Genome-wide association mapping in elite winter wheat breeding for yield improvement

Area of Science:

• Plant genetics
• Agricultural science
• Genomics

Background:

• Grain yield (GY) is a primary target for wheat breeding programs.
• Understanding the genetic basis of GY is crucial for crop improvement.

Purpose of the Study:

• To identify major genetic determinants of grain yield in elite winter wheat.
• To associate specific genes with grain yield and yield stability.

Main Methods:

• Genome-wide association study (GWAS) on 168 elite winter wheat lines.
• Sequencing using Diversity Array Technology fragments (DArTseq) to generate 19,350 SNP and PAV markers.
• Analysis of marker-trait associations for grain yield and yield stability.

Main Results:

• Fifteen significant genomic regions associated with grain yield variation (7.9–20.3%) and yield stability (13.3%) were identified across ten wheat chromosomes.
• Three genes involved in starch biosynthesis, including two starch synthase genes and one sucrose synthase gene, were significantly associated with grain yield.
• Specific loci (QGy.rut-2B.2, QGy.rut-2D.1, and QGy.rut-3D) were linked to these starch biosynthesis genes.

Conclusions:

• The identified loci and SNP markers are valuable for marker-assisted selection to enhance wheat breeding.
• These genetic resources can be utilized for pyramiding favorable alleles to develop high-yielding wheat varieties.
• The findings contribute to improving the accuracy of genomic selection for grain yield.