Genetic Diversity and Association Analysis of Fiber Quality Traits with SSR Markers in Germplasm Resources of Early Maturity Upland Cotton in Xinjiang

[Objective] We explored the genetic diversity of early maturity upland cotton germplasm resources in Xinjiang, China. We discovered specific germplasm resources and elite allelic variation related to fiber quality. [Method] We used 219 early maturity upland cotton accessions in our experiments and investigated 15 agronomic traits in three environments. We used a total of 128 pairs of simple sequence repeat (SSR) primers to scan for polymorphism. We then used NTsys-pc2.1 software to analyze genetic diversity, and Structure2.3.1 and Tassle5.0 software to perform association analysis of fiber quality traits based on phenotypic effect values to identify elite allele variation and conventional materials. [Result] A total of 244 loci were amplified by 128 marker pairs in 219 samples with an average of 1.91 loci per marker. The polymorphic information content ranged from 0.13 to 0.86 with an average of 0.63. The distribution range of the genetic similarity coefficient between materials in this population was 0.42-0.99 with an average of 0.61. The genetic similarity coefficient was between 0.5 and 0.7 and accounted for 90.19%. Through association analysis, we detected 11 markers that were significantly (P<0.01) associated with fiber quality traits, and discovered seven typical materials with specific allele. [Conclusion] In total, 219 Xinjiang early-maturing upland cotton germplasm resources have low genetic diversity. Based on SSR association analysis, we discovered some specific allele variations and conventional materials related to fiber quality traits.     

Association Analysis of Agronomic and Yield-Related Traits in an Upland Cotton (Gossypium hirsutum L.) Germplasm Population Based on SSR Markers

[Objective] Molecular markers associated with agronomic and yield-related traits could provide useful references for improving the efficiency of Gossypium hirsutum breeding. [Method] In 147 upland cotton materials, 237 Simple Sequence Repeat(SSR) markers were assayed for polymorphisms. The population structure was analyzed using Structure 2.2. An association analysis between SSR markers and the agronomic and yield-related traits was performed using the Tassel 2.1 General Linear Model program. [Result] The average coefficients of variation for the five indicators varied from 7.28% to 21.06%, with an average of 13.47%, which indicated that the test population had a rich phenotypic diversity. The 237 SSR markers included 690 alleles belonging to 281 loci, with an average of 2.455 0 alleles per SSR marker (ranging from 2 to 6), and the average polymorphism information content value was 0.216 5. The test group could be divided into seven subgroups using Structure software. A genome-wide association analysis was conducted on five agronomic and yield-related traits from 2013 to 2015. There were 45 SSR loci and 1 locus significantly (P＜0.01) associated with boll weight and lint percentage, which were detected in 3 or more environments, and they explained 19.30% and 11.58%, respectively, of the phenotypic variation in the different environments (P＜0.01). Nine loci were significantly (P＜0.01) associated with agronomic traits at two or more bowing times, and one, four and four markers were associated with fruit branch number, boll number and plant height, explaining 9.96%, 7.00% and 5.57%, respectively, of the phenotypic variation in different environments. Sites significantly associated with boll weight, fruit branch number and plant height were simultaneously detected near BNL2448. [Conclusion] Many loci associated with the yield and other important agronomic traits of upland cotton were repeatedly detected in different environments using an association analysis. The results provide useful reference information for cotton molecular marker-assisted selection-based breeding.     

三个栽培种中天然彩色棉的遗传多样性及关联分析

本研究利用主要农艺性状和SSR标记分析了137份陆地棉、13份海岛棉以及27份亚洲棉等不同纤维色泽的种质资源。170对SSR引物共检测到1036个等位基因变异。其中有多态性的等位基因923个,平均每个SSR位点有5.43个等位变异,变化范围为1~10。位点多态性信息量(PIC)的变化范围为0.56~0.93,PIC在0.85以上的多态性SSR位点为122个。结果表明,实验材料存在着丰富的遗传多样性。在群体结构分析基础上,使用TASSEL软件中的混合线性模型(MLM),在陆地棉中得到与11个性状相关联的SSR标记23个;在海岛棉群体得到与5个性状关联的17个标记;在亚洲棉中检测到与8个性状关联的15个标记位点。在三个栽培种中与纤维色泽度相关的标记位点一共有6个,分别是CIR51-4、BNL1421-2、BNL2656-2、DPL570-2、GH268-6和TMB131-1,表型变异解释率从3.12%到18.97%。三个栽培种中天然彩色棉种质具有丰富的遗传多样性,为棉花的种间、种内杂交育种以及拓宽棉花新品种的遗传背景提供了物质基础和理论依据。     

