【作者】 朱振东；

【导师】 贾继增；

【作者基本信息】 中国农业科学院 ， 生物化学与分子生物学， 2003， 博士

【摘要】 小麦白粉病是严重影响小麦生产的重要病害之一。利用抗病品种是防治该病最为经济、有效和环境安全的方法。与抗病基因紧密连锁的分子标记不仅便利抗病基因鉴定和作图，而且可以在育种中进行抗病品系的标记辅助选择。标记辅助选择极大地提高基因累加效率，加速育种进程。小麦野生近缘种属蕴藏着丰富的抗性资源，是小麦抗白粉病基因的重要来源。本研究的主要目的是对从小麦野生近缘种转移到普通小麦中的抗小麦白粉病基因进行鉴定、微卫星标记和作图，并用鉴定的微卫星标记对一些高代品系所携带的抗白粉病基因进行检测。研究结果将为小麦抗白粉病育种提供新的抗病基因，并为这些抗病基因快速、有效和合理的利用奠定基础。 用离体叶段接种方法鉴定了11个四倍体小麦-山羊草双二倍体、波斯小麦PS5、硬粒小麦DR147、5份山羊草、杂交高代材料Am9／莱州953^*2 F₅和（DR147／Ae14）／／莱州953^*2 F₄对20个具有不同毒力白粉菌株的抗谱。通过与含有已知抗病基因品种或品系的对该20个菌株反应模式比较和系谱分析，推测Am9／莱州953^*2 F₅含有Pm4b，波斯小麦PS5含有Pm4b与一个未知抗病基因组合；（DR147／Ae14）／／莱州953^*2 F₄和硬粒小麦DR147含有Pm4a和一个未知抗病基因组合；尾状山羊草Ae14和小伞山羊草Y39含有新的抗白粉病基因。 在由双二倍体Am4和普通小麦百农3217杂交衍生的BC₂F₂群体中鉴定了一个显性抗白粉病基因。该基来源于Am4的四倍体小麦亲本波斯小麦PS5，与微卫星标记Xgwm356的遗传距离为10.2cM。基于标记Xgwm356在小麦染色体上的位置，该基因被定位在小麦染色体2AL。由于该基因与Pm4b一样来源于波斯小麦，并位于Pm4b所在的小麦2AL染色体上相同区域，可能与Pm4b是同一个基因，也可能是与其紧密连锁新基因，因此，暂定名为PmPS5A。 在由双二倍体Am9和普通小麦莱州953杂交衍生的BC₃F₂群体中鉴定了一个显性抗白粉病基因。该基因来源于Am9的四倍体小麦亲本波斯小麦PS5。微卫星标记Xwmc317、Xgwm111、Xgwm382和Xgwm526与其连锁。进一步作图结果表明，该基因位于标记Xwmc317和Xgwm526之间，与两个标记的遗传距离分别为1.1cM和18.1cM，标记Xgwm111和Xgwm382位于标记Xwmc317一侧，与该基因的遗传距离分别为2.2cM和4.0cM。基于连锁标记在小麦染色体上的位置，该基因被定位在小麦染色体2BL上。由于该基因不同于定位在小麦2B染色体上的已知抗白粉病基因Pm6和Pm26，应该是一个新的抗病基因，暂定名为PmPS5B，建议定名为Pm32。 在由双二倍体Am9与普通小麦莱州953杂交衍生的BC₃F₅分离群体中，鉴定了一个新的抗白粉病基因。微卫星标记Xgwm296、Xgwm257和Xgwm319与该基因共分离。Xgwm257和Xgwm319为共显性标记，Xgwm29显性标记，3个抗性相关的标记在小伞山羊草Y39上特异扩增，表明该基因来源于Am9的山羊草亲本小伞山羊草Y39，为显性。微卫星标记Xgwm210、Xgwm388a、Xgwm388b和Xgwm526为感病性相关标记，在互斥相与抗病基因连锁。基于连锁标记在小麦染色体上的位置和遗传作图结果，我们认为在本研究群体中小麦2B染色体被小伞山羊草2U染色体代换，但2U染色体和2B染色体间也发生低频率的重组。根据交换株的微卫星分析结果，推测该基因位于小伞山羊草染色体2US上。由于该基因是第一个从小伞山羊草向普通小麦中转移的抗白粉病基因，应该是一个新的抗白粉病基因，暂定名为PmY39，建议定名为Pm33。 在由高大山羊草Y150和莱丹D％3杂交衍生的＊Qn群体中鉴定了一个显性抗小麦白粉病基因。微卫星标记Xu m32工Xwmc382和Xwmc397在转入的高大山羊草染色体上特性扩增，与抗病基因的遗传距离分别为2．6cM、3．3cM和8刀cM。另外，微卫星标记 Xum46g、XpW30js和K一加98为感病性相关标记，在互斥相与抗病基因的连锁距离均为2石CM。综合与抗病基因连锁的抗性相关标记和感病性标记，构建了该基因和与其连锁标记的遗传连锁图。基于连锁的微卫星标记在小麦染色体的位置和作图结果，在BCZFS群体中小麦6D染色体可能被高大山羊草6S染色体代换，但6S染色体和6D染色体间也发生低频率的小片段易位。根据交换株的微卫星标记分析结果，推测该基因位于高大山羊草6S染色体长臂末端。该基因为新的抗白粉病基因，暂定名为PmyI50，建议定名为Pm34。 在由硬粒小麦DR147－尾状山羊草Ael4合成的双二借体与普通小麦品种莱州953杂交衍生的＊Q比群体中鉴定了一个显性抗小麦白粉病基因。该基因来源于硬粒小麦DR147。微卫星标记地rrm．xll和拒；mtn－H与该基因紧密连锁，遗传距离分别为5．9 CM和 4．gCM。根据己发表的小麦微卫星图谱和对中国春缺－四体DNA扩增结果，该基因被定位在小麦ZA染色体的长臂末端。由于该基因位于ZAL染色体上邻近基因Pm4位点的区域，可能是与Pm4位点连锁的新基因，或是Pm4位点的一个等位基因。该基因暂定名为PmDR147。 利用分别与抗小麦白粉病基因 PmPSJA、PmPSM和 PmY39连锁的微卫星标记对由波斯小麦PSS和小伞山羊草Y39衍生抗白粉病的高代品系进行抗白粉病基因检测。在检测的88个抗病品系中，有26个品系检测到PmPAN，38?更多还原

