Yield gap across main crop groups and selected crops
Yield gaps arise from a series of limitations faced by producers, including technical constraints such as limited access to seeds, plant nutrients and pest control capacities, as well as technologies such as mechanization, storage facilities or irrigation. Furthermore, poor access to knowledge and finance, as well as market inefficiencies and policy gaps, play an important role in determining the yield of specific crops.
For each of the 52 crops analysed, GAEZ provides estimates of the attainable yield for given local conditions. GAEZ v5 was used to assess attainable yields and compare them with country-level yield data obtained from FAOSTAT (FAO, 2025b). This analysis was conducted for three crop groups (cereals, roots and tubers, and oil crops) and selected crops, comparing GAEZ v5 data for the historical scenario 2001–2020 with FAOSTAT data averaged over the same period. For a description of the detailed methodology, see the Annex.
At global level, cereal yields averaged slightly above 50 percent of the estimated attainable yields, corresponding to a yield gap of approximately 2 200 kg/ha in absolute terms. In contrast, oil crops performed better, with actual yields corresponding to over 65 percent of their attainable levels and yield gaps of 1 800 kg/ha. Roots and tubers showed actual yields averaging approximately half of the attainable yields, with a substantial yield gap of more than 12 000 kg/ha.
Important variations in cereal production performance exist between countries and between regions (see Figure 18). Africa exhibits the largest gap between attainable and actual yields for cereals, pointing to significant opportunities for improvement: on average, cereal yields in Africa are only one-third of their attainable level, resulting in a gap of approximately 2 800 kg/ha. The Americas and Asia show yield gaps for cereals close to the global average (54 percent). Europe and Oceania have the smallest gaps between attainable and actual yields, reflecting better performance in cereal production: in Europe, average yields are almost three-quarters of their attainable level, with a gap of 1 500 kg/ha, while in Oceania, actual cereal yields are about two-thirds of the attainable level, amounting to a yield gap of 1 600 kg/ha in absolute terms.
Figure 18 Attainable and actual yields, global and regional results for cereals, oil crops, and roots and tubers, average 2001–2020
For oil crops, Africa has the greatest opportunity for improvement compared with the other regions. Actual yields from oil crops in this region are about half of the attainable level, with a yield gap of 2 900 kg/ha. The Americas and Asia show good performance levels, with actual yields reaching more than three-quarters of the attainable level and a yield gap of about 1 100 kg/ha in both regions. Europe and Oceania record similar outcomes, with actual oil crop yields ranging between 62 and 63 percent of their attainable level and yield gaps of 1 300 kg/ha and 2 400 kg/ha, respectively.
Global yields from roots and tubers average about 50 percent of their potential, with variations across regions, ranging from 43 percent in Africa to 56 percent in the Americas and 62–65 percent in Asia and Oceania. Europe achieves more than 80 percent of its attainable level for this crop group, with a yield gap of 5 000 kg/ha.
Figure 19 shows the level of severity of the yield gap for maize, rice and wheat, by country and across regions. The analysis identifies five levels of severity: limited (0–20 percent); moderate (20–40 percent); significant (40–60 percent); severe (60–80 percent); and very severe (80–100 percent). Maize, with the broadest geographical distribution, was analysed in 159 countries. Wheat data covered 124 countries, while rice, due to more specific cultivation requirements, was analysed for 118 countries.
Figure 19 Yield gaps for maize, rice and wheat by severity level, average 2001–2020
SOURCES: Authors’ own elaboration based on FAO & IIASA. 2025. Global Agro-ecological Zoning version 5 (GAEZ v5) Model Documentation. [Cited 13 February 2025]. https://www.fao.org/gaez/en; FAO. 2025. FAOSTAT: Crops and livestock products. [Accessed on 13 February 2025]. https://www.fao.org/faostat/en/#data/QCL. Licence: CC-BY-4.0.
Severe and very severe yield gaps (>60 percent) are common in maize-producing countries. Most African nations face significant yield gaps, with none achieving the best performance category (<20 percent gap). By contrast, Asian and European countries generally exhibit smaller yield gaps for maize.
Wheat also presents widespread large yield gaps, with 50 countries across regions experiencing severe gaps (60–80 percent), signalling that there is strong potential for improvement in this crop. In contrast with maize, also African countries exhibit smaller yield gaps for wheat.
Rice yield gaps exhibit a distinct pattern compared with maize and wheat. Approximately half of all rice-producing countries fall into the limited yield gap category (0–20 percent), showing excellent performance levels. A study by Gerber et al. (2024) confirms that rice yield gaps have narrowed globally over the past decades, with more than 84 percent of rice areas now approaching attainable yields.
Reducing yield gaps
The gap between actual and attainable yields reflects a combination of environmental, socioeconomic and institutional factors. In most cases, productivity is driven by markets, availability and access to finance, inputs, technology and knowledge, which impact farmers’ capacity to efficiently address the main constraints to production.
The availability of soil nutrients is the single most important soil and terrain factor limiting yield, in both prime and good lands and in marginal lands across the regions; it is especially relevant in Africa (see Figure 20). This issue can be addressed through improved soil nutrient management and sustainable mechanization. Associated with limited availability of nutrients is the capacity of soils to retain nutrients, a quality that varies according to the soil’s characteristics. In some parts of tropical regions, soils have poor retention capacity, further complicating nutrient management.
Figure 20 Main soil and terrain constraints in conditions of low-input management in current cropland by region and suitability class
Addressing soil and terrain constraints requires specific solutions. For example, excessive sloping can be addressed by terracing; poor drainage can be improved with artificial drains; and excess of salt can be resolved either through drainage and leaching or through selection of salt-tolerant crops. The feasibility of these solutions will depend on their cost-effectiveness and on the availability of the finance, technologies and knowledge that they require. Chapter 4 gives a detailed presentation of the technological options for increasing yields and reducing the yield gap.
Chapter 5 discusses the enabling environment needed to place farmers in a position to increase productivity and enhance capacity for the planning and management of land resources. Integrated land-use planning involves balancing competing demands for land among different sectors of the economy. FAO is in the process of publishing new ILUP guidelines (FAO, forthcoming). As part of a nine-step process, ILUP includes land suitability analysis, complemented by the selection of sustainable land-use options. A multicriteria analysis supports the decision on the optimum land-use option(s) that enhance production, promote sustainability and assist in achieving multiple benefits with minimum impact. Stakeholder consultation is central to the ILUP process.
