Development of Marker-Assisted Selection for the Improvement of Freezing Tolerance in Alfalfa
Marker-assisted selection (MAS) accelerates conventional breeding approaches in the improvement of multigenic traits. We used a bulk segregant analysis (BSA) approach to identify genetic polymorphisms closely associated to cold adaptation among populations of alfalfa (Medicago sativa L.) recurrently selected for increased tolerance to freezing (TF). Using bulk DNA samples from cultivar Apica (A-TF0) and populations (A-TF2 and A-TF5) derived from that initial background, we observed both the intensification and the disappearance of several DNA fragments in response to selection pressure. Subsequent assessment of freezing tolerance of individual genotypes confirmed a close relationship between some of these polymorphisms and freezing tolerance. Our results illustrate that the combination of BSA and populations recurrently selected for the improvement of polygenic traits are effective tools to develop MAS applications in alfalfa.
KeywordsFreezing Tolerance Bulk Segregant Analysis Cold Adaptation Restriction Fragment Length Polymorphism Alfalfa Population
Unable to display preview. Download preview PDF.
- Castonguay Y, Cloutier J, Laberge S, Bertrand A, Michaud R (2006) A bulk segregant approach to identify genetic polymorphisms associated with cold tolerance in alfalfa. In: Chen THH, Uemura M, Fujikawa S (eds). Cold hardiness in plants: molecular genetics, cell biology and physiology. CAB International, Wallingford, UK, pp. 88–102Google Scholar
- Clark RM, Schweikert G, Toomajian C, Ossowski S, Zeeler G, Shinn P, Warthmann N, Hu TT, Fu G, Hinds DA, Chen H, Frazer KA, Huson DH, Schölkopf B, Nordborg M, Rätsch G, Ecker JR, Weigel D (2007) Common sequence polymorphisms shaping genetic diversity in Arabidopsis thaliana. Science 317: 338–342CrossRefPubMedGoogle Scholar
- Cravero V, Martín E, Cointry E (2007) Genetic diversity in Cynara cardunculus. determined by sequence-related amplified polymorphism markers J Am Soc Hort Sci 132: 208–212Google Scholar
- Weising K, Nybom H, Wolff K, Kahl G (2005) DNA fingerprinting in plants. Principles, methods, and applications, second edition, CRC Press, Boca Raton, New YorkGoogle Scholar