QTL Mapping of Boll Weight Trait Based on Recombinant Inbred Lines in Gossypium hirsutum L.

[Objective] The aim of this study was to explore the quantitative trait locus (QTL) related to the boll weight. [Method] A single seed descended population of 137 recombinant inbred lines (RILs) was developed from the cross of upland cotton (Gossypium hirsutum L.) CCRI 36 and G2005, an introgression inbred line introgressed from G. barbadense. Using restriction-site associated DNA sequencing (RAD-seq), a genetic linkage map composed of 6 434 makers, including 6 295 single nucleotide polymorphisms (SNP) and 139 simple sequence repeat (SSR) markers, was developed from the RILs population. [Result] This map spanned 4 071.98 cM with an average distance of 0.63 cM between adjacent markers. QTL mapping was performed by using boll weight data of five environments through WinQTLCart 2.5 software. Thirty-two QTL, with 4.46%-15.84% explained phenotypic variation related boll weight, were detected and found distributing on 15 chromosomes. qBW-A4-1, qBW-A4-2, qBW-A5-2, qBW-D9-1, and qBW-D9-2 were detected in two environments, which explained 5.07%-15.84% of the phenotypic variation. [Conclusion] Major QTLs detected in this study will provide an important reference for analysis of the genetic mechanism of boll weight.     

QTL Mapping of Important Agronomic Traits on Chromosomes Showing Marker Segregation Distortion in Interspecific Backcross Cotton Populations

[Objective] The purpose of this study was to map QTLs for yield, maturity, and fiber quality traits of cotton interspecific hybrid populations and to mine favorable alleles from the cotton genome for QTL fine mapping, gene cloning, and molecular marker-assisted selection. [Method] Four BC₁F₁ populations, E(E3), E(3E), (E3)E, and (3E)E, were developed by crossing sea island cotton 3-79 ("3") and upland cotton 'Emian 22' ("E"), and with "Emian 22" as the recurrent parent. BC1F2 populations derived from BC1F1 populations were phenotyped to allow mapping of QTLs for yield-, maturity-, and fiber quality-related traits on chromosomes showing segregation distortion. [Result] A normal distribution test indicated that six fiber quality-related traits, except for the micronaire value in E (E3) and the short fiber ratio in all populations, followed a normal distribution pattern; in contrast, earliness-related traits were not normally distributed in all populations, which suggests that genotype-environment interactions have strong effects on maturity-related traits. Using composite interval mapping, 47 QTLs were detected on three chromosomes (2, 16, and 18): 15 in (E3)E, 13 in (3E)E, 12 in E(E3), and 7 in E(3E), with the phenotypic variation explained (PVE) ranging from 8.8%–30.9%. A total of 27 fiber-related QTLs were discovered, with the PVE ranging from 9.0%–30.9%. Five yield-related QTLs (PVE = 8.8%–17.4%) and 13 maturity-related QTLs (PVE = 9.4%–19.4%) were also identified. [Conclusion] Comparison analysis showed that most QTLs in our study were consistent with the MetaQTL, including QTLs for boll weight, fiber length, fiber length uniformity, lint percentage, and micronaire value on chromosome 2; QTLs for fiber length, fiber strength, and fiber length uniformity on chromosome 16; and QTLs for boll weight, date of boll opening, fiber length, fiber strength, fiber length uniformity, and micronaire value on chromosome 18. Several detected QTLs in our study were not found in the MetaQTL, such as QTLs for date of boll opening and lint percentage on chromosome 16 and a QTL for the date from seedling to flowering stages on chromosome 18. These newly identified QTLs may provide novel insights for cotton QTL analysis.     

陆地棉株型及生育期相关性状QTL定位

[目的]为了深入分析棉花株型及生育期相关性状的分子遗传机制,加速适机采棉花新品种分子标记辅助育种进程.[方法]通过构建包含413个单株的F2群体,结合高密度SNP(Single nucleotide polymorphism,单核苷酸多态性)遗传图谱,开展株高(Plant height,PH)、第一果枝节位(Node ...     

