In north of Tunisia, wild cardoon (Cynara cardunculus L. var. sylvestris (Lamk) Fiori) is called “khurshef.” It is consumed mainly for its fleshy stems and leafstalks in some traditional dishes. In some regions, heads were used to prepare cheese. North Tunisian germplasm has been currently damaged by severe genetic erosion, pollution, urbanization, and bad farming practices. In order to preserve this species and to assess morphological relationship between accessions, the present study aims to prospect and to characterize individuals in several areas of the north of Tunisia. Six populations were collected and then 20 individuals per population were evaluated using UPOV (International Union for the Protection of New Varieties of Plant) descriptors related to leaves, leafstalks, and heads. Multivariate analyses were used to elucidate relationship among the studied populations. Principal components analysis revealed more diversity within each population. Cluster study reveals large variability among populations. This analysis allows classifying the germplasm of wild cardoon into five groups. Similarities observed between ecotypes despite their distinctiveness of geographic origin suggest a narrow genetic base. These analyses are very useful for the management and the use of wild cardoon in future breeding programs for Cynara germplasm. 1. Introduction Cynara cardunculus L. (Asteraceae), commonly named “cardoon,” is widespread in the Mediterranean area [1]. It comprises two botanical varieties: C. cardunculus L. var. altilis DC (domestic cardoon) and C. cardunculus L. var. sylvestris (Lamk) Fiori (wild cardoon), considered to be the wild ancestor of globe artichoke [2, 3]. Two gene pools can be distinguished within wild cardoon: the eastern Mediterranean type, mainly distributed in Italy, Greece, and Tunisia, and the western gene pool, diffused in the Iberian Peninsula. It is a nondomesticated robust perennial plant characterized by a rosette of large spiny leaves and branched flowering stems [4]. The main differences between cultivated and wild cardoon are the larger production potential of the former and the distribution of the assimilates between shoot and root, with the wild type investing more carbohydrates in the roots providing more resistance to adverse climatic conditions [5]. The wild cardoon is considered the presumed wild progenitor of the artichoke and the cultivated cardoon [2–4, 6]. These three taxa are fully interfertile [3, 7]. Recent studies have suggested that a high level of differentiation is present in the wild cardoon gene pool and
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