Researchers compared growing maize with different legume crops or leaving the land fallow in two different areas in West Africa. They found that adding nitrogen fertilizer increased maize production in one area but not in the other, where phosphorus and sulfur were more important. Some legume crops helped maize grow better than leaving the land fallow, while others did not. The type of legume used affected soil quality and maize yield differently in each area. In one area, growing maize after a certain legume resulted in the highest yield, while in the other area, a different legume was more effective. The study showed that the choice of legume and the specific environment can greatly impact maize production and soil health.