The yield gap of major food crops in family agriculture in the tropics: Assessment and analysis through field surveys and modelling

► Grain yields generally fluctuate between 25% and 50% of potential yields. ► Best farmers' yields tend to underestimate the potential yields. ► Simple crop simulation models provide a more accurate estimation of potential yield. ► Soil fertility and weed management are the predominant causes of yield gaps. ► Great potential exists for closing the yield gap by improving agronomic practices.