Genomic Approaches for Micronutrients Biofortification of Rice, In Plant Micronutrient Use Efficiency

Abstract

Among the micronutrients, iron (Fe) and zinc (Zn) mineral deficiencies are the most common and widespread, afflicting more than half of the human population. Improving both Fe and Zn concentration and their bioavailability in food grains will assure major health benefits. Recent advancements in genomics and genome editing bring new possibilities for targeted research. Next-generation sequencing technologies are allowing the mass sequencing of genomes and transcriptomes, which facilitates the discovery of new genes and regulatory sequences. These can help improve our knowledge of gene function and regulation associated with Fe and Zn metabolism in crops. The key genes can then be used for biofortification of micronutrients through breeding or transgenic approaches. Small noncoding microRNAs (miRNAs) have the potential to provide more effective means to engineer improved Fe and Zn in food crops. Conventional plant breeding can thus be integrated with forward or reverse genomic approaches and high throughput methods to help in rice biofortification. In this chapter, we have described the genomics of micronutirents biofortification in rice. Recent advances in QTL (quantitative traits loci) mapping, noncoding miRNAs, and epigenetics of high Fe and Zn traits in rice have been deliberated. Conventional and recent approaches including transgenic and genome editing for genome engineering to enhance Fe and Zn of rice grain have also been elucidated.