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1.
Aluminium (Al) toxicity is a major constraint to crop productivity in acidic soils. A quantitative trait locus (QTL) analysis was performed to identify the genetic basis of Al tolerance in the wheat cultivar ‘Chinese Spring’. A nutrient solution culture approach was undertaken with the root tolerance index (RTI) and hematoxylin staining method as parameters to assess the Al tolerance. Using a set of D genome introgression lines, a major Al tolerance QTL was located on chromosome arm 4DL, explaining 31% of the phenotypic variance present in the population. A doubled haploid population was used to map a second major Al tolerance QTL to chromosome arm 3BL. This major QTL (Qalt CS .ipk-3B) in ‘Chinese Spring’ accounted for 49% of the phenotypic variation. Linkage of this latter QTL to SSR markers opens the possibility to apply marker-assisted selection (MAS) and pyramiding of this new QTL to improve the Al tolerance of wheat cultivars in breeding programmes.  相似文献   

2.
Association mapping was undertaken in common wheat to identify markers associated with pre-harvest sprouting tolerance (PHST). For this purpose, a population of 242 wheat genotypes and 250 SSR markers were used. The population used consisted of diverse germplasm, which carried sufficient phenotypic variation for PHS for conducting association mapping. The population was found to be structured and stratified into 15 sub-populations; the tolerant and moderately tolerant wheat genotypes were distributed in all the sub-populations. This feature of the population along with other information on population structure was used in association mapping using both the available models, the general linear model (GLM) and the mixed linear model (MLM); hopefully, this minimized the rate of false positives. As many as 30 markers were found to be associated with PHST, 26 markers with GLM and 17 markers with MLM; 13 markers were detected using both the approaches. Only eight SSR markers associated with QTL for PHST were such, which were located within the marker intervals that were earlier reported to carry QTLs for PHST. The remaining 22 markers that were found to be associated with PHST could not be associated with any of the genomic regions known to carry QTLs for PHST, which are known to occur on all the 42 chromosome arms of wheat genome.  相似文献   

3.
利用重组自交系群体检测水稻耐铝毒数量性状基因座   总被引：4，自引：0，他引：4  
利用Kinmaze / DV85 81个重组自交家系(RIL)作图群体,采用苗期单营养液水培鉴定方法,以相对根伸长量（RRE）作为耐铝毒性状的表型值,分析亲本和重组自交系群体对铝毒的耐性表现。利用Windows QTL Cartographer 1.13a软件共检测到5个耐铝毒QTLs,分别位于第1、5、8、9和11染色体上,各个QTL的贡献率在8.64%～18.60%之间,其  相似文献   

4.
小麦苗期性状能够指示品种的耐盐性。本研究以小麦骨干亲本燕大1817与品系北农6号衍生的230个重组自交系为材料,利用2013年3个不同时间的水培试验数据和已经构建的SSR和SNP高密度遗传连锁图谱分别对正常和盐胁迫条件下根数和最长根长等7个苗期性状进行QTL定位。利用完备复合区间作图法(ICIM)共检测到69个加性效应QTL(LOD≥2.5),分布于除1A染色体外的所有20条染色体上,单个QTL解释的表型变异率为2.70%~19.00%。有46个QTL的增效效应来自于燕大1817,有23个QTL的增效效应来自于北农6号。有12个QTL能够在3个或3个以上的环境中被检测到,在燕大1817中定位到稳定的多分蘖主效QTL QTn.cau-7BS.1和盐胁迫条件下特异表达的根数QTL QRn.cau-2A,解析了小麦骨干亲本燕大1817的繁茂性和抗逆性遗传基础,为解析小麦品种耐盐遗传机制和耐盐性的分子标记辅助选择提供了重要信息。  相似文献   

