Nissan-Azzouz Farida, Graner Andreas, Friedt Wolfgang, Ordon Frank
Institute of Crop Science and Plant Breeding I, Justus-Liebig-University, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany.
Theor Appl Genet. 2005 Jan;110(2):212-8. doi: 10.1007/s00122-004-1802-x. Epub 2004 Dec 1.
Barley yellow mosaic disease caused by the bymoviruses barley mild mosaic virus (BaMMV) and barley yellow mosaic virus (BaYMV) is one of the economically most important diseases of winter barley in Europe. In European barley breeding programmes, resistance is currently due to only two genes-rym4, which is effective against viruses BaMMV and BaYMV-1, and rym5, which is effective against BaYMV-2. Diversification of resistance is therefore an important task. Because the accession PI1963 confers immunity against all European strains of barley yellow mosaic disease and is not allelic to rym5, we have attempted to develop closely linked markers in order to facilitate the efficient introgression of this resistance into adapted germplasm. By means of restriction fragment length polymorphism analysis, we located a gene locus for resistance to BaMMV, BaYMV-1 and BaYMV-2 of PI1963 on chromosome 4HL using a mapping population (W757) comprising 57 doubled haploid (DH) lines. Subsequent tests for allelism indicated that the BaMMV resistance gene in PI1963 is allelic to rym11. Two DH populations, IPK1 and IPK2, comprising 191 and 161 DH lines, respectively, were derived from the initial mapping population W757 and used for further analysis. As random amplified polymorphic DNA development did not facilitate the identification of more closely linked markers, simple sequence repeat (SSR) analyses were conducted. For population IPK1, the closest SSRs detected were Bmac181 and Bmag353, which flank the gene at 2.1 cM and 2.7 cM, respectively. For the IPK2 population, the SSR markers HVM3 and Bmag353 are located proximally at 2.5 cM and distally at 8.2 cM, respectively. In order to develop markers more tightly linked to rym11, a targeted amplified fragment length polymorphism (AFLP) marker identification approach was adopted using bulks comprising lines carrying recombination events proximal and distal to the target interval. Using this approach we identified six AFLP markers closely linked to rym11, with the two markers, E56M32 and E49M33, co-segregating with rym11 in both populations. The SSRs and AFLPs identified in this study represent useful tools for marker-assisted selection.
由大麦温和花叶病毒(BaMMV)和大麦黄花叶病毒(BaYMV)这两种大麦黄花叶病毒引起的大麦黄花叶病是欧洲冬大麦最重要的经济病害之一。在欧洲大麦育种计划中,目前的抗性仅归因于两个基因——rym4,对病毒BaMMV和BaYMV - 1有效;以及rym5,对BaYMV - 2有效。因此,抗性多样化是一项重要任务。由于种质PI1963对所有欧洲大麦黄花叶病株系都具有免疫性,且与rym5非等位,我们试图开发紧密连锁的标记,以便将这种抗性高效导入适应性种质中。通过限制性片段长度多态性分析,我们利用一个由57个加倍单倍体(DH)系组成的作图群体(W757),在4HL染色体上定位了PI1963对BaMMV、BaYMV - 1和BaYMV - 2的抗性基因座。随后的等位性测试表明,PI1963中的BaMMV抗性基因与rym11等位。分别由191个和161个DH系组成的两个DH群体IPK1和IPK2,从初始作图群体W757衍生而来,并用于进一步分析。由于随机扩增多态性DNA开发未能促进更紧密连锁标记的鉴定,因此进行了简单序列重复(SSR)分析。对于群体IPK1,检测到的最紧密的SSR是Bmac181和Bmag353,分别在基因两侧2.1 cM和2.7 cM处。对于IPK2群体,SSR标记HVM3和Bmag353分别位于近端2.5 cM和远端8.2 cM处。为了开发与rym11更紧密连锁的标记,采用了一种靶向扩增片段长度多态性(AFLP)标记鉴定方法,使用包含在目标区间近端和远端携带重组事件的株系的混合群体。利用这种方法,我们鉴定了六个与rym11紧密连锁的AFLP标记,其中两个标记E56M32和E49M33在两个群体中都与rym11共分离。本研究中鉴定的SSR和AFLP代表了标记辅助选择的有用工具。