Population Genomics of Peanut

Abstract

Population genomics envisages studying numerous loci and genome regions simultaneously to understand the roles of evolutionary processes such as mutation, genetic drift, gene flow, and natural selection that influence variation across genomes and populations thereby unfolding the mechanisms of inbreeding and outbreeding depression, adaptive gene flow, population demographic history and the genomic basis of local adaptation and speciation, ecology, evolution, and conservation biology. Since the population genomics also represents the complete description of the genetic variation that exists at the population levels by collating the information generated through various omics like genomics, epigenomics, transcriptomics, proteomics, and metabolomics, it helps delineate the evolution, domestication, adaptation, genotype–phenotype relationships in the populations. Population genomics of peanut (Arachis hypogea), an important oilseed and food crop, is being taken up with the tremendous advancements made in its omics in recent years. The detailed analyses of these omics resources have not only shed light on genome organization and genome features, but also highlighted the peanut origin, spread, domestication, adaptation, and the important genotype–phenotype relationships. Further, the global gene expression atlases for both the subspecies have provided insights into the gene expression landscape. The future developments in peanut population genomics may greatly contribute for understanding the importance of structural polymorphisms in fitness and adaptation, identifying whether the transgenerational epigenetic variations contribute substantially to adaption to changing environments, analyzing gene expression to detect loci under selection and chromosomal islands of adaptive divergence and the alleles associated with various phenotypic traits towards unravelling parallel adaptation. An effort is made in this chapter to review the overall progress towards population genomics in peanut.