Recent advancements and future perspectives of foxtail millet genomics

Abstract

One of the oldest domesticated crops, foxtail millet (Setaria italica (L.) P. Beauv.) is known for its enormous seed production and ability to grow in unfavourable agro-economic conditions. This understudied diploid panicoid crop plant which performs C4 type of photosynthesis, contains approximately seven folds higher proteins with macro and micro-nutrients as compared to major cereals including rice and wheat. Encompassing a small genome size of ~ 515 Mb, short life cycle, and inbred properties make this orphan crop a potential model system to study abiotic stress tolerance mechanisms adopted by plants. Rich phenotypic variation and the largest available germplasm collection of cultivated and wild species exists for foxtail millet. Release of whole genome sequence in 2012, led to acceleration of functional genomic studies and molecular characterization of Setaria genes conferring stress tolerance. Recent advancements in integrative OMICS and NGS approaches are contributing in functional analysis, understanding complex gene regulatory networks and molecular mechanisms behind its growth and development. Abiotic stress tolerance traits of foxtail millet including drought, salinity, and its survival in nutrient-poor soil can be introduced in popular crop plants by genetic engineering techniques. Stable plant transformation system and precise gene editing in foxtail millet are under optimization which can revolutionize the theme of climate resilient future crops. Overall, foxtail millet has characteristics to serve as an excellent C4 model plant to study evolution, stress physiology and biomass production for bioenergy crops to serve sustainable global food security in near future.