Trends in Fruit Quality Improvement From 15 Years of Selection in the Apple Breeding Program of Washington State University.

Washington State University's apple breeding program (WABP) was initiated in 1994 to select new apple cultivars with improved eating quality, appearance, and storability that are suitable for production in the main growing regions of the state. Fruit quality is phenotyped using various instrumental measures, such as penetrometers (texture), titrator (acidity), and refractometer (soluble solids concentration; SSC), as well as sensory assessment. The selection regime of WABP occurs in three sequential phases: phase one (P1)-single, unreplicated seedlings at one site, phase two (P2)-replicated selections at three geographically diverse sites, and phase three (P3)-highly replicated elite selections at one to two grower sites.

Contributions of Reduced Susceptibility Alleles in Breeding Apple Cultivars with Durable Resistance to Fire Blight.

Breeding apple cultivars with durable genetic resistance is a potential long-term solution to fire blight, a devastating bacterial disease caused by . However, phenotyping resistance/susceptibility to fire blight is challenging due to strain virulence, differential host × strain interactions, quantitative host resistance, environmental influences on disease, and impacts of tree vigor on susceptibility. Inheritance of resistance/susceptibility to fire blight is complex and phenotypic information alone is insufficient to guide breeding decisions targeting resistance.

Fire blight QTL analysis in a multi-family apple population identifies a reduced-susceptibility allele in 'Honeycrisp'.

Breeding apple cultivars with resistance offers a potential solution to fire blight, a damaging bacterial disease caused by Erwinia amylovora. Most resistance alleles at quantitative trait loci (QTLs) were previously characterized in diverse Malus germplasm with poor fruit quality, which reduces breeding utility. This study utilized a pedigree-based QTL analysis approach to elucidate the genetic basis of resistance/susceptibility to fire blight from multiple genetic sources in germplasm relevant to U.

Genetic analysis of stilbenoid profiles in grapevine stems reveals a major mQTL hotspot on chromosome 18 associated with disease-resistance motifs.

Grapevine ( spp.) contains a wealth of phytochemicals that have received considerable attention due to health-promoting properties and biological activities as phytoalexins. To date, the genetic basis of the quantitative variations for these potentially beneficial compounds has been limited.

Uncovering the Genetic Architecture of Seed Weight and Size in Intermediate Wheatgrass through Linkage and Association Mapping.

Intermediate wheatgrass [IWG; (Host) Barkworth & D.R. Dewey subsp.

Elucidation of the 'Honeycrisp' pedigree through haplotype analysis with a multi-family integrated SNP linkage map and a large apple (×) pedigree-connected SNP data set.

The apple () cultivar Honeycrisp has become important economically and as a breeding parent. An earlier study with SSR markers indicated the original recorded pedigree of 'Honeycrisp' was incorrect and 'Keepsake' was identified as one putative parent, the other being unknown. The objective of this study was to verify 'Keepsake' as a parent and identify and genetically describe the unknown parent and its grandparents.