【作者】 张玉；

【导师】 王保通；

【作者基本信息】 西北农林科技大学 ， 植保资源利用， 2013， 硕士

【摘要】 小麦条锈病是由小麦条锈菌（Puccinia striiformis f. sp. tritici）引起的真菌病害，可随高空气流进行远距离的传播，给小麦生产造成巨大损失。我国是世界上最大且相对独立的小麦条锈病流行区，主要分布在西北、西南、黄淮海等冬麦区和西北春麦区。在条锈病流行年份可导致小麦减产20~30%，特大流行年份减产50%以上甚至绝收。1999~2009年，我国平均每年受灾的小麦面积约为400万hm2。国内外研究以及生产实践表明，培育和推广抗病品种是防治小麦条锈病最经济、有效和环保的措施。然而由于目前大面积推广抗病品种的抗源单一以及条锈菌毒性变异频繁，致使种植小麦的抗锈性屡屡“丧失”。20世纪50年代至今，我国小麦条锈病主要流行区已经因品种抗病性“丧失”进行了7次大规模的品种更替。小麦抗条锈病基因的挖掘是培育和合理利用抗病品种的基础。因此寻找新的抗源、发掘和利用小麦抗条锈病新基因、丰富抗病基因的遗传背景成为小麦育种工作者的首要任务。柔软滨麦草（Elymus mollis (Trin.) Hara JJNN2n=28）具有抗干旱、耐盐碱、茎秆粗壮、大穗多花、对小麦条锈病等多种病害有良好抗性等优良性状，是挖掘小麦抗病基因的珍贵抗源。利用柔软滨麦草与普通小麦杂交、回交，已经培育了一批农艺性状优良的柔软滨麦草异源种质系。甘肃地区是小麦条锈病的重发区，也是我国小麦条锈病的重要菌源地。兰天18、天选45和天选46均是该地区的小麦品种，田间种植效果证实其对小麦的多种病害均具有良好地抗病性，说明其中可能蕴藏着丰富的抗条锈病基因。本研究对15个普通小麦-柔软滨麦草易位系和3个甘肃小麦品种的抗条锈性进行了研究，得到以下结果：1、采用7个我国条锈菌生理小种CYR29、CYR31、CYR32、CYR33、Su11-4、Su11-7和Su11-11对15个普通小麦-柔软滨麦草易位系进行苗期抗条锈性评价（以易位系表现的最高反应型为准），结果表明：5个易位系M852-1、M8657-2、M8724-1、M8725-2和M8926-2表现为免疫至高抗（0~1~+）；6个易位系M8003-14-4、M8003-6、M8003-5、M851-2、M857-1和M8664-5表现为中抗（2~2~+）；4个易位系M8926、M8664-3、M8007-1和M851-1表现为感病（3-~4）。2、对6个普通小麦-柔软滨麦草易位系与感病品种铭贤169杂交后代群体，分别接种我国优势小麦条锈菌生理小种CYR32和CYR33，苗期抗条锈性遗传分析结果表明：M852-1对CYR33的抗条锈性由1对隐性基因控制；M851-1对CYR32的抗条锈性由1对隐性基因控制；M8724-1对CYR32的抗锈性由2对隐性基因独立作用控制，对CYR33的抗锈性由1对隐性基因独立控制；M8725-2对CYR32的抗锈性由2对显性基因互补作用控制，对CYR33的抗锈性由1显1隐两对基因独立控制；M8657-2对CYR32的抗锈性由1对隐性基因控制，对CYR33的抗锈性由2对显性基因独立控制；M8926-2对CYR32的抗锈性由1对显性基因控制，对CYR33的抗锈性由1显1隐两对基因互补作用控制。3、M852-1对7个我国条锈菌生理小种CYR29、CYR31、CYR32、CYR33、Su11-4、Su11-7和V26均表现免疫或近免疫。用我国条锈菌优势小种CYR33对M852-1与铭贤169杂交F1、F2、F3和BC1代进行遗传分析，发现M852-1对CYR33的抗条锈性由1对隐性基因控制，暂命名为YrElm。以M852-1与铭贤169杂交的F2代分离群体构建作图群体，利用集群分离分析法（BSA法），筛选到与YrElm连锁的5个SSR标记：Xcfd35、Xgwm161、Xwmc630、Xgwm533和Xcfd34，将YrElm定位于小麦染色体3DS上。YrElm两侧最近两个SSR标记Xcfd35与Xgwm161的与其遗传距离分别为6.5cM和4.2cM。系谱分析、抗锈性鉴定以及分子标记检测结果表明，该抗病基因来源于柔软滨麦草。综合基因来源、分子检测及染色体位点等方面的分析，YrElm可能是一个新的抗条锈病基因。用基因两侧最近两个标记Xcfd35和Xgwm161检测68个甘肃和黄淮麦区小麦品种（系），仅14.7%的品种能扩增到与M852-1相同的条带。系谱分析的结果显示，其中均不含有抗病基因YrElm，说明其在抗病育种中的应用潜力巨大。本研究结果为利用YrElm进行分子标记辅助育种和进一步的精细定位奠定了基础。4、三个甘肃小麦品种的苗期抗条锈性鉴定结果表明，兰天18对供试菌种CYR31、CYR32、CYR33、Su11-4、Su11-7和Su11-11均表现高抗，天选45和天选46除对CYR32表现感病外，对其他小种均表现抗病。遗传分析结果表明：兰天18对CYR32的抗条锈性由2对显性基因互补控制，对CYR33的抗条锈性由1对显性基因独立控制；天选45对CYR33的抗锈性由1对隐性基因独立控制；天选46对CYR33的抗锈性由1对隐性基因独立控制。这为进一步利用这些抗病基因进行分子标记和抗病育种以及抗病品种的合理布局奠定了基础。更多还原

