Pincot Dominique D A, Poorten Thomas J, Hardigan Michael A, Harshman Julia M, Acharya Charlotte B, Cole Glenn S, Gordon Thomas R, Stueven Michelle, Edger Patrick P, Knapp Steven J
Department of Plant Sciences, University of California, Davis, California, 95616.
Department of Plant Pathology, University of California, Davis, California, 95616.
G3 (Bethesda). 2018 May 4;8(5):1817-1828. doi: 10.1534/g3.118.200129.
wilt, a soil-borne disease caused by the fungal pathogen f. sp. , threatens strawberry ( × ) production worldwide. The spread of the pathogen, coupled with disruptive changes in soil fumigation practices, have greatly increased disease pressure and the importance of developing resistant cultivars. While resistant and susceptible cultivars have been reported, a limited number of germplasm accessions have been analyzed, and contradictory conclusions have been reached in earlier studies to elucidate the underlying genetic basis of resistance. Here, we report the discovery of , a dominant gene conferring resistance to wilt in strawberry. The locus was uncovered in a genome-wide association study of 565 historically and commercially important strawberry accessions genotyped with 14,408 SNP markers. Fourteen SNPs in linkage disequilibrium with physically mapped to a 2.3 Mb segment on chromosome 2 in a diploid reference genome. and 11 tightly linked GWAS-significant SNPs mapped to linkage group 2C in octoploid segregating populations. The most significant SNP explained 85% of the phenotypic variability and predicted resistance in 97% of the accessions tested-broad-sense heritability was 0.96. Several disease resistance and defense-related gene homologs, including a small cluster of genes encoding nucleotide-binding leucine-rich-repeat proteins, were identified in the 0.7 Mb genomic segment predicted to harbor DNA variants and candidate genes identified in the present study should facilitate the development of high-throughput genotyping assays for accurately predicting wilt phenotypes and applying marker-assisted selection.
枯萎病是由真菌病原体f. sp.引起的一种土传病害,威胁着全球草莓(×)的生产。病原体的传播,再加上土壤熏蒸措施的颠覆性变化,大大增加了病害压力以及培育抗病品种的重要性。虽然已经报道了抗病和感病品种,但对有限数量的种质资源进行了分析,并且在早期研究中得出了相互矛盾的结论,以阐明抗性的潜在遗传基础。在此,我们报告了在草莓中发现的一个显性基因,该基因赋予对枯萎病的抗性。在对565份具有历史和商业重要性的草莓种质进行全基因组关联研究中发现了该基因座,这些种质用14,408个单核苷酸多态性(SNP)标记进行了基因分型。与该基因紧密连锁不平衡的14个SNP在二倍体参考基因组中物理定位到2号染色体上的一个2.3 Mb片段。在八倍体分离群体中,该基因和11个紧密连锁的全基因组关联研究显著SNP定位到连锁群2C。最显著的SNP解释了85%的表型变异,并在97%的测试种质中预测了抗性——广义遗传力为0.96。在预测含有该基因DNA变异的0.7 Mb基因组片段中鉴定出了几个抗病和防御相关基因同源物,包括一小簇编码核苷酸结合富含亮氨酸重复蛋白的基因,本研究中鉴定的候选基因应有助于开发高通量基因分型检测方法,以准确预测枯萎病表型并应用标记辅助选择。