Molecular and Physiological Mechanisms Underlying Submerged Germination in Rice

Area of Science:

• Plant Science
• Agronomy
• Genetics

Background:

• Submergence during germination (SG) poses a significant challenge for direct-seeded rice cultivation.
• Understanding rice's adaptive strategies to SG is crucial for improving crop establishment.

Purpose of the Study:

• To elucidate the physiological and molecular mechanisms underlying rice's response to submergence during germination (SG).
• To identify key genes, signaling pathways, and plant hormone interactions involved in SG tolerance.

Main Methods:

• Physiological analysis of flood-tolerant rice varieties under SG conditions.
• Molecular investigation of gene expression and signaling pathways related to SG.
• Examination of plant hormone crosstalk in SG response.

Main Results:

• Flood-tolerant rice maintains energy supply and cellular homeostasis via enhanced amylase activity, glycolysis, and fermentation.
• Key genes (e.g., SUB1A, OsTPP7, OsGF14h) and pathways involved in hypoxia perception, metabolic reprogramming, and hormone signaling were identified.
• Interactions among ethylene, gibberellin, abscisic acid, and cytokinin are critical for SG.

Conclusions:

• Rice employs complex physiological and molecular mechanisms to adapt to SG.
• Targeting these mechanisms, particularly gene pyramiding and hormone signaling, offers promising breeding strategies for SG-tolerant rice.