利用重组自交系定位棉花第22染色体短臂的纤维品质性状的QTL

 以TM-1的染色体片段代换系CSB22sh和TM-1杂交,构建了包含104个家系的重组自交系（RILs）群体。利用74对具有多态性位点的引物进行检测,构建了包含61个多态性位点,长度为76.93 cM的遗传图谱,平均标记间距离1.26 cM。利用此遗传图谱结合重组自交系群体4个环境下的5个纤维品质性状进行QTL定位,共定位出12个QTLs,解释性状表型变异的2.45%～21.11%;在1,2,3,4个环境中同时检测到的QTLs分别有9,1,1,1个。而利用4个环境平均值进行联合分析定位出个4个QTLs,纤维长度和纤维整齐度的QTLs均为2个,解释性状表型变异的14.37%～19.97%,并且纤维长度和整齐度的QTL在相同的位置。多环境下检测到的QTL可能对标记辅助选择有实际应用价值。     

玉米抗甘蔗花叶病毒QTL的初步研究

以黄早四(抗)×掖107(感)的F2分离群体(184个单株)为作图群体, 构建了具有65个SSR标记位点的遗传连锁图谱, 覆盖玉米基因组1333.3 cM, 标记间平均距离20.5 cM. 通过人工接种鉴定评价184个F3家系对SCMV引起的玉米矮花叶病的抗性反应. 采用复合区间作图法对抗病数量性状位点(QTL)进行定位及遗传效应分析, 结果共检测到3个QTLs,     

短季棉早熟性的分子标记及QTL定位

以两个陆地棉品种中棉所36×TM-1的207个F2单株为作图群体,筛选出73个多态性引物,25个SSR标记、35个RAPD标记和13个SRAP标记,构建了第一张以研究短季棉为主的包含43个标记,标记间的最小遗传距离为11.8 cM,最大遗传距离为48.9 cM,总长1174.0 cM的遗传连锁图谱,覆盖棉花基因组总长度的23.48%。检测到与短季棉早熟性状相关的12个QTLs,其中有8个QTLs呈簇分布在LG1连锁群上,找到对表型变异的贡献率在30%以上与全生育期、霜前花率和开花期有关的QTL各1个。     

陆海高代回交群体抗黄萎病QTL定位

【目的】定位棉花抗黄萎病数量性状位点(Quantitative trait loci, QTL)。【方法】以海7124和TM-1配制抗感组合F1,再以鲁棉研28为轮回亲本构建的137个BC4F1家系为作图群体,筛选出多态性重复序列(Simple sequence repeat, SSR)标记,并与已发表的整合高密度遗传连锁图谱相比对,构建遗传图谱。采用复合区间作图法(Composite interval mapping,CIM)进行大田和病圃两个环境下抗黄萎病QTL定位。【结果】216个多态性SSR位点分布在26条染色体上,可覆盖棉花基因组3 380 cM(centi Morgan),标记间平均距离15.77 cM。定位到6个QTLs,分布在6条染色体上,可解释表型变异8.56%~20.26%,其中5个QTLs与前人研究结果相一致,在第1染色体上新定位到一个QTL。本研究可为分子标记辅助选择抗病育种提供帮助。【结论】定位到6个黄萎病相关QTLs,其中1个是在第1染色体上新发现的QTL。     

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。     

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。     

陆地棉高品质品系纤维品质性状QTL的分子标记及定位

为进一步挖掘利用高品质品系NM03102的优异纤维品质性状的基因,利用陆地棉鲁棉研21作为母本、NM03102为父本构建了F2和F2∶3分离群体。通过7892对SSR引物对亲本进行筛选,获得222对多态性引物,进一步对195个F2群体单株分析得到242个标记位点。其中,182个标记位点连锁构建37个连锁群,共覆盖1661.6 cM,每个连锁群平均包含4.9个标记位点,标记间平均相距9.1 cM,其中35个连锁群被定位到了20条染色体上。利用F2和F2∶3纤维品质数据,通过复合区间作图法,共检测到20个纤维品质性状QTL。其中,1个纤维强度的QTL和1个纤维整齐度的QTL与已有的报道一致,1个纤维强度的QTL和1个麦克隆值的QTL在两世代中稳定存在,这为标记辅助选择奠定了基础。     

