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

2019

English

Introduction Rice is the most important food crop in the world. It is a major source of calories for over a half of the world’s population. Unlike other cereals, rice is mainly eaten as whole grain, thus, cooking and eating quality is extremely important. The cooking and eating quality is measured by the easiness of cooking, texture, springiness, stickiness and chewiness of cooked rice (Champagne et al. 2010). These attributes are controlled by starch physicochemical properties, comprising of apparent amy lose content (AAC), gelatinization temperature (GT), gel consistency (GC) as well as paste viscosity properties, which are popularly called RVA paste viscosity parameters because they are mainly measured using Rapid Visco Analyzer (Bao 2014). These physicochemical properties of starch are measured using tedious and expensive biochemical methods. Assessment of these attributes is further complicated by the lack of discrete phenotypic classes in segregating populations, environmental effects and the triploid nature of the rice plant (He et al. 1999). It can therefore be challenging to breed for these traits in a timely manner. DNA markers could be very useful in selecting for rice genotypes, with the desired cooking and eating qualities. Rice is the first crop plant to have its genome fully sequenced (Yu et al. 2002; Matsumoto et al. 2005). The sequencing of the japonica and indica genomes has helped rice Geneticist, Breeders and Cereal Chemists to identify useful molecular markers for marker-assisted selection for cooking and eating quality traits. In this chapter, we discussed the various cooking and eating quality characteris tics in rice comprising of apparent amylose content (AAC), gelatinization tempera ture (GT), gel consistency (GC), RVA pasting parameters (RVA), aroma and the use of molecular markers to facilitate identifying these traits for their selection in breeding programmes. Some successful examples in the use of DNA markers in breeding for cooking and eating quality in rice have been highlighted. Even though the scope and target of this chapter is MAS for single genes that enable breeders to manipulate key grain quality traits in rice, genomic selection and other more quantitative approaches are mentioned.

Darko, M. A.; Amoako-Andoh, F. O.; Traore, S. E.; Bissah, M. N.; Cobbs, J. N.