5.
Mapping QTLs for aluminum tolerance in maize   总被引：11，自引：0，他引：11  
Aluminum toxicity is one of the major constraints for plant development in acid soils, limiting food production in many countries. Cultivars genetically adapted to acid soils may offer an environmental compatible solution, providing a sustainable agriculture system. The aim of this work was to identify genomic regions associated with Al tolerance in maize, and to quantify the genetic effects on the phenotypic variation. A population of 168F3:4 families derived from a cross between two contrasting maize inbred lines for Al tolerance was evaluated using the NSRL and RSRL parameters in nutrient solution containing toxic level of aluminum. Variance analyses indicated that the NSRL was the most reliable phenotypicindex to measure Al tolerance in the population, being used for further QTL mapping analysis. RFLP and SSR markers were selected for bulked segregant analysis, and additional SSR markers, flanking the polymorphisms of interest, were chosen in order to saturate the putative target regions. Seven linkage groups were constructed using 17 RFLP and 34 SSR markers. Five QTLs were mapped on chromosomes 2, 6 and 8, explaining 60% of the phenotypic variation. QTL4 and marker umc043 were located on chromosomes 8and 5, close to genes encoding for enzymes involved in the organic acids synthesis pathways, a widely proposed mechanism for Al tolerance in plants. QTL2 was mapped in the same region as Alm2,also associated with Al tolerance in maize. In addition, dominant and additive effects were important in the control of this trait in maize. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

6.
Summary Quantitative trait loci (QTL) analysis for Al tolerance was performed in rice using a mapping population of 98 BC1F10 lines (backcross inbred lines: BILs), derived from a cross of Al-tolerant cultivar of rice (Oryza sativa L. cv. Nipponbare) and Al-sensitive cultivar (cv. Kasalath). Three characters related to Al tolerance, including root elongation under non-stress conditions (CRE), root elongation under Al stress (SRE) and the relative root elongation (RRE) under Al stress versus non-stress conditions, were evaluated for the BILs and the parents at seedling stage. A total of seven QTLs for the three traits were identified. Among them, three putative QTLs for CRE (qCRE-6, qCRE-8 and qCRE-9) were mapped on chromosomes 6, 8 and 9, respectively. One QTL for SRE (qSRE-4) was identified on chromosome 4. Three QTLs (qRRE-5, qRRE-9 and qRRE-10) for RRE were detected on chromosomes 5, 9, 10 and accounted for 9.7–11.8% of total phenotypic variation. Interestingly, the QTL qRRE-5 appears to be syntenic with the genomic region carrying a major Al tolerance gene on chromosome 6 of maize. Another QTL, qRRE-9, appears to be similar among different rice populations, while qRRE-10 is unique in the BIL population. The common QTLs for CRE and RRE indicate that candidate genes conferring Al tolerance in the rice chromosome 9 may be associated with root growth rates. The existence of QTLs for Al tolerance was confirmed in substitution lines for corresponding chromosomal segments. These results also provide the possibilities of enhancing Al tolerance in rice through using marker-assisted selection (MAS) and pyramiding QTLs.  相似文献   

7.
The ongoing rise in temperatures caused by global climate change is a critical climatic risk factor for rice production, and enhancing rice heat tolerance is an area of particular research interest. A recombinant inbred line (RIL) mapping population was developed from heat sensitive, rice cultivar IAPAR-9 crossed with heat tolerant, Liaoyan241. RIL and parental lines were exposed to high temperature at the heating and flowering stage in experiments in 2014 and 2015. As indicators of heat tolerance, the seed setting rate under natural (NS) and heat stress (HTS) conditions were measured, and the reduction rate of seed set (RRS) was calculated. Quantitative trait loci (QTL) analysis revealed eleven heat tolerance QTLs located on chromosomes 1, 3, 4, 5, and 6. Single QTL contribution rates were 4.75–13.81% and effect values were ? 5.98 to 5.00. Four major QTLs (qNS1, qNS4, qNS6, and qRRS1) were stable detected in different environments in both years. Thirteen QTLs with epistatic interactions and nine QTLs with environmental interactions were also detected. Major QTLs were all involved in epistatic and environmental interactions. Three QTLs from the SSR marker interval RM471 to RM177 region of chromosome 4 (qNS4, qHTS4, and qRRS4) were all involved in epistatic and environmental interactions and contributed to phenotypic variation, indicating that this region constituted a major QTL hotspot. The major QTL for heat tolerance identified in this study will aid in breeding tolerant cultivars and facilitating investigation of the molecular underpinnings of heat tolerance in rice.  相似文献   

8.
Salt-affected soils are generally classified into two main categories: saline and sodic (alkaline). Developing and using soybean (Glycine max (L.) Merr) cultivars with high salt tolerance is an effective way of maintaining sustainable production in areas where soybean growth is threatened by salt stress. Early classical genetics studies revealed that saline tolerance was conditioned by a single dominant gene. Recently, a series of studies consistently revealed a major quantitative trait locus (QTL) for saline tolerance located on linkage group N (chromosome 3) around the SSR markers Satt255 and Sat_091; other minor QTLs were also reported. In the case of sodic tolerance, most studies focused on iron deficiency caused by a high soil pH, and several QTLs associated with iron deficiency were identified. A wild soybean (Glycine soja Sieb. & Zucc.) accession with high sodic tolerance was recently identified, and a significant QTL for sodic tolerance was detected on linkage group D2 (chromosome 17). These studies demonstrated that saline and sodic tolerances were controlled by different genes in soybean. DNA markers closely associated with these QTLs can be used for marker-assisted selection to pyramid tolerance genes in soybean for both saline and sodic stresses.  相似文献   

