An SSR- and AFLP-based genetic linkage map of tall fescue (Festuca arundinacea Schreb.)
An SSR- and AFLP-based genetic linkage map of tall fescue (Festuca arundinacea Schreb.)
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DOI：
10.1007/s00122-004-1843-1
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发表时间：
2005-01-01
影响因子：
5.4
通讯作者：
Hopkins, AA
中科院分区：
文献类型：
--
作者：
Saha, MC;Mian, R;Hopkins, AA
高羊茅(Festuca arundinacea Schreb.)在世界温带地区通常作为饲料和草皮种植。在这里，我们报道了第一个用基于聚合酶链式反应的标记构建的高羊茅遗传图谱。利用高羊茅和禾本科植物的扩增片段长度多态(AFLP)和表达序列标签-简单序列重复序列(EST-SSR)相结合的方法构建图谱。对高羊茅×黑麦草杂交种的基因组SSR进行了定位。利用双向伪测交作图策略构建了两个亲本图谱。雌性(HD28-56)图谱包括位于22个连锁群(LGs)的558个座位，覆盖基因组2,013 cM。在雄性(R43-)图谱中，579个座位被聚为22个LG，图谱总长度为1,722 cM。两个图谱的标记密度为3.61 cM(母本)~2.97 cM(父本)。这些图谱长度的差异表明父本的重组水平降低了。双亲间表现出多态且分离比为3：1的标记被用作连接两个亲本图谱的桥梁基因座，形成双亲共识。该整合图谱在17个LG上覆盖1841 cM，平均每个Lg有54个座位，平均每个标记有2.0 cM的标记密度。对预测的7个同源类群中的6个连锁群之间的同源关系进行了鉴定。HD28-56图中的三个小组和R43-图中的四个小组尚未整合。其中四组人的同源同源物被检测出来。除了几个空隙，标记在基因组中分布得很好。在整合图谱的4个LG中观察到那些表现出明显分离扭曲的标记的聚集性(占总数的23%)。
Tall fescue (Festuca arundinacea Schreb.) is commonly grown as forage and turf grass in the temperate regions of the world. Here, we report the first genetic map of tall fescue constructed with PCR-based markers. A combination of amplified fragment length polymorphisms (AFLPs) and expressed sequence tag-simple sequence repeats (EST-SSRs) of both tall fescue and those conserved in grass species was used for map construction. Genomic SSRs developed from Festuca x Lolium hybrids were also mapped. Two parental maps were initially constructed using a two-way pseudotestcross mapping strategy. The female (HD28-56) map included 558 loci placed in 22 linkage groups (LGs) and covered 2,013 cM of the genome. In the male (R43-64) map, 579 loci were grouped in 22 LGs with a total map length of 1,722 cM. The marker density in the two maps varied from 3.61 cM ( female parent) to 2.97 ( male parent) cM per marker. These differences in map length indicated a reduced level of recombination in the male parent. Markers that revealed polymorphism within both parents and showed 3: 1 segregation ratios were used as bridging loci to integrate the two parental maps as a bi-parental consensus. The integrated map covers 1,841 cM on 17 LGs, with an average of 54 loci per LG, and has an average marker density of 2.0 cM per marker. Homoeologous relationships among linkage groups of six of the seven predicted homeologous groups were identified. Three small groups from the HD28-56 map and four from the R43-64 map are yet to be integrated. Homoeologues of four of those groups were detected. Except for a few gaps, markers are well distributed throughout the genome. Clustering of those markers showing significant segregation distortion (23% of total) was observed in four of the LGs of the integrated map.