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1.
Epicotyl length (ECL) of adzuki bean (Vigna angularis) affects the efficiency of mechanized weeding and harvest. The present study investigated the genetic factors controlling ECL. An F2 population derived from a cross between the breeding line ‘Tokei1121’ (T1121, long epicotyls) and the cultivar ‘Erimo167’ (common epicotyls) was phenotyped for ECL and genotyped using simple sequence repeats (SSRs) and single-nucleotide polymorphism (SNP) markers. A molecular linkage map was generated and fifty-two segregating markers, including 27 SSRs and 25 SNPs, were located on seven linkage groups (LGs) at a LOD threshold value of 3.0. Four quantitative trait loci (QTLs) for ECL, with LOD scores of 4.0, 3.4, 4.8 and 6.4, were identified on LGs 2, 4, 7 and 10, respectively; together, these four QTLs accounted for 49.3% of the phenotypic variance. The segregation patterns observed in F5 residual heterozygous lines at qECL10 revealed that a single recessive gene derived from T1121 contributed to the longer ECL phenotype. Using five insertion and deletion markers, this gene was fine mapped to a ~255 kb region near the end of LG10. These findings will facilitate marker-assisted selection for breeding in the adzuki bean and contribute to an understanding of the mechanisms associated with epicotyl elongation.  相似文献   

2.
A cassava F1 population raised from the cross SC6 × Mianbao was used to construct a genetic linkage map. The map incorporated 200 polymorphic amplified fragment length polymorphism, sequence-related amplified polymorphism, simple sequence repeat (SSR), and expressed sequence tag (EST)–SSR markers which fit a 1:1 segregation ratio. It comprised 20 linkage groups (LGs) and spanned a genetic distance of 1645.1 cM with an average marker interval of 8.2 cM. Fifty-seven repeatedly detected QTLs (rd-QTLs) for three phenotypic traits (fresh root yield, root dry matter content, and root starch content) were identified in the F1 population in four trials of year 2003, 2004, 2005, and 2008 by inclusive composite interval mapping. Among the 57 rd-QTLs, 25 rd-QTLs were linked to SSR/EST–SSR markers, which will help to facilitate marker-assisted selective breeding in cassava, and 15 marker intervals on ten LGs showed pleiotropic effects.  相似文献   

3.
甘蔗SSR和AFLP分子遗传连锁图谱构建   总被引：3，自引：0，他引：3  
刘新龙  毛钧  陆鑫  马丽  蔡青  范源洪 《作物学报》2010,36(1):177-183
采用甘蔗商业品种Co419与野生种割手密Y75/1/2杂交,获得269个单株,组成F1群体,用F102/356与商业品种ROC25回交获得266个单株,组成BC1群体。利用筛选的多态性条带丰富的36对SSR引物和12对AFLP引物,对两个群体进行PCR扩增和分子遗传连锁分析,构建甘蔗分子遗传连锁图谱。用F1群体获得630个分离标记,经χ2检测,298个标记为单双剂量标记,占总标记数的47%;用BC1群体获得571个分离标记,有264个标记为单双剂量标记,占总标记数的46%;4个亲本获得单双剂量标记的数量依次为Co41902/356Y75/1/2ROC25。在LOD≥5.0,相邻标记遗传距离≤40cM的条件下,F1群体有134个单双剂量标记被纳入55个连锁群,其中39个连锁群归属8个同源组,16个未列入,总遗传距离为1458.3cM,标记间平均图距为10.9cM;BC1群体有133个单双剂量标记被纳入47个连锁群,其中34个连锁群归属于8个同源组,13个连锁群未列入,总遗传距离为1059.6cM,标记间平均图距为8.0cM。从4个亲本单双剂量标记进入的连锁群数来看,Co419最多,归入34个连锁群,其次为Y75/1/2,归入20个连锁群,第3为02/356和ROC25,归入19个连锁群。研究结果表明,从单双剂量标记比例、形成连锁群数量、总遗传距离来看,F1群体构图质量要优于BC1群体。  相似文献   

