Genomics and Molecular Markers for Rice Grain Quality: A Review

Rice grain quality is a benchmark of rice breeding success. Current rice breeding programs consider grain characteristics that are preferred by consumers in the rice value chain. Specific traits of quality that suit the demands of stakeholders must be targeted before, during and after breeding of new varieties. Therefore, screening tools that are environmentally independent, cheap, robust and easy to use, such as molecular markers, are needed to facilitate timely and accurate selection of traits. As a multifaceted overall phenotype and consisting of several parameters ranging from physical, textural, aroma and increasingly nutritional properties, the selection for quality has not only become about which trait(s) to focus on but is rather an issue of the combination of traits that can be incorporated into a dream variety. The more traits that are available, the more markers we need to capture these traits and feed them into the breeding and selection pipelines. This chapter reviews progress made on genomics and the molecular markers developed for quality traits of rice grains. In addition, this chapter presents the increasing need for novel phenotypes in the form of metabolites that can be traced back to the genome of rice.