Abstract

Fruit ripening is under strict genetic and epigenetic control. Work on understanding this important developmental process has focused on tomato as a model system and this will be the main subject of the talk. Tomato has been selected as the model because it is one of the most important fruit crops in the world by volume consumed. It is also a major component of healthy diets providing ready sources of vitamins A, C, E and K, minerals including K and Fe and numerous secondary metabolites including carotenoids and anthocyanins that act as antioxidants. Additionally amongst major crops, it is uniquely appropriate to unravel the biological basis of many important crop traits due to the genetic, epigenetic and genomic resources available. The talk will describe: (1) Progress on understanding the high level regulatory network that controls ripening in tomato using information from non-ripening mutants and how similar families of regulatory genes are likely involved in ripening in all fleshy fruit species. (2) How the tomato genome sequence and systems biology approaches have provided new tools to link the major regulators to the down steam effectors directly controlling changes in colour, texture and flavour. (3) How the analysis of the gene regulatory networks in combination with studies of quantitative trait loci (QTL), underpinning quality traits, are leading to an understanding of the mechanistic basis of fruit ripening including the isolation of genes controlling fruit softening and shelf life (4) Evidence that both genetic and epigenetic factors combine to control the ripening process.

Understanding the fundamental genetic and epigenetic mechanisms controlling ripening is providing the basis for developing new and improved tomato lines.