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。     

陆地棉花铃期农艺性状QTL定位分析

以陆地棉新陆早35号×益农2号组配的由242个单株构成的F_2群体作为作图群体,利用SSR标记和Joinmap4.0构建了一个遗传连锁图谱。该图谱包含72个标记,分布在20个连锁群上,总长1 286.05 cM,覆盖棉花基因组的29.2%。用完备区间作图法对群体花铃期农艺性状进行了QTL定位分析,共检测到37个QTL位点,株高的7个、始果节高度的2个、节间数的4个、始果节的1个、单叶鲜重的3个、单叶干重的4个、单叶面积的5个、叶绿素含量的2个、单株铃数的9个。通过对棉花重要农艺性状的定位分析,以期找到与这些性状紧密联系的QTL,为今后的育种、分子标记辅助选择和基因克隆提供理论依据。     

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。     

棉花第14染色体分子标记连锁群的构建及其应用

 利用置换系CSB14Sh与TM-1产生F₂分离群体,以SSR标记构建连锁图对置换系进行分子鉴定。利用从覆盖全基因组的3800对引物筛选出的15对多态性引物对群体进行扩增,产生23个分子标记位点。其中,21个分子标记进入了同1个连锁群。通过与前人的分子图谱比较,把该连锁群定位在第14染色体上。表明TM-1与CSB14Sh在第14条染色体上有差异,而在其它染色体上没有差异。再结合染色体置换系构建的过程,可以认为CSB14Sh确实为第14条染色体短臂的置换系。     

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.     

陆地棉背景下海岛棉第18染色体片段置换系的培育及相关农艺性状QTL定位

Sub18是以陆地棉遗传标准系TM-1为背景, 含海岛棉3-79第18染色体的置换系材料。本研究以TM-1为受体亲本, 置换系Sub18为供体亲本, 借助分子标记辅助选择技术培育了一套以TM-1为背景, 含海岛棉3-79第18染色体不同长度片段的置换系。这套置换系由45个株系构成, 共78个置换片段。其中27个株系导入单片段, 占总株系的60%; 9个株系导入2个片段, 占20%; 9个株系导入3个及以上片段, 占20%。导入片段总长度为467.6 cM, 约为该染色体遗传长度的4倍, 每个株系内被替换的染色体片段长度不完全相同, 平均遗传长度为5.99 cM, 最短的为0.9 cM, 最长的20.35 cM。其中13个株系表现开放花蕾性状, 涉及的最短导入片段长5.05 cM。对TM-1、Sub18以及培育的45个导入系进行农艺性状调查和QTL联合定位分析, 鉴定出纤维强度(qFS-C18-1)、整齐度(qFU-C18-1)、马克隆值(qFMi-C18-1)、成熟度(qFMa-C18-1)、皮棉重(qLW-C18-1)、籽指 (qSI-C18-1)和衣分 (qLP-C18-1) 7个加性QTL和5个上位性效应QTL。研究结果为进一步精细定位目标QTL、克隆QTL以及重要性状分子设计育种奠定了基础。     

绿豆遗传连锁图谱的整合

利用绿豆及其近缘种的701对SSR引物,对现有绿豆遗传连锁图谱进行补充,结果在高感豆象绿豆栽培种Berken和高抗豆象绿豆野生种ACC41两亲本间筛选到多态性SSR引物104对。群体分析后,结合其他分子数据,使用作图软件Mapmaker/Exp 3.0b,获得一张含有179个遗传标记和12个连锁群,总长1831.8cM、平均图距10.2cM的新遗传连锁图谱,包括97个SSR标记,91个来自绿豆近缘种;RFLP标记76个;RAPD标记4个;STS标记2个。对32个绿豆、小豆共用SSR标记在遗传连锁图谱的分布分析发现,二个基因组间有一定程度的同源性,共用标记在连锁群上的排列顺序基本上一致,只有部分标记显示绿豆和小豆基因组在进化过程中发生了染色体重排;利用新图谱对ACC41的抗绿豆象主效基因重新定位,仍定位于I(9)连锁群,与其相邻分子标记的距离均小于8cM,其中与右翼SSR标记C220的距离约2.7cM。与原图谱比较,新定位的抗性基因与其相邻标记的连锁更加紧密。     

Genetic effects of nine <Emphasis Type="Italic">Gossypium barbadense</Emphasis> L. chromosome substitution lines in top crosses with five elite Upland cotton <Emphasis Type="Italic">G. hirsutum</Emphasis> L. cultivars

