Advances in genetic improvement of wheat photosynthesis for yield enhancement

Wheat (Triticum aestivum L.), one of the world's three major staple crops, continues to face challenges in yield enhancement to ensure food security. Photosynthesis, the most fundamental energy conversion process on Earth, provides the primary source of biomass formation in plants. The first “Green Revolution” in the mid-20th century employed dwarfing genes such as Rht-B1b or Rht-D1b, which reduced plant height by 30-50% and significantly enhanced lodging resistance. Combined with the widespread adoption of fertilizers and pesticides, these advancements led to substantial increases in global wheat yields. However, the yield benefits derived from dwarfing genes have since plateaued, creating a bottleneck for further improvement through height reduction while exacerbating environmental costs of fertilizer-intensive agriculture. With the FAO predicting a 60% increase in global wheat demand by 2050, there is an urgent need for innovative technological strategies to achieve a second leap in productivity. Improving photosynthesis, the core driver of biomass accumulation, offers a promising pathway to overcome current yield limitations. This review synthesizes recent advances in wheat photosynthesis research, focusing on the relationship between photosynthetic carbon assimilation and grain yield. It also identifies key scientific questions, outlines future research directions, and proposes technological strategies for enhancing wheat through photosynthetic optimization. Wheat breeding is now ushering in a second “Green Revolution” era, one powered by the efficient use of solar energy.