Development of a locus-specific, co-dominant SCAR marker for assisted-selection of the Sw-5 (Tospovirus resistance) gene cluster in a wide range of tomato accessions
Development of a locus-specific, co-dominant SCAR marker for assisted-selection of the Sw-5 (Tospovirus resistance) gene cluster in a wide range of tomato accessions
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DOI：
10.1007/s11032-009-9313-8
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发表时间：
2010-01-01
影响因子：
3.1
通讯作者：
Boiteux, Leonardo S.
中科院分区：
文献类型：
--
作者：
Dianese, Erico C.;de Fonseca, Maria Esther N.;Boiteux, Leonardo S.
迄今为止，在番茄中报道的广谱番茄斑萎病毒抗性的最佳水平由Sw-5基因座赋予。该基因座含有至少5个旁系同源物（表示为Sw-5a至Sw-5e），其中Sw-5 b代表实际的抗性基因。在这里，我们评估了一组7个PCR引物对匹配不同序列的基因组区域内跨越Sw-5a和Sw-5 b基因簇。使用具有和不具有Sw-5基因座的番茄等株系进行引物效率评估。一对引物在感病和抗病株系之间产生了单一和共显性的多态性。这些扩增子的序列分析表明，它们是特异性的Sw-5基因座和它们的差异是由于插入/缺失。多态性SCAR扩增子包含功能性Sw-5 b基因启动子区的保守序列，位于其开放阅读框的-31位。该引物对也进行了评价，在田间试验和收集的加入已知是敏感或抗番茄斑萎病毒。在温室/田间条件下的抗性和标记的存在之间几乎完全相关。因此，这对引物是一个非常有用的工具，在标记辅助选择系统在大范围的番茄种质。
The best levels of broad-spectrum Tospovirus resistance reported in tomatoes thus far are conferred by the Sw-5 locus. This locus contains at least five paralogues (denoted Sw-5a through Sw-5e), of which Sw-5b represents the actual resistance gene. Here we evaluated a panel of seven PCR primer pairs matching different sequences within a genomic region spanning the Sw-5a and Sw-5b gene cluster. Primer efficiency evaluation was done employing tomato isolines with and without the Sw-5 locus. One primer pair produced a single and co-dominant polymorphism between susceptible and resistant isolines. Sequence analysis of these amplicons indicated that they were specific for the Sw-5 locus and their differences were due to insertions/deletions. The polymorphic SCAR amplicon encompass a conserved sequence of the promoter region of the functional Sw-5b gene, being located in the position -31 from its open reading frame. This primer pair was also evaluated in field assays and with a collection of accessions known to be either susceptible or resistant to tospoviruses. An almost complete correlation was found between resistance under greenhouse/field conditions and the presence of the marker. Therefore, this primer pair is a very useful tool in marker-assisted selection systems in a large range of tomato accessions.