Genetic Structure of Miscanthus sinensis from Asia and the United States

To facilitate the domestication and breeding of Miscanthus for use as a bioenergy crop, it will be necessary to develop a diverse germplasm collection from which to map and select traits of interest.  We are using chloroplast microsatellites, GoldenGate SNPs, and RADseq to genetically characterize a collection of M. sinensis.  This collection includes 128 accessions from Japan, 188 from South Korea, 309 from China, and 44 from naturalized populations in the United States, as well as 81 ornamental cultivars.  We found two major groups of chloroplast haplotypes, one of which has a split north-south distribution in Asia.  The region adjacent to the Yangtze River in China has the greatest diversity of chloroplast haplotypes.  SNP markers reveal a large amount of geographic structure to the distribution of genetic diversity across the native range.  Ornamental cultivars and naturalized US populations cluster with M. sinensis from Southern Japan, representing only a fraction of the genetic diversity of the species.  An ideal breeding pool would therefore consist of a broad sample from the native range, rather than relying only on cultivars that are available for purchase in the United States.  In the summer of 2012 our collection was planted at replicate field sites in the United States, Canada, Japan, and Korea.  Our genetic data will be used for association mapping of traits of interest for bioenergy production.