Characterization and mapping of Rpi1, a late-blight resistance locus from diploid (1EBN) Mexican Solanum pinnatisectum
Characterization and mapping of Rpi1, a late-blight resistance locus from diploid (1EBN) Mexican Solanum pinnatisectum
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DOI：
10.1007/s004380100490
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发表时间：
2001-08-01
影响因子：
3.1
通讯作者：
Havey, MJ
中科院分区：
文献类型：
--
作者：
Kuhl, JC;Hanneman, RE;Havey, MJ
茄属是一个多样化的属，有超过200种，占据了从美国西南部到智利中部的一系列栖息地。种质评价集中在可以与S.墨西哥二倍体（2n = 2x = 24）茄属物种胚乳平衡数（EBN）为1，但由于其倍性和EBN导致的可交配性差，因此受到较少关注。致病疫霉种群的最新变化增加了对这种真菌的遗传抗性的新来源的需求。我们已经描述了墨西哥2x（1EBN）种S对致病疫霉的抗性。羽状全裂抗病S. pinnatisectum和敏感S. cardiophyllum植株与S. cardiophyllum产生晚疫病抗性分离的家系。用99个RFLP标记构建的二倍体（1EBN）遗传图谱与已发表的马铃薯图谱具有广泛的共线性。在小麦抗晚疫病基因组中发现了一个显性抗晚疫病基因位点（Rpi 1）。pinnatisectum定位于染色体7，这是一个以前与晚疫病抗性无关的区域。用于病害评价的致病疫霉分离株的表征显示，其具有对应于R9抗性位点的无毒基因，表明Rpi 1可能对应于R9。
Solanum is a diverse genus with over 200 species occupying a range of habitats from the Southwestern United States to Central Chile. Germplasm evaluations have focused on species that can be crossed with S. tuberosum, while Mexican diploid (2n = 2x = 24) Solanum species with an Endosperm Balance Number (EBN) of 1 have received less attention because of poor crossability due to their ploidy and EBN. Recent changes in Phytophthora infestans populations have increased the need for new sources of genetic resistance to this fungus. We have characterized resistance to P. infestans in the Mexican 2x (1EBN) species S. pinnatisectum. An interspecific hybrid between resistant S. pinnatisectum and susceptible S. cardiophyllum plants was backcrossed to S. cardiophyllum to generate a family segregating for late-blight resistance. The diploid (1EBN) genetic map generated with 99 RFLP markers revealed extensive synteny with previously published potato maps. A single dominant late-blight resistance locus (Rpi1) from S. pinnatisectum was mapped to chromosome 7, a region previously not associated with late-blight resistance. Characterization of the P. infestans isolate used for disease evaluations revealed that it possessed the avirulence gene corresponding to the R9 resistance locus, indicating that Rpi1 could possibly correspond to R9.