Identification of Candidate Genes for Hypoxia Tolerance in Rice by Genome-Wide Association Analysis and Transcriptome...

Area of Science:

• Plant genetics
• Abiotic stress tolerance
• Agricultural science

Background:

• Direct-seeded rice offers reduced labor costs but faces challenges from flooding and hypoxia during germination.
• Hypoxic germination tolerance is critical for the advancement of direct-seeded rice cultivation.

Purpose of the Study:

• To identify genes associated with hypoxic germination tolerance in rice using genome-wide association analysis (GWAS) and transcriptome sequencing.
• To screen and analyze candidate genes for improving rice's ability to germinate under low-oxygen conditions.

Main Methods:

• Genome-wide association analysis (GWAS) was performed on 276 rice germplasms to identify traits correlated with hypoxia tolerance.
• Transcriptome sequencing was conducted on rice varieties with strong and weak hypoxic tolerance under normal and flooding conditions.
• Candidate genes were further screened by integrating GWAS and transcriptome data, followed by functional annotation and haplotype analysis.

Main Results:

• GWAS detected 86 genes related to hypoxic germination tolerance.
• 51 genes were identified through the combined analysis of GWAS and transcriptome sequencing.
• Five significant candidate genes (LOC_Os01g07420, LOC_Os02g01890, LOC_Os03g45720, LOC_Os04g56920, LOC_Os11g41680) were pinpointed based on functional annotation and haplotype analysis.

Conclusions:

• The study identified key candidate genes that can serve as a foundation for future research.
• These findings support the biotechnological improvement of hypoxic germination tolerance in rice.
• Enhanced tolerance can significantly benefit the development and adoption of direct-seeded rice farming.