空间诱变水稻品系抗稻瘟病遗传及微卫星多态性分析

Blast-Resistance Inheritance of Space-Induced Rice Lines and Their Genomic Polymorphism by Microsatellite Markers

【目的】研究空间诱变水稻品系对稻瘟病的抗性遗传基础,分析其基因组的微卫星多态性。【方法】将3个空间诱变抗病品系H1、H2及H3与普感亲本丽江新团黑谷(LTH)杂交,采用稻瘟病代表性菌株鉴定其F1代和F2代群体,分析诱变品系的抗瘟性遗传基础;同时采用覆盖整个水稻基因组的225对微卫星引物分析诱变品系与原种对照,探讨诱变品系的基因组突变情况。【结果】3个诱变品系对两个代表性菌株的抗性均为显性,其中H1对菌株GD0193和GD3286的抗性均受主效单基因控制,H2和H3对菌株GD3286的抗性均受两对主效基因控制,H2对菌株GD0193的抗性表现出复杂的遗传基础,H3对菌株GD0193的抗性受主效单基因控制;3个诱变品系的微卫星多态性频率各不相同,在不同染色体的突变频率也不相同。【结论】空间诱变可使水稻产生抗病基因,抗病品系的基因组发生了不同程度的变异。

【Objective】To understand the resistance inheritance basis of the space-induced rice lines to blast,and to probe mutants’ genomic DNA polymorphism compared with ground control by microsatellite markers.【Method】Three space-induced lines were crossed with a highly susceptive variety LTH,and their F1 and F2 populations were inoculated by two representative blast isolates with broad pathogenicity to analyze their resistance inheritance basis.Meanwhile the three mutant lines and the ground control were analyzed by 225 rice SSR（simple sequence repeat） primer pairs selected throughout the 12 chromosomes of whole rice genome,to scan the mutagenesis in genome of the mutant lines.【Result】The results indicated that the blast-resistant genes harbored in these mutant lines were dominant.It was demonstrated that the resistance of mutant H1 to isolates GD0193 and GD3286 was controlled by one pair of major genes,respectively,while mutants H2 and H3 were controlled by two pairs of major genes against isolate GD3286 and H2 showed complicated genetic background to isolate GD0193.H3’s resistance to isolate GD0193 was verified to be controlled by major mono-gene.According to the results of SSR analysis,the three mutant lines showed different mutant rates as compared with the ground control,and the mutant rates also varied.【Conclusion】Resistance genes can be induced from rice by space mutation,and different genomic variations were detected in blast-resistant lines.