【作者】 李志英；

【导师】 范在丰；

【作者基本信息】 中国农业大学 ， 植物病理学， 2004， 硕士

【摘要】 本研究选用小麦白粉菌（Blumeria gramini.f.sp tritici）一个普通菌株E17与一个白化的自然突变菌株CPW-1进行杂交并释放子囊孢子获得后代群体，对其白化性状、无毒性进行了遗传分析。利用AFLP分子标记技术对杂交后代进行了分析，初步构建了小麦白粉菌的遗传图谱，同时对色素基因进行了分子标记。 1：对小麦白粉菌CPW-1和E17杂交释放子囊孢子得到的175个后代菌株通过表型进行遗传分析，其白化性状在F₁代分离比符合1:1，表明受一对基因控制。对其中82个后代的无毒性进行了遗传分析。结果表明：对应的抗病基因Pm3b、Pm3f无毒性和毒性分离比为1:1，表明无毒性受1对基因控制；对应的抗病基因Pm13、Pm4b、Pm22的无毒性和毒性呈现3:1的分离比例，表明无毒性受2对显性基因控制，对应的Pm4a的无毒性和毒性呈15:1的分离比例，表明无毒性受3对显性基因控制。 2：在遗传分析的基础上，利用AFLP标记技术进行亲本与后代之间的连锁分析。所筛选的200对随机引物中，有25对引物组合在亲本间存在差异，其中引物对E17M15与白化性状相连锁，其遗传距离为28.2cM。另外有两对引物（E16M19，E21M13）可能与交配型相关，进一步的检测正在进行当中。 3：利用筛选出来的25对在亲本间有明显差异的引物组合对杂交后代进行AFLP分析，13对引物组合共产生39个标记，作图分析结果表明，22个位点分别连锁在7个连锁群上，其中有3个连锁群有3个以上标记，每个连锁群上分别有6个，5个，3个AFLP标记；另外4组只有两个标记，这4个小连锁群的两个标记之间的距离分别为0.7cM、2.9cM、1.4cM、11.0cM和16.1cM，获得的基因组总长度为173.4cM，平均距离为7.9cM。由于用于作图的标记数目较少，有17个标记未发现连锁关系。构建的连锁图有待于进一步饱和。 本文还就AFLP技术进行白粉菌研究的可靠性、分析时应注意的问题等进行了讨论。更多还原

【Abstract】 A normal isolate (E17, pink) of wheat powdery mildew (Blumeria graminis.f.sp.tritici) with a natural mutant (CPW-1,white) were crossed and ascospores released. A population with one hundred and seventy-five progeny individuals was obtained. The number of the progeny isolates for pink and white was 93 and 82, respectively. Genetic analysis for the segregation shows that the ratio of normal progeny to albino ones was approximately 1:1 (2=0.35<2 0.05, 1=3.84), indicating that a single locus confers the albino trait of powdery mildew. 82 selected progenies at random were tested on differential hosts with known resistance genes in greenhouse. The results show that avirulence matching Pm3b and Pm3f is controlled by one gene respectively. Each of avirulences matching Pml3, Pm4b, Pml3 and Pm22 is controlled by two dominant avirulence genes. Avirulence matching Pm (4a) is controlled by three dominant genes.A total of 200 random AFLP primer pairs were used to screen polymorphic DNA fragments and identify the AFLP markers linked to pigment gene between the parents and progenies Result shows that 25 primer pairs can amplify polymorphic DNA fragments. One polymorphic DNA fragment with the length of 700bp was amplified by primer pair E17M15 between offspring of normal and albino isolates. The genetic distance is 28.2cM. Furthermore, two pairs of primers (E16M19, E21M13) may link to genes that control the mating-type trait. The analysis is still on going.13 pairs of primers that selected from random primers were used to make AFLP analysis between parents and 74 progenies. Result shows that 22 markers linked in seven groups. The total distance is 173.4cM, with the average of 7.9cM. The remaining 17 markers were not linked to each other. The reason for this is probably due to the limited number of markers.更多还原