基于单片段代换系的水稻抽穗期QTL定位及上位性分析

抽穗期是水稻重要的农艺性状,它决定水稻品种的地域适应性和季节适应性,是重要的育种目标之一。本研究从两个水稻单片段代换系杂交分离群体中筛选到8个次级单片段代换系和2个双片段聚合系,经重叠群作图分析,鉴定出2个与抽穗期有关的QTL。qHD3位于第3染色体短臂,qHD6位于第6染色体的短臂中部。在长日照条件下,Lemont的qHD3等位基因可促进水稻早抽穗,Tetep的qHD6等位基因则延迟水稻抽穗。另外,上位性分析表明,在长日照条件下,qHD3和qHD6之间存在着显著的上位性互作效应。     

利用单片段代换系定位水稻抽穗期QTL

 抽穗期是水稻品种的重要农艺性状之一，对抽穗期QTL进行定位并研究其遗传效应在水稻育种中是至关重要的。本研究利用以6个水稻品种为供体的52个单片段代换系为试验材料，通过t测验比较单片段代换系与受体亲本华粳籼74之间抽穗期的差异，对代换片段上的抽穗期QTL进行了鉴定。以P≤0.001为阈值共鉴定出20个抽穗期QTL，这些QTL分布于水稻的10条染色体。QTL加性效应值为-5.9～1.1，加性效应百分率为-7.4%～1.4%。有8个QTL被定位在小于10.0 cM的区段内。利用1个单片段代换系与华粳籼74杂交发展的F2群体对qHD-3-1进行了定位。在作图群体中，早抽穗和迟抽穗植株数符合3:1的分离比，早抽穗表现为显性。利用微卫星标记将qHD-3-1定位于3号染色体短臂，PSM304和RM569分别位于其两侧，遗传距离分别为2.4 cM和5.1 cM。     

Dissection of QTLs for Yield Traits on the Short Arm of Rice Chromosome 6

This study was undertaken to dissect quantitative trait loci （QTLs） controlling yield traits on the short arm of rice chromosome 6. A residual heterozygous line that carries a heterozygous segment extending from RM587 to RM19784 on the short arm of rice chromosome 6 was selected from an F7 population of the indica rice cross Zhenshan 97B/Milyang 46. An F2：3 population consisting of 221 lines was derived and grown in two trial sites. Six yield traits including number of panicles per plant, number of filled grains per panicle, total number of spikelets per panicle, spikelet fertility, 1 000-grain weight, and grain yield per plant were measured. An SSR marker linkage map was constructed and employed to determine QTLs for yield traits with Windows QTL Cartographer 2.5. QTLs were detected in the target interval for all the traits analyzed except NP, with phenotypic variance explained by a single QTL ranging between 6.3% and 35.2%. Most of the QTLs for yield components acted as additive QTLs, while the three QTLs for grain yield had dominance degrees of 1.65, 0.84, and -0.42, respectively. It was indicated that three or more QTLs for yield traits were located in the target region. The genetic action mode, the direction of the QTL effect, and the magnitude of the QTL effect varied among different QTLs for a given trait, and among QTLs for different traits that were located in the same interval.     

籼稻不同定位群体的抽穗期和株高QTL比较研究

 【目的】通过分析控制不同定位群体水稻抽穗期、株高和产量性状表现的QTL,挖掘同时控制株高与产量性状且对抽穗期影响小的QTL区间,为水稻高产育种提供参考。【方法】以杂交稻恢复系密阳46作为共同父本,分别与保持系协青早B和珍汕97B配组,构建2个籼籼交重组自交系群体,在同一地点多年种植,对不同群体抽穗期和株高相关的QTL定位结果进行比较。【结果】共定位到12个抽穗期QTL和11个株高QTL,其中2个抽穗期QTL在2个群体中都能检测到,分别位于第6染色体短臂和第7染色体长臂近着丝粒区域。通过与前期相同群体产量性状QTL定位结果比较,发现6个多效性区间,其中,1个同时控制抽穗期、株高和产量性状,3个同时控制抽穗期和产量性状,2个同时控制株高和产量性状。【结论】相对于共同的父本密阳46,水稻矮败型保持系协青早B与野败型保持系珍汕97B对抽穗期和株高的遗传控制存在较大差异,并以株高更为明显。第2染色体长臂RM6—RM240的QTL作用较稳定,对株高和产量性状作用方向一致,且对抽穗期无显著影响,对于通过“矮中求高”实现水稻高产育种具有重要的应用价值。     

