Abstract: The hybrids were produced by a cross between Brassica oleracea var. capitata and B . oleracea var. alboglabra. A total of 300 random primers were initially screened using two parents , of which 150 showed polymorphism between two parents. The ratio of polymorphism primers is 58. 3 %. 96 F₂ individuals were analyzed using 52 10 bp random primers to select polymorphic , stable and repeatable fragment in preliminary segregation
analysis. Most (95. 8 %) of the segregating fragments followed the expected 3∶1 Mendelian segregation ; 4. 2 % showed significant segregation distortion. This shows that the population is suited for analysis of QTLs. There were two pairs of RAPD markers which showed cosegregation. A genetic linkage map of B. oleracea was constructed based on the segregation of 96 RAPD polymorphic loci in one F₂ population of B. oleracea var. capitata ×B.oleracea var. alboglabra. The genetic markers defined nine linkage groups, covering 555. 7 recombination units.

Key words: Molecular linkage map, RAPD, Brassica oleracea var. capitata