To improve commercial broiler production, Soybean (Glycine max) is a legume that was intended for centuries before J. C to enter the rotation of cultures to fix atmospheric nitrogen. But nowadays, because of its great wealth and many interests, soy cultivation has grown in all parts of the world. The current study conducted in the municipality of Kouandé aims to assess the effect of previous cropping (maize, sorghum, cowpea, soybean, peanut and yam) on the agronomic performance of the Jupiter variety of soybean. For this objective, five (05) squares of 1m² area have been installed in the direction of the diagonals of an envelope. It come out from the results that the previous soybean yielded more flowers (38.83 ± 7.33 flowers/seedlings) followed by the previous maize (25.75 ± 10.32 flowers/seedlings) in contrast to the previousyam, which gave the lowest number of flowers (17.3 ± 71.02 flowers/seedlings). This study showed that the different treatments significantly (P ≤ 0.05) influenced the fruiting time of soybean plants. The early onset of 50% of soybean seed pods was more pronounced with the previous maize (72.33 ± 13.31 Jas), while the number of soybean pod has significantly increased (P ≤ 0.05) with the previous cowpea with the corollary the increase in soybean yields (2400 kg/ha ± 400 kg/ha). To improve the yields of soybeans that benefit from few inputs in its production in the municipality of Kouandé, it is desirable to precede it with cowpea, groundnut or to produce at least twice the soybean on the same area.
