Spatiotemporal Resolved Leaf Angle Establishment Improves Rice Grain Yield via Controlling Population Density

Area of Science:

• Plant Biology
• Crop Science
• Genetics

Background:

• Leaf angle (LA) is a critical determinant of plant architecture and crop yield.
• The lamina joint (LJ) is the primary structure regulating LA, but its developmental mechanisms remain incompletely understood.

Purpose of the Study:

• To elucidate the molecular mechanisms underlying lamina joint (LJ) development and its role in leaf angle (LA) formation.
• To identify key transcription factors (TFs) regulating stage-specific cytological dynamics in the LJ.
• To assess the potential of manipulating these TFs for improving rice architecture and yield.

Main Methods:

• Dissection of five distinct developmental stages of rice LJs.
• Transcriptome (mRNA) and small RNA sequencing across developmental stages.
• Gene co-expression correlation analysis.
• High-throughput promoter analysis.
• Functional characterization of identified transcription factors (TFs) through gene knockout studies.

Main Results:

• Identification of stage-specific mRNA and small RNA profiles correlating with LJ cytological dynamics.
• Discovery of a set of transcription factors (TFs) crucial for stage- and structure-specific LJ development.
• Demonstration that knockout rice mutants lacking key TFs exhibit erect leaves.
• Significant yield enhancement in knockout mutants under dense planting conditions due to maintained tiller number.

Conclusions:

• Cytological dynamics within the lamina joint (LJ) are the primary drivers of leaf angle (LA) determination.
• Identified TFs provide high-resolution insights into LJ development and LA plasticity.
• Targeting these TFs offers a valuable strategy for optimizing rice architecture and increasing yield in dense planting systems.