摘要
以栽培稻品种台中65及其等基因已不育系TISL4为材料，用RFLP和RAPD等技术，对F_1花粉不育基因座S－a定位。通过用RFLP和RAPD方法对亲本间进行多态性分析，发现亲本间的多态性很低，说明经多代回交后，在等基因系基因组中供体亲本的DNA片段所占的比例很小。通过连锁分析，将S－a定位在第1染色体上。S－a与分子标记CDO548、O11—1000、RG146和Y13－500之间的遗传距离分别为6.4cM、6.8cM、7.2cM和11.3cM。S－a基因座上S－a^i／S-a^j等位基因互作使携带S-a^j基因的花粉败育是寻致该F_2群体产生偏态分离的主要原因。
F_1 pollen sterility in cultivated rice (Oryza sativa L.) was found to be caused by at least six loci of F_1 pollen sterility genes. At the S-a locus, one of the six loci for F_1 pollen sterility, the allelic interaction of S-a^i and S-a^j causes the male garnetes carrying S-a^j allele abortive. To map the S-a locus, Taichung 65(T65), a Keng (japonica) variety with S-a^j/S-a^j, its isogenic F_1 sterile line TISL4 with S-a^i/S-a^i from Chin-tsao, a Hsien (indica) variety, and the F_2 population from cross T65×TISL4 were used as materials. The polymorphism between T65 and TISL4 detected by RFLP and RAPD analysis was less than 1%. This result indicated that short segments from Chin-tsao were introgressed into the isogenic F_1 sterile line, since the TISL4 was developed by repeatedly backcrossing for thirteen bines. By linkage analysis of S-a and the marker loci, the S-a locus was mapped on chromosome 1.The genetic distances between S-a and RFLP markers CDO548 and RG146 are 6.4 cM and 7.2cM respectively, and those between S-a and RAPD markers O00-1000 and Y13-500 are 6.8cM and 11.2cM respectively. The mapping of the S-a locus is an important step towards marker-aided selection for overcoming the hybrid sterility in rice.
基金
高等学校博士学科点专项科研基金!930501
国家高技术研究发展计划生物技术项目!BH-01-02-01-04
广东省自然科学基金!960424
美国洛克菲
关键词
杂种不育性
花粉不育基因座
基因定位
水稻
Hybrid sterility, Pollen sterility gene, RFLP, RAPD, Molecular mapping, Oryza sativa L.
