陆地棉转录因子的染色体定位

利用植物转录因子PTFD数据库1 116条陆地棉转录因子DNA序列设计的1 455对SSR引物,筛选陆地棉品种/品系渝棉1号、中棉所35、7235和T586,获得66对多态性引物。它们涉及到27个转录因子家族的64个转录因子,其中渝棉1号与中棉所35间23对多态性引物,渝棉1号与T586间30对多态性引物,渝棉1号与7235间33对多态性引物。以多态性引物检测对应重组近交系群体,共获得93个位点。其中,(渝棉1号×中棉所35)群体23个位点,(渝棉1号×T586)群体32个位点,(渝棉1号×7235)群体38个位点。利用转录因子SSR位点与实验室已定位的SSR位点进行遗传连锁分析,将84个位点定位于23条染色体上,其中32个位点分布于A染色体组,52个位点分布于D染色体组。     

基于EST-SSR的木薯分子标记遗传连锁图谱的构建

此实验以木薯推广品种‘KU50’为母本,‘SC124’为父本通过杂交得到包含240个单株的F1分离群体,利用300对EST-SSR引物,20对SSR和20对SRAP引物组合对亲本和部分群体株系进行多态性分子标记筛选,共获得具有多态性的引物110对。在此基础上,利用这110对多态性引物对该F1群体进行分子标记的多态性分析,共获得269个多态性标记。利用JoinMap 3.0软件对这269个多态性标记进行分组和遗传图谱构建,最后获得了一张包含140个标记的木薯分子遗传连锁图谱,其中EST-SSR标记111个,SSR标记22个,SRAP标记7个;共21个连锁群,其中连锁群1和3（LG1、LG3）上的标记位点最多（15个）,LG21标记位点最少（2个）。此遗传连锁图谱的总长度为1314.775 cM,单个连锁群最长为132.904 cM（LG3）,最短为0.431 cM（LG19）,标记间平均长度9.391 cM。     

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。     

甜菜遗传连锁图谱初步构建

以甜菜高产低糖型JV34-2和低产高糖型2B023两材料杂交, 构建了200个单株的F₂作图群体, 利用所筛选出的56对SRAP引物组合和20对SSR引物, 对F₂作图群体进行PCR扩增和遗传连锁分析, 初步构建了一张包含9个连锁群、141个(123个SRAP和18个SSR)标记位点的甜菜遗传连锁图谱。该图谱覆盖长度为1399.88 cM, 平均图距9.92 cM。未进入连锁群的有4个标记。9个连锁群包含3~26个标记不等, 连锁群遗传距离15.69~237.21 cM。连锁群上有20.56%的标记出现偏分离, 主要集中在Ch3连锁群上, 其余分散在Ch1、Ch2、Ch8和Ch9中。该图谱是我国甜菜领域利用SRAP和SSR相结合方法, 构建的第一个较精密的分子遗传图谱, 为重要性状的基因定位和优良基因的克隆奠定了基础。     

新疆海岛棉SSR分子标记遗传连锁图谱的构建

本研究以海岛棉品种新海3号及吉扎82为亲本构建的190个F2:3家系为材料,利用SSR分子标记构建了新疆海岛棉的遗传连锁图谱,为海岛棉分子标记辅助选育提供帮助。其主要研究如下:用从4 886对棉花SSR引物中筛选获得的双亲间多态性明显且重复性好的107对SSR引物对海岛棉(新海3号×吉扎82)F2群体进行基因型鉴定,共得120个稳定的SSR多态性位点,多态性频率为2.4%。初步构建了一个包含22个连锁群,74个标记,总长893 c M,覆盖海岛棉基因组20.10%的分子标记遗传连锁图谱。该图谱标记平均间距12.06 c M,最大图距54 c M,最小为1 c M,平均每个连锁群的标记数是3.4个。     

‘新世纪梨’ב崇化大梨’F1代分子遗传连锁图谱的构建

本研究目的在于为以后控制重要农艺性状的QTL定位、梨分子标记辅助育种及品种改良提供基础理论。利用‘新世纪梨’ב崇化大梨’杂交得到的210株F₁代实生苗为作图群体,对分离群体进行了ISSR、SRAP、SSR标记的多态性检测,共得到154条多态性条带,其中偏离孟德尔遗传比例的含21.4%(P<0.01)。应用JoinMap 4.0软件对154个多态性条带进行遗传连锁分析,构建了一张包括9个SSR标记,79个SRAP标记,8个ISSR标记,合计96个标记分属于14个连锁群的遗传图谱,图谱总长度为1530 cM,平均图距为16.1 cM,最大的连锁群含有64个标记,最小遗传距离小于0.1 cM。

