摘要：加州野大麦因具有抗病以及抗冻害等多种优良性状，在小麦种质改良过程中，可以作为一个重要种质资源。本实验室前期发现加州野大麦6H染色体对小麦白粉病具有一定的抗性。为了将其加州野大麦的抗白粉病基因准确定位到特定的染色体臂上，本研究过程将首先利用顺序GISH/FISH的分析，从普通小麦中国春与中国春-加州野大麦双二倍体的回交自交BC1F3 后代群体中筛选涉及6H染色体的异染色体系,最后筛选出1株含有纯合的6HS染色体，6株含有杂合的6HS染色体。同时，为了排除背景亲本对白粉病抗性鉴定的影响，我们利用分子标记和顺序GISH/FISH对普通小麦-加州野大麦6H二体异附加系和感白粉病亲本小麦06Y86杂交的F2代进行了分析，筛选出含有纯合的6H染色体植株以及不含有6H的染色体植株。对这些植株以及含有6HS染色体的植株进行了白粉病抗性鉴定，最终将加州野大麦的白粉病抗性基因定位加州野大麦6H染色体的长臂上。

关键词：小麦-加州野大麦的6H染色体系；分子标记；GISH/FISH; 基因定位；白粉病抗性分析；

Identification of alien lines involving 6H chromosome of Hordeum californicum molecular markers and sequential GISH/FISH

Abstract： Hordeum californicum(2n=14, genome HH), one of wild barley, has many useful agronomic traits, such as high resistance to barley yellow dwarf virus and powdery mildew at adult stage and tolerance to freeze injury. In the previous study, we found that 6H chromosome of H.californicum was resistant to powdery mildew at adult stage. In order to locate the resistant gene, T. aestivum L. cv. Chinese spring (CS)-H.californicum amphiploid was crossed to CS，then backcrossed and self-fertilized. Among the BC1F3 progenies，the genetic constitution of backcross progenies were analyzed by sequential C-banding/FISH on root tip cell chromosomes. We found that one plant contained homozygous 6HS chromosome, 6 plants contained one 6HS chromosome. In order to avoid the effect of background on the evaluating resistance, disomic addition line of 6H chromosome was crossed to Nannong 06Y68 and self-fertilized. Among the F2 progenies, we analyzed the constitute of chromosome in 20 plants using the molecular markers specific to 6H chromosome and sequential GISH/FISH. We found that one plant contained homozygous 6H chromosome, 7 plants contained one 6H chromosome, one plant contained one whole chromosome 6H and one short arm of 6H, one plant contained one short arm of 6H. Then we evaluated these plants resistance to powdery mildew. We found that one plant was resistant to powdery mildew if this plant contained 6H chromosome, vice versa. Finally, the gene resistant to powdery mildew was located on the long arm of 6H chromosome.

Key words: Wheat- Hordeum californicum；Molecular marker；GISH/FISH; Gene mapping; Powdery mildew resistance analysis；

目  录

摘要3

关键词3

Abstract3

Key words3

引言（或绪论）3

1材料与方法4

1.1材料 4

1.2方法 4

1.2.1植物根尖体细胞的有丝分裂中期染色体制片4

1.2.2小麦叶片基因组的DNA提取5

1.2.3全基因组的探针标记（缺刻平移法）5

1.2.4荧光原位杂交6

1.2.5制片上的已杂交探针（荧光信号）的洗脱6

1.2.6 PCR反应和其产物的检测7

1.2.7 白粉病抗性鉴定8

2结果与分析9

2.1普通小麦-加州野大麦6H的端体异附加系的选育9

2.2普通小麦-加州野大麦6H的二体异附加系的选育9

2.3对于加州野大麦的6H染色体系的白粉病抗性鉴定11

3讨论 11

致谢11

参考文献12

小麦-加州野大麦6H染色体系的分子细胞遗传学鉴定

引言 小麦，作为世界上最重要的粮食作物之一，面临种植品种逐步单一化的问题，而且小麦的遗传基础日渐狭窄，通过品种间杂交已很难在产量、抗性、适应性等重要性状改良上取得重大突破。在育种工作中，远缘杂交能够在打破种、属间隔离的过程中起到重要的作用，把两个或多个野生物种的优异基因通过染色体工程的手段，导入到栽培品种中，丰富栽培小麦的遗传基础。通过远缘杂交过程，导入异源染色体或其片段，创造异附加系、异代换系以及异易位系是染色体工程育种工作中重要的环节。