【作者】 高翔；

【导师】 周宝良；

【作者基本信息】 南京农业大学 ， 作物遗传育种， 2015， 硕士

【摘要】 棉花是重要的天然纺织原料,在国民经济中占有重要地位。棉属有4个栽培种,其中陆地棉（Gossypiun.hirstumL.）栽培种的纤维产量占世界棉花总纤维产量的90%以上。经过人类长期的人工选择与遗传改良,导致棉花遗传多样性的丧失,遗传基础日益狭窄,优异基因资源匮乏。因此,利用棉花野生或半野生材料与陆地棉杂交,向陆地棉渐渗优异基因,不断丰富棉花的遗传背景,从而扩大棉花的遗传基础,培育新的棉花优异种质资源,对现代棉花品种改良的可持续发展具有深远意义。本研究主要以陆地棉野生种系阔叶棉TX-34和陆地棉遗传标准系TM-1为亲本,开展具有共同TM-1遗传背景渐渗系的培育与评价研究,主要研究结果如下:1.利用前期研究筛选获得的陆地棉TM-1与阔叶棉TX-34的285对多态性引物,和96个单株构成的BC1群体,构建了包含有221个标记位点,涉及33个连锁群,涵盖A、D亚组共计20条染色体的遗传图谱,遗传图谱总长1501.8cM,覆盖棉花基因组总长的32.23%,标记间平均遗传距离6.8cM。其中At亚组有标记位点142个,覆盖At亚组10条染色体,总长879.2cM,标记间平均遗传距离6.2cM;Dt亚组有标记位点79个,覆盖Dt亚组10条染色体,总长622.6cM,标记间平均遗传距离7.9cM。2.构建了以阔叶棉TX-34为供体、陆地棉TM-1为遗传背景的149个染色体片段渐渗系,渐渗片段覆盖棉花全基因组总长28.82%,片段最短为0.1cM,最长为54.5cM,每个渐渗系材料中渐渗片段为4-31个不等,平均17.3个,渐渗系平均渐渗片段长度为 6.4cM。3.通过对渐渗系群体BC₃F₂世代单株和BC₃F_2:3世代株系的田间产量性状和纤维品质性状进行分析,用QTL IciMapping 4.0软件进行群体相关性状的QTL定位,选取LOD值大于2.5为标准,共定位到了 22个与铃重、衣分、籽指、衣指、纤维长度、马克隆值、纤维伸长率等7个性状相关的QTL位点。其中与铃重相关的QTL位点3个,5个与衣分性状相关的QTL位点,3个籽指相关的QTL位点,1个衣指相关的QTL位点,4个纤维长度相关的QTL位点,4个纤维伸长率相关的QTL位点以及2个马克隆值相关的QTL位点。此外还得到2个成簇的QTL位点,分别为A5号染色体上纤维长度和纤维伸长率性状相关的QTL位点,以及D10号染色体上铃重和纤维长度性状相关的QTL位点。D1号染色体上1个衣分性状相关的QTL位点在2个世代都有被检测到。4.渐渗系材料中获得与铃重、衣分、纤维长度和纤维强度等性状相关的优良种质材料12个。更多还原

【Abstract】 Cotton（Gossypium spp.）is an important commercial crop,which contains four cultivated species.Upland cotton,Gossypium hirsutum as one of the four cultivated species,dominates the world’s cotton fiberproduction accounting for approximately 90%of the total production.With long and extensive selection and improvement,current upland cotton cultivars showed high yield or resistant to diseases,however,which also lead to narrow genetic base and low genetic diversity.Primitives or landraces of cultivated species,such as G.hrisutum race latifolium native to the central America,possess invaluable characteristics unavailable in the cultivated cotton gene pool,such as high fiber quality,resistances to diseases or tolerance to drought,which are extremely useful for the improvement of tetraploid（G.hirsutum）cotton.Here,G.hirsutum race latifolium acc TX-34 was employed to introgress durable traits into a common recipient,Texas Marker-1（TM-1）,a genetic standard for future breeding.AB-QTL model was used for QTL mapping.The main results were as follows:Total of 285 markers found to be polymorphic between parents were then used to survey BC1（96）mapping populations.A total of 221 loci mapped in the genetic map which had 33 linkage groups.There were 18 groups with 142 loci in A-subgenome with full length 879.2 cM and average distance 6.2 cM.There were 15 groups with 79 loci in D-subgenome with full length 622.6 cM and average distance 7.9 cM.The total length of the map was 1501.8 cM,covering 32.23%of the cotton genome.One hundred and forty-nine chromosome segment introgression lines（CSILs）were developed.The length of the CSILs segments covered 28.82%of the whole cotton genome,ranged from 0.1 to 54.5cM and the averge length was 6.4cM.The number of the segments in CSILs ranged from 4 to 31 and the average was 17.3.QTL IciMapping 4.0 software was used to analyze on the data of yield and fiber related traits of the BC₃F₂ and BC₃F_2:3 populations.We found that 22 QTLs were associated with boll weight（BW）,lint percent（LP）,seed index（SI）,lint index（LI）,fiber length（FL）,fiber micronaire value（MV）and fiber elongation（FE）.Three QTLs for BW,5 QTLs for LP,3 QTLs for SI,1 QTL for LI,4 QTLs for FL,4 QTLs for FE and 2 QTLs for MV were mapped with the LOD>2.5 threshold.Total of 12 elite germplasms,including bigger boll size,high lint percentage,longer fiber or stronger fiber,were developed for future breeding.更多还原