Spatiotemporal regulation of leaf angle in rice: The differential regulation of leaf angle throughout the development and across the canopy in rice

The construction of a smart canopy in crops has gained increasing attention in agricultural research due to its role in optimizing light capture, improving photosynthetic efficiency, and enhancing yields. An ideal smart canopy can be achieved by differentially manipulating leaf angles: erect leaves in the upper canopy optimize light distribution, whereas horizontal leaves in the lower canopy maximize light interception, thereby improving photosynthetic efficiency and productivity. In rice, although numerous genes regulating leaf angle and canopy structure have been identified, less attention has been paid to the differential regulation of leaf angle across developmental stages and canopy layers. Here, we review the regulatory roles of leaf angle genes at different developmental stages and canopy levels in rice. Temporal regulatory genes, such as LIC , OsWRKY53 , LC2 , OsMYB7 , NUDX14 , and DS1 , modulate leaf angle at different developmental stages, whereas spatial regulatory genes, including OsSPY , OsAFB2 , OsZHD1 , SLG , and LPA1 , function differentially across canopy layers. Some genes, such as OsCKX3 and RAVL1 , show consistent spatiotemporal effects. However, the majority of leaf angle-associated genes remain insufficiently characterized, and their spatiotemporal regulatory roles are still unclear. To date, no “smart canopy” genes have been identified that progressively modulate leaf angle across both development and canopy layers. Future research should therefore focus on the systematic and comprehensive identification of genes with spatiotemporal regulatory properties, thereby advancing strategies for canopy architecture optimization in rice.