Direct introgression of untapped diversity into elite wheat lines

Area of Science:

• Plant genetics and breeding
• Agricultural science
• Genomics

Background:

• Climate change and population growth threaten global food security.
• Current methods for introducing new genetic traits into crops are slow and inefficient.
• There is a critical need for advanced breeding strategies to utilize natural genetic diversity.

Purpose of the Study:

• To develop and evaluate a novel strategy for introgressing exotic genetic variation into elite crop lines.
• To identify genomic regions and genetic markers associated with desirable agronomic traits.
• To accelerate the integration of diverse genetic resources into modern crop improvement pipelines.

Main Methods:

• A three-way crossing scheme was employed to create 2,867 pre-breeding lines from diverse exotic and elite germplasm.
• Lines were genotyped and phenotyped across four distinct mega-environments.
• Meta-genome-wide association studies, selective sweep analyses, and haplotype-based methods were used to analyze genomic data.

Main Results:

• Genomic analyses revealed selection footprints and identified exotic-specific genetic associations with key agronomic traits.
• Simulations confirmed significant exotic genetic contributions in pre-breeding lines, despite selection biases.
• 95 pre-breeding lines were adopted by national breeding programs, with 7 more advancing to varietal release trials.

Conclusions:

• The strategic three-way crossing approach effectively mobilizes GenBank genetic variation for crop improvement.
• This method significantly accelerates the introgression of beneficial exotic alleles into elite cultivars.
• The developed pre-breeding lines represent a valuable resource for enhancing crop adaptation and yield under challenging environmental conditions.