水稻第6染色体短臂产量性状QTL簇的分解

【目的】将水稻第6染色体短臂上产量性状QTL分解到更小的区间中。【方法】从珍汕97B/密阳46重组自交系群体筛选到针对第6染色体短臂RM587-RM19784区间的剩余杂合体,衍生了一个由221个株系组成的F2:3群体,种植于海南和浙江两地,考察每株穗数、每穗实粒数、每穗总粒数、千粒重、结实率和单株产量,建立SSR标记连锁图,应用Windows QTL Cartographer 2.5检测QTL。【结果】在所分析的6个性状中,除穗数外在第6染色体短臂上的目标区间均检测到QTL,分别座落于目标区域中3个以上的不同区间中,单个QTL对群体性状表型变异的贡献率为6.3%～35.2%;控制产量构成因子的QTL基本以加性作用为主,但3个单株产量QTL的显性度分别为1.65、0.84和0.42。【结论】目标区间存在3个以上的产量性状QTL,且同一区间控制不同性状的QTL、不同区间控制同一个性状的QTL在遗传作用模式、效应方向和效应大小上存在一定差异。     

Quantitative Trait Loci for Panicle Size and Grain Yield Detected in Interval RM111-RM19 784 on the Short Arm of Rice Chromosome 6

A rice residual heterozygous line （RHL） carrying a heterozygous segment extending from RM111 to RM19784 on the short arm of rice chromosome 6 was selected from a RHL-derived population used previously. The resultant F2：3 population was used to detect quantitative trait loci （QTLs） for three yield traits, the number of spikelets per panicle （NSP）, the number of grains per panicle （NGP） and grain yield per plant （GY）. Two QTLs for NSP, one QTL for NGP and one QTL for GY were detected, all of which were partially dominant and had the enhancing alleles from the maternal line Zhenshan 97B. Analysis based on the genotypic groups of the markers closely linked to the two QTLs for NSP indicated that they did not interact with each other. Two F2 populations and two near isogenic line （NIL） sets segregating in two sub-regions of interval RM111-RM19784 were developed. The two QTLs for NSP were validated, of which one had major effect and was co-segregated with heading date gene Hdl, and the other had smaller effect and was located in an upper region linked to Hdl. The two regions also showed significant effects on the number of filled grain and grain yield, although the effect on the number of filled grain was less consistent.     

水稻单片段代换系抽穗期QTL鉴定及遗传分析

适宜的抽穗期是水稻（Oryza sativa）获得理想产量的前提。本研究利用带有晚抽穗基因的单片段代换系（SSSL）为供体,华粳籼74为受体亲本,发展F2次级分离群体。通过t测验比较单片段代换系与受体亲本华粳籼74之间抽穗期的差异,同时对代换片段上的抽穗期QTL进行鉴定。以P≤10-6为阈值鉴定出抽穗期QTL,此QTL位于水稻的第6染色体。调查记录F2次级分离群体单株抽穗期,并对统计结果进行卡方（χ2）测验。结果显示,F1代单株表现为早抽穗,F2代早抽穗和迟抽穗植株数符合3∶1的分离比,早抽穗表现为显性。     

水稻抽穗期QTL的聚合及其互作分析

本研究以10个单片段代换系为材料,进行抽穗期QTL鉴定,得到4个存在抽穗期QTL的单片段代换系:W11-15-7-39-2、W02-15-7-3、W08-16-3-2、W22-9-5-2-4-9-3,其上的QTL分别命名为qHD2-1、qHD8-1、qHD3-1、qHD10-1;基因聚合、互作分析结果表明qHD2-1对qHD8-1、qHD8-1对qHD3-1、qHD3-1对qHD10-1分别表现上位性。     

利用单片段代换系定位水稻粒形QTL

 【目的】水稻谷粒形状（粒长、粒宽和长宽比）是衡量稻米外观品质的重要指标之一，为更好地开展粒形分子育种，对水稻粒形QTL进行分子定位。【方法】以单片段代换系（SSSL）为材料构建分离群体，利用微卫星标记对控制水稻谷粒长和谷粒宽的2个粒形QTL进行分子定位。【结果】粒宽QTL Gw-8被定位于第8染色体长臂末端微卫星标记RM502与RM447之间, 遗传距离均为0.3 cM。在此基础上构建了覆盖Gw-8的物理图谱，RM502与RM447位于同一克隆AP005529，两者之间的物理距离为55.0 kb。粒长QTL gl-3被定位于第3染色体着丝粒附近的微卫星标记RM6146和PSM377之间，遗传距离分别为1.5 cM和11.0 cM。【结论】利用单片段代换系能准确地定位水稻粒形QTL，这两个粒形QTL的定位为其克隆及稻米外观品质的分子育种奠定了基础。     

