| The availability of genetic diversity in cultivated plants for breeding programs is sometimes limited, especially when there is not accessibility to genepools. Exotic cotton has long been used as a genetic resource to introduce new traits to increase the potential of cotton cultivars. Crosses between wild and cultivated cotton have been done in order to introduce specific traits of interest. Two different populations (F2 and BC1F 2) of a cross between G. darwinii and G. hirsutum (cv. DP 33B) were developed to construct independent linkage maps for further comparison. Amplified Fragment Length Polymorphisms (AFLPs) and Simple Sequence Repeats (SSRs) markers were used to generate polymorphisms for the construction of the linkage maps. Maps were constructed using the mapping software JoinMap 4, with an LOD score between 3.0 and 9.0. Seventeen linkage groups were obtained for the F2 population and 15 for the BC1F2. The map from the F2 population spanned 909 cM with average distance loci of 17.7 cM. Whereas the BC1 F2 spanned 353 cM with average distance loci of 6.44 cM. Mapping comparison was possible because some AFLP and SSR markers were common between populations. Comparison of maps developed from different populations (e.g. F2 and backcross) is valuable in the establishment of differences and similarities, especially map distances and alignments within and between the maps. However it was found that the order marker of loci was not conserved between populations, and the distances of the markers within populations especially in the F2 were longer than expected. On the other hand, the maps generated in this research can be used as frameworks maps for future reference. |
