NEW APPROACH FOR RICE GENE MAPPING

为了给水稻分子遗传学和育种提供有意义的信息，我们将传统的连锁图谱整合到RFLP连锁图谱中。对24个f2群体进行了遗传标记和抗白叶枯病基因的分离研究。在RFLP连锁图谱上成功定位了形态和生理性状的48个基因，分别为：1号染色体、fs-1、d-18、d-2、rl-2、spl-6和eg， 2号染色体、tri、bl-1、l-chl (t)和spl-2；3号染色体，chl-1, fc-1, st (t)， dl和spl3；4号染色体，d-11, Ph, lg， Xa-1和Xa-2；5号染色体，gl-1, xa-5, d-1, st (t)， spl-7和nl-1；6号染色体，dp-1， spl-4和Cl；7号染色体，g-1, d-6， spl-5和v-11；8号染色体，v-8和糖，9号染色体，I-Bf, dp-2， drop -2和Dn-1；第10染色体，spll -10和pgl；11号染色体，Xa-3, Xa-4, Xa-10， z-2和v-9；本研究对经典连锁图谱和RFLP连锁图谱的定位完全了解，并对经典连锁图谱进行了少许修改。一些RFLP标记与水稻形态和生理性状的基因有密切的联系，可用于水稻选育中的图谱辅助选择，并可作为基因图谱克隆的起点。利用细胞遗传变异，如互反易位、三级三体和主三体，还检查了连锁图谱与染色体的物理关联。在1、3、4、5、7、9和12号染色体上确定了连锁群的方向、标记基因的臂位和着丝粒的推断区域。此外，还开发了重组自交系（RI）作为RFLP/RAPD标记的永久定位群体。利用RI系构建了包含119个RFLP位点和26个rapd位点的地标性连锁图谱。

To furnish significant information to rice molecular genetrics and breeding, we have integrated the conventional linkage map onto the RFLP linkage map. Twenty-four F_2 populations segregating genetic markers and bacterial blight resistance genes were investigated. Fourty-eight genes for the morphological and physiological traits were successfully mapped on RFLP linkage maps as follows : Chromosome 1, fs-1, d-18, d-2, rl-2, spl-6 and eg, Chromosome 2, tri, bl-1, l-chl (t) and spl-2 ; Chromosome 3, chl-1, fc-1, st (t), dl and spl-3 ; Chromosome 4, d-11, Ph, lg, Xa-1 and Xa-2 ; Chromosome 5, gl-1, xa-5, d-1, st (t), spl-7 and nl-1 ; Chromosome 6, dp-1, spl-4 and Cl ; Chromosome 7, g-1, d-6, spl-5 and v-11 ; Chromosome 8, v-8 and sug, Chromosome 9, I-Bf, dp-2, drp-2 and Dn-1 ; Chromosome 10, spl-10 and pgl ; Chromosome 11, Xa-3, Xa-4, Xa-10, z-2 and v-9 ; and Chromosome 12, spl-1 and rl-1 The orientation of the classical linkage map and the RFLP linkage map was completely understood and the classical linkage map was a little revised from this study. Some RFLP markers were found to be closely linked to the genes for the morphological and physiological traits, indicating that they could be useful for map-assisted selection in rice breeding program and for map-based cloning of the genes as starting points.The physical association of the linkage map with chromosomes using cytogenetical variants such as reciprocal translocation, tertiary trisomics and acrotrisomics were also examined. The orientation of linkage groups, the arm location of marker genes and inferred regions of centromeres were decided on chromosomes 1,3,4,5,7,9 and 12.In addition, recombinant inbred (RI) lines were developed as a permanent mapping population for RFLP/RAPD markers. Using the RI lines, landmark linkage map containing 119 RFLP loci and 26RAPD loci were constructed.