Linkage mapping and QTL analysis in coconut (Cocos nucifera L.)

Different DNA marker types were used to construct linkage maps in coconut ( Cocos nucifera L.; 2n = 32) for the two parents of the cross Malayan Yellow Dwarf (MYD) x Laguna Tall (LAGT). A total of 382 markers was sufficient to generate 16 linkage groups for each parent. The total genome length corres ponded to 2226 cM for the LAGT map and 1266 cM for the MYD map with 4-32 ma rkers per linkage group. Common markers allowed the association of 9 linkag e groups for the two parents MYD and LAGT. QTL analysis for the trail early germination identified six loci. These QTLs correlate with early flowering and yield, representing characters which are important in coconut breeding . The co-segregation of makers with these QTLs provides the first opportuni ty for marker-assisted selection in coconut breeding programmes.