Hamblin M.T.,Cornell University |
Close T.J.,University of California at Riverside |
Bhat P.R.,Monsanto Corporation |
Chao S.,U.S. Department of Agriculture |
And 14 more authors.
Crop Science | Year: 2010
Previous studies have shown that there is considerable population structure in cultivated barley (Hordeum vulgare L.), with the strongest structure corresponding to differences in row number and growth habit. U.S. barley breeding programs include six-row and two-row types and winter and spring types in all combinations. To facilitate mapping of complex traits in breeding germplasm, 1816 barley lines from 10 U.S. breeding programs were scored with 1536 sin-gle nucleotide polymorphism (SNP) genotyping assays. The number of SNPs segregating within breeding programs varied from 854 to 1398. Model-based analysis of population structure showed the expected clustering by row type and growth habit; however, there was additional structure, some of which corresponded to the breeding programs. The model that fit the data best had seven populations: three two-row spring, two six-row spring, and two six-row winter. Average linkage disequilibrium (LD) within populations decayed over a distance of 20 to 30 cM, but some populations showed long-range LD suggestive of admixture. Genetic distance (allele-sharing) between populations varied from 0.11 (six-row spring vs. six-row spring) to 0.45 (two-row spring vs. six-row spring). Analyses of pairwise LD revealed that the phase of allelic associations was not well correlated between populations, particularly when their allele-sharing distance was >0.2. These results suggest that pooling divergent barley populations for purposes of association mapping may be inadvisable. © Crop Science Society of America.
Hu G.,Small Grains and Potato Research Facility |
Obert D.E.,Small Grains and Potato Research Facility |
Hang A.,Small Grains and Potato Research Facility |
Burton C.,Small Grains and Potato Research Facility |
And 4 more authors.
Journal of Plant Registrations | Year: 2013
The numerous health benefts associated with the consumption of barley has resulted in U.S. Food and Drug Administration approval for the use of high β-glucan barley in reducing the risk of cardiovascular disease. With the objective of releasing high-value food barley to meet that health claim, 'Julie' (Reg. No. CV-351, PI 665006), a two-rowed, spring, high β-glucan barley (Hordeum vulgare L.) was developed and submitted for release in 2009 by the USDA-ARS, Aberdeen, ID, in cooperation with the University of Idaho Agricultural Experiment Station. Julie is a selection from the cross 10/'Azhul'//'CDC Alamo'. 10 is a selection from composite cross XXXII made by Dr. Tom Ramage (USDA-ARS, retired). Azhul is a six-rowed, high β-glucan cultivar released by the USDA-ARS and the Arizona Agricultural Experiment Station and is the progenitor of most high β-glucan cultivars and germplasm. Azhul was developed by the mutation of line 76-19-7 with diethyl sulfate. Line 76-19-7 has the pedigree CCXXXII/'Arimont'//'Westbar'. CDC Alamo, tested as HB340, has the pedigree SB85750/Azhul. Under dryland and irrigated conditions, the yield and test weight of Julie are greater than those of the currently grown high β-glucan varieties CDC Alamo and Azhul, and Julie has a higher yield of barley β-glucan on a per hectare basis. © Crop Science Society of America.