南疆陆地棉种质资源表型性状遗传多样性分析

通过田间调查、室内考种及纤维品质检测,对南疆90份陆地棉种质资源16个表型性状进行鉴定及评价分析,为南疆陆地棉亲本选配和新品种选育提供参考。结果表明:16个表型性状中叶枝数(36.24%)、中部果枝长度(22.63%)、单株铃数(17.64%)变异系数较大,节位数(6.07%)、上半部均长(4.63%)、伸长率(2.59%)变异系数较小;各性状的遗传多样性指数平均值为2.01;相关分析结果表明,陆地棉品质性状与产量性状表现为负相关;主成分分析结果表明,前5个主成分累计贡献率达到71.69%,培育陆地棉优良品种应选择纤维品质优良、结铃数多、株型紧凑、单铃重适中、衣分较高的品种;聚类分析将90份种质分为4个类群,各类群性状差异较大,可为棉花新品种培育提供不同特性的种质材料。     

新疆自育陆地棉品种SSR遗传多样性分析

利用SSR标记对94份新疆自育陆地棉品种的基因组进行分析,研究新疆陆地棉品种的遗传多样性。结果: 从分布于棉花全基因组的206对SSR标记中筛选出54对具有稳定多态性的引物, 共检测出153个多态性位点, 每对引物的等位变异为2~6个,平均为2.93个;基因型多样性(H′)变幅为0.0439–0.7149,平均为0.4491;引物多态信息含量(PIC)为0.0430–0.6640,平均为0.3831。表明SSR标记在品种间可以反映较丰富的遗传多样性信息。94份品种间成对遗传相似系数变幅为0.3846~0.9835, 71.9%的品种相似系数在0.601~0.800内,反映出新疆陆地棉品种间的遗传相似性相对较高。根据UPGMA 聚类分析,在阈值为0.63时,将94份品种划分为2个类群,说明新疆陆地棉品种间遗传关系相对简单,品种的遗传基础相对狭窄,品种遗传组分差异较小,总体上遗传多样性不够丰富;分子聚类结果与品种本身遗传系谱背景和演变趋势吻合度较高,符合品种的真实特性。研究证明,自育品种在分子水平上差异不大,需要努力拓宽品种选育的遗传基础。     

DNA Fingerprint Construction and Genetic Diversity Analysis Based on SSR Markers for Upland Cotton in Xinjiang

[Objective] The aim of this study was to construct a DNA fingerprinting database of 120 upland cotton cultivars from Xinjiang and to analyze their genetic diversity based on SSR markers. [Methods] Seventy-eight evenly distributed SSR primer pairs with high polymorphism and good repeatability were successfully screened out from 586 candidates to construct the fingerprinting database. [Result] A total of 392 alleles from 120 varieties were screened using 78 pairs of core primers, 324 of which were polymorphic loci with a polymorphism rate of 82.7%. Seventeen cultivars had specific genotypes determined using 24 primer pairs and 120 upland cotton cultivars could be identified by only 12 primer combinations. Cluster analysis indicated that genetic similarity coefficient for the 120 upland cotton cultivars ranged from 0.50 to 0.96, with an average of 0.73, indicating that upland cotton resources possess high genetic similarity and have an accordingly narrow genetic basis. [Conclusion] The primer combination method is one of the most effective methods for constructing DNA fingerprinting. The 120 upland cotton varieties were divided into three types with the genetic similarity coefficient matrix; these groups were strongly consistent with their pedigrees.     

QTL Mapping for Yield and Fiber Quality Traits in Double-Cross Population of Chromosome Segment Introgression Lines from Gossypium hirsutum×Gossypium barbadense

