Title : Harnessing foxtail millet landraces as a source of novel alleles for yield and nutritional traits
Abstract:
Foxtail millet (Setaria italica L.), a small-grained C4 Panicoid cereal of the Poaceae family, has a compact genome of approximately 515 Mb. It serves as a staple food in the arid and semi-arid regions of Asia and Africa. Despite its exceptional nutritional value and stress tolerance, the rise of Green Revolution crops led to a decline in its cultivation. However, growing concerns about reduced arable land, freshwater scarcity, nutritional needs, and unpredictable environmental stresses have renewed interest in millets as a sustainable solution for global food and nutritional security. Landraces, traditional farmer-maintained varieties, are particularly prized for their adaptability to harsh environments and superior nutritional profiles. Our laboratory studies have uncovered significant genetic polymorphism among landraces compared to elite or released varieties, including variations in drought tolerance and seed micronutrient content. Building on this knowledge, we developed recombinant inbred line (RIL) mapping populations through biparental crosses. True F1 hybrids were selected and advanced to the F7 generation, with genotyping performed via ddRAD sequencing on the HiSeq2500 Next-Generation Sequencing platform. A total of 1,264 highly segregating single nucleotide polymorphism (SNP) markers were confidently mapped to chromosomes, achieving a density of 90–235 SNPs per chromosome and an average marker interval of 4.08 cM. These genomic resources have been leveraged to identify quantitative trait loci (QTLs) associated with agronomic and nutritional traits in foxtail millet. This study underscores the potential of foxtail millet as a resilient crop for enhancing global food security.
