Terakami S, Adachi Y, Iketani H, Sato Y, Sawamura Y, Takada N, Nishitani C, Yamamoto T
Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan.
Genome. 2007 Aug;50(8):735-41. doi: 10.1139/g07-053.
Black spot disease, which is caused by the Japanese pear pathotype of Alternaria alternata (Fr.) Keissler, is one of the most harmful diseases in Japanese pear cultivation. We identified the exact positions and linkage groups (LGs) of the genes for susceptibility to black spot in the Japanese pear (Pyrus pyrifolia Nakai) cultivars 'Osa Nijisseiki' (gene Ani) and 'Nansui' (gene Ana). Segregation of susceptibility and resistance fitted the expected ratio of 1:1 in progeny of 'Nansui' but showed a slight distortion in progeny of 'Osa Nijisseiki'. We mapped the genes for susceptibility to black spot in both populations using a genome scanning approach. The simple sequence repeat (SSR) markers CH04h02 and CH03d02 showed tight linkage to Ani and Ana. Although Ani and Ana are derived from different sources, both genes are located at the top region of LG 11. Information about the positions of the susceptibility genes and the molecular markers linked to them will be useful for marker-assisted selection in pear breeding programs.
黑斑病由链格孢菌日本梨致病型（Alternaria alternata (Fr.) Keissler）引起，是日本梨栽培中危害最大的病害之一。我们确定了日本梨（Pyrus pyrifolia Nakai）品种‘幸水二号’（基因Ani）和‘南翠’（基因Ana）中对黑斑病易感性基因的确切位置和连锁群（LGs）。在‘南翠’后代中，感病性和抗病性的分离符合预期的1:1比例，但在‘幸水二号’后代中出现了轻微的偏分离。我们使用基因组扫描方法在两个群体中对黑斑病易感性基因进行了定位。简单序列重复（SSR）标记CH04h02和CH03d02与Ani和Ana紧密连锁。尽管Ani和Ana来源不同，但两个基因都位于LG 11的顶部区域。易感性基因及其连锁分子标记的位置信息将有助于梨育种计划中的标记辅助选择。
