Abstract: In order to determine the heredity of purple pericarp, the purple pericarp cultivar Xiangxuenuo, developed in Jiangsu Province, and white pericarp cultivar 02428 were used as parents to make reciprocal crosses, and the colour of the seeds of relevant F1, F2, F3 generation were phenotyped. The results indicated that the purple pericarp of Xiangxuenuo was controlled by single dominant nuclear gene, belonging to the typical maternal influence. Purple pericarp in rice was due to a 2 bp deletion in Pb gene on chromosome 4 which encoded a basic helixloophelix protein. A CAPS marker was developed based on the 2 bp deletion, and the CAPS  marker was cosegregated with the colour of pericarp in the F2 population, allowing to identify the homozygous purple pericarp genotype, homozygous white pericarp genotype and heterozygous purple pericarp genotype individuals. The PCR products of 10 rice lines were sequenced. All the purple pericarp rice lines carried GT deletion. It was interesting that the wild rice lines with red pericarp carried the normal allele; therefore we speculated that the purple pericarp was mutated from cultivated rice. Furthermore, one line with purple hull and white pericarp carried pb allele, it showed the complex genetic mechanism in rice pigmentation. In conclusion, the CAPS  marker is a perfect marker for purple pericarp rice breeding and the evolution of Pb gene need further research.

Key words: rice, purple pericarp, delayed inheritance, functional marker

摘要： 以香血糯（紫色果皮）、02428（白色果皮）及以它们为亲本的衍生世代F1、 F2和F3为材料，研究紫色果皮的遗传特征；根据已克隆的紫色果皮Pb与白色果皮pb等位基因第7外显子的差异，设计酶切扩增片段长度多态性标记（CAPS），分析标记基因型；选取10份材料PCR产物进行测序分析。结果表明，以白色果皮02428为母本时，F1的果皮颜色为白色，而以紫色果皮香血糯为母本时，杂交种F1的果皮颜色为紫色；正反交F1植株所结F2种子果皮都为紫色，没有分离；F2植株所结F3种子果皮颜色发生分离，符合3∶1分离比例；CAPS标记分析结果表明紫色果皮基因能被切开，而紫色颖壳基因不能切开，测序结果说明紫色果皮材料相对于白色果皮材料在第7外显子存在GT缺失。因此，水稻紫色果皮是单基因控制的显性遗传，由母体基因型决定，是典型的延迟遗传；紫色果皮与紫色颖壳由不同基因控制；紫色果皮基因的CAPS分子标记可以作为紫米育种的基因功能标记。

关键词: 水稻, 紫色果皮, 延迟遗传, 功能标记