4.
Genetic improvement of sugar content in sugarcane would benefit from the availability of sufficient DNA markers and a genetic map. Genetic linkage maps were constructed to identify quantitative trait loci (QTLs) for seedling brix (SB), brix (B), sucrose percent in juice (SUC), stalk number (SN), stalk length (SL), stalk diameter (SD), internodes (INT), number of green leaves (NGL), at three crop cycles across seven environments in a segregating population with 207 individuals derived from a bi-parental cross of sugarcane elite cultivars. Linkage analysis led to the construction of eight linkage groups (LGs) for Co86011 and sixteen LGs for CoH70. The combined length of the two linkage maps was 2606.77 cM distributed over 24 LGs. 31 QTLs were identified: 2 for SB, 7 for B, 6 for SUC, 4 for SN, 1 for SL, 3 for SD, 6 for INT and 2 for NGL at LOD scores ranging from 2.69 to 4.75. 7 QTLs (22 %) had stable effect across crop year and locations. Markers from parents were found to be associated with both positive and negative effect on all of the traits analyzed. The most important QTLs intervals identified in this study using single-dose marker, were qB2, qSUC2, qINT2 and qB2, qSUC2, qSL2, qINT2 located between SSR markers UGSM31548 and UGSM31649. These QTLs could be put into use in marker assisted breeding.  相似文献   

5.
Summary Molecular mapping is a promising strategy for studying and understanding traits with complex genetic control, such as partial resistance to oat crown rust. The objectives of this research were to develop molecular maps from the progenies of the cross UFRGS7 (susceptible) × UFRGS910906 (partially resistant) and to identify QTLs (quantitative trait loci) associated to partial resistance to oat crown rust in two generations of that population.DNA of 86 genotypes of the F2 and 90 genotypes of the F6 UFRGS7 × UFRGS910906 population were used to generate AFLP markers. Molecular maps were constructed using Mapmaker Exp. 3.0 and QTLs for partial resistance to oat crown rust were identified with Mapmaker/QTL software. Five hundred and fifty seven markers in the F2 and 243 markers in the F6 generations were identified. The F2 map integrated 250 markers in 37 linkage groups. The F6 map integrated 86 markers in 17 linkage groups.Five QTLs were identified for partial resistance to oat crown rust in the F2 generation and three QTLs in the F6. The QTL identified on F6 through the PaaaMctt340 AFLP marker showed consistency across two environments and two generations (F4 and F6), and appear to have potential for marker-assisted selection in oat.  相似文献   

6.
Low-temperature soluble carbohydrate accumulations are commonly associated with anthocyanin coloration, attenuated growth, and cold adaptation of cool-season grasses. A total of 647 AFLP markers were tested for associations with anthocyanin coloration, tiller formation, leaf formation, cumulative leaf length, percent soluble carbohydrate, and dry matter regrowth among replicated clones of an admixed Leymus wildrye breeding population evaluated in low-temperature growth chambers. The admixed breeding population was derived from a heterogeneous population of L. cinereus × L. triticoides F1 hybrids, with two additional generations of open pollination. Two AFLP linkage maps, constructed from two full-sib mapping populations derived from the same F1 hybrid population, were integrated to produce a framework consensus map used to examine the distribution of marker-trait associations in the admixed F1OP2 population. Thirty-seven linkage blocks, spanning 258 cM (13.6%) of the 1895 cM consensus map, contained 119 (50%) of the 237 markers showing at least one possible trait association (P < 0.05). Moreover, 28 (68%) of the 41 most significant marker-trait associations (P < 0.005) were located in 15 QTL linkage blocks spanning 112.9 cM (6%) of the linkage map. The coincidence of these 28 significant marker-trait associations, and many less significant associations, in 15 relatively small linkage blocks (0.6 cM to 21.3 cM) provides evidence of admixture linkage disequilibrium QTLs (ALD QTLs) in this heterogeneous breeding population. At least four of the remaining 13 putative marker-trait associations (P < 0.005) were located in genetic map regions lacking other informative markers. The complexity of marker-trait associations results from heterogeneity within and substantial divergence among the parental accessions.  相似文献   