【Abstract】 Powdery mildew, caused by Erysiphe graminis f. sp. tritici, is one of the devastating diseases of wheat (Triticum aestivum L. em Thell.). The use of resistant cultivars is the most economical, effective and environmentally safe way to control this disease. Molecular markers tightly linked to resistance genes not only facilitates the identification and mapping of resistance genes, but also can be used for markers-assisted selection (MAS) of resistant lines in breeding programs. MAS greatly enhances the opportunity for gene pyramiding and expedites the process of breeding for resistance. Wild relatives of wheat have a large of resistance resources, and are a rich gene source for disease resistance. The objectives of the present studies were to identify and tag several powdery mildew resistance genes introgressed into wheat from some wild relatives of wheat using microsatellite markers, and using linked microsatellite markers to detect the powdery mildew resistance genes in many advanced lines derived from these wild relatives of wheat. The results will provide useful information for rapidly and effectively using the powdery mildew genes.The resistance genes in 11 tetraploid wheat-Aegilops amphidiploids, T. carthlicum acc. PS5, T. durum ace. DR147, 4 Aegilops accessions and advanced lines Am9/Laizhou953*2 F5 and (DR147/Ael4) //Laizhou953*2 F4 were analyzed by inoculating detached primary leaf segments with a set of 20 differential powdery mildew isolates. By comparisons of the response pattern of differential wheat cultivars or lines to the 20 isolates and pedigree analysis, we deduced that resistancegene Pm4b occurred in line Am9/Laizhou953* FS, and an unknown resistance gene in combination with resistance gene Pm4b occurred in T. carthlicum ace. PS5. Line (DR147/Ael4)//Laizhou953*2 F4 and T. durum aac. DR147 possessed an unknown resistance gene in combination with resistance gene Pm4a. Ae. caudata ace. Ael4 andAe. umbellulata ace. Y39 should carry a novel resistance gene.A dominant major gene conferring resistance to powdery mildew of wheat was identified in a BC2F2 population derived from a cross between amphidiploid Am4 and wheat cv. Bainong3217. The gene originated in T. carthlicum ace. PS5, the tetraploid wheat parent of Am4. Microsatellite marker Xgwm356 was identified to be linked to the gene with a genetic distance of 10.2cM. Based on the location of marker Xgwm356 on wheat chromosome, the gene was located on the wheat chromosome 2AL. Because both the gene and documented gene Pm4b originated from T. carthlicum, and was located on region of wheat chromosome 2AL near the gene Pm4b, it maybe either Pm4b, or a new gene linked to Pm4b. Temporarily, the gene was designated as PmPS5A.A dominant major gene conferring resistance to powdery mildew was identified in a BC3F2 population derived from a cross of amphidiploid Am9 and wheat cv. Laizhou953. The gene originated from T. carthlicum ace. PS5, the tetraploid wheat parent of Am9. Four microsatellite markers Xwmc317, Xgwmlll, Xgwm382 and Xgwm526 were found to be linked to the gene. On a genetic map of the gene and the linked microsatellite markers, the gene was flanked by markers Xwmc317 andXgwm526 at 1.1 cM and 18.1cM, respectively. Markers Xgwmlll and Xgwm382 were mapped on the same side as marker Xwmc317, and linked to the gene with genetic distance of 2.2cM and 4.0cM, respectively. Based on the chromosome location of the linked micro satellite markers in wheat, the gene was located on wheat chromosome 2BL. The gene was different from the gene Pm6 and Pm26 located on wheat chromosome 2B, it should be a novel powdery mildew resistance gene. Temporarily, the gene was designated as PmPSSB. It is proposed that the gene is designated as Pm32.A new gene conditioning resistance to wheat powdery mildew was identified in a BCsFs population derived from a cross of amphidiploid Am9 and wheat cv. "Laizhou953". Microsatellite markers Xgwm296, Xgwm257, and Xgwm319 were identified to cosegregate with the gene. Markers Xgwm257 and Xgwm319 were resistant codom更多还原