Vein density in C4 and C3 leaves: One step closer to understanding the molecular genetic basis

Abstract

Climate change is leading to hotter and drier weather patterns in many regions of the world. Under hot and dry conditions, C4 plants are superior to C3 plants in carbon fixation due to their biochemical and anatomical adaptations that concentrate CO2 at the site of fixation and minimize water loss. A high leaf vein density was a critical step in the origin of C4 from C3 and is crucial to supporting C4 photosynthesis. It has been a long-sought objective to engineer C4 features into C3 crops, such as rice, to increase their adaptability and productivity in a changing climate. A major bottleneck has been a lack of knowledge of the determinants of dense venation in C4 leaves and the difficulty in mimicking them in C3 plants.