7.
To develop a high density linkage map in faba bean, a total of 1,363 FBES (Faba bean expressed sequence tag [EST]-derived simple sequence repeat [SSR]) markers were designed based on 5,090 non-redundant ESTs developed in this study. A total of 109 plants of a ‘Nubaria 2’ × ‘Misr 3’ F2 mapping population were used for map construction. Because the parents were not pure homozygous lines, the 109 F2 plants were divided into three subpopulations according to the original F1 plants. Linkage groups (LGs) generated in each subpopulation were integrated by commonly mapped markers. The integrated ‘Nubaria 2’ × ‘Misr 3’ map consisted of six LGs, representing a total length of 684.7 cM, with 552 loci. Of the mapped loci, 47% were generated from multi-loci diagnostic (MLD) markers. Alignment of homologous sequence pairs along each linkage group revealed obvious syntenic relationships between LGs in faba bean and the genomes of two model legumes, Lotus japonicus and Medicago truncatula. In a polymorphic analysis with ten Egyptian faba bean varieties, 78.9% (384/487) of the FBES markers showed polymorphisms. Along with the EST-SSR markers, the dense map developed in this study is expected to accelerate marker assisted breeding in faba bean.  相似文献   

8.
遗传图谱的构建及整合是开展花生分子育种研究的基础,利用多个作图群体整合遗传图谱是解决图谱标记密度低的有效途径。本研究采用基于锚定SSR标记的作图策略,构建3个F_2群体3张遗传连锁图,利用Join Map 3.0软件整合图谱,获得一张包含20个连锁群、792个位点、总遗传距离为2079.50 c M,标记间平均距离为2.63 c M的整合图谱,各连锁群标记数在20~66个之间,遗传距离在59.10~175.80 c M之间。将3个分离群体中检测到的与荚果及种子大小相关的QTL区段与整合连锁图的标记比较发现,各群体中检测到的位于各染色体上的QTL在整合图谱中都能出现,有些QTL标记区间在整合图谱中存在更多的标记,为今后利用这些标记进行精细定位奠定了基础。  相似文献   

9.
Amplified fragment length polymorphism (AFLP) and microsatellite (SSR) markers were applied to a segregation population of 111 genotypes derived from a pseudo-testcross of hop (Humulus lupulus L.) in order to detect quantitative trait loci (QTLs) for alpha-acid content and yield traits. A total of 199 markers (150 AFLPs, 43 SSRs, one hypothetical sex marker, five chs genes) were located on the 20 linkage groups (LGs) of the maternal and paternal maps, covering 706 and 616 cM, respectively. Due to the presence of 16 common biparental SSR markers, homology of seven LGs between parental maps could be inferred. The progeny segregated quantitatively for alpha-acid content and yield determined in the years from 2002–2006. A total of 13 putative QTLs for alpha acid content, 13 for dry cone weight and 18 for harvest index were identified on the two maps across years. Possible homologies between the detected QTLs on the two maps as well as in different years were established for all three traits. The most promising QTL for alpha acid content was identified on LG03 flanked by two AFLP markers (E-ACC-M-CAA103F*/P-ACA-M-CAC412F). From 13.80 to 36.64% higher content of alpha acids than the averages obtained in different years was observed in plants having both flanking markers. The candidate region for further characterization of QTLs for yield traits was located on LG01 where the putative QTLs for harvest index were detected on both maps in each of the 5 years. The QTLs identified represent an important improvement in alpha acids MAS and the first step towards marker-assisted breeding for hop yield.  相似文献   

10.
陆地棉高品质品系纤维品质性状QTL的分子标记及定位   总被引：4，自引：1，他引：3  
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。  相似文献   

11.
Ascochyta blight is a devastating disease of chickpea. Breeders have been trying to introduce resistance from wild Cicer into cultivated chickpea, however, the effort is hampered by the frequent genetic drag of undesirable traits. Therefore, this study was aimed to identify potential markers linked to plant growth habit, ascochyta blight resistance and days to flowering for marker-assisted breeding. An interspecific F2 population between chickpea and C. reticulatum was constructed to develop a genetic linkage map. F2 plants were cloned through stem cuttings for replicated assessment of ascochyta blight resistance. A closely linked marker (TA34) on linkage group (LG) 3 was identified for plant growth habit explaining 95.2% of the variation. Three quantitative trait loci (QTLs) explaining approximately 49% of the phenotypic variation were found for ascochyta blight resistance on LG 3 and LG 4. Flowering time was controlled by two QTLs on LG3 explaining 90.2% of the variation. Ascochyta blight resistance was negatively correlated with flowering time (r = −0.22, P < 0.001) but not correlated with plant growth habit.  相似文献   

