Cowpea, grown for its seeds and haulms in the savannahs of West Africa, is affected by drought. Drought is one of the most damaging constraints to its production with high yield losses. The study conducted at Saria Research Station, in a Fisher block design with two replicates, aimed to identify drought tolerant cowpea varieties. Forty cowpea varieties were screened for drought tolerance in February, under irrigated and non-irrigated regimes. The varieties were evaluated through various variables. Plants grown under non-stressed conditions were watered regularly from sowing to maturity while those under stressed conditions were watered from sowing to flower bud initiation. The varieties showed considerable variability in drought tolerance for the parameters 50% flowering, 95% maturity, 100-seed weight, seed weight, haulm weight and wilting percentage. Water stress had a reducing effect on chlorophyll content, 100-seed weight and seed weight. Stress tolerance index was the best criterion for evaluating genotypes for drought tolerance variability. KVx 402-5-2, 219E and Sarc-1-91-1 showed the best characteristics under both conditions and could be potential parents in the selection of drought tolerant genotypes.

Cowpea, Vigna unguiculata [L] Walp, is one of the most important grain legume grown in all arid and semi-arid regions of Africa. It contributes to reduce malnutrition and poverty and to achieve food security as well. However, cowpea production is hampered by many biotic and abiotic stresses which include viral diseases. Cowpea mosaic caused by CABMV is the main viral disease of cowpea in Africa. This study aims to determine the CABMV transmission rates through seeds describe the reaction of different cowpea genotypes to the virus and identify sources of resistance to serotype D of CABMV. A variation of seed born transmission of CABMV from 3% to 100% was observed for the varieties B301 and Kvu150. Inoculation of cowpea seedling with CABMV results in pods drop leading to yield loss. A negative correlation (r = - 0.33) was observed between date of onset of symptoms and hundred grains weight. The severity of symptoms varied from one cultivar to another. Thus, the best genotypes were those who had better production namely Kvx780-4 SH (28.08 g), Kvx780-3 (21.52 g), Kvx780-9 (20.31 g) and Gourgou (20, 02 g).