普通野生稻转育后代稻褐飞虱抗性基因的初步定位

通过BR96与白56构建F2群体,利用均匀分布于水稻全基因组的122对多态性引物标记分析F2群体的基因型,构建遗传连锁图谱,考查F2衍生的F3各家系的褐飞虱苗期抗性等级,检测水稻褐飞虱抗性数量性状位点(QTL)。结果显示:分别在第3、4和6号染色体上各扫描到一个抗褐飞虱QTL位点,QBph3位于第3染色体RM489-RM282之间,LOD值为5.1,解释表型变异率是3.8%;QBph4位于第4号染色体RM16605-RM16717之间,LOD值为28.7,解释表型变异率是29.4%;QBph6位于第6号染色体RM276-RM527之间,LOD值为2.7,解释表型变异率是7.1%;3个QTL的联合贡献率为40.3%。Qbph4可解释表型变异率最大,初步判断Qbph4可能是一个控制褐飞虱抗性的主效基因。     

利用染色体片段置换系定位水稻粒型QTL

水稻粒型是衡量稻米外观品质的重要指标之一,鉴定和定位水稻粒型QTL对开展水稻粒型分子育种具有重要意义.本研究以8个染色体片段置换系为材料,选用分布水稻12条染色体上的153个SSR标记检测染色体片段置换系的置换片段,采用代换作图法对控制水稻粒型的3个主效QTL进行定位.结果表明:153个SSR标记中有104个标记在亲本间具有多态性,多态率为68.0%;8个染色体片段置换系在第3和第5染色体分别有6个和2个置换片段,置换片段长度分别为14.8 cM、16.6 cM、 15.5 cM、18.9 cM、29.1 cM、35.0 cM、17.9 cM 和17.0 cM,平均长度为20.6 cM;8个置换片段上共鉴定出3个粒型QTL,控制粒长的qGL-3-1 和qGL-3-2分别被界定在水稻第3染色体RM5551与RM6832及RM6832与RM3513之间,遗传距离分别为14.8 cM和5.3 cM的范围内,控制粒宽的qGW-5被界定在水稻第5染色体RM267与RM169之间遗传距离约11.7 cM的范围内.利用染色体片段置换系能准确地定位水稻粒型QTL,qGL-3-1、qGL-3-2和qGW-5的鉴定和初步定位为其进一步精细定位及分子标记辅助选择奠定了基础.     

利用染色体片段置换系定位水稻抗纹枯病QTLs

为检测水稻纹枯病抗性基因位点,采用牙签接种法对籼稻9311和粳稻日本晴以及由它们构建的119个染色体单片段置换系进行纹枯病抗性鉴定,并使用该群体的分子连锁图谱进行数量性状座位（QTL）分析。共检测到3个纹枯病相关 QTL（qsb8-1, qsb8-2和 qsb8-3）,分别位于第8染色体相邻标记 RM3262、RM5485和 RM3496附近,所在遗传区间分别为81.7cM-91.7cM、91.7cM-108.1cM和108.1cM-119.6cM。其中 qsb8-2的加性效应为负值,表明感病亲本携带的该片段可以增强纹枯病抗性;qsb8-1和qsb8-3的加性效应为正值,表明感病亲本携带的该片段减弱了纹枯病抗性。     

Validation of qGSIO,a quantitative trait locus for grain size on the long arm of chromosome 10 in rice (Oryza sativa L.)

Grain size is a major determinant of grain weight and a trait having important impact on grain quality in rice.The objective of this study is to detect QTLs for grain size in rice and identify important QTLs that have not been well characterized before.The QTL mapping was first performed using three recombinant inbred line populations derived from indica rice crosses Teqing/IRBB lines,Zhenshan 97/Milyang 46,Xieqingzao/Milyang 46.Fourteen QTLs for grain length and 10 QTLs for grain width were detected,including seven shared by two populations and 17 found in one population.Three of the seven common QTLs were found to coincide in position with those that have been cloned and the four others remained to be clarified.One of them,qGS10 located in the interval RM6100-RM228 on the long arm of chromosome 10,was validated using F_(2:3) populations and near isogenic lines derived from residual heterozygotes for the interval RM6100-RM228.The QTL was found to have a considerable effect on grain size and grain weight,and a small effect on grain number.This region was also previously detected for quality traits in rice in a number of studies,providing a good candidate for functional analysis and breeding utilization.     