9.
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   

10.
Cotton is a high-value per acre crop that is produced as a raw material for the textile industry. With the development of new technologies in the textile industry, much attention has been paid to fiber quality in conjunction with yield. The introgression cultivar “Acala Prema” is extensively planted in the Carolina/USA for its good fiber qualities, high yields and tolerance to Verticillium wilt. To conduct QTL mapping for fiber quality and yield in Acala-Prema, we developed a population of 180 recombinant inbred lines (RILs) from a single seed derived from a cross between this line and Chinese cultivar 86-1. We examined the yield performance of the RILs in five Chinese environments and fiber qualities in seven Chinese environments. A genetic linkage map comprising 279 loci was constructed using this RIL population, chiefly with SSR markers, and QTLs were repeatedly identified across diverse environments using the composite interval mapping method. A total of 86 nonredundant QTLs for yield and its components and fiber qualities were independently detected in five or seven environments; Prema alleles were responsible for the increase in trait values for 46 QTLs, while 86-1 was responsible for 40 QTLs. Notably, we detected the stable fiber strength QTL qFS-D3-1, which explained 4.51–17.55 % of PV, with LOD scores ranging from 2.83 to 7.09, and the fiber length qFL-D11-1, which explained 10.02–25.34 % of the PV. Eighteen environment epistatic QTLs were also detected. The QTLs detected in this study provide new information for improving fiber quality and may be especially valuable for marker-assisted selection.  相似文献   

11.
发掘人工合成小麦中千粒重QTL的有利等位基因   总被引：4，自引：1，他引：3  
廖祥政  王瑾  周荣华  任正隆  贾继增 《作物学报》2008,34(11):1877-1884
以人工合成小麦Am3为供体亲本,普通小麦莱州953为轮回亲本,经5次回交然后自交,培育出含85个株系的F2:3群体。以该群体为材料,用348对多态性SSR标记,进行全基因组扫描,发掘人工合成小麦中千粒重QTL的有利等位基因。利用复合区间作图法检测到3个千粒重QTL,其对表型变异的贡献率为10.9%~33.79%。其中,Am3的等位基因能够增加千粒重2.3~4.8 g。相关分析表明,该导入系群体的千粒重与穗粒数、穗数和株高无显著相关性。千粒重QTL与穗粒数、穗数性状的QTL不在同一位置,这有利于高千粒重基因与其他产量性状基因的聚合。采用混合线性模型作图法检测到1个千粒重QTL(QGw.caas-3D),该QTL与环境互作效应小,而且与复合区间作图法在3个环境中都检测到的QTL相同,表明QGw.caas-3D是一个稳定的主效QTL。  相似文献   

12.
W. Bourdoncle  H. W. Ohm 《Euphytica》2003,131(1):131-136
Fusarium head blight (FHB), primarily caused by Fusarium graminearum in North America, often results in significant losses in yield and grain quality of wheat (Triticum aestivum L.). Evaluation of FHB resistance is laborious and can be affected by environmental conditions. The development of DNA markers associated with FHB quantitative trait loci (QTL) and their use in breeding programs could greatly enhance selection. The objective of this study was to identify the location and effect of QTLs for FHB resistance using simple sequence repeat (SSR) markers. A population of wheat recombinant inbred lines derived from the cross ‘Huapei57-2’/‘Patterson’ was characterized for type II resistance in one field experiment and two tests under controlled conditions in the greenhouse. Bulked segregant analysis followed by QTL mapping was used to identify the major segregating QTLs. Results indicate that ‘Huapei 57-2’ may have the same resistance allele as ‘Sumai3’ at a QTL located on the short arm of chromosome 3B. Other QTLs of lower effect size were identified on the long arm of 3Band on chromosomes 3A and 5B. Our findings along with results from other studies demonstrate that the effect of the QTL on3BS is large and consistent across a wide range of genetic backgrounds and environments. Pyramiding this QTL with other FHB QTLs using marker-assisted selection should be effective in improving FHB resistance in a wheat breeding program. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

