressed sprouting and triggered tissue-specific transcriptional responses, notably caused by a decrease in the abundance of transcripts involved in auxin ( IAA14, PIN3, ARF19 ), cytokinin ( LOG3, AHK4 ), and gibberellin ( GA20OX1, GA3OX1 ) pathways in meristem tissues, accompanied by sustained starch reserves and reduced contents of reducing sugars. However, the abundance of transcripts involved with ethylene biosynthesis and signaling ( ACS6, ACO4, ERF1A ), abscisic acid ( NCED3, PYL4 ), and jasmonic acid ( LOX2, MYC2 ) pathways increased. Phytohormone profiling further supported the observed transcriptome, with reduced zeatin and gibberellin A6 levels and elevated jasmonic acid derivatives in meristems. After ethylene treatment withdrawal, partial reactivation of gibberellin and cytokinin pathways marked a dynamic regulatory shift that coincided with dormancy release. Overall, our results demonstrate that ethylene coordinates tuber dormancy by suppressing growth-promoting signals and activating stress-related hormonal pathways, along with maintaining starch reserves and limiting the accumulation of reducing sugars in primary meristems. This study provides a molecular and metabolic framework for ethylene-based sprout suppression that could improve potato postharvest storage strategies.