Mark J. Guiltinan

Chapter 4:Applications of Genomics to the Improvement of Cacao

The recent completion of the cacao genome sequences has revealed over 28u2009000 genes that encode the instructions for the growth and development of the chocolate tree. This chapter reviews the results of the cacao genomics revolution over the past several years and looks into the future impact that this will have on the development of the cacao varieties of the future. Genomic data have led to exciting advances in our understanding of the evolutionary forces acting over millions of year to shape the genetic diversity found in our germplasm collections and in wild populations today. Several key genes involved in important traits such as fruit color, disease resistance and the levels of health-promoting phytochemicals in seeds have been identified and functionally characterized. In parallel, exciting advances in understanding the genomes and life cycles of the most important cacao pathogens are described. A discussion of the future of cacao improvement and the impact of genomics on the acceleration of these efforts is presented.