Cowpea (Vigna unguiculata (L.) Walp.) is one of the most important grain legumes in sub-Saharian regions. It contributes to man food security by providing a protein-rich diet. However, its production is limited by abiotic stresses such as salinity. This study aims to evaluate the salt tolerance of 15 cowpea cultivars, at germination stage. The seed germination process consisted of sowing them in agarified water (8？g·L？1) supplemented with 6 different concentrations of NaCl (0, 10, 50, 100, 150, and 200？mM). Results highlighted that high salt concentrations drastically reduced germination and significantly delayed the process for all varieties. A cowpea varietal effect towards the salt tolerance was noticed. Genotypes Diongoma, 58-78, and 58-191 were more salt-tolerant cultivars while Mougne and Yacine were more salt-sensitive ones as confirmed in the three groups of the dendrogram. NaCl effects on the early vegetative growth of seedlings were assessed with a tolerant (58-191) and a susceptible (Yacine) cultivar. Morphological (length and dry biomass) and physiological (chlorophyll and proline contents) parameter measurements revealed a negative effect of high (NaCl). However, 58-191 was much more salt tolerant, and the chlorophyll and proline contents were higher than those of Yacine genotype at increasing salt concentrations. 1. Introduction Cowpea (Vigna unguiculata, (L.) Walp.) is a tropical herbaceous leguminous plant belonging to the Fabaceae family. This species is one of the most important grain legume crops in the Sub-saharian regions of Africa because several parts such as dry or fresh seeds (23–32% of protein and 64% of carbohydrate contains), the immature pods, and the leaves are used for human consumption. In addition, dry seeds, pods, and the hay are used for animal feeding during the dry season [1]. For this purpose, cowpea is a valuable source of income for farmers and grain traders in many African countries [2–4]. In Senegal, the economic importance of cowpea is increasing [5] as it is one of the essential crops for rural population diet [6]. Its cultivation is often associated with cereals such as millet, sorghum, and maize [7] due to its ability to establish a nitrogen-fixing symbiosis with Bradyrhizobium and/or mycorrhiza leading to soil fertility improvement [8]. The total cultivated area worldwide is estimated around 9.8 million？ha, with a total production of 3.9 million tons in 2004 [9]. Senegal is a major producer of cowpea in West Africa with an estimated area of 130,730？ha and an average production of 37,648 tons [10]. Salinity
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