Crosses between Gossypium barbadense L and Gossypium hirsutum L. (Upland cotton) have produced limited success in introgressing fiber quality genes into the latter. Chromosome substitution lines (CSBL) have complete chromosomes or chromosome arms from G. barbadense, line 3-79, substituted for the corresponding chromosome or arms in G. hirsutum in a near isogenic background of TM-1. We top crossed nine CSBL and their parents (TM-1 and 3-79) with five cultivars. Parental lines and their F₂ populations were evaluated in four environments for agronomic and fiber quality traits. The CSBL and their F₂ hybrids showed wide ranges for both agronomic and fiber traits of economic importance. Genetic analysis showed that additive variances were larger than dominance variances for lint percentage, boll weight, lint yield, fiber length, strength, elongation, micronaire, and yellowness; whereas, dominance variances were larger than additive variances only for uniformity of fiber length and equal for fiber reflectance. For all traits, except boll weight and lint yield, significant additive effects of one or more chromosomes from 3-79 in TM-1 background were greater than the corresponding TM-1 chromosome. In addition, we identified specific chromosomes from G. barbadense (3-79) that carry alleles for improvements in specific fiber quality traits in Upland cotton. Favorable additive effects of individual chromosomes or chromosome segments from 3-79 relative to corresponding chromosomes or chromosomes segments from TM-1 were identified in this study as follows: Lint percentage, chromosome/arms 10, 16-15; longer fibers, chromosome/arms 01, 11sh, 26Lo; more uniform fibers, chromosomes/arms 01, 11sh, 10, 17-11; stronger fibers, chromosome/arms 01, 11sh, 12sh, 26Lo, 17-11; fiber elongation, chromosomes/arms 01, 11sh, 26Lo, 10, 17-11; reduced fiber micronaire, chromosome/arms 01, 12sh, 4-15, 16-15, 17-11; fibers with more reflectance, chromosome/arms 10, 4-15, 16-15, 17-11; fiber with less yellowness, chromosome arms 4-15, 17-11. Based on the present study, we concluded that by using CSBL, favorable fiber quality alleles can be introgressed into Upland cotton, thus greatly improving the breeder’s ability for improvement of Upland cotton for a variety of traits. These data should provide useful genetic information to the cotton breeding industry at large.     

Effects of chromosome 5sh from Gossypium barbadense L. on flower production in G. hirsutum L.

Cotton (Gossypium spp.) yield is directly determined by mature bolls that developed from squares and flowers. The first four to six weeks of flowering accounts for the majority of lint yield in upland cotton (G. hirsutum L.) for most cultivated areas of the southern USA cotton belt. In this study, we evaluated 13 cotton chromosome substitution lines (CS-B) and their chromosome specific-F₂ hybrids, TM-1, 3–79, and six cultivars for the number of flowers produced during the first four weeks of flowering. Results showed that CS-B05sh produced more flowers than TM-1 and 3–79 from 10 July to 5 August. The results suggest that when the short arm of chromosome 5 was substituted from 3–79 (G. barbadense L.) into TM-1 (G. hirsutum) a positive genetic association with flower numbers during this flowering period was exhibited. CS-B05sh had comparable flower numbers with three cultivars, Deltapine 90, Phytogen 355, and Stoneville 474 and more flowers than, Sure Grow 747, Sure Grow 125, and Deltapine 5415. Different patterns for additive and dominance effects on cumulative flowers were observed across weeks of flowering. Dominance effects were more apparent during the early part of the flowering period while additive effects were more apparent towards the end of the flowering period.     

YM型小麦温敏雄性不育系不育基因的QTL定位

YM型小麦温敏雄性不育系的不育基因被定位在1Bs染色体片段上, 但已发现的相邻分子标记与该基因的遗传距离较大, 达10 cM以上。为寻找与该基因连锁更紧密的分子标记, 以YM型温敏雄性不育系ATM3314与恢复系中国春杂交的F₂代200株为作图群体, 从1Bs的22个SSR引物中筛选出5个在亲本和F₂代中分离的SSR引物, 构建了1个包含5个标记的1Bs局部遗传连锁图谱。结合F₂代个体的育性调查, 采用复合区间作图法在YM型温敏雄性不育系的1Bs染色体上检测到不育基因的1个主效QTLrfv1-1和1个微效QTLrfv1-2。rfv1-1位于SSR标记Xgwm18和Xwmc406之间, 与两标记的遗传距离分别为6.0 cM和4.6 cM, LOD值为8.80, 加性效应23.87, 显性效应10.44, 可解释表型变异的23.91%; rfv1-2位于Xwmc406和Xbarc8之间, 与两标记的遗传距离分别为4.0 cM和3.4 cM, LOD值为3.10, 加性效应17.59, 显性效应5.99, 可解释表型变异的7.78%。本研究初步定位了YM型小麦温敏雄性不育系1Bs染色体片段上不育基因的QTL, 为进一步准确定位该基因奠定了基础。