Applying Genomics Resources to Accelerate the Development of Climate Resilient Crops

Climate change and agriculture are correlated with each other in many ways, as climate change is the foremost cause of abiotic and biotic stresses, which adversely affect the growth and development of agricultural crops. Major abiotic stresses directly associated with climate change are drought, heat, salinity, submergence and cold which cause a catastrophic loss in yield of food crops, worldwide. With the clear pieces of evidence of observed changes in climate in the last decades and the growing recognition of the possibility of climate change in the future, an increasing focus on food security and its regional influences have come to the forefront of the scientific community. The development of climate-resilient crop varieties, with improved tolerance to multiple abiotic stresses, becomes essential to ensure global food security under the aberrant climatic conditions. Here in this chapter, we focus on the breeding of major food crops including maize, rice, and wheat. In recent decades, breeding for the development of climate-resilient varieties of these crops has relied primarily on genetic variations present in the crop genome, which has certain limitations. Recent molecular-biotechnological breakthroughs in the understanding of gene functions and access to whole-genome sequences have opened new avenues and facilitated the use of many efficient genomics-assisted breeding strategies such as-marker assisted backcross breeding, marker assisted gene pyramiding, marker-assisted recurrent selection, genomic selection and more recently the genome editing for crop improvement to ensure food security for a growing population under changing climate. In this chapter, we elaborate the progress and prospects of various genomic approaches for developing climate-resilient crop varieties; major emphasis is laid on the literature on the identification of genes, linkage-based QTL mapping, and genome wide association studies-giving user-friendly lists of known genes/QTLs. We also briefly discuss the high-throughput genotyping and phenotyping techniques that are likely to be integral parts of future breeding programs.