Association Mapping of Kernal Size and Milling Quality in Wheat (Triticum aestivum L.) Cultivars

Association mapping is a method for detection of gene effects based on linkage disequilibrium (LD) that complements QTL analysis for the development of tools for molecular plant breeding. In this study, association mapping was performed on a selected sample of 95 cultivars of soft winter wheat. Population structure was estimated based on 36 unlinked markers. The extent of LD was estimated on chromosomes 2D and part of 5A, relative to the LD observed among unlinked markers. Consistent LD on chromosome 2D was below 1 cM, whereas in the centromeric region of 5A LD extended for approximately 5 cM. Association of 62 loci on chromosomes 2D, 5A and 5B with kernel morphology and milling quality was analyzed through a mixed-effects model, where subpopulation was considered as a random factor and the marker tested was considered as a fixed factor. Permutations were used to adjust the threshold of significance for multiple testing within chromosomes. In agreement with previous QTL analysis, significant markers for kernel size were detected on the three chromosomes tested, and alleles potentially useful for selection were identified. Our results demonstrated that association mapping could complement and enhance previous QTL information for marker-assisted selection.

Key Words: Grain Size, Linkage Disequilibrium, Marker-Assisted Selection, Mixed Model, Population Structure

This article has been cited by other articles:

				S. Myles, J. Peiffer, P. J. Brown, E. S. Ersoz, Z. Zhang, D. E. Costich, and E. S. Buckler Association Mapping: Critical Considerations Shift from Genotyping to Experimental Design PLANT CELL, August 1, 2009; 21(8): 2194 - 2202. [Abstract] [Full Text] [PDF]

				C. H. Sneller, D. E. Mather, and S. Crepieux Analytical Approaches and Population Types for Finding and Utilizing QTL in Complex Plant Populations Crop Sci., March 17, 2009; 49(2): 363 - 380. [Abstract] [Full Text] [PDF]

				S. C. Murray, W. L. Rooney, M. T. Hamblin, S. E. Mitchell, and S. Kresovich Sweet Sorghum Genetic Diversity and Association Mapping for Brix and Height The Plant Genome, March 1, 2009; 2(1): 48 - 62. [Abstract] [Full Text] [PDF]

				J. Yu, Z. Zhang, C. Zhu, D. A. Tabanao, G. Pressoir, M. R. Tuinstra, S. Kresovich, R. J. Todhunter, and E. S. Buckler Simulation Appraisal of the Adequacy of Number of Background Markers for Relationship Estimation in Association Mapping The Plant Genome, March 1, 2009; 2(1): 63 - 77. [Abstract] [Full Text] [PDF]

				E. L. Heffner, M. E. Sorrells, and J.-L. Jannink Genomic Selection for Crop Improvement Crop Sci., January 28, 2009; 49(1): 1 - 12. [Abstract] [Full Text] [PDF]

				C. Zhu, M. Gore, E. S. Buckler, and J. Yu Status and Prospects of Association Mapping in Plants The Plant Genome, July 1, 2008; 1(1): 5 - 20. [Abstract] [Full Text] [PDF]

				B. Stich, J. Mohring, H.-P. Piepho, M. Heckenberger, E. S. Buckler, and A. E. Melchinger Comparison of Mixed-Model Approaches for Association Mapping Genetics, March 1, 2008; 178(3): 1745 - 1754. [Abstract] [Full Text] [PDF]

				B. C.Y Collard and D. J Mackill Marker-assisted selection: an approach for precision plant breeding in the twenty-first century Phil Trans R Soc B, February 12, 2008; 363(1491): 557 - 572. [Abstract] [Full Text] [PDF]

				A. M. Casa, G. Pressoir, P. J. Brown, S. E. Mitchell, W. L. Rooney, M. R. Tuinstra, C. D. Franks, and S. Kresovich Community Resources and Strategies for Association Mapping in Sorghum Crop Sci., January 16, 2008; 48(1): 30 - 40. [Abstract] [Full Text] [PDF]

				J.-B. Veyrieras, L. Camus-Kulandaivelu, B. Gouesnard, D. Manicacci, and A. Charcosset Bridging Genomics and Genetic Diversity: Linkage Disequilibrium Structure and Association Mapping in Maize and Other Cereals Crop Sci., December 18, 2007; 47(Supplement_3): S-60 - S-71. [Abstract] [Full Text] [PDF]

				J. Crossa, J. Burgueno, S. Dreisigacker, M. Vargas, S. A. Herrera-Foessel, M. Lillemo, R. P. Singh, R. Trethowan, M. Warburton, J. Franco, et al. Association Analysis of Historical Bread Wheat Germplasm Using Additive Genetic Covariance of Relatives and Population Structure Genetics, November 1, 2007; 177(3): 1889 - 1913. [Abstract] [Full Text] [PDF]

				L. Skot, J. Humphreys, M. O. Humphreys, D. Thorogood, J. Gallagher, R. Sanderson, I. P. Armstead, and I. D. Thomas Association of Candidate Genes With Flowering Time and Water-Soluble Carbohydrate Content in Lolium perenne (L.) Genetics, September 1, 2007; 177(1): 535 - 547. [Abstract] [Full Text] [PDF]

				M. T. Hamblin, M. G. Salas Fernandez, M. R. Tuinstra, W. L. Rooney, and S. Kresovich Sequence Variation at Candidate Loci in the Starch Metabolism Pathway in Sorghum: Prospects for Linkage Disequilibrium Mapping Crop Sci., July 16, 2007; 47(S2): S-125 - S-134. [Abstract] [Full Text] [PDF]

				S. Chao, W. Zhang, J. Dubcovsky, and M. Sorrells Evaluation of Genetic Diversity and Genome-wide Linkage Disequilibrium among U.S. Wheat (Triticum aestivum L.) Germplasm Representing Different Market Classes Crop Sci., May 31, 2007; 47(3): 1018 - 1030. [Abstract] [Full Text] [PDF]

				J. Ross-Ibarra, P. L. Morrell, and B. S. Gaut Colloquium Papers: Plant domestication, a unique opportunity to identify the genetic basis of adaptation PNAS, May 15, 2007; 104(suppl_1): 8641 - 8648. [Abstract] [Full Text] [PDF]

				J.-L. Jannink Identifying Quantitative Trait Locus by Genetic Background Interactions in Association Studies Genetics, May 1, 2007; 176(1): 553 - 561. [Abstract] [Full Text] [PDF]

				M. R. Miller, J. P. Dunham, A. Amores, W. A. Cresko, and E. A. Johnson Rapid and cost-effective polymorphism identification and genotyping using restriction site associated DNA (RAD) markers Genome Res., February 1, 2007; 17(2): 240 - 248. [Abstract] [Full Text] [PDF]

Online ISSN: 1943-2361  Print ISSN: 0016-6731
Copyright 2009 by the Genetics Society of America
phone: 412-268-1812   fax: 412-268-1813   email: genetics-gsa{at}andrew.cmu.edu