Enhancing Crop Domestication Through Genomic Selection, a Case Study of Intermediate Wheatgrass

Area of Science:

• Agricultural Science
• Plant Breeding
• Genomics

Background:

• Perennial grains offer ecosystem services, but annual grains dominate food production.
• Intermediate wheatgrass (IWG) is being developed as a perennial grain crop.
• Genomic and phenotypic data integration is crucial for multi-site breeding programs.

Purpose of the Study:

• To develop and evaluate genomic selection (GS) models for predicting traits in intermediate wheatgrass.
• To assess the predictive ability of GS models within and across breeding programs and locations.
• To identify key domestication and agronomic traits for IWG improvement.

Main Methods:

• Utilized five cycles of breeding data from two institutions (University of Minnesota and The Land Institute).
• Developed GS models using genotyping-by-sequencing data from 6,199 genets and 23,495 SNP markers.
• Evaluated seven traits: three domestication (free-threshing seed, seed mass, non-shattering) and four agronomic (yield, plant height, etc.).

Main Results:

• GS models showed high predictive ability within breeding cycles (0.11–0.97).
• Across-cycle predictive ability was lower (-0.22–0.76), with domestication traits (0.27–0.75) outperforming agronomic traits (e.g., spike yield -0.22–0.26).
• Non-shattering and free-threshing traits showed predictable improvement across locations and programs.

Conclusions:

• Genomic selection can effectively improve key domestication traits in intermediate wheatgrass across different breeding programs and locations.
• Agronomic traits may require site-specific breeding efforts.
• Synergies in improving domestication traits can accelerate the development of IWG and other perennial crops.