导　　师： 王坤波

学科专业： 090101

授予学位： 硕士

作　　者： ;

机构地区： 中国农业科学院

摘　　要： 棉花不仅是世界上主要的天然纤维,而且还是重要的油料作物之一。近几年,随着纺织技术的不断提高,对棉花的纤维品质尤其是纤维强度和细度的要求也越来越高。但是棉花的产量性状与纤维品质的负相关行,极大地阻碍了棉花品质和产量的同步提高。分子标记辅助育种能够利用精确定位的QTL,打破品质和产量之间的负相关,同步提高纤维的品质和产量。但是它需要高密度的遗传连锁图谱来精确定位目标性状的QTL。所以,本实验以陆地棉/(Gossypium hirsutum L./)优质品系爱字棉1517/(Acala 1517/)和德州047/(Dezhou 047/)为父母本,构建陆地棉种内重组近交系/(Recombined Inbred Line, RIL/)-中G6,进行三年份的重复实验。利用本实验室现有的SSR引物,对群体进行多态性筛选,并以中-G6为作图群体,构建陆地棉种内遗传连锁图谱。利用基于混合线性模型的复合区间作图法检测不同年份稳定存在的主效QTLs和上位性QTLs。为优质高产材料的选育打下坚实的基础。 陆地棉种内重组近交系中G6不同年份的多数农艺性状均符合标准的正态概率分布。中G6的相关分析显示:生育期的全生育期和霜前花率分别与生育期的其它性状呈极显著负相关,生育期与霜前花率、果枝始节与蕾期分别呈显著正相关;单株籽棉与单株皮棉呈显著正相关,单株皮棉和单株籽棉分别与单铃重和单株铃数呈显著正相关,单铃重与单株铃数和子指呈显著负相关;马克隆值与纤维品质性状/(除纤维伸长率/)呈显著负相关,纤维长度与整齐度和纤维强度呈显著正相关。衣分和单株铃数分别与全生育期和霜前花率呈显著负相关;纤维整齐度与生育期性状/(除花铃期/)呈显著相关;衣分与纤维品质性状/(除马克隆值和整齐度/)呈负相关,子指与品质性状/(除马克隆值/)呈正相关。 本实验利用11358对不同来源的SSR引物在两亲本间筛选到209对多态性引物,多态率为1.84/%。利用JionMap3.0软件/(LOD值3.0/)构建了一张包含90对标记和22个连锁群的分子遗传连锁图。连锁群总长663.08 cM,覆盖棉花基因组的13.1/%,标记间的平均距离是7.37 cM,标记间的最小遗传距离是0.098 cM。其中有16条连锁群对应到相应的染色体上,6条连锁群没有定位到任何染色体上。 采用QTLNetwork2.0软件/(P=0.005/)的基于混合线性模型的复合区间作图法/(Mixed Linear Model Composite Interval Mapping,MCIM/),对陆地棉重组近交系的主要农艺性状进行不同年份的检测,共检测到52个与主要农艺性状相关的主效QTLs,53对与主要农艺性状相关的加-加上位性QTLs。其中果枝始节、霜前花率、纤维伸长率、单株籽棉、单株皮棉、衣分、单铃重以及子指分别在不同年份检测到稳定的主效QTLs,其中稳定存在的子指的主效QTLs的遗传贡献率超过22/%。还检测到2对衣分的不同两年份稳定存在的加-加上位性QTLs和1对纤维强度的不同年份稳定存在的加-加上位性QTLs。 Cotton /(Gossypium/) is the world’s most important natural textile fiber and a significant oil crop.In recent years, improvement in the quality of cotton fiber has been extremely important because of changes in spinning technology. Negative correlation between yield and quality make it difficult to improve, simultaneously. So it is important to select high priorities of yield and quality properties from markers, which have close linkage with QTLs. So two elite Gossyium hirsutum L. line, which were Acala1517 and Dezhou047, were used as parents to construct a RIL /(Recombined Inbred Line/) population of cotton /(CRI-6/). CRI-6 was used to construct linkage group using 11358 pairs of SSR primers. Quantitative trait loci /(QTL/) analyses were performed by means of Mixed Linear Modle Composite Interval Mapping. QTL analysis may provide a useful tool for breeders. The majority of agronomic traits for CRI-6 showed normal distribution in the different years. Correlation coefficients between phenotypic traits were caculated in each of CRI-6 lines. Growth and development stages /(GDS/) and percentage of pre-frost seed cotton /(PPSC/) were negative correlation with another growth trait, respectively. GDS and PPSC, first fruiting branch node /(FFBN/) and buding steage /(BS/) were positive correlation. Seed yield /(SY/) and lint yield/(LY/) also showed positive correlation. SY and LY were positive correlation with boll size /(BZ/) and bolls number /(BN/), respectively. SY showed positive correlation with LY. Lint percentage /(LP/) and BN were negative correlation with GDS and PPSC, respectively. Uniformity index /(UI/) showed significant correlation with growth traits /(except boll-forming stage, BFS/). LP were positive correlation with fiber traits /(except micronaire /(MV/) and UI/), and seed index /(SI/) was reverse. Two hundred and nine of a total of 11358 SSR primer pairs /(1.84/%/) revealed polymorphisms between the parents. Of these, 90 SSR primer pairs were assigned to 22 linkage groups with a total map distance of 663.08 cM, which covered 13.1/% of the total recombinational length of the cotton genome. QTLs were analyzed by Mixed Linear Model Composite Interval Mapping, using Windows QTLNetwork 2.0. A total of 52 major QTLs and 53 pairs of additive epistatic QTLs for important agronomic traits were detected in the three different years. The stable major QTLs of FFBN, PPSC, seed yield /(SY/), lint yield /(LY/), lint persentsge /(LP/), seed index /(SI/) were mapped in different years, respectively. And phenotypic variance major QTL of SI was over 22/%. Two pairs of stable additive epistatic QTLs of LP were detected in different years, and one pair of stable additive epistatic QTL of FS was detected in different years.

关 键 词： 陆地棉种内重组近交系 遗传图谱 主效 上位性

分 类 号： [S562]

领　　域： [农业科学]