Marker-Assisted Breeding for Improving the Cooking and Eating Quality of Rice

Abstract

Cooking and eating quality of rice is determined by fragrance and starch physicochemical properties, comprising of apparent amylose content (AAC), gelatinization temperature (GT), gel consistency (GC) and paste viscosity profiles. Phenotyping for these traits is tedious, time-consuming and expensive. In addition, phenotyping for the starch properties of individuals in a population can only be done on the grain after harvesting, thereby negatively affecting genetic gain. Breeding for cooking and eating quality in rice is thus a major candidate for marker-assisted breeding along with breeding for disease resistance. Major genes for fragrance, AAC and GT have been cloned and the mutations in these genes have been used to develop functional markers for selection. These markers have successfully been applied to improve the cooking and eating qualities of both inbred and hybrid rice in various countries. Additionally, the advent of high-throughput SNP genotyping platforms coupled with the ever-declining cost for genotyping associated with modern sequencing technologies has greatly enhanced opportunities for genomics-assisted breeding for cooking and eating qualities and other important traits in rice.