     

亚麻遗传连锁图谱的构建

利用DIANE (纤用亚麻栽培种)和宁亚17 (油用亚麻栽培种)为杂交亲本,构建30个F₂单株作为作图群体,选用71对SRAP和24对SSR共显性标记构建了全长为546.5 cM,含12个连锁群(LGs)的亚麻遗传连锁图谱,标记均匀分布于12个连锁群,每个连锁群有4~15个标记,标记间平均距离为5.75 cM。结果表明,SRAP标记和SSR标记中共显性标记适合于亚麻遗传连锁图谱的构建,但该图谱覆盖的基因组范围较小,需继续图谱的完整性工作。本研究为今后的亚麻在分子生物学方面的研究提供了基础信息。     

烟草SRAP和ISSR分子遗传连锁图谱构建

采用烤烟品种台烟7号与白肋烟品种白肋21杂交,构建了187个单株的F₂遗传作图群体,利用所筛选的68个能扩增出多态性条带的SRAP和ISSR引物,对F₂作图群体进行PCR扩增和遗传连锁分析,初步构建了一张包含26个连锁群、112个(92个SRAP和20个ISSR)标记位点的烟草遗传连锁图谱。该图谱覆盖长度为1 560.2 cM,平均图距18.1 cM。有16个标记未进入连锁群。26个连锁群包含2~20标记不等,连锁群遗传距离0~291.0 cM。连锁群上有24.1%的标记出现偏分离,主要集中在LG1和LG4连锁群上,其余分散在不同连锁群。该图谱为烟草重要农艺性状的基因定位、以及分子标记辅助选择等研究奠定基础。     

应用SRAP、ISSR和TRAP标记构建金针菇分子遗传连锁图谱

本研究应用金针菇(Flammulina filiformis)的两个菌株,黄色金针菇Y1701和白色金针菇W3082为作图亲本,采用分子标记以构建高密度的金针菇分子遗传连锁图谱。通过F1代产生的71个单孢为遗传连锁图谱作图群体,应用SRAP、ISSR和TRAP标记引物,利用PCR对得到的作图群体进行多态性分析,构建了一张拥有11个连锁群以及125个标记位点,总长度860.3 cM的遗传连锁图谱。连锁群平均长度为78.21 cM,最长的连锁群为132.9 c M,最短的连锁群为16.3 c M。多态性标记间最大遗传距离为38.4 cM,最小距离为0.5 cM,连锁图中出现了6个大于20 cM的间隙,标记密度6.88 cM,是迄今以来金针菇遗传连锁图谱相关研究中密度最高的。本研究所获得的高密度遗传连锁图谱有助于金针菇QTL定位,分子辅助育种和基因定位的研究。     

陆地棉遗传图谱构建及产量和纤维品质性状QTL定位

利用3 458对SSR引物筛选陆地棉中棉所35和渝棉1号间的多态性引物, 获得173对。以多态性引物检测(渝棉1号×中棉所35)F₂群体180个单株的标记基因型, 共获得178个标记位点。构建的遗传连锁图谱包括148个标记, 36个连锁群, 总长1 309.2 cM, 标记间平均距离8.8 cM, 覆盖棉花基因组的29.5%。36个连锁群中的28个分别被定位于20条染色体, 8个连锁群未定位于染色体。以渝棉1号×中棉所35的F₂、F_2:3群体的产量、纤维品质性状鉴定结果, 利用区间作图方法, 检测到4个产量性状QTL, 即2个衣分(LP)、1个铃重(BW)、1个籽指(SD); 5个纤维品质性状QTL, 即1个纤维长度(FL)、2个纤维比强度(FS)和2个纤维细度(FF)。LP1、BW、SD、FL和FS1被定位于第7染色体, LP2、FS2、FF1和FF2被分别位于第15、21、9和20染色体。5个纤维品质QTL的有利等位基因均来源于渝棉1号。     

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.     

