to determine the effectiveness of the characters used in taxonomic classification, and to help solve taxonomical problems of this large genus at the specific and intraspecific levels by comparing the numerical results with classical taxonomic classification.Materials and Methods: This numerical taxonomic study is based on morphological data that come from a wide range of herbarium material and material collected in the wild. For the analyses, 14 taxa were studied. A range of characteristics of sepal, petal, stamen, silicle, pedicel, septum, stigma, and sinus that are considered to be taxonomically important in the genus were investigated. Morphological data, 90 character states, which belong to 55 characters scored as the binary state for each taxon were used in unweighted pair-group method using arithmetic averages and principle components analyses.Results: L. caespitosum, L. pumilum and L. cartilagineum are recognised at species rank, not subspecies or varieties. L. sativum ssp. sativum and L. sativum ssp. spinescens should be evaluated as two subspecies not synonyms of Lepidium sativum. The most effective characters for the delimitation of the studied taxa are seed length, the habitus of plant, sepal length, septum length, seed wings, the presence of swelling leaf residues on the base of the plant, pedicel length.
Conclusion:Numerical analysis studies based on morphological data on Lepidium taxa growing in Turkey are a useful tool for solving the taxonomic problems of taxa belonging to the genus Lepidium.