The genetic architecture of leaf vein density and its importance for photosynthesis in maize

For example, higher vein density is observed in angiosperms compared to early land plants, and among angiosperms, recently diverged C4 species typically have the highest values. This adaptation has allowed plant leaves to increase water conductance, transpiration and possibly photosynthesis, although the relationship between vein density and photosynthetic efficiency has not been clearly established.

The genetic architecture of vein density is still not well characterized. Using diverse native varieties of maize, a C4 plant adapted to a wide range of environmental conditions, we show that vein density is variable and plastic. We leverage this plasticity to show that higher densities are correlated with higher photosynthetic rates, but only for small intermediate veins.