Breeding effects on durum wheat traits detected using GWAS and haplotype block analysis

Area of Science:

• Plant genetics
• Agricultural science
• Genomics

Background:

• Durum wheat (Triticum turgidum subsp. durum) breeding has evolved, necessitating an understanding of its genetic underpinnings.
• Genomic data advancements offer opportunities to study trait regulation and improve breeding strategies.

Purpose of the Study:

• To assess the impact of modern breeding on durum wheat genetic structures.
• To identify DNA markers for marker-assisted selection and variety registration.

Main Methods:

• Evaluated 123 durum wheat accessions (landraces, ancient, and modern cultivars) across two locations.
• Analyzed 34 agronomic traits, including UPOV descriptors.
• Performed association mapping with 4,241 SNP markers and six multi-locus-GWAS models.

Main Results:

• Identified 28 Quantitative Trait Nucleotides (QTNs) associated with plant morphology and kernel traits.
• Found strong associations for yellow berry (Q.Yb-6A) and flag leaf glaucosity (Q.FGSGls-2B.1).
• Observed increased haploblock diversity in modern cultivars, suggesting breeding program influence.

Conclusions:

• Developed a panel of cost-effective SNP markers linked to UPOV descriptors for variety registration.
• The identified SNP markers can serve as a valuable resource for durum wheat breeding and genetics.