多环境下陆地棉(Gossypium hirsutum L.)重组自交系铃重与衣分性状的QTL分析

本研究利用以SGK9708为母本,0-153为父本构建的196个陆地棉重组自交系(F6:8)构建了包含186个标记,总长827.84 cM,标记间平均距离4.45 cM,覆盖棉花基因组18.6%的遗传连锁图谱,并对7个环境下的铃重和衣分性状进行QTL定位和上位性互作分析.利用两种分析软件(WinQTLcart2.5和Q...     

Mapping of Verticillium Wilt Resistance QTL with Interspecific Advanced Backcross Population between Upland Cotton (Gossypium hirsutum L.) and Sea-Island Cotton (G. barbadense L.)

[Objective] The aim of this study was to map quantitative trait loci (QTLs) of Verticillium wilt resistance in cotton. [Method]In this study, with the cultivar Lumianyan 28(Gossypium hirsutumL.) as the recipient parent and the F₁generation obtained from the cross Hai7124 (G. barbadense) and TM-1(G. hirsutumL.) as the donor parent, an interspecific advanced backcross population was constructed. Compared with the integrated high density genetic linkage map published, simple sequence repeat(SSR) markers of polymorphism were used to construct genetic linkage map. QTLs detection was conducted by composite interval mapping method in field and disease nursery. [Result] 216 simple sequence repeated (SSR) markers of polymorphism were assigned to 26 Chromosomes with a total map distance of 3 380 cM and an average distance of about 15.77 cM between two adjacent markers. Six QTLs located on 6 chromosomes had been detected and could explain phenotypic variance with 8.56%～20.26%. Five of Six QTLs were consistent with the previous study. Moreover, one novel QTL which located on Chromosome 1 was detected in this study. These results maybe helpful for the marker-assisted development of new cultivars which were resistant to Verticillium wilt. [Conclusion] Six QTLs were detected, one of them is a new QTL on chromosome 1.     

毛棉苗期抗旱性状的QTL定位

【目的】通过分析毛棉苗期抗旱相关性状的数量性状位点(Quantitative trait locus,QTL),以期检测稳定的主效QTL,促进栽培品种抗旱性状遗传改良及提高抗旱育种效率。【方法】以四倍体野生种毛棉(Gossypium tomentosum)和陆地棉品种中棉所12(CCRI 12)的种间杂种F2及其F2:3家系为研究材料,用于基因型分型的F2有188个系,用于表型分型的F2:3家系有149个株系。分别在干旱胁迫和正常灌水2个环境下调查表型数据。采用复合区间作图法对F2:3家系苗期相关性状抗旱系数进行QTL定位。【结果】对苗期相关性状抗旱系数的QTL定位分析,共得到16个QTL,其中与株高、叶片数、叶绿素含量、脯氨酸含量、丙二醛含量抗旱系数相关的QTL分别有5个、1个、3个、3个、4个,分布在13条染色体上。来自毛棉的5个加性QTL分别为qSHDC-19-1、qSHDC-19-2、qSLNDC-5-1、qMDADC-24-1、qMDADC-24-2,其加性效应值为0.10~0.22,解释变异9.4%~25.8%。【结论】这些与抗旱相关的QTL有助于棉花抗旱分子标记辅助选择。     

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.     

