Cowpea (Vigna unguiculata (L.) Walp), a legume with high nutritional value, is widely consumed by West African populations. In Burkina Faso, its yields in rural areas are relatively low due in particular to the perpetuation of old farming methods and especially the low level of soil fertility. The study aims to evaluate the effect of three types of organic manure on the agro-morphological parameters of cowpea. An experimental design in completely randomized blocks with four treatments (T0 = control without organic manure; T1 = cattle dung; T2 = poultry droppings; T3 = sheep dung) and four repetitions was used. The results showed that the weight of 100 seeds did not vary under the influence of the types of fertilizers compared to the control treatment. However, the total number of seeds produced per plant was significantly higher (p˂0.001) under the T2 treatment (102±3 seeds). As for the T1 and T3 treatments, they led to the lowest values ​​of this parameter (respectively 69±4 and 65±4 seeds).

Cowpea, Vigna unguiculata [L.] Walp, is an important seed legume in tropical and sub-tropical regions, particularly in sub-Saharan Africa. Despite its wide adaptation and importance, cowpea productivity is generally very low due to numerous biotic and abiotic constraints. In Burkina Faso, climatic hazards accentuate drought, which limits cowpea production. The aim of this study is to determine the water regime and periods of the year suitable for cold dry-season cultivation of cowpea varieties. To this end, two cowpea varieties (Vigna unguiculata L. Walp.) KN1 and KVX 61.1 were grown in six (06) liter pots in a real environment, during the cold period of the year. Trials were separated by an interval of fifteen (15) days. Each variety was subjected to three watering frequencies. During the study, environmental, growth and agronomic parameters were determined. The study revealed that in cold periods, low temperatures and the application of water regimes reduced most agronomic parameters in both cultivars. Nevertheless, KVX 61.1 produced throughout the study period, while KN1 did not flower when sown from December 09 onwards. The KN1 variety can be sown before December 9 for pod production during the cold off-season, and after that date for its tops, which rich in beneficial elements for livestock are feed. For these two varieties, watering every other day is the best watering regime to ensure good growth and better pod production. These results will serve as an indicator of period and variety for cold dry-season pod and leaf production of these cowpea varieties.