An exploitable/attainable yield gap is the difference between actual yield and 80% of modeled potential yield (although, this level depends on price ratios).
• Best farmers’ yields have been shown to be near this exploitable yield level.
Potential yields estimated by crop growth simulation models are not considered to be economically viable because:
• The response of yields to more production inputs decrease as maximum yields are approached.
- Yields above 80% have lower nutrient-use efficiencies.
- Yields at 70–80% are associated with the highest profits.
• It is impossible for a large population of farmers to achieve perfection in crop and soil management.
Different production levels as determined by growth-defining, -limiting, and -reducing factors. Modified from Van Ittersum et al (2013).