[Objective] The aim of this study was to map quantitative traits loci (QTLs) for yield and fiber quality traits in chromosome segment introgression lines (CSILs) from Gossypium hirsutum×Gossypium barbadense. [Method] Four CSILs, MBI 7115, MBI 7412, MBI 7153 and MBI 7346, which were obtained by advanced backcrossing and continuous inbreeding from upland cotton variety CCRI 45 and sea-island cotton variety Hai 1, were used to construct double-cross segregating populations F1 and F1:2 through the following crosses: [(MBI 7115×MBI 7412)×(MBI 7153×MBI 7346)]. Simple sequence repeat (SSR) molecular markers were used to evaluate the genotyes of parents. The F1 and F1:2 populations were used to map QTLs for yield and fiber quality-related traits. [Result] The recovery rates of the recurrent parent CCRI 45 in the four CSILs were all above 97%. Forty-one QTLs, which were distributed across 11 chromosomes, were detected using the two segregating populations. There were 30 QTLs controlling fiber quality with phenotypic variations ranging from 1.11% to 11.80% and 11 QTLs controlling yield-related traits with 1.09%–13.57% phenotypic variations. [Conclusion] Five QTLs for fiber quality were consistently detected in two populations and they were all newly discovered QTLs. This study provides an important theoretical basis for fine mapping of these QTLs and molecular marker-assisted breeding for excellent fiber quality.     

陆地棉种质资源抗旱性状的关联分析

干旱是导致全世界棉花严重减产、纤维品质下降的重要因素,因此获得高产、优质、耐旱的棉花新品种一直是棉花的育种目标。本研究选取217份陆地棉栽培种组成的自然群体为研究对象,采用全生育期处理组灌水量为对照组50%的干旱胁迫处理,并在处理后期对217份材料的株高、衣分、单铃重等18个性状进行2年2点的表型鉴定,干旱胁迫后,群体间响应差异明显,多个表型性状在对照和处理间表现显著差异。通过BLUP分析表型数据并计算各性状的抗旱系数;全基因组范围选取的214对多态性SSR分子标记扫描群体,共检测到393个多态性位点,基因多样性系数平均值为0.402,范围为0.072～0.631, PIC值平均为0.329,范围为0.070～0.560;群体结构分析表明,该群体可分为2个亚群。用上述SSR标记分别对18个性状的抗旱系数进行关联分析,共关联到76个极显著位点(P<0.01),表型变异解释率为2.930%～7.218%,其中共有14个标记位点能同时被2种或以上性状检测到。研究结果可为后期棉花杂交育种亲本选择及抗旱分子标记辅助育种提供理论基础及参考依据。     

Identification and Analysis of Fiber Quality and Yield Related Traits of Interspecific (Gossypium hirsutum L. × G. barbadense L.) Hybrids

[Objective] The aim of this study is to study the hereditary of heterosis of fiber quality and yield-related traits in the upland-island interspecific hybrids, and breed new interspecific hybrid varieties with high yield and fine fiber quality. [Method] In this study, 12 upland cotton materials and 5 sea-island cotton materials were selected to determine the fiber quality and yield traits of their parents and F₁ in Lin’an, Zhejiang and Sanya, Hainan. [Result] It was found that fiber length and fiber strength of F₁ (Gossypium hirsutum × G. barbadense) generally had significant mid-parent heterosis (MPH), some hybrid combinations showed strong over-parent heterosis (OPH), fiber length had a small coefficient of variation between the two places and could be stably inherited. And in terms of yield, seed cotton weight, lint weight, and lint percentage of some upland-island hybrids had MPH, but they were still significantly lower than those of upland cotton parents. [Conclusion] Two long-staple cotton hybrid combinations T035 and T044 with 5A grade high-quality were obtained, and an excellent material of G. barbadense Ta10-280 was screened. This study provides valuable data for the genetic law of fiber quality heterosis of upland-island hybrid cotton.     

棉花DUS测试标准品种的SSR指纹数据库构建

基于SSR核心引物,采用荧光毛细管电泳检测系统与多重PCR技术相结合,构建我国棉花DUS(Distinctness,Uniformity and Stability)测试标准品种的DNA指纹数据库并进行遗传多样性分析。依据多重PCR组合的基本原则与五色荧光检测系统的特点,采用40对核心引物构建了10个4重PCR组合,利用DNA遗传分析仪进行指纹检测与数据采集。40对荧光引物在30份DUS测试标准品种中共扩增产生146个等位变异,每对引物的等位变异数为2~7个不等,平均每对引物产生3.65个等位变异。海7124与陆地棉品种明显划分为2类,来源于新疆的新陆早1号区别于其他陆地棉品种,单独聚为1类。多色荧光检测系统相比常规聚丙烯酰胺凝胶电泳具有高精度、高通量、自动化程度高的优点,尤其适用于大规模指纹数据库的构建,提出了通过构建已知品种DNA指纹数据库,将分子标记技术应用于棉花DUS测试的初步设想。     

Analysis on Competitive Heterosis of Hybrid F1 and F2 between Transgenic Bt Varieties of Upland Cotton

