Details

Autor(en) / Beteiligte

• Ecke, Wolfgang
• Clemens, Rosemarie
• Honsdorf, Nora
• Becker, Heiko C.

Titel

Extent and structure of linkage disequilibrium in canola quality winter rapeseed (Brassica napus L.)

Ist Teil von

• Theoretical and applied genetics, 2010-03, Vol.120 (5), p.921-931

Ort / Verlag

Berlin/Heidelberg: Springer-Verlag

Erscheinungsjahr

2010

Link zum Volltext

Quelle

SpringerNature Journals

Beschreibungen/Notizen

• Linkage disequilibrium was investigated in canola quality winter rapeseed to analyze (1) the prospects for whole-genome association analyses and (2) the impact of the recent breeding history of rapeseed on linkage disequilibrium. A total of 845 mapped AFLP markers with allele frequencies ≥0.1 were used for the analysis of linkage disequilibrium in a population of 85 canola quality winter rapeseed genotypes. A low overall level of linkage disequilibrium was found with a mean r 2 of only 0.027 over all 356,590 possible marker pairs. At a significance threshold of P  = 2.8 × 10 −7 , which was derived by a Bonferroni correction from a global α-level of 0.1, only 0.78% of the marker pairs were in significant linkage disequilibrium. Among physically linked marker pairs, the level of linkage disequilibrium was about five times higher with more than 10% of marker pairs in significant linkage disequilibrium. Linkage disequilibrium decayed rapidly with distance between linked markers with high levels of linkage disequilibrium extending only for about 2 cM. Owing to the rapid decay of linkage disequilibrium with distance association analyses in canola quality rapeseed will have a significantly higher resolution than QTL analyses in segregating populations by interval mapping, but much larger number of markers will be necessary to cover the whole genome. A major impact of the recent breeding history of rapeseed on linkage disequilibrium could not be observed.