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 a basic food product which is cultivated in the savannas of west Africa. Its cultivation is confronted to biotic and abiotic constraints. The abiotic constraints are primarily of climatic types (recorded rainfall, temperature). The bad spatio-temporal distribution of recorded rainfall as well as the high temperatures accentuate the drought which blocks the production of cowpea. The aim of the study is to identify the varieties of cowpea that is adapted to the cultivation of dry season, (ii) to determine the suitable hydrous mode and its (their) period(s) in the year favorable to the cultivation of dry season of cowpea. Thus, two varieties of cowpea- KN1 and KVX 61.1 -were cultivated in pots of six (06) liters in real medium, during the hot period of the year. The trials were separated by a fifteen (15) days interval. Each variety was subjected to three hydrous modes from the 14th days after sowing. The environmental, morphological and agronomic parameters were noted during the study. The results revealed that the temperature gradually turned down and the relative humidity and the productivity of KVX 61.1 have gradually increased until the end of the study. . Variety KN1 was illustrated by the absence of flowering. The report biomass root on air biomass evolved according to the temperature. This study reveals that KVX 61.1 sown and sprint led starting from March 26th every two makes it possible to obtain a rather good production of pods.