[Objective] The purpose of this study is to supply basis for selecting strong heterosis hybrid and the feasibility of F₂ utilization, by evaluating yield heterosis and fiber quality traits of hybrid F₁ and F₂ generated by transgenic Bt varieties in upland cotton. [Method] Ten upland cotton varieties (lines) with good comprehensive characteristics were selected to produce 10 crosses, and four of them with better competitive heterosis (CH) in yield were screened out to analyze the lint yield and fiber traits of F₁ and F₂. [Result] The results indicated there was a strong CH in yield of F₁, but the yearly variation was large. Hybrids performed better in the poor production year. The CH in yield decreased obviously in most of the F₂ combinations. Further analysis showed that the decrease of boll weight was the main cause of drop of yield CH in F₂. The fiber quality index in F₂ showed a downward trend compared with F₁, and the coefficient of range and variation(CV) increased. The coefficient of variation of quality traits was much lower than that of yield components, with a trend of F₁ < SCRC 28 (CK) and F₂ > F₁. The CH of lint yield and fiber traits changed between F₁ and F₂ in different combinations. We screened out a combination with higher CH of yield in both F₁ and F₂, and with less decreased yield CH, fine fiber quality and light separation in F₂. [Conclusion] The hybrids generated by transgenic Bt varieties in upland cotton characterized by strong adversity resistance and yield stability. Fine fiber quality and light separation in F₂ came from crosses with the parents of fine fiber quality and small differences. So, it is possible for breedersto select valuable F₂ combinations in production.     

利用陆地棉MAGIC群体定位产量、生育期和株高性状的QTL

棉花的产量、生育期和株高是重要的农艺性状, 决定着棉花的经济效益和生产方式。为了研究这些性状的遗传基础, 利用8个亲本构建的包含960个株系的陆地棉MAGIC (multi-parent advanced generation inter-cross)群体和SSR标记对这些性状进行关联分析。对产量、生育期和株高共8个相关性状进行了3年3个地点共5个环境的田间试验。经过最佳线性无偏预测(BLUP)综合多环境的表型数据, 发现MAGIC群体比亲本有更丰富的表型变异。8个性状的广义遗传力(H ²)变化范围为0.17~0.71。结合284个SSR标记基因型数据, 利用混合线性模型对产量、生育期和株高相关性状进行关联分析, 分别检测到51、27和9个显著关联的位点, 这些位点都表现出微效性, 表明该陆地棉MAGIC群体在性状位点的挖掘方面具有高效性。检测到20个标记位点或区间控制多个性状, 还发现单株有效铃数、单铃皮棉重、第一果枝节位和株高存在染色体热点区域, 对多性状综合研究或单性状深入挖掘具有重要价值。本研究为后续深入利用MAGIC群体进行遗传研究提供参考, 一些表型优良的材料和关联到的位点为育种改良奠定了基础。     

1978—2007年中国陆地棉品种主要特性变化趋势

为了研究中国陆地棉品种的遗传性状在不同年代间的变化规律,利用黄河流域、长江流域和西北内陆三大棉区在1978—2007年审定推广的836份陆地棉品种数据库,对陆地棉品种的14个主要农艺经济性状的变化趋势进行分析。结果表明,三大棉区品种的单铃重、皮棉产量和比强度三个性状随着年代变迁,呈明显升高趋势,比强度尤为突出;长江和黄河流域棉区的种植密度随着年代变迁在逐渐降低,而西北内陆棉区的种植密度在增加;叶色、第一果枝节位、铃形、马克隆值和枯、黄萎病抗性在不同年份间波动较大;生育期、衣分、纤维长度在年代间变化平稳,株高20世纪90年代以后变化趋势也较平稳。研究得出1978年以来中国棉花审定推广品种的农艺性状稳定一致且表现良好,产量和纤维品质性状（尤其纤维比强度）有明显改良,在马克隆值和枯、黄萎病抗性方面还有待进一步提高。     