陆地棉产量相关性状的QTL定位

中棉所28和湘杂棉2号分别是以中棉所12×4133和中棉所12×8891配制而成的两个陆地棉强优势杂交种。以其F₂为作图群体,筛选6000多对SSR引物,利用两群体间27个共有多态位点,通过JoinMap 3.0软件整合了一张包含245个多态位点、全长1847.81 cM的遗传图谱。利用Win QTLCart 2.5复合区间作图法分别对两群体8个产量相关性状在F₂和F_2:3中进行QTL定位,在中棉所28群体多环境平均值的联合分析中检测到16个QTL,三环境分离分析中检测到43个QTL;在湘杂棉2号群体分别检测到20个和66个QTL。在A3、D8、D9等染色体上有QTL成簇分布现象,同时在两个群体中发现一些不受环境影响且稳定遗传的QTL。对考察的8个性状在两个群体中发现12对共有QTL,控制果枝数、衣分和籽指的QTL增效基因位点均来源于共同亲本中棉所12。综合分析推测中棉所12的育种价值主要是通过提高后代的结铃性来实现的。研究结果为棉花产量性状的分子设计育种提供了有用的信息。     

基于两个陆地棉低世代群体定位纤维品质相关QTL

【目的】定位棉花纤维品质性状相关的数量性状位点(Quantitative trait locus,QTL)。【方法】以陆地棉高强纤维品系中棉所679和纤维品质一般的农垦5号为亲本构建包含200个单株的F2群体及对应的F2:3家系群体,对2个群体的纤维长度、断裂比强度等5个纤维品质性状进行检测。用6 688对简单重复序列(Simple sequence repeat, SSR)引物在双亲间筛选,得到149对多态性引物,以F2为作图群体,使用QTL IciMapping软件进行连锁图谱构建,并对F2及F2:3群体进行QTL定位。【结果】根据F2群体基因型信息构建了1张包含119个标记、28个连锁群、总长为1 173.5 cM(centiMorgan)的遗传连锁图谱。分别在F_2、F2:3群体中检测到9个和11个与纤维品质性状相关的QTLs,这些QTLs分布在11个连锁群上。其中F2群体的qFL-D11-1、q BT-D11-1与F2:3群体的qFL-D11-1、q MIC-D11-1均定位在标记DPL0062与HAU0423之间,推测这些位点可能是控制纤维品质性状的重要QTL。【结论】利用多个群体进行QTL定位有益于发现稳定的QTL位点,控制纤维品质性状的基因可能成簇存在,为挖掘纤维品质性状相关基因及分子标记辅助育种奠定基础。     

棉花叶绿素含量和光合速率的QTL定位

 为了探讨棉花光合作用及相关生理性状的遗传规律, 利用四交分离作图群体泗棉3号/苏12//中4133/8891的273个F_2：3家系为材料,用MAPQTL5.0软件及区间作图方法(IM), 对棉花叶绿素含量及光合速率进行了QTL分析。检测到3个与叶绿素含量相关的QTL, 分别位于染色体D6、D8和A10, 解释性状表型变异的4.3%, 4.5% 和5.2%。检测到3个与光合速率相关的QTL, 位于D5、D6和A11染色体, 解释性状表型变异的3.8%,7.4% 和8.4%。两个性状所有QTL的遗传效应均以加性效应为主。本研究定位的棉花叶绿素含量和光合速率QTL均是首次报道,可尝试应用于高光效育种的分子标记辅助选择。     

中棉所70分离群体农艺性状相关QTL定位

【目的】定位棉花产量相关性状的数量性状基因座(Quantitative trait locus,QTL)。【方法】以中棉所70的F_2分离群体为遗传作图群体,利用从14 820对简单序列重复(Simple sequence repeat,SSR)引物中筛选出的267对两亲本间的多态性引物检测F_2群体250个单株的标记基因型,利用Joinmap 4.0进行连锁分析,并通过WinQTLCart 2.5复合区间作图法对F_(2:3)群体的株高、单株结铃数和单株果枝数性状进行QTL定位。【结果】在F_2群体中共获得342个SSR标记位点,并构建了包括312个标记、35个连锁群,总长1 929.9 cM的遗传连锁图谱(标记间平均距离为9.2 cM,覆盖棉花基因组的43.4%)。经QTL定位,共检测到19个QTL,其中涉及株高的7个、单株果枝数4个、单株结铃数8个,这些QTL分布在8条染色体上,解释0.25%~11.28%的表型变异。【结论】这些与农艺性状相关的QTL有助于棉花产量分子标记辅助选择。     

