Integration of AFLP markers into an RFLP-based map of durum wheat

Amplified fragment length polymorphism (AFLP) is a powerful technique which can readily be applied to a wide range of species for mapping purposes. AF LPs were added to a linkage map of durum wheat constructed using restrictio n fragment length polymorphisms (RFLPs). The mapping population included 65 recombinant inbred lines derived from a cross between the durum wheat cult ivar 'Messapia' and accession 'MG4343' of the wild Triticum turgidum ssp. d icoccoides (Korn.). Genomic DNA was digested with MseI(4-cutter) and Sse838 7I(8-cutter). Using a silver-staining protocol, 14 primer combinations reve aled 421 clearly scorable amplicons including 100 polymorphisms. The presen ce of nine pairs of bands linked in repulsion phase with each pair generate d by one primer combination suggested the presence of codominant alleles; s equence analysis of four band pairs confirmed their codominant nature, The integration of 80 AFLP loci extended the map in several telomeric regions, reduced the size of four large gaps present in the previous map, and elimin ated one gap. The new map obtained after the inclusion of the 80 AFLP loci and eight additional RFLP loci spans 2063 cM which represent a 52.6% increm ent compared with the previous map. Compared with the distribution of RFLPs , no significant clustering of AFLP markers was observed.