Oligonucleotide DNA fingerprinting revealing polymorphism in Phaseolus lunatus L.

Digoxigenated synthetic oligonucleotides complementary tosimple repetitive DNA sequences were used to detect polymorphisms inPhaseolus lunatus L. (Lima bean)genotypes. Twenty two accessions, including wild and cultivatedrepresentatives of the Mesoamerican and Andean gene pools andintermediate forms were included in this study. It could be shownthat five repetitive motifs, namely (AAT)₅,(ATG)₅,(GACA)₄,(GATA)₄,(GGAT)₄, were able to give clear-cutbands when used as probes and to reveal high levels of variation. Thehighest resolving power was revealed by the(AAT)₅ probe, which was able to detect eveninter-individual polymorphisms. Therefore, oligonucleotidefingerprinting has proved to be a useful tool to analyse geneticdiversity in Lima bean. Phylogenetic reconstruction based onJACCARD's similarity index confirmed the existence of two majorgene pools and the presence of a minor group of genetically separatedintermediate genotypes.