陆地棉衣分差异群体产量及产量构成因素

 以衣分差异较大的陆地棉品种为材料,构建了包含188个F₂单株的作图群体,应用6111对SSR引物对亲本进行了分子标记筛选,结果仅获得了123个多态性位点,其中88个位点构建了总长为666.7 cM、平均距离为7.57 cM的遗传图谱,覆盖棉花基因组的14.9%。通过复合区间作图法对F₂单株和F_2∶3家系进行QTL检测,共鉴定出了18个控制产量及产量构成因素变异的QTLs,包括2个衣分QTLs、4个子棉产量QTLs、4个皮棉产量QTLs、2个衣指QTLs、3个单株铃数QTLs、2个铃重QTLs和1个子指QTL。 解释的表型变异分别为\{6.9%\}～16.9%、5.6%～16.2%、4.8%～15.6%、7.7%～13.3%、8.2%～11.6%、6.1%～7%和6.6%。不同QTLs在相同染色体区段上的成簇分布表明与产量性状相关的基因可能紧密连锁或一因多效。产量及产量构成因素QTLs的遗传方式主要以显性和超显性效应为主。检测到的主效QTLs可以用于棉花产量及产量构成因素的分子标记辅助选择。     

海岛棉CSSLs分子评价及纤维品质、产量性状QTL定位

本课题组前期以陆地棉中棉所8号(CCRI8)为轮回亲本, 海岛棉Pima 90-53为供体亲本培育了一套陆地棉中棉所8号为背景的海岛棉染色体片段置换系(CSSLs), 本研究利用SSR标记对该置换系群体BC₃F₅进行基因型检测, 在3个不同环境下(河北保定、青县和新疆轮台)鉴定其纤维品质和产量相关性状并进行QTL定位。该置换系群体包含182个家系, 置换片段数在1~15个之间, 平均为6.6个; 导入片段长度在0.7~83.2 cM之间, 平均长度为16.8 cM; 置换片段总长度20 249.6 cM; 背景回复率在92.3%~99.6%之间, 平均为96.2%。共检测出59个相关的QTL, 其中与纤维品质性状相关的41个, 单个QTL的贡献率为1.27%~26.66%; 与产量性状相关的18个, 单个QTL的贡献率为2.03%~19.38%; 检测到14个稳定的QTL, 其中4个马克隆值和2个纤维伸长率相关的稳定QTL增效基因均来自高值亲本海岛棉Pima 90-53, 2个铃重相关的稳定QTL增效基因来自高值亲本陆地棉中棉所8号。研究结果为深入开展纤维品质和产量性状的QTL精细定位、QTL间互作和分子育种提供了理论依据。     

Hyperspectral Models for Estimating SPAD Value of Cotton Leaves under Waterlogging Stress

