Transcriptome Analysis Reveals Quality Improvement Mechanisms in Ratoon Rice

Area of Science:

• Agricultural Science
• Plant Physiology
• Molecular Biology

Background:

• Ratoon rice cultivation offers potential for increased yield and grain quality compared to traditional main rice cropping.
• Understanding the molecular mechanisms behind ratoon rice's superior traits is crucial for optimizing cultivation practices.

Purpose of the Study:

• To compare germination, chalkiness, and antioxidant enzyme activities between ratoon and main rice.
• To elucidate the molecular mechanisms, particularly gene expression patterns, underlying the enhanced quality of ratoon rice.

Main Methods:

• Comparative analysis of germination potential, germination rate, chalky grain rate, and chalkiness degree.
• Assay of antioxidant enzyme activities, including superoxide dismutase (SOD) and catalase (CAT).
• Transcriptome analysis to identify differentially expressed genes in ratoon versus main rice.

Main Results:

• Ratoon rice demonstrated significantly higher germination potential and rate, and reduced chalkiness.
• Elevated activities of SOD and CAT were observed in ratoon rice.
• Upregulated expression of genes such as qLTG3-1, OsLOX2, OsSAMDC2, OsSAMDC4, GAD3, peroxidase genes, and OsNCED3 were identified in ratoon rice.

Conclusions:

• Ratoon rice exhibits superior germination and grain quality traits compared to main rice.
• Enhanced germination is linked to upregulated genes involved in germination and stress tolerance.
• Reduced chalkiness is associated with upregulated genes related to high-temperature tolerance, oxidative stress response, and hormone modulation.