Abstract
Genetic impacts under selective breeding of agricultural crops have been frequently investigated with molecular tools, but inadequate attention has been paid to assess genetic changes under long-term genetic improvement of plant traits. Here we analyzed allelic changes with respect to wheat trait improvement in 78 Canadian hard red spring wheat cultivars released from 1845 to 2004 and screened with 370 mapped SSR markers. The improvements in quality, maturity, yield, disease, stem rust, leaf rust, sawfly resistance, and agronomy were considered. A total of 154 (out of 370) loci with significant allelic changes across 21 chromosomes were detected in the 78 wheat cultivars separated into improved versus non-improved groups for eight traits. The number of significant loci for improving a trait ranged from four for quality to 68 for yield and averaged 35. Many more loci with significant allelic reduction for improving a trait were detected than those with significant allelic increase. Selection for early maturity introduced more alleles, but improving the other traits purged more alleles. Significantly lower numbers of unique alleles were found in the cultivars with improved traits. The distributions of unique allele counts also varied greatly across the 21 chromosomes with respect to trait improvement. Significant SSR variation between two cultivar groups was observed for improvement in seven traits, but not in stem rust. The proportional SSR variation residing between two groups ranged from 0.014 to 0.118. The proportional SSR variations within the improved cultivar groups consistently were much lower than those within the non-improved groups. These findings clearly demonstrate the association between allelic changes and wheat trait improvements and are useful for understanding the genetic modification of the wheat genome by long-term wheat breeding.
References
Allard RW (1998) Genetic changes associated with the evolution of adaptedness in cultivated plants and their wild progenitors. J Hered 79:225–238
Allard RW (1999) Principles of plant breeding, 2nd edn. Wiley, New York
Borlaug N (2007) Sixty-two years of fighting hunger: personal recollections. Euphytica 157:287–297
DePauw RM, Boughton GR, Knott DR (1995) Hard red spring wheat. In: Slinkard AE, Knott DR (eds) Harvest of gold: the history of field crop breeding in Canada. University of Saskatchewan, SK, Canada, pp 5–35
Donini P, Law JR, Koebner RMD, Reeves JC, Cooke RJ (2000) Temporal trends in the diversity of UK wheat. Theor Appl Genet 100:912–917
Duvick DN, Smith JSC, Cooper M (2004) Changes in performance, parentage, and genetic diversity of successful corn hybrids, from 1930 to 2000. In: Smith CW et al (eds) Corn: origin, history, technology and production. Wiley, Hoboken, NJ
Excoffier L, Laval G, Schneider S (2005) Arlequin ver. 3.0: An integrated software package for population genetics data analysis. Evol Bioinform Online 1:47–50
Fu YB (2006) Impact of plant breeding on genetic diversity of agricultural crops: searching for molecular evidence. Plant Genet Resour 4:71–78
Fu YB (2010) FPTEST: a SAS routine for testing differences in allelic count. Mol Ecol Resour 10:389–392
Fu YB, Somers DJ (2009) Genome-wide reduction of genetic diversity in wheat breeding. Crop Sci 49:161–168
Fu YB, Peterson GW, Scoles G, Rossnagel B, Schoen DJ, Richards KW (2003) Allelic diversity changes in 96 Canadian oat cultivars released from 1886 to 2001. Crop Sci 43:1989–1995
Fu YB, Peterson GW, Richards KW, Somers DJ, DePauw RM, Clarke JM (2005) Allelic reduction and genetic shift in the Canadian red hard spring wheat germplasm released from 1886 to 2004. Theor Appl Genet 110:1505–1516
Fu YB, Peterson GW, Yu JK, Gao L, Jia J, Richards KW (2006) Impact of plant breeding on genetic diversity of the Canadian hard red spring wheat germplasm as revealed by EST-derived SSR markers. Theor Appl Genet 112:1239–1247
Fu YB, Peterson GW, McCallum B, Huang L (2010) Population based resequencing analysis of improved wheat germplasm at wheat leaf rust resistance locus Lr21. Theor Appl Genet 121:271–281
Gepts P (2006) Plant genetic resources conservation and utilization: the accomplishments and future of a societal insurance policy. Crop Sci 46:2278–2292