[Object] To setup the hyperspectral sensing models for estimating SPAD value of cotton leaves under waterlogging stress. [Method] Irrigation and drainage controllable plots were introduced to simulate the waterlogging stress treatment in the flowering and boll forming stage, during which the change characteristics of the cotton leaf spectral reflectance and SPAD value were observed after 1 d, 3 d, 6 d, 9 d waterlogging, respectively. To find out the hyperspectral sensing models for estimating SPAD value of cotton leaves under waterlogging stress, the correlation and regression relationships between SPAD value and spectrum parameters were analyzed. [Result] (1) The SPAD value of the fourth cotton leaf from the top was significantly lower than control when suffers from waterlogging for 3 d, when waterlogged 9 d the SPAD value decreased by around 15% compared with the control. (2) The cotton suffering from waterlogged damage in the flowering and boll forming stage caused the reflection peak in green light wave band became steep, while the near infrared spectral reflectance increased, and caused the reduction of red absorption and red edge position "blue shifts", the red edge position drifts towards short wave with 4～5 nm when suffers from waterlogging for 9 d. With increase of the waterlogged days, the red edge slope and red edge area increased with a maximum value at 6 d of waterlogging, meanwhile, the skewness and kurtosis of red edge increased. (3) After waterlogging, the SPAD value of the fourth cotton leaf from the top (chlorophyll content) had a remarkable correlation with red edge slope(Dr), red edge position(λr), green peak reflection(Rg), green peak position(λg), red well position(λo), blue edge area(SDb), yellow edge skewness(Sy), yellow edge kurtosis(Ky), red edge skewness(Sr), red edge kurtosis(Kr), etc. An experience linear, polynomial and exponential models for estimating SPAD value had been built through using the Sy, Sr, Kr as independent variables, respectively, their determination coefficient (R²) were greater than 0.9, and the root mean square error (RMSE) were less than 1; and an experience binary linear regression equation for estimating SPAD value had been built through multivariate regression using the λg, SDr/SDb(VI3), Sb, Sy, Ky as independent variables, the R² was as high as 0.973, and the RMSE was 0.393. [Conclusion] The model can be remote sensing model used as estimating leaf SPAD of cotton value under waterlogging stress.     

水稻叶片保绿相关性状的QTL分析

以籼稻窄叶青8号（ZYQ8）与粳稻京系17（JX17）为亲本的DH群体为材,考察叶片保绿相关性状,并利用该群体的分子连锁图谱进行QTL分析。共检测到7个与水稻叶片保绿有关的QTL,包括与黑暗下保绿面积相关的3个QTL,位于第1、6和8染色体上,贡献率分别为11.07%、10.31%和11.21%;与黑暗下保绿程度相关的2个QTL,位于第1和12染色体     

陆地棉光合相关性状的QTL定位分析

光合作用是棉花产量的主要物质来源。本研究以高光效陆地棉冀优861和低光效陆地棉新陆早25号为亲本组配的196个F₂单株为作图群体,利用SSR（Simple Sequence Repeat）标记构建陆陆杂交遗传连锁图谱,共有30个标记位点连锁,包含4个连锁群,全长244.4cM。利用QTL IciMapping 4.1软件的完备区间作图法对冀优861×新陆早25号F_2:3家系的光合相关性状进行QTL作图分析,共定位到光合相关5个性状的10个QTLs,其中1个光合速率QTL和1个胞间CO₂浓度QTL分别定位在D3和D7染色体上。本研究为棉花光合相关性状QTL的精细定位及分离克隆打下基础,为聚合棉花高光效分子标记辅助育种提供理论依据。     

QTL mapping for economic traits based on a dense genetic map of cotton with PCR-based markers using the interspecific cross of Gossypium hirsutum × Gossypium barbadense

A high-density molecular marker linkage map of cotton based entirely on polymerase chain reaction-based markers is useful for a marker-assisted breeding program. Four kinds of markers—simple sequence repeats (SSRs), sequence-related amplified polymorphism (SRAP), random amplified polymorphic DNA (RAPD), and retrotransposon-microsatellite amplified polymorphism (REMAP)—were used to assay an F₂ population from a cross between “Handan208” (Gossypium hirsutum) and “Pima90” (Gossypium barbadense). Sixty-nine F₂ plants were used for map construction using 834 SSRs, 437 SRAPs, 107 RAPDs, and 16 REMAPs. Linkage analysis revealed that 1,029 loci could be mapped to 26 linkage groups that extended for 5,472.3 cM, with an average distance between 2 loci of 5.32 cM. The corresponding 69 F_2:3 families were grown, arranged in two replicates, and scored for eight phenotypes. Quantitative trait loci (QTL) analysis was performed by means of composite interval mapping using WinQtlCart ver 2.0. A total of 52 distinct QTLs were detected: 4 QTLs for lint index, 8 for seed index, 11 for lint yield, 4 for seed cotton yield, 9 for number of seed per boll, 3 for fiber strength, 5 for fiber length, and 8 for micronaire value. The present map and QTL analysis may provide a useful tool for breeders to transfer desirable traits from G. barbadense to the mainly cultivated species, G. hirsutum.     

