Genome sequencing efforts in minor millets: Current knowledge and emerging insights

Abstract

Small millets (or minor millets) include finger millet (Eleusine coracana), foxtail millet (Setaria italica), proso millet (Panicum miliaceum), barnyard millet (Echinochloa crus-galli), kodo millet (Paspalum scrobiculatum), little millet (Panicum sumatrense), teff (Eragrostis tef), fonio (Digitaria exilis), job’s tears (Coix lacryma-jobi), guinea millet (Brachiaria deflexa), and browntop millet (Urochloa ramosa). These millets are highly nutritious and climate-resilient but marginally cultivated for the production and consumption of particular communities. Though called “poor men’s crops,” minor millets possess the potential to ensure food and nutritional security amid the threat of global climate change. Thus, scope exists to improve the agronomic traits of these minor millets for commercial cultivation; however, lack of genomic resources remains a bottleneck to this advancement. Genome sequencing not only provides an opportunity to decode the genes encoded by the genome, but also provides avenue for the development of genomic resources. The success of genome sequencing for resource development and further implementation of these resources have been proven in other crop plants. Among minor millets, genomes of a few species have been sequenced, including finger millet, foxtail millet, proso millet, barnyard millet, teff, fonio, and job’s tears. However, the genomes of kodo millet, little millet, guinea millet, and browntop millet remains to be sequenced. In this context, the chapter summarizes the outcomes of sequencing efforts and the application of genome sequence information in accelerating genomics studies in minor millets. The chapter also enumerates the status of transcriptome sequencing and its application in dissecting the genes underlying important traits.