13.
Association mapping identifies quantitative trait loci (QTLs) by examining the marker-trait associations that can be attributed to the strength of linkage disequilibrium between markers and functional polymorphisms across a set of diverse germplasm. In this study, association mapping was performed to detect QTL-linked and genome wide SSR markers linked to phenolic compounds of extraction meal in a population of 49 genetically diverse oilseed rape cultivars of dark-seeded, winter-type oilseed rape accessions. Correction for population structure was performed using 559 genome wide SSR markers. Results showed that seed colour is an important contributor to seed meal quality. Totally, 52 SSR markers linked to phenolic compounds were detected, five of them being QTL linked markers. Some of these markers were already mapped on Brassica napus chromosomes that contain known QTL controlling oilseed rape meal quality traits. Our results demonstrate that association mapping is a useful approach to complement and enhance previous QTL information for marker-assisted selection.  相似文献   

14.
利用BC2F2高代回交群体定位水稻籽粒大小和形状QTL   总被引：1，自引：0，他引：1  
以我国优良籼稻恢复系蜀恢527为轮回亲本, 以来自菲律宾的Milagrosa为供体亲本, 培育了样本容量为199株的BC2F2高代回交群体。选取85个均匀分布在12条染色体上的多态性SSR标记进行基因型分析, 同时对粒长、粒宽、长宽比和千粒重4种性状进行了表型鉴定。采用性状－标记间的单向和双向方差分析对上述性状进行了QTL定位。单向方差分析(P<0.01)共检测到了10个控制粒长、粒宽、长宽比和千粒重的QTL, 其中有3个具有多效性。由于粒长和长宽比的高度相关性, 控制长宽比的2个QTL均能在粒长QTL中检测到。位于第3染色体着丝粒区域的qgl3b是一个控制粒长、长宽比和千粒重的主效QTL, 它可以分别解释粒长、长宽比和千粒重表型变异的29.37%、26.15%和17.15%。该QTL对于粒长、长宽比和千粒重均表现较大的加性效应(来自蜀恢527的等位基因为增效)和负向超显性。位于第8染色体的qgw8位点是一个控制粒宽的主效QTL, 同时也是控制千粒重的微效QTL, 能解释粒宽表型变异的21.47%和千粒重表型变异的5.16%。该QTL对粒宽和千粒重均具有较大的加性效应(来自蜀恢527的等位基因为增效)和正向部分显性。双向方差分析(P<0.005)共检测到61对显著的上位性互作, 涉及54个QTL, 其中23个是能同时影响2~4个性状的多效位点, 且有8个位点与单向方差分析检测到的相同。控制长宽比的13对上位性互作位点中, 与控制粒长的上位性互作位点完全相同的有8对。以上结果为进一步开展水稻籽粒大小和形状有利基因的精细定位、克隆和分子设计育种奠定了基础。  相似文献   

15.
以红丰11为轮回亲本、Clark为供体亲本构建回交群体进行耐旱性鉴定,对获得选择群体进行全基因组SSR标记扫描,计算供体基因型导入频率,利用卡方测验检测偏分离SSR位点,并结合GGT软件对各连锁群分析, 对5个耐旱相关性状进行QTL定位。以卡方测验检测到23个SSR偏分离位点(超导入),分布于10条连锁群。方差分析表明,8个叶片持水能力QTL分布于A1、B1、C2、E、L和N连锁群;9个根长QTL分布于C2、F、G和I连锁群;11个根干重QTL分布于A2、B1、B2、E、F、K、L、M和O连锁群;12个产量QTL分布于B1、D1a、E、F、G、I、L、M和O连锁群;7个生物量QTL分布于E、F、G、K、L和N连锁群。在E连锁群的Sat_136位点,对于叶片持水能力、根干重、产量和生物量具有一致性;在F连锁群的GMRUBP位点,对于根干重和生物量具有一致性,Satt586位点,对于根长、根干重和产量具有一致性;在K连锁群的Satt167位点,对于根干重和生物量具有一致性,SOYPRP1位点,对于根长和生物量具有一致性;在L连锁群的Satt398位点,对于根长和产量具有一致性,Satt694位点对于叶片持水能力和生物量具有一致性;在M连锁群的GMSL514位点,对于根干重和产量具有一致性;以上位点均与卡方测验检测到的“超导入”位点具有一致性。经过供体等位基因卡方测验和耐旱QTL定位,共检测到33个QTL,其中有17个同时被检测到。这些位点可能是控制大豆耐旱性的重要位点。  相似文献   