Hao C, Wang L, Zhang X, You G, Dong Y, Jia J, Liu X, Shang X, Liu S, Cao Y (2006) Genetic diversity in Chinese modern wheat varieties revealed by microsatellite markers. Sci China Ser C Life Sci 49:218–226
Hedrick PW (2000) Genetics of populations, 2nd edn. Jones and Bartlett Publishers, Sudbury, MA
Hinze LL, Kresovich S, Nason JD, Lamkey KR (2005) Population genetic diversity in a maize reciprocal recurrent selection program. Crop Sci 45:2435–2442
Huang XQ, Wolf M, Ganal MW, Orford S, Koebner RMD, Roder MS (2007) Did modern plant breeding lead to genetic erosion in European winter wheat varieties? Crop Sci 47:343–349
Hyten DL, Song Q, Zhu Y, Choi I-Y, Nelson RL, Costa JM, Specht JE, Shoemaker RC, Cregan PB (2006) Impacts of genetic bottlenecks on soybean genome diversity. Proc Natl Acad Sci USA 103:16666–16671
Labate JA, Lamkey KR, Lee M, Woodman WL (1999) Temporal changes in allele frequencies in two reciprocally selected maize populations. Theor Appl Genet 99:1166–1178
Li Y, Song Y, Zhou R, Branlard G, Jia J (2009) Detection of QTLs for bread-making quality in wheat using a recombinant inbred line population. Plant Breed 128:235–243
Malysheva-Otto L, Ganal MW, Law JR, Reeves JC, Roder MS (2007) Temporal trends of genetic diversity in European barley cultivars (Hordeum vulgare L.). Mol Breed 20:309–322
McCallum BD, DePauw RM (2008) A review of wheat cultivars grown in the Canadian prairies. Can J Plant Sci 88:649–677
Mikkilineni V, Rocheford TR (2005) RFLP variant frequency differences among Illinois long-term selection protein strains. Plant Breed Rev 24:111–132
Morrison JW (1960) Marquis wheat, a triumph of scientific endeavor. Agric Hist 34:182–188
Neatby KW (1942) New varieties of spring wheat resistant to stem rust in the Canadian West, and their genetical background. Empire J of Experimental Agriculture 10:245–252
Peakall R, Smouse PE (2005) GenAlEx 6: genetic analysis in Excel. Population genetic software for teaching and research. The Australian National University, Canberra, Australia
Robertson A (1960) A theory of limits in artificial selection. Proc Roy Soc London B153:234–249
Rohlf FJ (1997) NTSYS-pc 2.1. Numerical taxonomy and multivariate analysis system. Exeter Software, Setauket, NY, USA
Roussel V, Koenig J, Bechert M, Balfourier F (2004) Molecular diversity in French bread wheat accessions related to temporal trends and breeding programmes. Theor Appl Genet 108:920–930
SAS Institute Inc. (2008) The SAS system for windows V9.2. SAS Institute Incorporated, Cary, NC, USA
Slinkard AE, Knott DR (1995) Harvest of gold: the history of field crop breeding in Canada. University of Saskatchewan, SK, Canada
Somers DJ, Banks T, DePauw R, Fox S, Clarke J, Pozniak C, McCartney C (2007) Genome-wide linkage disequilibrium analysis in breed wheat and durum wheat. Genome 50:557–567
Stuber CW, Moll RH, Goodman MM, Schaffer HE, Weir BS (1980) Allozyme frequency changes associated with selection for increased grain yield in maize (Zea mays L.). Genetics 95:225–236
Sughroue JR, Rocheford TR (1994) Restriction fragment length polymorphism differences among Illinois long-term selection oil strains. Theor Appl Genet 87:916–924
van de Wouw M, van Hintum T, Kik C, van Treuren R, Visser B (2010) Genetic diversity trends in twentieth century crop cultivars: a meta analysis. Theor Appl Genet 120:1241–1252
Walsh B (2005) Population- and quantitative-genetic models of selection limits. Plant Breed Rev 24:177–225
White J, Law JR, MacKay I, Chalmers KJ, Smith JSC, Kilian A, Powell W (2008) The genetic diversity of UK, US, Australian cultivars of Triticum aestivum measured by DArT markers and considered by genome. Theor Appl Genet 116:439–453
Zeng Z-B, Cockerham CC (1990) Long-term response to artificial selection with multiple alleles–study by simulation. Theor Popul Biol 37:254–272
Acknowledgments
The authors would like to thank Ms. Debbie Miranda for her assistance in the management of wheat SSR data and three anonymous reviewers on the early version of the manuscript.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Fu, YB., Somers, D.J. Allelic changes in bread wheat cultivars were associated with long-term wheat trait improvements. Euphytica 179, 209–225 (2011). https://doi.org/10.1007/s10681-010-0235-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10681-010-0235-7