Article

The genus Anthoxanthum L. (Poaceae: Pooideae) is distributed throughout Europe, Asia, Africa, and the Mediterranean Region is considered its Centre of Diversification. This genus includes annual and perennial species, but the taxonomic status in some of them is doubtful. The purpose of this study was to establish morphological relationships and clarify the taxonomic status ofthe taxa present in the Iberian Peninsula using a statistical approach. Twenty-two wild populations of the different taxa were analized: seven for A. odoratum L., seven for A. arislatum Boiss., six for A. amarum Brot. and two for A. ovatum Lag. A total oftwenty-one characteristics (quantitative and qualitative) were studied in 30 - 35 samples from each population. Statistical analysis was achieved using the program SPSS 10.0. A principal component analysis was employed to deterrnine which ofthe characteristics studied could be used to best characterise each taxon. With the previously selected characteristics the relationships among populations were established using the Phi coefficient for qualitative data and the Manhattan distance for quantitative values. These relationships were represented in two phenograms obtained using UPGMA clustering methods.