摘要 : The obligate biotrophic, soil-borne fungus <i>Synchytrium endobioticum</i> causes wart disease of potato (<i>Solanum tuberosum</i>), which is a serious problem for crop production in countries with moderate climates. <i>S. endobio... 展开 The obligate biotrophic, soil-borne fungus <i>Synchytrium endobioticum</i> causes wart disease of potato (<i>Solanum tuberosum</i>), which is a serious problem for crop production in countries with moderate climates. <i>S. endobioticum</i> induces hypertrophic cell divisions in plant host tissues leading to the formation of tumor-like structures. Potato wart is a quarantine disease and chemical control is not possible. From 38 <i>S. endobioticum</i> pathotypes occurring in Europe, pathotypes 1, 2, 6 and 18 are the most relevant. Genetic resistance to wart is available but only few current potato varieties are resistant to all four pathotypes. The phenotypic evaluation of wart resistance is laborious, time-consuming and sometimes ambiguous, which makes breeding for resistance difficult. Molecular markers diagnostic for genes for resistance to <i>S. endobioticum</i> pathotypes 1, 2, 6 and 18 would greatly facilitate the selection of new, resistant cultivars. Two tetraploid half-sib families (266 individuals) segregating for resistance to <i>S. endobioticum</i> pathotypes 1, 2, 6 and 18 were produced by crossing a resistant genotype with two different susceptible ones. The families were scored for five different wart resistance phenotypes. The distribution of mean resistance scores was quantitative in both families. Resistance to pathotypes 2, 6 and 18 was correlated and independent from resistance to pathotype 1. DNA pools were constructed from the most resistant and most susceptible individuals and screened with genome wide simple sequence repeat (SSR), inverted simple sequence region (ISSR) and randomly amplified polymorphic DNA (RAPD) markers. Bulked segregant analysis identified three SSR markers that were linked to wart resistance loci (<i>Sen</i>). <i>Sen1-XI</i> on chromosome XI conferred partial resistance to pathotype 1, <i>Sen18-IX</i> on chromosome IX to pathotype 18 and <i>Sen2/6/18-I</i> on chromosome I to pathotypes 2,6 and 18. Additional genotyping with 191 single nucleotide polymorphism (SNP) markers confirmed the localization of the <i>Sen</i> loci. Thirty-three SNP markers linked to the <i>Sen</i> loci permitted the dissection of <i>Sen</i> alleles that increased or decreased resistance to wart. The alleles were inherited from both the resistant and susceptible parents. 收起