12.
A genetic linkage map of walnut containing 2,220 single nucleotide polymorphisms (SNPs) in 16 linkage groups (LGs) was constructed using an F1 mapping population from a cross between “Chandler” and “Idaho,” two contrasting heterozygous parents. Five quantitative yield traits, lateral fruitfulness, harvest date and three nut traits (shell thickness, nut weight and kernel fill) were then mapped on to linkage groups. A significant quantitative trait locus (QTL) in LG 11 with negative additive effects suggested heterozygote superiority in the expression of lateral bearing. A set of three QTLs explaining ~10% of the variation in harvest date was located in LG 1. Shell thickness, nut weight and kernel fill were under the control of two to three linked pleiotropic QTLs in LG 1 segregating from “Idaho.” The marginal positive additive effects of QTLs for harvest date, shell thickness and nut weight and small negative additive effects for kernel fill suggested that the QTLs had a marginal effect on the expression of these traits.  相似文献   

13.
以甘蓝型黄籽油菜GH06和甘蓝型黑籽油菜P174为亲本,通过单粒法连续自交8代构建重组自交系群体,应用SSR标记绘制31个连锁群(LGs)的遗传连锁图谱,图谱总长1437.1 cM,相邻标记间的平均距离为3.89 cM。对4个不同环境下RIL8群体中每个株系籽粒含油量、蛋白质、纤维素和半纤维素含量进行了近红外分析,性状相关性表明含油量与其他3个性状均表现负相关,蛋白质含量与纤维素和半纤维素分别表现负相关和正相关。结合构建的遗传图谱采用复合区间作图法分析4个性状QTL,共检测到26个QTL,分布在N2、N3、N8、N9、N11、N13、N16和N17连锁群上,其中8个含油量QTL可解释表型变异的4.96%~21.83%;6个蛋白含量QTL,可解释表型变异的3.12%~14.28%;4个纤维素含量QTL,可解释表型变异的4.60%~17.29%;8个半纤维素含量QTL,可解释表型变异率的6.66%~16.68%。在N8上,发现有含油量QTL与半纤维素含量QTL重叠的区段。在N9上,发现有纤维素含量QTL与半纤维素含量QTL重叠的区段,上述2个区段重叠QTL加性效应方向相反。本研究认为油菜种子含油量、蛋白质、纤维素和半纤维素属于典型的数量性状,受环境影响较大,与这些QTL紧密相关的分子标记可为下一步分子标记辅助育种提供一定技术支撑。  相似文献   

14.
Floral scent is a very important trait in plant evolution. Currently, little is known about the inheritance of floral scent in cowpea (Vigna unguiculata L.) or changes that might have occurred during its domestication. Therefore, we analysed scent volatiles and molecular markers in a population of 159 F7 recombinant inbred lines derived from a cross of a domesticated blackeye cowpea cultivar, ‘524B’ and a wild accession ‘219‐01’. Using gas chromatography‐mass spectrometry (GC–MS) 23 volatile compounds were identified that fall into five general functional categories. Twenty‐two of the compounds displayed quantitative variation in the progeny, and a total of 63 QTLs influencing the amounts of these volatiles were mapped onto the cowpea genetic marker map. Although QTLs for volatile compounds putatively involved in cowpea flower scent were found on 9 of the 11 cowpea chromosomes, they were not evenly distributed with QTLs mainly clustered on LGs 1, LGs 2 and LG 4. Our results serve as a starting point for both more detailed analyses of complex scent biosynthetic pathways and the development of markers for marker‐assisted breeding of scented rose varieties.  相似文献   

