【作者】 唐媛；

【导师】 傅体华；

【作者基本信息】 四川农业大学 ， 植物资源保护与利用， 2008， 硕士

【摘要】 小麦是世界上第二大粮食作物,在我国是仅次于水稻和玉米的第三大粮食作物。随着世界人口的不断增加以及人们生活水平的提高,对小麦产量和品质的要求越来越迫切。因此,保持小麦生产持续稳定的发展,对维护粮食安全意义重大。小麦病害的发生,严重影响了小麦的产量和品质。小麦白粉病和小麦条锈病是小麦生产上两个最为主要的病害。小麦白粉病和条锈病是由专性寄生菌所引起的世界性小麦病害,该病害在我国发生较为普遍,目前随着氮肥和单一抗性基因材料的运用有加重趋势,利用抗病新品种控制白粉病是最经济、安全和有效的途径。迄今为止,小麦白粉病抗性基因至少已在34个位点上发现了50个以上抗白粉病主效基因,并将一些有效抗病基因转育到生产品种中。已有50多个抗小麦条锈病基因被发现,其中在38个基因位点的41个主效基因被正式命名,除Yr11-Yr14以外的已知基因均被定位于特定的染色体或染色体臂上,并有许多基因已获得其DNA分子标记。101-3是从簇毛麦与小麦栽培品种绵阳11杂交后代中选育出的一个小麦新品系,含有一个显性抗白粉病基因和一个显性抗条锈病基因。两个基因已用单体分析的方法定位于6B和1B染色体上。本研究以感白粉病和条锈病小麦品种中国春与101-3及其杂交后代F₂为材料,利用ISSR和SSR标记对小麦品系101-3中的抗白粉病基因和抗条锈病基因进行分子标记。实验选取了100ISSR个引物,其中有37个在中国春中扩增出稳定的多态性,其中17个引物在中国春和101—3之间有多态性,但是分别在白粉病和条锈病抗病池和感病池没有差异。原因可能是小麦基因组庞大,而目前的ISSR引物有限,扩增不到目的片段,或者是ISSR不适合于BSA群体或样本。用65对6B染色体上和9对6A染色体上小麦微卫星引物,对白粉病进行连锁分析,发现小麦微卫星标记Xgwm570与基因的遗传距离为9.72cM,尽管Xgwm570在6A上也有扩增位点,但结合单体分析结果表明该基因位于小麦染色体6BL上。104对1B染色体上染色体上小麦微卫星引物,对条锈病进行连锁分析,发现小麦微卫星标记WMC419和WMC216与基因的遗传距离分别为8.2cM和5.8cM,该结果表明该基因位于小麦染色体1BL上,该基因与位于1B上的已知条锈病基因来源及其标记都存在差异,表明可能是一个新的抗条锈病基因,这为以后分子标记辅助育种上利用这两个基因提供了初步的选择标记。更多还原

【Abstract】 Wheat powdery mildew and yellow rust caused by Erysiphe graminis f.sp.tritici . and caused by puccinia striiformis Westend, f.sp.tritici. respectively, are two important foliar disease of wheat and important fungal diseases of wheat in many regions in the world . A novel dominant powdery mildew resistance gene and a dominant stripe rust resistance gene, temporarily named PmX and Yr101-3,respectively, in a new wheat line 101-3 derived from the progeny of the cross between common wheat and Dsypyrum villosum Candery L. was located on chromosome 6B and 1B by monosomic analyses.In the present study, SSR promers mapped in the chromosome 6B and 6A of common wheat were used for PCR amplification using the genomic DNA of resistant and susceptible bulks between 101-3 and Chinese Spring and their parents to tag the powdery mildew resistance gene in line 101-3. No polymorphic products were observed in most primers. However, one primer Xgwm570 , amplified polymorphic among resistant and susceptible bulks and their parents. The primer Xgwm570 was then used to amplify DNA of the F₂ population from the cross 101-3/Chinese Spring. The result indicate that primer Xgwm 570 was linked to the resistance gene PmX with the genetic distance 9.72cM suggested that the PmX might be located in the chromosome 6BL of common. There are amplified sites in 6AL and 6BL and using Xgwm570 as primer the result of monosomic analysis indicatied that the resistance gene of prowery mildew was located on 6B.104 SSR markers distributed on the chromosome 1B were chosen for screening for polymorphisms between the parents and two bulks, Two markers WMC419 and WMC216 were polymorphic between the two bulks and two parents. Primer pair WMC419 revealed 2 polymorphic fragments between the two bulks and two parents, with sizes of 145bp and 115bp in Chinese Spring and 165bp and 145bp in 101-3. WMC216 amplified fragment with size of 135bp in Chinese Spring and 125bp in 101-3.These two microsatellite markers showed 1:2:1 segregation in the 128 F₂ population from the between Chinese Spring and 101-3, These results indicated that the two microsatellites are co-dominant markers genetic distances of 8.2cM and 5.8cM. Based on the origin and molecular markers of stripe rust gene in line 101-3 might be a new gene for stripe rust resistance.更多还原