Linkage map construction and mapping QTL for cotton fibre quality using SRAP, SSR and RAPD

Tetraploid cotton is one of the most extensively cultivated species. Two tetraploid species, Gossypium hirsutum L. and G. barbadense L., dominate the world's cotton production. To better understand the genetic basis of cotton fibre traits for the improvement of fibre quality, a genetic linkage map of tetraploid cotton was constructed using sequence‐related amplified polymorphisms (SRAPs), simple sequence repeats (SSRs) and random amplified polymorphic DNAs (RAPDs). A total of 238 SRAP primer combinations, 368 SSR primer pairs and 600 RAPD primers were used to screen polymorphisms between G. hirsutum cv. Handan208 and G. barbadense cv. Pima90 which revealed 749 polymorphic loci in total (205 SSRs, 107 RAPDs and 437 SRAPs). Sixty‐nine F₂ progeny from the interspecific cross of ‘Handan208’בPima90’ were genotyped with the 749 polymorphic markers. A total of 566 loci were assembled into 41 linkage groups with at least three loci in each group. Twenty‐eight linkage groups were assigned to corresponding chromosomes by SSR markers with known chromosome locations. The map covered 5141.8 cM with a mean interlocus space of 9.08 cM. A × test for significance of deviations from the expected ratio (1: 2: 1 or 3: 1) identified 135 loci (18.0%) with skewed segregation, most of which had an excess of maternal parental alleles. In total, 13 QTL associated with fibre traits were detected, among which two QTL were for fibre strength, four for fibre length and seven for micronaire value. These QTL were on nine linkage groups explaining 16.18‐28.92% of the trait variation. Six QTL were located in the A subgenome, six QTL in the D subgenome and one QTL in an unassigned linkage group. There were three QTL for micronaire value clustered on LG1, which would be very useful for improving this trait by molecular marker‐assisted selection.     

T1 locus in cotton is the candidate gene affecting lint percentage, fiber quality and spiny bollworm (Earias spp.) resistance

A genetic linkage map of chromosome 6 was constructed by using 270 recombinant inbred lines originated from an upland cotton cross (Yumian 1 × T586) F₂ population. The genetic map included one morphological (T₁) and 18 SSR loci, covering 96.2 cM with an average distance of 5.34 cM between two markers. Based on composite interval mapping (CIM), QTL(s) affecting lint percentage, fiber length, fiber length uniformity, fiber strength and spiny bollworm resistance (Earias spp.) were identified in the t₁ locus region on chromosome 6. The allele(s) originating from T586 of QTLs controlling lint percentage increased the trait phenotypic value while the alleles originating from Yumian 1 of QTLs affecting fiber length, fiber length uniformity, fiber strength and spiny bollworm resistance increased the trait phenotypic value.     

A high-density integrative linkage map for <Emphasis Type="Italic">Gossypium hirsutum</Emphasis>

Sequence-related amplified polymorphism (SRAP) combined with SSRs, RAPDs, and RGAPs was used to construct a high density genetic map for a F₂ population derived from the cross DH962 (G. hirsutum accession) × Jimian5 (G. hirsutum cultivar). A total of 4,096 SRAP primer combinations, 6310 SSRs, 600 RAPDs, and 10 RGAPs produced 331, 156, 17 and 2 polymorphic loci, respectively. Among the 506 loci obtained, 471 loci (309 SRAPs, 144 SSRs, 16 RAPDs and 2 RGAPs) were assigned to 51 linkage groups. Of these, 29 linkage groups were assigned to corresponding chromosomes by SSR markers with known chromosome locations. The map covered 3070.2 cM with a mean density of 6.5 cM per locus. The segregation distortion in this population was 9.49%, and these distorted loci tend to cluster at the end of linkage groups or in minor clusters on linkage groups. The majority of SRAPs in this map provided an effective tool for map construction in G. hirsutum despite of its low polymorphism. This high-density linkage map will be useful for further genetic studies in Upland cotton, including mapping of loci controlling quantitative traits, and comparative and integrative analysis with other interspecific and intraspecific linkage maps in cotton.     

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。     

转基因抗虫棉产量相关性状QTL的分子标记及定位

 采用亚洲棉渐渗的纤维强度突出的陆地棉优质新品系0-153与陆地棉转基因抗虫新品系sGK9708为亲本,构建了F₂及F_2∶3分离群体。利用3869对SSR引物筛选亲本,得到125对多态性引物。进一步对183个F₂群体单株分析得到150个多态性标记位点,其中100个标记位点连锁,构建20个连锁群,共覆盖660 cM,占棉花总基因组的14.67%,每个连锁群平均包含5个标记位点,标记间平均相距6.6 cM,其中13个连锁群确定了对应的染色体。利用F₂和F_2:3数据,通过复合区间作图,共检测到28个产量及相关因素的QTLs。这些控制产量性状的QTLs只存在于5个连锁群上,成簇分布。与皮棉产量性状有关的2个QTLs,均与其它多个产量相关性状的QTLs在同一个连锁区段内,增效基因遗传效应方向一致,有必要研究其在标记辅助选择中的效果。本研究没有检测到在多世代表现稳定的QTL。因此,需要培育重组自交系,进一步明确产量性状有关QTL的遗传效应。     

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.