The successful application of a marker-assisted wheat breeding strategy
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A number of useful marker-trait associations have been reported for wheat. However the number of publications detailing the integrated and pragmatic use of molecular markers in wheat breeding is limited. A previous report by some of these authors showed how marker-assisted selection could increase the genetic gain and economic efficiency of a specific breeding strategy. Here, we present a practical validation of that study. The target of this breeding strategy was to produce wheat lines derived from an elite Australian cultivar ‘Stylet’, with superior dough properties and durable rust resistance donated from ‘Annuello’. Molecular markers were used to screen a BC1F1 population produced from a cross between the recurrent parent ‘Stylet’ and the donor parent ‘Annuello’ for the presence of rust resistance genes Lr34/Yr18 and Lr46/Yr29. Following this, marker-assisted selection was applied to haploid plants, prior to chromosome doubling with cochicine, for the rust resistance genes Lr24/Sr24, Lr34/Yr18, height reducing genes, and for the grain protein genes Glu-D1 and Glu-A3. In general, results from this study agreed with those of the simulation study. Genetic improvement for rust resistance was greatest when marker selection was applied on BC1F1 individuals. Introgression of both the Lr34/Yr18 and Lr46/Yr29 loci into the susceptible recurrent parent background resulted in substantial improvement in leaf rust and stripe rust resistance levels. Selection for favourable glutenin alleles significantly improved dough resistance and dough extensibility. Marker-assisted selection for improved grain yield, through the selection of recurrent parent genome using anonymous markers, only marginally improved grain yield at one of the five sites used for grain yield assessment. In summary, the integration of marker-assisted selection for specific target genes, particularly at the early stages of a breeding programme, is likely to substantially increase genetic improvement in wheat.
KeywordsDough quality Glutenin Marker-assisted selection Plant breeding Rust resistance Triticum aestivum
High molecular weight
Low molecular weight
The authors would like to acknowledge the staff at Australian Grain Technologies, the University of Adelaide and the University of Sydney for there assistance collecting field, end-use quality, molecular marker and rust resistance data. Gratitude is also extended to the Molecular Plant Breeding Cooperative Research Centre and the Grains Research and Development Corporation for their financial assistance. The advice and direction of Prof. P. Langridge is gratefully acknowledged.
- Eglinton J, Coventry S, Chalmers K (2006) Breeding outcomes from molecular genetics. In: Mercer CF (ed) Proceedings of the 13th Australasian Plant Breeding Conference, Christchurch, 2006Google Scholar
- Payne RW, Baird DB, Cherry M, Gilmour AR, Harding SA, Kane AK, Lane PW, Murray DA, Soutar DM, Thompson R, Todd AD, Tunnicliffe Wilson G, Webster R, Welham SJ (2002) GenStat Rlease 6.1 Reference Manual. VSN International, Oxford, UKGoogle Scholar
- Somers DJ, Isaac P (2004) SSRs from the wheat microsatellite consortium. http://wheat.pw.usda.gov/ggpages/SSR/WMC/. Cited 20 Nov 2006Google Scholar