【Abstract】 Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the mostimportant diseases of wheat worldwide, especially in China, which is the largest andrelatively independent disease epidemic area. In China, wheat stripe rust mainly occurs innorthwestern, southwestern and huanghuai wheat regions. Epidemic of this disease couldcause about twenty to thirty percent loss on wheat production, even reached to fifty percentif epidemic severe. During1999to2009,4million hectares of wheat suffered from stripe rustevery year averagely in China. It is known that growing resistant cultivars is the mosteconomical, effective and environmental approach to control this disease, according tooverseas and domestic researches and production practice. Due to the simplification ofdisease-resistant wheat cultivars and frequent variation of pathogenic bacteria, less and lesswheat cultivars could resist this disease. Since the1950s, Chinese wheat cultivars have beenreplaced for seven times in main disease epidemic regions. The breeding and utilization ofresistant wheat cultivars bases on excavation of wheat stripe rust resistance gene. So, it isurgent to search for new stripe rust resistance gene for pyramiding genes to achieve high-leveland durable disease-resistance for sustainable control of stripe rust.Elymus mollis is a precious resource for excavating wheat stripe rust resistance genes,with many advantageous traits, such as drought-resistance, salt-tolerance, large panicle, multiinflorescence and resistance to various wheat diseases. Gansu region is not only the birthplaceof Chinese wheat stripe rust fungus, but also severe epidemic area of wheat stripe rust.Lantian18, Tianxuan45and Tianxuan46have been widely grown in Gansu region for manyyears, and resistant to many diseases of wheat. The objective of this study were to identify thegenes for stripe rust resistance in these wheat cultivars (lines) using genetic and molecularmakers. The results are as follows:1、Using seven Pst races of China including CYR29、CYR31、CYR32、CYR33、Su11-4、Su11-7and Su11-11to valuate the fifteen wheat-Elymus mollis translocation lines at theseeding. Five translocation lines presented0to1~+, including M852-1、M8657-2、M8724-1、M8725-2and M8926-2. Six translocation lines presented2to2~+, including M8003-14-4、 M8003-6、M8003-5、M851-2、M857-1and M8664-5. Four translocation lines presented3-~4,including M8926、M8664-3、M8007-1and M851-1.2、The crosses between six translocation lines and Mingxian169were separately testedwith Pst races CYR32and CYR33to identify the genetic of stripe rust resistance genes. Theresistance of M852-1to CYR33was controlled by a single recessive gene. The resistance ofM851-1to CYR32was controlled by a single recessive gene. For M8724-1, two independentrecessive genes conferred resistance to CYR32and one independent recessive gene conferredresistance to CYR33. The resistance of M8725-2to CYR32was controlled by twocomplementary dominant genes and resistance to CYR33was controlled by one dominantgene and one recessive gene independently. The resistance of M8657-2to CYR32wascontrolled by one recessive gene and resistance to CYR33was controlled two independentdominate genes. The resistance of M8926-2to CYR32was controlled by one recessive geneand resistance to CYR33was controlled by one dominant gene and one recessive genecomplementary.3、The M852-1was highly resistant to seven Pst races of China(CYR29、CYR31、CYR32、CYR33、Su11-4、Su11-7and V26), including the most widely virulent andpredominant pathotypes CYR32and CYR33. F1, F2, F3and BC1generations derived fromcross M852-1/Mingxian169were tested with Pst race CYR33. The genetic analysis resultsindicated that the resistance of M852-1to CYR33was controlled by a single recessive gene,tentatively designated as YrElm. The resistance gene was mapped using an F2population fromM852-1/Mingxian169and bulked segregant analysis (BSA). YrElm was linked with fivesimple sequence repeat (SSR) markers, Xcfd35, Xgwm161, Xwmc630, Xgwm533and Xcfd34,which located on wheat chromosome3DS. The genetic distances of closest flanking markers,closest flanking markers, Xcfd35and Xgwm161, were6.5cM and4.2cM, respectively.Pedigree analysisi, chromosomal location and molecular test suggested that YrElm may be anovel resisitance gene to wheat stripe rust, derived from Elymus mollis. Two closest flankingSSR markers, Xcfd35and Xgwm161, were used to test68wheat cultivars from Gansu andHuanghuai wheat region. The results showed that14.7%cultivars had the same polymorphicbands as M852-1. However, resistance identification and pedigree analysis suggested thatthese ten cultivars might not carry the stripe rust resistance gene YrElm. The polymorphicSSR markers identified in this research can be useful in wheat molecular marker selectbreeding and fine mapping.4、Lantian18was resistant to all tested Pst races(CYR31、CYR32、CYR33、Su11-4、Su11-7and Su11-11). Tianxuan45and Tianxuan46were just only susceptible to CYR32.The resistance of Lantian18to CYR32was controlled by two complementary dominate genes and resistance to CYR33was controlled by one dominant gene. The resistance ofTianxuan45to CYR33was controlled by one recessive gene, so was Tianxuan46. This workwill be useful to the proper distribution of disease-resistant wheat cultivars and the mappingof these disease resistance genes.更多还原