15.
Powdery mildew disease in mungbean is caused by the fungus, Erysiphe polygoni D.C. We identified two quantitative trait loci (QTLs) controlling resistance to the disease in a RIL population of 190 F7 lines. The population was developed from the cross between a susceptible cultivar, “Kamphaeng Saen 1” and a resistant line, “VC6468-11-1A”. Reaction to the disease was evaluated for resistance in field and greenhouse conditions. Results from analysis of variance revealed that 15 SSR loci on three linkage groups (LG) associated with the resistance. Composite interval mapping consistently identified two QTLs on two LGs, qPMR-1 and qPMR-2, conferring the resistance. qPMR-1 and qPMR-2 accounted for 20.10 and 57.81% of the total variation for plant response to the disease, respectively. Comparison based on common markers used in our and previous studies suggested that qPMR-2 is possibly the same as the major QTL reported earlier using another resistant source. The SSR markers flanking and closely linked to qPMR-1 (CEDG282 and CEDG191) and qPMR-2 (MB-SSR238 and CEDG166) are useful for marker-assisted selection for mungbean resistance to powdery mildew.  相似文献   

16.
栽培种花生是异源四倍体,基因组大,构建花生的分子遗传连锁图谱并对相关性状进行QTL定位研究的工作缓慢。本研究以遗传差异大的亲本组配杂交组合富川大花生×ICG6375构建F2作图群体,采用公开发表的2653对SSR引物,构建了一张含有234个SSR标记、分布于20个连锁群的栽培种花生遗传图谱。该图谱覆盖基因组的长度为1683.43c M,各个连锁群长度在36.11~131.48 c M之间,每个连锁群的标记数在6~15个之间,标记间的平均距离为7.19 c M。结合F3在湖北武汉和阳逻环境下的主茎高和总分枝数鉴定结果,应用Win QTLCart 2.5软件采用复合区间作图法进行了QTL定位和遗传效应分析。共检测到17个与主茎高和总分枝数相关的QTL位点,贡献率在0.10%~10.22%之间,分布于8个连锁群上。综合分析武汉和阳逻环境的鉴定结果,获得重复一致的与主茎高相关的6个QTL,其中q MHA061.1和q MHA062.1位于连锁群LG06上TC1A2~AHGS0153标记区间,贡献率为5.49%~8.95%;q MHA061.2和q MHA062.2位于LG06上AHGS1375~PM377标记区间,贡献率为2.93%~5.83%;q MHA092.2和q MHA091.1位于连锁群LG09上GM2839~EM87标记区间,贡献率为0.53%~9.43%。  相似文献   

17.
Capsaicinoids are pungent compounds used for industrial and medical purposes including food, medicine and cosmetics. The Indian local variety ‘Bhut Jolokia’ (Capsicum chinense Jacq.) is one of the world's hottest chilli peppers. It produces more than one million Scoville heat units (SHUs) in total capsaicinoids. In this study, our goal was to identify quantitative trait loci (QTLs) responsible for the high content of capsaicin and dihydrocapsaicin in ‘Bhut Jolokia’. Capsicum annuum ‘NB1’, a Korean pepper inbred line containing 14 000 SHUs, was used as a maternal line. An F2 population derived by crossing between ‘NB1’ and ‘Bhut Jolokia’ was generated to map QTLs for capsaicinoids content. A total of 234 markers, including 201 HRM, 21 SSR, 2 CAPS and 10 gene‐based markers of the capsaicinoid synthesis pathway, were mapped. The final map covered a total distance of 1175.2 cM and contained 12 linkage groups corresponding to the basic chromosome number of chilli pepper. Capsaicin and dihydrocapsaicin content were analysed in 175 F2 pepper fruits using the HPLC method. The maximum total capsaicinoids content was 1389 mg per 100g DW (dry weight), and the minimum content was 11 mg per 100g DW. Two QTLs (qcap3.1 and qcap6.1) for capsaicin content were identified on LG3 and LG6, and two QTLs (qhdc2.1 and qdhc2.2) for dihydrocapsaicin content were located on LG2. We did not detect QTLs for total capsaicinoids content. The QTL positions for capsaicin content were different from those for dihydrocapsaicin content. These results indicate that the complexity of selecting for more pungent chilli peppers must be considered in a chilli pepper breeding programme. The QTL‐linked markers identified here will be helpful to develop more pungent pepper varieties from ‘Bhut Jolokia’, a very hot pepper.  相似文献   

