A rapid and robust leaf ablation method to visualize bundle sheath cells and chloroplasts in C₃ and C₄ grasses

Area of Science:

• Plant biology
• Photosynthesis research
• Crop science

Background:

• Engineering the C4 photosynthetic pathway into C3 crops can increase yield.
• This requires enhancing chloroplasts in C3 bundle sheath cells.
• A robust phenotyping method for rice bundle sheath cells is needed.

Purpose of the Study:

• To develop a simple and robust method for phenotyping rice bundle sheath cells.
• To facilitate large-scale testing of chloroplast development regulators in rice.

Main Methods:

• Established a leaf ablation technique for rice.
• Utilized light and confocal laser microscopy for visualization.
• Measured bundle sheath cell dimensions, chloroplast area, and number per cell.

Main Results:

• Leaf ablation allows effective phenotyping of rice bundle sheath cells.
• Bundle sheath width differs significantly between rice (C3) and maize (C4).
• The method detected differences in chloroplast parameters in transgenic rice lines.

Conclusions:

• Leaf ablation provides simple access to bundle sheath cell files in C3 species.
• This method is suitable for assessing bundle sheath cell size and chloroplast parameters.
• Facilitates research towards improving C3 crop photosynthesis.