|CABRERA, ANTONIO - The Ohio State University|
|SOUZA, EDWARD - Bayer Corporation|
|GUTTIERI, MARY - University Of Nebraska|
|HOFFSTETTER, AMBER - The Ohio State University|
|SNELLER, CLAY - The Ohio State University|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/1/2014
Publication Date: 5/15/2015
Publication URL: http://handle.nal.usda.gov/10113/61305
Citation: Cabrera, A., Souza, E., Guttieri, M., Sturbaum-Abud, A.K., Hoffstetter, A., Sneller, C. 2015. Genetic diversity, linkage disequilibrium, and genome evolution in a soft winter wheat population. Crop Science. 54:2433-2448.
Interpretive Summary: Soft wheat cultivars were surveyed for diversity using the high-throughput molecular marker techniques of single nucleotide polymorphisms (SNPs) and diversity array technology (DArTs) . Diversity increased in modern cultivars, genotype-similar groups of cultivars were identified and DArTs detected greater diversity than SNPs.
Technical Abstract: Understanding genetic diversity within a crop is fundamental to its efficient exploitation. The advent of new high-throughput marker systems offers the opportunity to expand the scope and depth of our investigation of diversity. Our objectives were to analyze the genetic diversity of two populations of soft winter wheat adapted to the Eastern U.S. The historical population (HP) consisted of 187 lines released or developed from 1808 to 2005. The elite population (EP) consisted of 449 elite modern lines from the Ohio State University breeding program. The HP was genotyped with SNP and DArT markers to create the HPs and HPd data sets while the EP was genotyped with DArT markers to create the EPd data set. Both populations had significant structure with five subgroups in the HP and up to nine in the EP using either SNP or DArT markers. The subgroups could be partly explained by year of release (in HP), class (red versus white wheat) and pedigree (in EP). Diversity appeared to be increasing with time and 11% of the genome exhibited a pronounced linear change over time while evidence of more subtle changes abound. The DArT markers were associated with greater genome changes than the SNP markers. Linkage disequilibrium that produced an r2 of 0.2 or greater extended to about 5 cM in both populations. The extent of LD decay varied widely across the genome. In conclusion, soft winter wheat in the eastern U.S. had a moderate level of structure, appears quite diverse, and may exhibit increasing diversity.