【作者】 陈晖；

【导师】 祁建民；

【作者基本信息】 福建农林大学 ， 生化与分子生物学， 2010， 硕士

【摘要】 黄麻是天然的纤维作物,在国计民生中具有十分重要的地位。然而其在构建遗传连锁图谱及利用分子标记辅助育种方面,明显滞后于其他主要经济作物。目前,国内尚未有关长果黄麻遗传连锁图谱构建的报道。本研究利用SRAP分子标记构建国内首张长果种黄麻遗传连锁图谱,为长果种黄麻某些重要农艺性状的基因定位、QTL分析及分子标记辅助育种奠定了坚实的理论基础。本研究取得了以下的研究成果:(1)以甜麻(长果野生种)和宽叶长果(长果栽培种)为亲本,杂交产生F1代,F1自交产生的F2代分离群体(187个单株),作为构图群体。(2)以甜麻和宽叶长果为模板,从19X27对SRAP上游与下游引物组合中筛选出多态性较好的56对SRAP引物组合。(3)利用筛选出的56对SRAP引物组合,对F2作图群体进行PCR扩增,共产生155个多态条带,平均每个引物组合产生2.8个多态条带,最多的可以产生6条。(4)使用Mapmaker/exp 3.0,我们构建了包括125个SRAP标记位点的长果种黄麻的遗传连锁图谱,并对长果种黄麻重要质量性状基因进行定位和标记,这些标记被分为10个连锁群(LOD≥3.0),每对标记组合可以产生8~20个大小在100~2000bp清晰可辨的条带,每个连锁群有2~38个标记位点,总长为2231.9cM,两个标记间平均图距为17.86 cM。标记间最大间距为36.6cM,最小间距为4.5cM。标记在整个连锁群中分布比较均匀,未出现标记聚集的现象。(5)质量性状定位:在本图谱中有3个形态标记,分别为托叶色、叶柄色和叶缘色。三者均位于构建的连锁群LG1上,托叶色基因与M18E7及M12E18连锁,遗传距离分别为11.2cM和12cM;叶柄色基因与M17E10及叶缘色基因连锁,遗传距离分别为21.1cM和4.5cM;叶缘色基因还与M12E9-1连锁,遗传距离为20.9cM。(6)在这155个标记位点当中,有37个(23.9%)偏离3:1的分离比,偏分离比较严重。其中有28个(75.7%)偏向父本(甜麻)带型,其余9个(24.3%)偏向母本(宽叶长果)带型,可能是由配子的选择性引起的。长果种黄麻有7对染色体,而我们构建出10个连锁群,接近染色体数。本研究的平均图距还较大,有待于进一步深化,以期构建出一张标记分布均匀,位点密度较高的长果种黄麻遗传连锁图谱。更多还原

【Abstract】 Jute(Corohorus olitorius L)is a nature fiber crop and plays a very important position in people′s livelihood. However, in the construction of genetic linkage map and the use of molecular marker-assisted breeding, it drops behind the other major crops. By now, there is no relative report on genetic linkage map of jute. In this study, SRAP markers were applied to construct the first jute genetic linkage map in country, which laid a solid foundation for the theory of agricultural traits of gene mapping, QTL analysis, molecular marker-assisted breeding. The major results as below:(1) The 187 F2 individuals are from the cross of two jute, glyc-anesthesia (wild species) and wide leaf jute (cultivated species).(2) Take glyc-anesthesia (wild species) and wide leaf jute (cultivated species) as template, 56 pairs of SRAP primer combinations with good polymorphism were selected from 19X27 forward and reverse of the SRAP primer combinations.(3) Using the screened 56 pairs of SRAP primer combinations, PCR was applied on the F2 population. 155 polymorphic bands were generated in the F2 population analysis. The average of polymorphic bands produced by one primer pair was 2.8, and the maximum was 6.(4) Using mapmaker/exp 3.0, a linkage map was constructed, which consisted of 125 SRAP markers distributed in ten linkage groups (L0D≥3 0). Each SRAP primer pair could generate 8~20 clear bands with a length range between 100 and 2000 bp.While each linkage group have 2~38 markers, 2231.9cM in total. The average map distance is 17.86cM, with the maximum map distance is 36.6cM and the minimum map distance is 4.5cM. The markers are well-distributed with aggregation in each linkage group.(5) Position of qualitative traint:There were 3 morphological markers in the map.They were the colour of stipule,the colour of stipe and the colour of leaf margin. They were located in the linkage group 1.The colour of stipule linkaged with M18E7 and M12E18. The genetic distance between them are 11.2cM and 12 cM. The colour of stipe linkaged with M17E10 and the colour of leaf margin.The genetic distance are 21.1cM and 4.5cM.The colour of leaf margin linkaged with M12E9-1 and the genetic distance is 20.9cM.(6) Among these 155 markers,37 markers (23.9%) segregated unconventionally against the expected 3:1 ratio.28 (75.7%) with the type of male parent, and the other 9 (24.3%) preferred the type of female parent, which could be caused by selectivity of gametes. Although jute has 7 pairs of chromosomes,we constructed ten linkage groups, which close to the chromosome number. In this study,the average map distance is too large, which requires to be further deepened for building a genetic linkage map of Jute with evenly-distributed markers and high-density sites.更多还原