Disease Resistance Genetics and Genomics in Octoploid Strawberry

Area of Science:

• Genomics
• Plant Pathology
• Agricultural Science

Background:

• Octoploid strawberry (Fragaria ×ananassa) production is threatened by pathogens, necessitating disease resistance gene (R-gene) research.
• Strawberry's complex octoploid genome complicates R-gene identification and introgression in breeding programs.
• Recent advancements in strawberry genomics provide new opportunities for disease resistance studies.

Purpose of the Study:

• To characterize the complete R-gene collection in octoploid strawberry and its diploid ancestors.
• To develop new technological and data resources for strawberry disease resistance research.
• To provide insights into R-gene evolution and natural selection in cultivated strawberry.

Main Methods:

• R-gene collection characterization across octoploid and diploid strawberry genomes.
• Octoploid R-gene transcription profiling, dN/dS analysis, eQTL analysis, and RenSeq analysis.
• Development and validation of an octoploid strawberry capture-probe panel for RenSeq.

Main Results:

• Identified 76 putative R-genes with expression quantitative trait loci (eQTL) in octoploid strawberry fruit.
• Compared R-genes from ancestral diploids, revealing differential inheritance and retention in octoploids.
• Determined the mode and magnitude of natural selection on individual Fragaria ×ananassa R-genes.

Conclusions:

• The study provides unprecedented insight into crop disease resistance genetics.
• Developed resources, including a validated RenSeq probe panel, will benefit the strawberry research community.
• Advances facilitate the exploitation of genetic variation for strawberry cultivar improvement and disease resistance.