机采棉杂交后代主要株型性状与产量和品质的关系

【目的】从株型、产量及品质众多复杂因素中找出影响机械化生产较大的因素并进行遗传改良,选育适宜机械化生产的高产优质品种,提高棉花育种的效率。【方法】以陆地棉Z571与中棉所49杂交的F2:3群体为研究对象,应用统计软件SAS V8等分析其农艺性状的变异、方差和相关性。【结果】F2:3群体株系材料间农艺性状发生了显著分离,且后代中出现了许多超亲个体,在田间进行选择时要注意农艺性状之间复杂的关系;株高、单株果枝数与单位面积籽棉产量呈极显著正相关;单株果枝数与纤维上半部平均长度、断裂比强度呈极显著负相关,与马克隆值呈现正相关;单株营养枝数与纤维上半部平均长度、断裂比强度呈极显著正相关,与马克隆值呈现显著负相关;产量构成因素中的单位面积铃数与纤维上半部平均长度、断裂比强度呈极显著正相关,与马克隆值呈极显著负相关,铃重和品质性状的相关性与单位面积铃数相反。【结论】株型性状与产量和品质之间均存在显著或极显著的遗传相关;高产高品质的株型特征为单株营养枝数较多;选育高产优质的棉花新品种时要选择铃数较多、铃重较小的材料。     

陆地棉农艺性状与SSR标记的关联分析

利用关联分析方法以160对SSR引物对68份陆地棉品种2个播期组成的自然群体进行基因型检测,在利用STRUCTURE 2.3.4软件分析群体结构的基础上,采用TASSEL 4.0软件的GLM程序和MLM程序对17个农艺性状进行关联分析。结果显示,STRUCTURE群体结构分析将68份供试材料划分为3个亚群,基于Nei's遗传距离的聚类分析也将68份供试材料划分为3个亚群,与群体结构划分结果基本一致。6个SSR位点均能通过GLM和MLM程序检测到,且在2个播期下稳定出现,其中,CER0098-400与全生育期显著关联,DPL0375-250和HAU2414-147与果枝始节显著关联,DPL0504-135、HAU0883-120和NAU1298-524与衣分显著关联。本研究结果为棉花分子标记辅助选择提供了依据。     

Mining Elite Sea-Island Cotton Germplasm Based on Phenotyping and SSR Markers

[Objective] An elite germplasm resource of sea-island cotton with outstanding traits was mined in order to accelerate the breeding process of new varieties. [Method] The core collections of sea-island cotton germplasm consisted of 178 accessions were used as experimental materials in this study. Analyses of variability and diversity were performed through detecting phenotypic data of six main breeding-targeted traits, including boll weight, boll number per plant, lint percentage, fiber length, fiber strength, and micronaire. The elite germplasm of sea-island cotton was selected according to 10% optimal sampling strategy based on the phenotypic value of each trait. The 120 pairs of polymorphic simple sequence repeat (SSR) primers were used to analyze the polymorphism of 178 accessions of the core collections. Then, we conducted the population structure and clustering analysis based on the genotyping results. According to the results of cluster analysis, the primary elite germplasm was further selected, and the final elite germplasm of sea-island cotton was identified. [Result] The results showed that there was a high variability and abundant genetic diversity in the 6 studied traits. In 178 accessions of sea-island cotton, 262 alleles were detected by 120 pairs of SSR primers, with an average of 2.18 loci. The average polymorphism information content (PIC) was 0.067 8-0.630 0, with an average of 0.296 0, showing moderate polymorphism. The cluster analysis showed that the core collection of sea-island cotton was divided into six groups. twenty-three elite germplasm resources of sea-island cotton were identified based on phenotypic value and cluster analysis of SSR markers. [Conclusion] The germplasm of sea-island cotton can be analyzed and evaluated based on the phenotyping and SSR markers, and then the elite germplasm of sea-island cotton can be identified. These results provided the material basis for the genetic breeding of sea-island cotton, as well as the important reference and basis for the mining and identification of crop elite germplasm.     

棉花适宜机采相关性状的SSR标记关联分析及优异等位基因挖掘

棉花机械采收对品种的生育期、株型及对脱叶剂敏感度有较高的要求。本研究利用覆盖全基因组有多态性的214对SSR标记对118份含有一个或多个机采性状的种质资源的株高、始节高、始节位、第一果枝平均长度、生育期及脱叶率6个机采相关性状进行关联分析。利用Structure 2.3.1软件进行群体结构分析,并结合2年2点12个重复的田间表型数据,采用Tassel 5.0软件的混合线性模型MLM关联定位。结果检测到460个等位基因,涉及905个基因型,基因多样性指数平均为0.5151,PIC值平均为0.4587,基因多样性指数和PIC值都大于平均数的标记有99个,占总标记数的46.3%,说明该批SSR标记具有较多的等位变异数和较高的遗传多样性。群体结构分析将118份供试材料划分为4个亚群,结果显示各类群中材料与地理来源无对应关系。关联分析结果显示4种环境中,在显著条件下(P0.05),共检测到124个与6个机采相关性状相关的位点,对表型变异解释率范围为2.23%~14.15%;其中在极显著条件下(P0.01),共检测到20个与机采相关性状相关的位点,对表型变异解释率范围为4.84%~14.15%。基于本研究的结果,鉴定出典型的载体材料11份,分别为系7、金垦9号、Y11、豫棉18、AY-4、K2、朝阳棉2号、DZ22、中棉所43、C2和关农长早B14。以上发掘出的控制棉花适宜机采性状的优异等位基因及优异亲本资源,可为机采棉的分子辅助选择育种提供理论依据。     

