DNA amplified fragment length polymorphisms in 37 taxa representing 18 species of Lathyrus (Fabaceae) were analyzed by distance methods and the resulting trees were used to reassess the classification of the examined species. The majority of the examined taxa represent section Lathyrus (27 taxa; 12 species), but ten taxa representing three other sections were also included in this study. The analysis of AFLPs demonstrated very clearly a close affinity among taxa of the same species confirming the existence of genetic basis for the taxonomic identity of the examined species. The analysis delimited the studied species in three groups, two of which may be regarded as one super group that comprised the species of section Lathyrus. In this section, L. cicera, L. hirsutus, L. gorgoni and L. sativus formed one group. In the second group of this section L. annuus, L. blepharicarpus and L. hierosolymitanus were distinguished as a subgroup from another subgroup comprised of L. latifolius, L. marmoratus, L. sylvestris and L. tingitanuus. In the third group, L. aphaca of the monotypic section Aphaca was associated with two species of section Linearicarpus, whereas L. shaericus of the latter section was associated with two species of section Clymenum. The AFLP analysis did not support the separation of L. gorgoni in section Gorgania; it is clearly a member of section Lathyrus and is closely associated with L. sativus. AFLP data also indicated that section Linearicarpus seems to be an unnatural group. The relationships of the examined species, as revealed by the analysis of AFLPs, are discussed in the light of their previous classifications based on other lines of evidence.

Key words: AFLP, Fabaceae, Lathyrus