【作者】 裴静宇；

【导师】 杨信东； 牛永春；

【作者基本信息】 吉林农业大学 ， 植物病理学， 2006， 硕士

【摘要】 小麦条锈病是由小麦条锈菌引起的小麦叶部病害，该病害发生面积广，流行频率高，危害严重。我国小麦条锈病流行体系是一个相对独立的体系。目前，防治小麦条锈病主要是使用抗病品种和化学防治，但不论是利用抗病品种还是化学防治，都必须快速及时了解小麦条锈菌生理小种的动态或毒性变异趋势。关于体细胞重组(异核作用)前人有了一些初步研究，但到底是否可通过体细胞重组导致毒性变异没有确切的理论依据。本研究利用10个菌系以及白化菌进行了体细胞重组产生新菌系的筛选。并利用24对SSR引物对异核菌系和我国小麦条锈菌主要流行小种进行了DNA多态性分析。 1．在进行异核菌系筛选过程中，有四个组合筛选出了异核菌系。即1号菌系、2号菌系、3号菌系、4号菌系。新菌系的毒性特征明显不同于对应原始菌系。在利用SSR引物RJ24对稳定的4号异核菌系进行分析后，获悉新菌系是通过核的重新组合分配后体细胞杂交(即菌系融合、异核作用)的结果。从分子水平上进一步证实了该新菌系是由两个原始菌系经过异核作用产生的。 2．利用RJ3引物对所选取的15个小麦条锈菌生理小种和三个国外菌系进行了DNA多态性的分析，可以得到白化菌系不同于其它供试小种的170bp左右的特异性扩增片段，经过参试菌系的重复验证，该特异性片段能稳定清晰再现。为后期研究颜色变异或无毒基因提供了参考。 3．利用SSR引物RJ18对17个小麦条锈菌生理小种21个菌系进行DNA多态性分析，在CY26小种上获得了300bp左右特异性扩增片段。进一步对该片段进行了验证，发现该片段仍仅存在于CY26小种上，初步结果表明RJ18引物可以用于CY26的检测。 4．利用SSR引物RJ4引物对17个小种23个菌系进行DNA多态性分析，获得了CY29小种的210bp左右的特异性谱带，经过参试菌系的重复验证发现，该片段能够在CY29上稳定存在，初步表明RJ4引物可以用于CY29的检测。 5．利用引物RJ20对11个小麦条锈菌生理小种进行筛选时获得长度约为310bp的可能与Yr9毒性谱相关的特异带。经过参试菌系的重复验证发现，该片段能够稳定存在，对研究毒性变异提供了一些参考。 本研究获得的有关小麦条锈菌群体毒性变异和小种的信息，可以为未来研究小麦条锈菌的毒性变异和群体进化及监测提供一些参考和帮助。更多还原

【Abstract】 Wheat stripe rust (Puccinia striiformis West. f.sp. tritici) is common and serious in China. The Chinese region is the biggest and unique epidemic region of wheat stripe rust in the world. Presently,the better methods against the wheat stripe rust are using resistance cultivars and chemicals. But whatever measures will be taken, the first step is to observe the virability of virulence and the structure of the populations of Puccinia striiformis West. f.sp. tritici in shortest time.The reason how new virulent isolates product is virlence variance. The fungi can variant through gene mutation and heterokaryosis, heterokaryosis had have some pilot study. But the reports about variation on level of molecule in Puccinia striiformis were not found.The study is to select new islate of wheat rust from the mixture of two original races with ten isolates and white isolate.And to find DNA polymorphisms in 17 races with SSR (microsatellite markers). The results as follows:1.Four new isolates has been obtained from the mixture of different races, reproducing on the same wheat cultivar simultaneously It found that the virulence of the new isolates was obviously different from that of original races .the SSR primer RJ17 was used to analyze the new isolate and other experimental isolates. We learned the new isolate that was producted by heterokaryosis.2. One about 170bp special polymorphism band of white race has been obtained when the SSR primer RJ3 was used to analyze the 17 experimental isolates.3. One about 300bp special polymorphism band of CY26 has been obtained, when the SSR primer RJ18 was used to analyze the 17 experimental isolates.4. One about 210bp special polymorphism band of CY29 has been obtained when the SSR primer RJ4 was used to analyze the 17 experimental isolates. Then the band was affirmed by repeat experiment.5. About 310bp special polymorphism band related virulence gene to Yr9 has been obtained, when the SSR primer RJ24 was used to analyze the 17 experimental isolates.The study obtained message about virulence viariation and races of Puccinia striiformis West. f.sp. tritici can offer consult and help for wheat rust study about variation and evolution.更多还原