陆地棉SSR标记遗传多样性及其与农艺性状的关联分析

分析陆地棉栽培种遗传多样性,通过关联分析寻找与棉花农艺性状相关联的分子标记,为分子标记辅助选择育种和提高棉花育种效率奠定基础。本文采用74个Simple sequence repeat(SSR)标记对172份陆地棉栽培种的基因组变异进行扫描,使用NTSYS-pc 2.20进行聚类,分析该群体遗传多样性;利用Structure 2.3.4软件分析群体结构,在此基础上结合田间表型数据,采用Tassel 2.1的一般线性模型(General linear model,GLM)进行关联分析,定位与农艺性状相关的QTLs。74个标记共检测到148个多态性位点,涉及246个等位变异,变异范围2~7个,平均等位变异数为3.32;引物的多态性信息含量(PIC)为0.0281~0.3733,平均值为0.2370;遗传相似系数变异在0.2816~1,平均值为0.5369,平均遗传相似系数为0.5369,表明我国陆地棉遗传基础狭窄,尽管国外及西北内陆棉区部分材料具有较丰富的遗传变异。聚类分析将该群体划分为12个亚群,不同棉区的材料交叉分布,且聚类结果基本与系谱吻合。群体结构分析却将172份供试材料划分为3个亚群;通过关联分析,发现30个位点与铃重、衣分、黄萎病抗性显著相关(P0.05),各位点对表型变异贡献率为2.24%~5.27%。     

棉花海陆杂交纤维品质性状遗传参数分析

为了研究棉花海陆杂交纤维品质性状的遗传规律,本试验采用5个陆地棉品种（系）作母本与5个海岛棉品种（系）杂交,配制25个杂交组合,随机区组试验设计,重复2次。主要检测杂交种F1代纤维品质性状,以小区平均数进行相应的方差分析及遗传参数估计。结果表明：陆地棉亲本间变异除马克隆值外,其他纤维品质性状均差异显著或极显著,而海岛棉亲本间除伸长率外,其他性状均存在显著或极显著差异;各纤维品质性状双亲互作效应均不显著。另外,遗传参数结果表明：绒长、比强度和马克隆值的遗传变异系数与表型变异系数变化趋势基本吻合,且均大于环境变异系数。整齐度和伸长率的遗传变异系数均小于环境变异系数,说明整齐度和伸长率的变异中环境因素的作用不容忽视。绒长、比强度和马克隆值的广义遗传率较高,在采用海陆杂交改良棉花纤维品质性状时,适宜在早代选择优异株系。     

Genetic mapping of quantitative trait loci for fiber quality and yield trait by RIL approach in Upland cotton

The improvement of cotton fiber quality has become more important because of changes in spinning technology. Stable quantitative trait loci (QTLs) for fiber quality will enable molecular marker-assisted selection to improve fiber quality of future cotton cultivars. A simple sequence repeat (SSR) genetic linkage map consisting of 156 loci covering 1,024.4 cM was constructed using a series of recombinant inbred lines (RIL) developed from an F₂ population of an Upland cotton (Gossypium hirsutum L.) cross 7235 × TM-1. Phenotypic data were collected at Nanjing and Guanyun County in 2002 and 2003 for 5 fiber quality and 6 yield traits. We found 25 major QTLs (LOD ≥ 3.0) and 28 putative QTLs (2.0 < LOD < 3.0) for fiber quality and yield components in two or four environments independently. Among the 25 QTLs with LOD ≥ 3, we found 4 QTLs with large effects on fiber quality and 7 QTLs with large effects on yield components. The most important chromosome D8 in the present study was densely populated with markers and QTLs, in which 36 SSR loci within a chromosomal region of 72.7 cM and 9 QTLs for 8 traits were detected.