应用RFLP标记研究水稻的广亲和基因

Tagging Genes for Wide Compatibility in Rice via Linkage to RFLP Markers

选用45个分布于10条染色体上的DNA探针,结合4种限制性内切酶,检测了广亲和品种Pecos和测验种南京11、秋光之间DNA限制性片段长度多态性(RFLP),发现其中15个探针能在Pecos、南京11和秋光之间表现多态性。进一步选用14个表现多态性的探针和色素原基因C分析了三交群体(Pecos/南京11∥秋光)中单株结实率的分离,结果表明第6染色体上的RFLP标记RG138、RG64、RG456以及色素原基因C与籼粳杂交亲和性有显著的连锁关系;位于第12染色体上的标记RG81也与三交群体单株结实率显著相关。根据标记与性状的共分离资料,初步绘制了第6染色体上该籼粳杂交亲和性座位的RFLP连锁图。此外,还发现第12染色体上的两个标记RG81和RG323在三交群体中两种基因型的分离比例不符合1:1。

Genes for wide compatibility in rice were analyzed via linkage to RFLP markers. The par- ent varieties were surveyed for restriction fragment length polymorphisms (RFLP) using 45 probes located on ten chromosomes combined with 4 restriction enzymes. 15 probes can detect polymorphisms among the varieties. 14 of 15 polymorphic probes and C gene (chromogen for pigmentation) were selected to further analyze the segregation of spikelet fertility in segregating population of three-way cross (Pecos/Nanjing 11//Akihikari). The results indicate that RFLP markers RG138, RG64, RG456 and morphological marker C gene on chromosome 6 are significantly linked to the locus for wide compatibility. It was also found that another marker RG81 on chromosome 12 was related to spikelet fertility. A prelimi- nary RFLP map of chromosome 6 showing the region of this locus has been constructed. The chromosome region near this locus can be further examined with additional markers to define the precise location of genes for wide compatibility. Tightly linked RFLP markers may facilitate the selection for wide compatibili- ty in rice breeding program. We also observed that the ratios of two genotypes of marker RG81 and RG323 on chromosome 12 in segregating population were 14:41 and 38:17 respectively, being significantly distorted from the expected 1:1 ratio.