Potato and onion are major UK and worldwide crops required year-round by consumers and processors. Due to seasonal production, long term storage is necessary, during which produce must be maintained with good quality for fresh consumption and processing, and in a nutritious state. Potato tubers and onion bulbs are natural over-wintering structures with a tendency to resume growth during storage, resulting in sprouted produce that is unattractive and unsaleable, or unsuited to processing due to compositional changes such as increased sugar levels. Multiple strategies are used to extend dormancy and minimise sprouting and waste, including low temperature storage and application of sprout suppressants such as chlorpropham, maleic hydrazide or ethylene. Such treatments are not fully effective as quality deterioration may occur even if sprouting is inhibited and legislation increasingly limits use of many of these chemicals. In addition, long-term cold storage is a major economic cost with a substantial carbon footprint. Development of alternative strategies to maintain tubers and bulbs in a dormant state and long-term suppression of sprouting are top industry priorities. Genetic studies in potato have shown that inheritance of tuber dormancy characteristics is affected by several genes acting alone or in combination, but the identity of these genes is unknown. Despite substantial progress, a full understanding of the biology of dormancy and sprouting has not yet emerged, and this substantially hampers development of new strategies for storage, and breeding of new varieties with better dormancy and sprouting behaviours. Fortunately recent advances in the field of molecular biology allow us to make major advances to address these issues. Scientific studies have revealed common roles in potato and onion for several plant hormones including abscisic acid, ethylene, gibberellins and cytokinins, in regulation of dormancy, and sprout growth, suggesting that knowledge of one commodity further our understanding of another. This project will benefit from major advances in potato genetics, especially publication of the genome sequence, as well as huge developments in DNA sequencing technologies which now enable in-depth analysis of the relatively unexplored but highly complex onion genome. New, powerful potato genetic resources will allow us to pinpoint the position and identity of genes that exert the greatest control of dormancy and sprouting. These resources include large mapping populations, developed by crossing highly divergent parents. Preliminary studies have already revealed genomic regions containing key genes that can drive crop improvement and new management methods. The assembled research consortium brings together James Hutton Institute, Cranfield University, Imperial College London and Greenwich University, providing a wealth of experience in genomics, genetics, molecular biology, physiology, agronomy and storage of potato and onion. Project outcomes will include (1) identification of key genes in potato and onion, their variant forms and regulatory mechanisms that underpin potato tuber dormancy, (2) development of genome-wide data on major genes in onion bulb dormancy and sprouting, and (3) comparison of shared and distinctive elements of dormancy and sprouting control in potato and onion, leading to elucidation of key physiological and molecular control steps. Through involvement of industry representative bodies and companies, information generated can readily be translated towards enhanced, variety-specific storage regimes, enabling reduced chemical usage and less reliance on expensive low temperature storage. Knowledge of key regulatory genes can in the longer term be adopted by breeders to develop potatoes with better dormancy characteristics.