Location: National Clonal Germplasm RepositoryTitle: DNA Markers in Hazelnut: A Progress Report
|MEHLENBACHER, SHAWN - Oregon State University|
Submitted to: International Congress on Hazelnut Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 1/25/2023
Publication Date: N/A
Interpretive Summary: The European hazelnut is the major source of cultivars grown around the world. DNA markers are useful for DNA-informed breeding especially in trees such as hazelnut with a long juvenile period. This study provides an overview of DNA markers and their use in hazelnut from the 1990s to the present. DNA markers are being used to identify hazelnut seedlings that have the 'Gasaway' gene for eastern filbert blight resistance. A DNA fingerprinting set is also being used for cultivar identification. More resources are in development and will be described. These marker resources are useful tools for assisting breeders in developing cultivars that meet the needs of growers and consumers alike.
Technical Abstract: The European hazelnut, Corylus avellana L., is the major source of cultivars grown around the world. DNA markers are useful for marker-assisted selection (MAS), especially in trees such as hazelnut with a long juvenile period. This study provides an overview of PCR- and sequence-based DNA markers and their use in hazelnut. Starting in the last 1990s, Random Amplified Polymorphic DNA (RAPD) markers were used for linkage mapping, and markers associated with self-incompatibility alleles and eastern filbert blight (EFB) resistance were identified. Another dominant PCR-based marker, Amplified Polymorphic Length Polymorphism (AFLP), was also used to identify markers linked to EFB resistance. High Resolution Melting (HRM), Single Characterized Amplified Region (SCAR), and Single-Strand Conformation Polymorphism (SSCP) markers were applied for fine mapping of the EFB resistance region in 'Jefferson'. While RAPDs continue to be routinely used for MAS for resistance to EFB, simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers have replaced them for other applications. Over 900 SSR markers are available in hazelnut where they were used for diversity assessment, cultivar identification, association mapping, core collection establishment, and quantitative trait loci (QTL) mapping. SNPs from reduced representation sequencing were utilized in linkage mapping, and to assess the diversity and domestication of the European hazelnut. A consortium is developing a multi-species nut array of 70,000 SNPs that dedicates at least 20,000 loci for hazelnut, a welcome addition to the markers for use in hazelnut. The DNA marker resources for hazelnut are useful tools for assisting breeders in developing cultivars that meet the needs of growers and consumers alike.