A GENETIC-MAP OF POTATO (SOLANUM-TUBEROSUM) INTEGRATING MOLECULAR MARKERS, INCLUDING TRANSPOSONS, AND CLASSICAL MARKERS

A genetic map of potato (Solanum tuberosum L.) integrating molecular m arkers with morphological and isozyme markers was constructed using a backcross population of 67 diploid potato plants. A general method for map construction is described that differs from previous methods empl oyed in potato and other outbreeding plants. First, separate maps for the female and male parents were constructed. The female map contained 132 markers, whereas the male map contained 138 markers. Second, on t he basis of the markers in common the two integrated parental maps wer e combined into one with the computer programme JoinMap. This combined map consisted of 175 molecular markers, 10 morphological markers and 8 isozyme markers. Ninety-two of the molecular markers were derived fr om DNA sequences flanking either T-DNA inserts in potato or reintegrat ed maize transposable elements originating from these T-DNA constructs . Clusters of distorted segregation were found on chromosomes 1, 2, 8 and 11 for the male parent and chromosome 5 for both parents. The tota l length of the combined map is 1120 cM.