Environmental, genetic and physiological factors governing potato endodormancy: from tuber development to...

Potato tuber dormancy and sprouting are complex traits with major implications for storage, quality, and postharvest management. Historically, these traits were controlled using chlorpropham (CIPC); however, following its ban in 2019 in the European Union, research aimed at understanding and managing dormancy and sprouting has increased substantially. Integrating findings across studies remains challenging due to the complexity of these traits, gaps in current knowledge, and differences in phenotyping approaches. In this review, we critically examine the challenges associated with evaluating dormancy and dormancy break progression and the current state of the knowledge across key developmental stages, from tuber formation, dormancy maintenance, to dormancy break. During tuber formation, we explore environmental signals that influence tuber induction and may contribute to dormancy extension, the reallocation of sugars from leaves to stolons, and the crosstalk amongst regulatory compounds. For dormancy maintenance, we analyse mechanisms of cell cycle arrest and highlight the roles of plant growth regulators in maintaining quiescence. Dormancy break is discussed in relation to sugar metabolism, symplastic reconnection, cell cycle reactivation, reactive oxygen species dynamics, and the influence of gibberellins and cytokinins. We also provide an overview of quantitative trait loci (QTLs) associated with dormancy and sprouting identified across multiple studies. By structuring this synthesis around developmental stages rather than individual processes, we identify critical research gaps to support future research aimed at improving dormancy control in potatoes.