Two dominant loci determine resistance to Phomopsis cane lesions in F 1 families of hybrid grapevines

摘要: Rapid characterization of novel NB-LRR-associated resistance to Phomopsis cane spot on grapevine using high-throughput sampling and low-coverage sequencing for genotyping, locus mapping transcriptome analysis provides insights into genetic a hemibiotrophic fungus. leaf spot, caused by the fungus Diaporthe ampelina (syn = Phomopsis viticola), reduces productivity in grapevines. Host was studied three F1 families derived from crosses involving resistant genotypes ‘Horizon’, Illinois 547-1, Vitis cinerea B9 V. vinifera ‘Chardonnay’. All had progeny with extremely susceptible phenotypes, developing lesions both dormant canes maturing fruit clusters. Segregation symptoms observed under natural levels inoculum field, while phenotypes green shoots were confirmed controlled inoculations greenhouse. High-density maps used localize qualitative loci named Rda1 Rda2 respectively. Co-linearity between reference physical allowed localization 1.5 2.4 Mbp chromosome 7, 19.3 19.6 Mbp 15, which spans cluster five NB-LRR genes. Further dissection this obtained QTL gene expression values 14 h after inoculation across subset ‘Chardonnay’ × V. progeny. This provided evidence association transcript two these genes Rda1, increased among In parent B9, D. characterized up-regulation SA-associated down-regulation ethylene pathways, suggesting an R-gene-mediated response. With dominant effects associated disease-free berries minimal canes, are promising improvement.