Genetic diversity analysis of Mediterranean faba bean (Vicia faba L.) with ISSR markers

Crosses among inbred lines from different Mediterranean-type faba bean gene pools appear promising for the production of high yielding synthetic varieties. The purpose of the present study was to (1) describe the genetic diversity of Greek faba bean local populations, using Inter-Simple Sequence Repeats (ISSRs), and (2) classify the local populations and compare the classification results with those derived from morphological/agronomic data. Four ISSR primers were used on 57 bulked samples of 20 faba bean local populations, five minor-type and 15 Mediterranean-type populations. A total of 192 DNA bands were obtained, of which 190 were polymorphic. Analysis of molecular variance (AMOVA) revealed high levels of within population genetic variation. Based on Nei's standard genetic distances, both cluster analysis using unweighted pair-group method with arithmetic mean (UPGMA) and principal coordinate analysis (PCoA) separated four minor-type populations from the Mediterranean-type populations. The Mediterranean-type populations were further classified into two clusters, with the resultant groups being less diverse than the initial Mediterranean-type gene pool. Mantel test showed that the ISSR markers classification using Nei's genetic distances was statistically different from that derived from morphological/agronomic data using Manhattan distances. Conclusively, the present study supported the suggestion that Mediterranean-type faba beans can be subdivided into at least two different germplasm pools. The groups studied are promising for the production of synthetic varieties.