Construction of a genetic linkage map and QTL analysis of fiber-related traits in upland cotton (Gossypium hirsutum L.)

A genetic linkage map with 70 loci (55 SSR, 12 AFLP and 3 morphological loci) was constructed using 117 F₂ plants obtained from a cross between two upland cotton cultivars Yumian 1 and T586, which have relatively high levels of DNA marker polymorphism and differ remarkably in fiber-related traits. The linkage map comprised of 20 linkage groups, covering 525 cM with an average distance of 7.5 cM between two markers, or approximately 11.8% of the recombination length of the cotton genome. The present genetic linkage map was used to identify and map the quantitative trait loci (QTLs) affecting lint percentage and fiber quality traits in 117 F_2:3 family lines. Sixteen QTLs for lint percentage and fiber quality traits were identified in six linkage groups by multiple interval mapping: four QTLs for lint percentage, two QTLs for fiber 2.5% span length, three QTLs for fiber length uniformity, three QTLs for fiber strength, two QTLs for fiber elongation and two QTLs for micronaire reading. The QTL controlling fiber-related traits were mainly additive, and meanwhile including dominant and overdominant. Several QTLs affecting different fiber-related traits were detected within the same chromosome region, suggesting that genes controlling fiber traits may be linked or the result of pleiotropy.     

棉花上部叶片叶绿素SPAD值动态变化研究

为了探索利用叶绿素SPAD值在不同生育阶段进行棉花营养诊断的方法,以2个早熟品种（‘中棉所36’、‘中棉所50’）和2个中熟品种（‘中棉所41’、‘鲁棉28’）为对象,研究了棉花主茎倒1至倒4叶在全生育期的叶绿素SPAD值动态变化,并研究了氮、磷施用量对鲁棉28蕾期、花期和吐絮期主茎功能叶的SPAD值影响。结果表明：2个早熟品种的棉花主茎叶全生育期SPAD值呈现倒一叶<倒二叶<倒三叶<倒四叶的规律,2个中熟品种在盛铃期以前主茎4片叶SPAD值也呈现和早熟品种一样的规律,但盛铃期以后SPAD值叶序变化不规则。在吐絮前,棉花主茎倒四叶SPAD值可以作为棉株营养诊断的参考,早熟品种棉花主茎倒一叶或倒二叶吐絮前10天和吐絮后10天左右的SPAD差值大小可以作为棉株衰老程度的参考值,中熟品种棉花主茎倒三叶吐絮前15天和吐絮后15天左右的SPAD差值大小可以作为棉株衰老程度的参考值。本试验条件下,纯氮用量高于270 kg/hm2,吐絮期主茎功能叶SPAD值与不施氮处理差异极显著,高氮处理利于主茎功能叶在吐絮期维持较高的SPAD值;纯P2O5用量在120 kg/hm2即能使吐絮期主茎功能叶维持较高的SPAD值,增加磷肥用量SPAD值反而下降。     

利用重组自交群体检测水稻抗亚铁毒胁迫的QTLs

潜育性水稻田广泛分布于中国、斯里兰卡、印度、印度尼西亚、塞拉里昂、利比亚、尼日利亚、哥伦比亚和菲律宾等国，其中我国南方稻区就有670万公顷低产潜育性水稻田。该类水稻田还原性强，矿质营养失调，尤以Fe2+ 过量积累，对水稻生长发育产生不良的逆境胁迫作用。培育抗亚铁毒的水稻品种是简便、经济有效地提高稻谷产量的重