Comparative genomic analysis demonstrates foxtail millet's tractability as a model for bioenergy grasses, highlighting its small diploid genome and self-compatibility.
Key Points
To evaluate foxtail millet (Setaria italica) as a sequence-driven, tractable model system to accelerate genetic and functional genomic studies in bioenergy grasses.
Evaluated the genome size, ploidy level, and reproductive compatibility of Setaria italica relative to candidate bioenergy grasses including Panicum virgatum, Pennisetum purpureum, and Pennisetum glaucum.
Assessed existing genomic infrastructure, including genetic linkage maps, expressed sequence tag (EST) collections, and whole-genome sequencing initiatives led by the Joint Genome Institute.
Setaria italica has a compact diploid genome (1C = 490 Mb), significantly smaller than pearl millet (1C = 2,352 Mb), napiergrass (1C = 2,254 Mb), and switchgrass (tetraploid 1C = 1,372–1,666 Mb, octaploid 1C = 2,352–3,136 Mb).
Unlike switchgrass, which is largely self-incompatible and polyploid, foxtail millet is self-compatible, inbreeding, and possesses a highly conserved genome structure relative to ancestral grasses.