【作者】 杨勇；

【导师】 潘学彪； 朱立煌；

【作者基本信息】 扬州大学 ， 作物遗传育种， 2003， 硕士

【摘要】 本试验以特青／Lemont的F₂代无性系群体共131个系为实验材料，在1999年每个系在田间设一个区组，2000年设两个区组，每个区组8个单株，以牙签嵌入法接种F₂群体，以0-9级病级划分标准调查F₂群体各个单株无性系的病级（见附录），用SSR（simple sequence repeats）的方法对F₂代无性系共131个系进行了全基因组搜索，并结合分群分析法BSA（Bulked Segregation Analysis）构建抗感基因池，应用分子标记在抗感池中筛选阳性标记，然后将阳性标记上群体进一步检测和验证主效QTL的存在。结果如下： 1．亲本间的多态性：共用了350个SSR标记，其中69个多态，多态率为20％左右（3％琼脂糖电泳）。 2．抗水稻纹枯病的主效QTL区间作图分析：对特青／Lemont群体用SSR做全基因组搜索并结合BSA法检测出四个抗纹枯病QTL（qSB7、qSB9、qSB11、qSB12），分别位于第7、第9、第11、第12染色体、其中qSB7、qSB9、qSB12的抗病基因由抗病亲本特青贡献，qSB7两年作图结果均位于RM11-RM346之间，两年分别解释表型变异的28.7％与25.0％。qSB9两年的作图结果分别位于RM245-RM205与RM205-RM201之间，但都在RM205附近，两年分别解释表型变异的16.4％与24.1％，qSB12，1999年的作图结果于RM101-RM519之间，解释表型变异的20.9％。qSB11的抗病基因由感病亲本Lemont贡献，qSB11两年的作图结果均位于RM167-IRM52之间，两年分别解释表型变异的20.4％与12.4％。 3．几个农艺性状的QTL区间作图分析：为了从分子水平验证几个农艺性状与纹枯病有无联系，99年对株高和生育期进行了调查，2000年则又增加了有效穗的调查，通过分子标记在构建的连锁图谱上进行有关基因的定位。在第3染色体的RM143-RM130两年都检测出株高QTL，两年分别解释表型变异的13.5％与16.1％，其由亲本特青提供，在第7染色体的RM214-RM2两年都检测出一个生育期的QTL，两年分别解扬州大学硕士学位论文 释表型变异的15.8%与17.9%，其由亲本Lemont提供。2000年，在第 2染色体的RM 1 54一RM211与RM166一208之间分别检测到株高QTL与 有效穗QTL。分别解释表型变异的11 .4%与12.8%。 从以上结果可以得出水稻抗纹枯病QTL与控制生育期、株高、有效穗这几个农艺性状的QTL在不同染色体或在同一染色体的不同区间。更多还原

【Abstract】 This study was conducted with a clonal F2 population of Teqing/Lemont. The F2 population, including 131 clonal families, was inoculated by short toothpicks incubated with a strain, RH-9 of the fungus. In 1999 each F2 clone was planted into one block with 8 plants for each line, while each was planted into two blocks in 2000. Based on field disease evaluations in two years and SSR(simple sequence repeats)markers distributed in rice genome, we constructed the genetic map combined with BSA(bulked segregation analysis) method. The main results are summarized as below:1) Polymorphisms between two parents: About 350 SSR markers were used to detect the polymorphism and 69 SSR primers showed polymorphism, The ratio of the polymorphism between two parents were 20%.(3%agrose) .2) Interval mapping analysis of resistance to rice sheath blight.In present study, we identified four major quantitative trait loci (QTLs) contributing to sheath blight resistance. These QTLs, qSB-7, qSB-9, qSB-11 and qSB-12, were located on Chromosome7, 9, 11 and 12, respectively. The respective alleles of qSB-7, qSB-9 and qSB-12 were from Teqing, while allele of qSB-11 was from Lemont. qSB-7 which could explain 28.7% or 25% of thetotal phenotypic variation, was located in the interval RM11-RM346 in two years. qSB-9 which could explain 16.4% or 24.1% of the total phenotypic variation, was located in the interval RM245-RM205, RM205-RM201, respectively, in two years. qSB-12 which could explain 20.9% of the total phenotypic variation, was located in the interval RM101-RM519 in one years. qSB-11 which could explain 20.4% or12.4% of the total phenotypic variation, was located in the interval RM167-IRM52 in two years.3) Interval mapping analysis of several agronomic characters.To understand the relationship between sheath blight and severalagronomic characters on the molecular level, In 1999, plant height and heading date were investigated. In 2000, productive panicle was also investigated. In the present study, we identified four major QTLs contributing to the agronomic characters. These QTLs. qE-2, qPH-2, qPH-3 and qHD-7, were located on Chromosome2, 3 and 7, respectively. qPH-3 which could explain 13.5% or 16.1% of the total phenotypic variation, was located in the same interval RM143-RM130 in two years. qHD-7 which could explain 15.8% or 17.9% of the total phenotypic variation, was located in the same interval RM214-RM2 in two years. In 2000, qE-2 and qPH-2 was located in the interval RM154-RM211, RM166-208, respectively. Two QTLS could explain 11.4% and 12.8% of the total phenotypic variation.From the results, we know, there is no linkage between QTLs contributing to the sheath blight and contributing to the agronomic characters.更多还原