Location: Hard Winter Wheat Genetics Research Unit
Title: Construction of dense linkage maps "on the fly" using early generation wheat breeding populations Authors
Submitted to: Molecular Breeding
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 15, 2014
Publication Date: May 22, 2014
Citation: Eckard, J., Gonzales-Hernandez, J., Chao, S., St Amand, P., Bai, G. 2014. Construction of dense linkage maps "on the fly" using early generation wheat breeding populations. Molecular Breeding. DOI:10.1007/s11032-014-0116-1. Interpretive Summary: Construction of genetic maps using DNA markers provide a blueprint for identification of useful genes that can be used in breeding. However, the map construction usually uses experimental populations that can not be directly used in breeding for new cultivars. In this study, we developed a dense and reliable genetic map using extant breeding populations derived from many crosses to eliminate an extra step for experimental population development. Using 565 segregating F1 progenies from 28 four-way cross breeding populations, 3,785 single nucleotide polymorphism (SNP) and 22 simple sequence repeat markers were located in a wheat genetic map. The map showed high rank-order concordance with a SNP consensus map developed from seven mapping populations. Therefore, direct use of breeding populations for mapping can be implemented in wheat breeding programs to speed up the molecular breeding process.
Technical Abstract: In plant species, construction of framework linkage maps to facilitate quantitative trait loci mapping and molecular breeding has been confined to experimental mapping populations. However, development and evaluation of these populations is detached from breeding efforts for cultivar development. In this study, we demonstrate that dense and reliable linkage maps can be constructed using extant breeding populations derived from a large number of crosses, thus eliminating the need for extraneous population development. Using 565 segregating F1 progeny from 28 four-way cross breeding populations, a linkage map of the hexaploid wheat genome consisting of 3,785 single nucleotide polymorphism (SNP) loci and 22 simple sequence repeat loci was developed. Map estimation was facilitated by application of mapping algorithms for general pedigrees implemented in the software package CRI-MAP. The developed linkage maps showed high rank-order concordance with a SNP consensus map developed from seven mapping studies. Therefore, the linkage mapping methodology presented here represents a resource efficient approach for plant breeding programs that enables development of dense linkage maps "on the fly" to support molecular breeding efforts.