Association Mapping and Genomic Selection—Where Does Sorghum Stand?
Sorghum is cultivated as a staple cereal crop in the semi-arid regions of the world. Because of its drought-tolerance ability and high biomass production, it is preferred over other crops for fodder production. In addition to its use as fodder, it is also being used as a bioenergy crop as well as a sugar crop in sweet sorghum. In the last few years, because of advances in genomic techniques, large numbers of molecular markers have been developed in sorghum, which has enabled identification of several quantitative trait loci (QTLs) for various traits using different biparental mapping populations. However, deployment of these identified QTLs in a sorghum improvement program is still lacking as the genetic background in which they were identified does not always represent the breeding program. In recent years the newer approaches of quantitative genetics including association mapping (AM) and genomic selection (GS) has not only facilitated identification of QTLs in diverse genetic backgrounds but also the utilization of all these QTLs in genomic prediction in many crops. This has become possible due to the advancements in the area of computational biology. However, despite the availability of large genomic resources, the progress made in terms of numbers of studies related to AM and GS in sorghum are few, which is in contrast to the situation in other crops such as maize, wheat, and rice. This offers the opportunity for the application of these techniques in a sorghum improvement program. The progress made thus far and the scope available for the use of these two approaches in sorghum is discussed in detail in this chapter.
KeywordsAssociation mapping Linkage disequilibrium GWAS QTL MAS
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