18.
Plant architecture is important for cotton cultivation and breeding. In this study, two mapping generations/populations F2 and F2:3 in Upland cotton (Gossypium hirsutum L.), derived from ‘Baimian1’ and TM‐1, were used to identify quantitative trait loci (QTLs) for 10 plant architecture traits. A total of 55 main‐effect QTLs (M‐QTLs) were detected. Four common M‐QTLs, qTFB‐10(F2/F2:3) for total fruit branches, qFBL‐26b(F2)/qFBL‐26(F2:3) for fruit branch length, qFBA‐5(F2/F2:3) for fruit branch angle and qFBN‐26b(F2)/qFBN‐26(F2:3) for fruit branch nodes, were found. The synergistic alleles and the negative alleles can be utilized in cotton plant architecture breeding programmes according to specific breeding objectives. Altogether 54 pairs of epistatic QTLs (E‐QTLs) exhibiting the interactions of additive‐by‐additive (AA), additive‐by‐dominant (AD), dominant‐by‐additive (DA) and dominant‐by‐dominant (DD) were detected. The epistasis appeared to be an important contributor to genetic variation in cotton plant architecture traits. Therefore, the identified markers associated with E‐QTLs as well as M‐QTLs will be of importance in future breeding programmes to develop cotton cultivars exhibiting desirable plant architecture.  相似文献   

19.
Exploiting genes and quantitative trait loci (QTLs) related to maize (Zea mays L.) alkaline tolerance is helpful for improving alkaline resistance. To explore the inheritance of maize alkaline tolerance at the seedling stage, a mapping population comprising 151 F2:3 lines derived from the maize cross between Zheng58, tolerant to alkaline, and Chang7-2, sensitive to alkaline, was used to establish a genetic linkage map with 200 SSR loci across the 10 maize linkage groups, with an average interval of 6.5 cM between adjacent markers. QTLs for alkaline resistant traits of alkaline tolerance rating (ATR), germination rate (GR), relative conductivity (RC), weight per plant (WPP) and proline content (PC) were detected. The obtained results were as follows: Five QTLs on chromosomes 2, 5 and 6 (GR and WPP: chr. 2; PC and ATR: chr. 5; and RC: chr. 6) were mapped. For precise mapping of the QTLs related to alkaline resistance, two bulked deoxyribonucleic acid (DNA) pools were constructed using individual DNAs from the most tolerant 30 F2 individuals and the most sensitive 30 F2 individuals according to the ATR and used to establish a high density map of SLAF markers strongly associated with the ATR by specific locus amplified fragment sequencing (SLAF-Seq) combined with super bulked segregant analysis (superBSA). One marker-intensive region involved three SLAFs at 296,000–6,203,000 bp on chromosome 5 that were closely related to the ATR. Combined with preliminary QTL mapping with superBSA, two major QTLs on chromosome 5 associated with alkaline tolerance at the maize seedling stage were mapped to marker intervals of dCap-SLAF31521 and dCap-SLAF31535 and phi024 and dCap-SLAF31521, respectively. These QTL regions involved 9 and 75 annotated genes, respectively. These results will be helpful for improving maize alkaline tolerance at the seedling stage by marker-assisted selection programs and will be useful for fine mapping QTLs for maize breeding.  相似文献   

20.
Due to its critical importance in crop yield, the photoperiodic regulation of flowering time is considered an important trait in sorghum breeding programs. In this study, quantitative trait loci for flowering time were detected using an F2 population derived from a cross between Kikuchi Zairai, a late-flowering cultivar originating from Japan and SC112, an early-flowering cultivar originating from Ethiopia. F2 plants were grown with their parents under a natural day length and a 12 h day length. Two linkage maps were constructed using 213 simple sequence repeats markers. Nine quantitative trait loci controlling flowering time were identified in F2 plants grown under a natural day length, whereas 7 QTLs were identified under a 12 h day length. Five QTLs controlling flowering time were shared under both of the day length conditions.  相似文献   

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