16.
周菊红  李轲  何蓓如  胡银岗 《作物学报》2010,36(12):2045-2054
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。  相似文献   

17.
Yellow mosaic disease (YMD) is one of the major diseases affecting mungbean (Vigna radiata (L.) Wilczek). In this study, we report the mapping of the quantitative trait locus (QTL) for mungbean yellow mosaic India virus (MYMIV) resistance in mungbean. An F8 recombinant inbred line (RIL) mapping population was generated in Thailand from a cross between NM10-12-1 (MYMIV resistance) and KPS2 (MYMIV susceptible). One hundred and twenty-two RILs and their parents were evaluated for MYMIV resistance in infested fields in India and Pakistan. A genetic linkage map was developed for the RIL population using simple sequence repeat (SSR) markers. Composite interval mapping identified five QTLs for MYMIV resistance: three QTLs for India (qYMIV1, qYMIV2 and qYMIV3) and two QTLs for Pakistan (qYMIV4 and qYMIV5). qYMIV1, qYMIV2, qYMIV3, qYMIV4 and qYMIV5 explained 9.33%, 10.61%, 12.55%, 21.93% and 6.24% of variation in disease responses, respectively. qYMIV1 and qYMIV4 appeared to be the same locus and were common to a major QTL for MYMIV resistance in India identified previously using a different resistant mungbean.  相似文献   

18.
H. Funatsuki    M. Ishimoto    H. Tsuji    K. Kawaguchi    M. Hajika    K. Fujino 《Plant Breeding》2006,125(2):195-197
Shattering of soybean pods prior to harvest leads to a reduction in yield. In order to identify simple sequence repeat (SSR) markers linked to quantitative trait loci (QTLs) conditioning pod shattering, QTL analysis was conducted using an recombinant inbred line (RIL) population segregating for this trait. The degrees of pod‐shattering resistance were evaluated by heat treatment applied to pods harvested from plants in the field and in a growth chamber. Composite interval mapping identified one major QTL between SSR markers Sat_093 and Sat_366 on linkage group J for both environments. The position and the effect of this QTL were confirmed in an F2 population derived from a cross between the pod shattering‐susceptible parental cultivar and a pod shattering‐resistant RIL. The SSR markers linked to the major QTL will be useful for marker‐assisted selection in soybean‐breeding programmes.  相似文献   

19.
越冬栽培稻是一类能越过自然冷冬季节并在第2年春季萌芽、正常开花结实、收获稻谷的水稻品种。本文通过对越冬栽培稻产量性状QTL分析,明确产量相关性状的遗传规律,旨在进一步解析越冬栽培稻产量性状的遗传机制,为育种创新利用提供理论依据。以3份越冬栽培稻构建的3个半同胞F2群体为材料。各考察15个产量相关性状,利用Excel 2003、GraphPad Prism 5.0和QTL IciMapping 4.10软件分析数据、绘制遗传图谱、定位QTL和联合分析。结果表明,产量性状表型值在3群体中呈连续正态分布,表现为数量性状遗传。共检测到37个QTL和26对上位性QTL,贡献率分别介于2.32%～36.31%和1.04%～2.05%;检测到9个同时影响2个及以上产量性状(一因多效)QTL标记区间;以联合分析检测到13个产量性状相关QTL,其中4个QTL区间与单群体检测QTL区间重叠;越冬栽培稻产量相关性状QTL以加–显性效应遗传为主、上位性遗传效应为辅。本研究将为越冬栽培稻产量相关基因挖掘及育种创新利用奠定基础。  相似文献   

20.
新疆棉花纤维品质性状的QTL分析   总被引：2，自引：1，他引：1  
 以自育高品质中长绒棉品种（新陆中9号提高系）9-1696为母本,与主栽品种中棉所35为父本配置单交组合,筛选出12对SSR引物在F2群体和B1群体进行纤维长度、整齐度、比强度和伸长率4个纤维品质性状的QTL分析,采用区间作图法（LOD>2.0）,在F2群体中检测到6个与纤维品质性状连锁的QTL位点。其中,检测到纤维长度、纤维整齐度、伸长率各1个QTL位点,比强度检测到3个QTL。在B1群体中检测到2个QTL,分别与比强度和纤维长度连锁。  相似文献   

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