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In order to study the salt effect on the wild wheat and durum wheat, three accessions of Aegilops geniculata L. from Ain zana, Zaghouan, and Sbitla and one variety of wheat (Triticum durum L.) have been grown in the INRAT green house and treated with different salt concentrations. The morphological, phenological and yield characters have been measured for each plant and analyzed using SAS software. This study has shown a high degree of variation of these characters mainly related to geographical origin. It was observed also that Sbitla accession was less affected by the imposed salt stress than all the others while Ain zana was the most affected one.

Thirteen Aegilops geniculata Roth (geniculate goat grass) accessions from collection of the North and Central Tunisian (Cap-Bon, Mogodses, Kroumiry and the Dorsal areas) were used to assess its genetic diversity by morphological and Random Amplified Polymorphic DNA (RAPD) data and to evaluate relationship between morphological and RAPD markers. Nineteen morphological traits were analyzed on all accessions using Principal Analysis Component (PCA) and clusters were constrained based on median joining distances. Nineteen arbitrary universal primers were used for the amplification of random DNA sequences and generated 212 bands ranging from 0.5 to 3 kb with 71.27% polymorphism across the 13 accessions. Both RAPD and morphological data classified accessions in two main groups. Both methods were used to compare how morphological traits and RAPD molecular markers described accessions relationship and showed a high degree of variation among analyzed accessions, indicating an important source of genetic diversity that can be used in future breeding programs. Morphological PCA traits and cluster indicated climatic stage. In fact, they grouped Ae. geniculata accessions according to genetic criteria such as earliness and high kernel yield. Comparison of morphological and molecular data using the Mantel test indicated a non significant correlation (r = -0.268). Nevertheless, RAPD and selected morphological characters appear as useful and complementary techniques for evaluation of genetic diversity in Ae. geniculata.

Aegilops geniculata Roth (Poaceae) is a potential source of genetic variation for wheat improvement. In order to distinguish and evaluate different genetic of Aegilops and Triticum using RAPD markers, thirteen Aegilops geniculata populations and three durum wheat varieties (Triticum durum Desf.) were collected from different regions of Tunisia (North and central).

Abstract.-Genetic diversity of three durum wheat cultivars (Triticum durumDesf.) and thirteen Aegilops geniculata Roth accessions belonging to different regions of Tunisia (in North and Central) was evaluated using random amplified polymorphic DNA (RAPD) markers. Nineteen arbitrary universal primers were used for the amplification of random DNA sequences. Data were analysed with the SIMQUAL program using the NTSYS-pc. Phylogenetic diagram was drowning using the UPGMA algorithm. Results indicate an important inter-specific polymorphism between Aegilops and durum wheat. Ae. geniculata accessions revealed a high level of polymorphism (71.27%) than wheat cultivars (39.76%). Two main groups were represented by cluster and principal component analyses. The first group is formed by Ae. geniculata accessions and the second is constituted only by durum wheat cultivars. Consequently, RAPD markers separate clearly Ae. geniculata accessions and durum wheat cultivars.Key words : Aegilops geniculata -Triticum durum -polymorphism -RAPD. Résumé.-La diversité génétique de trois cultivars du blé dur (Triticum durumDesf.) et de treize accessions d'Aegilops geniculata Roth originaires de diffé-rentes régions de la Tunisie (nord et centre) a été évaluée en utilisant la technique RAPD. 19 amorces universelles arbitraires ont été utilisées pour l'amplification aléatoire des séquences de l'ADN. Les données statistiques ont été soumises au programme SIMQUAL du logiciel NTSYS-pc. Le diagramme phylogénétique a été réalisé par le sous-programme d'analyse UPGMA. Les résultats montrent un important polymorphisme interspécifique d'Ae. geniculata et de blé dur. Les accessions d'Ae. geniculata ont révélé un niveau élevé de polymorphisme (71.27%) par rapport à celui du blé (39.76%). Deux principaux groupes sont représentés par le dendrogramme de similarité et l'analyse en composantes principales. Le premier est formé par les accessions d'Ae. geniculata alors que le second n'est formé que par les cultivars du blé dur. En consé-quence, les marqueurs RAPD ont permis de séparer clairement les accessions d'Ae. geniculata et celles de cultivars du blé dur.