Genome-wide association study, linkage mapping and transcriptomic analysis reveal candidate genes associated with...

Area of Science:

• Plant genetics and breeding
• Agricultural science
• Molecular biology

Background:

• Improving nitrogen use efficiency (NUE) in wheat is crucial for increasing crop productivity and reducing environmental impact.
• Genetic and molecular factors underlying wheat NUE require further elucidation.

Purpose of the Study:

• To identify candidate genes associated with nitrogen use efficiency (NUE) in wheat using integrated genetic and transcriptomic approaches.
• To validate quantitative trait loci (QTLs) related to NUE traits in diverse wheat populations.

Main Methods:

• Genome-wide association studies (GWAS) and linkage mapping were performed on two wheat populations (CH and RIL) under varying nitrogen conditions.
• Agronomic traits related to NUE were evaluated across multiple environments.
• Transcriptome analysis was conducted to identify differentially expressed genes within QTL intervals.
• A stable QTL, QYSI1B.2, was validated and refined to a physical region containing the candidate gene TraesCS1B02G308200.

Main Results:

• A total of 836 and 154 QTLs were identified through association and linkage analyses, respectively.
• A stable QTL, QYSI1B.2, was consistently detected and validated across populations and environments.
• TraesCS1B02G308200, encoding a WRKY transcription factor, was identified as a strong candidate gene within the refined QTL region.

Conclusions:

• TraesCS1B02G308200 is a promising candidate gene for enhancing nitrogen use efficiency (NUE) in wheat.
• The study provides a foundation for molecular breeding strategies to improve wheat NUE.
• Integrated genomic and transcriptomic analyses are effective for identifying genes controlling complex agronomic traits.