Analysis of genetic differentiations in radish based on the relationship between make sterile cytoplasma and fertility restorer genes

1. 小稻细胞质雄性不育基因orf138的分布与多态性：应用聚合酶链反应研究了orf138的分布。在十字花科植物中，除莴苣外未见orf138。野生萝卜和日本野萝卜广泛含有该基因，而大多数栽培萝卜缺乏该基因。对于具有oft138的萝卜，确定了该基因的核苷酸序列。在143株植物中发现了7个突变，其中6个为核苷酸变化，1个为39bp的缺失。通过组合突变，发现orf138序列有9个类型，其中2个主要类型在野萝卜和野萝卜中均有分布。这些结果表明，orf138起源于日本野萝卜，并通过日本野萝卜传播。恢复基因的分布与遗传：通过试交，发现雄性不育细胞质的育性恢复基因在野生萝卜中普遍存在。在栽培的萝卜中，大多数日本品种不具有该基因，而欧洲和中国品种具有该基因。这一事实证明了栽培萝卜的多样化起源。在一个欧洲品种、r.r raphanistrum和一个日本野生萝卜中发现的恢复基因都是位于同一位点上的显性基因。恢复基因的分子标记：为了寻找与欧洲品种中发现的恢复基因相关的分子标记，对F2群体进行了雄性不育分离。鉴定出7个RAPD标记，其中一个（OPH11210）与该基因紧密相连。少量RaPD标记转化为SCAR标记，易于稳定检测。

1. Distribution and polymorphisms of the Ogura cytoplasmic male sterile gene, orf138 : The distribution of orf138 was studies using polymerase chain reaction. The orf138 was not observed in other Cruciferous plants than Raphanus. Wild radishes belonging to R.raphanistrum and Japanese wild radish contain this gene widely, while most of cultivated radishes lack it. For radishes having the oft138, nucleotide sequences of the gene were determined. Seven mutations, six were nucleotide changes and one was a deletion of 39bp, were found in 143 plants. By combination of the mutations, 9 types of the orf 138 sequence were found, among them two major types being distributed in both R.raphanistrum and Japanese wild radish. These results clarifies that the orf138 was originated in R.raphanistrum and was transmitted to Japanese wild radish.2. Distribution and inheritance of the restorer gene : By test-crosses, the fertility restorer gene for the male sterile cytoplasm was found to be distributed generally in wild radishes. In cultivated radishes, most of Japanese cultivars do not have the gene, while European and Chinese cultivars possess it. This fact demonstrates diversified origins of cultivated radishes. The restorer genes found in a European cultivar, R.raphanistrum and a Japanese wild radish are all dominant one locating on an identical locus.3. Molecular Marker of the restorer gene : To find molecular markers linked to the restorer gene found in a European cultivar, bulked segregant analysis was applied to a F2 population segregating for the male sterility. Seven RAPD markers were identified, and one of them (OPH11210) was linked tightly to the gene. A few RaPD markers were converted into SCAR markers which are detectable easily and stably.