Figure 2.

Theoretical scenarios for improving grain yield in wheat. (a) Current scenario with GN source‐limited and GW sink‐limited or both co‐limited. Here, grain yield is limited by GN. (b) Optimization of resources for grain number (GN) leads to a trade‐off with the individual grain weight therefore plateauing grain yield through the progress in GN. (c) Removal of source limitation is required for the reproductive and grain filling stages through optimization of flag leaf photosynthesis, spike photosynthesis and WSC remobilization, leading to a reduced trade‐off with the individual grain weight and therefore increase in grain yield.