野生稻渗入系苗期耐铝QTL定位分析(英文)

本研究以元江普通野生稻与优良栽培稻亲本特青配制的野生稻染色体片段代换系为材料,在幼苗生长阶段,利用室内、室外株高、干重抑制率的表型数据检测与耐铝相关的QTL,分别检测到11、18、14和5个与耐铝相关的QTL,分布于不同的染色体上,室内、室外株高抑制率的表型数据检测结果表明,位于第8染色体RM38附近和第12染色体RM277附近贡献率较大,分别为12%和11%,分析是主效QTL。室内、室外干重抑制率的表型数据检测到的最大QTL的贡献率分别只有9%和8%,未检测到主效QTL。重复检测到的QTL分布于第7、8、9、11和12染色体上。第8染色体上有2个QTL,其中RM310附近的QTL被三次重复检测到,其余的被检测到二次,分析这些QTL是稳定的QTL。     

利用DH和IF_2两个群体进行小麦粒重、粒型和硬度的QTL分析

【目的】检测控制小麦粒重、粒型和硬度加性和显性QTL,解释控制这些性状的分子遗传基础。【方法】以小麦品种花培3号、豫麦57构建的包含168个株系的DH群体和由其构建的包含168个株系的IF2群体为材料,结合含有368个位点的分子遗传图谱,对5个环境的DH群体以及2个环境的IF2群体的千粒重、粒型和硬度数据进行QTL分析。【结果】共检测到控制千粒重、粒长、粒径和硬度的35个加性效应和18对上位效应QTL,包括控制千粒重的8个加性效应位点以及5对上位性位点,控制粒长的10个加性效应位点以及6对上位性位点,控制粒径的10个加性效应位点以及6对上位性位点,控制硬度的7个加性效应位点以及1对上位性位点。其中,控制粒重的Qtkw6A在DH和IF2群体中都能检测到,而且既有加性效应又有显性效应,加性效应的贡献率在2个群体内分别为9.39%和11.75%,显性效应的贡献率为1.37%。控制粒径的Qgd6A也在DH和IF2群体中检测到,加性效应贡献率分别为15.02%和15.03%,而且与控制粒长的Qgl6A为同一基因位点,在DH和IF2群体中对粒长的加性效应贡献率分别为14.96%和15.10%。【结论】小麦的千粒重和粒型的遗传主要受加性效应控制,同时也受上位效应影响。硬度主要受位于5D染色体短臂上一个主效基因控制,同时受其它微效基因以及上位性影响。本研究检测到的一些重要QTL可用于相关性状的分子标记辅助选择育种,用IF2群体检测到的显性效应QTL及具有显性×加性、加性×显性及显性×显性效应的QTL可为有关性状杂种优势的研究提供参考。     

Molecular Mapping of QTLs for Cold Tolerance at the Budburst Period in Rice

The quantitative trait loci (QTLs) for cold tolerance at the budburst period (CTBP) was identified using a F2:3 population including 200 lines derived from a cross of indica and japonica Milyang23/Jilengl. A molecular linkage map of 97 SSR markers was constructed using interval mapping and covered a total length of 1 357.3 cM with an average distance of 13.99cM, between adjacent markers in rice genome. The CTBP of F3 lines was evaluated at 5℃, and the survival seedling rate after treating under low temperature at the budburst period was used as cold tolerance index for CTBP. A continuous distribution near to normal for CTBP was observed in F3 lines, CTBP is a quantitative trait which was controlled by some genes. Three QTLs on chromosomes 2, 4 and 7 which are associated with CTBP were detected on location of RM6-RM240, RM273-RM303, RM214-RMll, respectively,which explained the range of the observed phenotypic variance from 11.5 to 20.5%. qCTBP4detected on RM273-RM303 of chromosome 4 explained 20.5% of the observed phenotypic variance. The effect of qCTBP4's allelic gene comes from Jileng 1.     

利用2个相关群体定位和比较水稻株高与抽穗期QTL

利用一个共同亲本构建的2个重组自交系群体对控制水稻株高和抽穗期进行基因定位和比较分析。结果表明:2个群体共定位到11个控制抽穗期的数量性状位点(QTLs)和11个株高QTLs。控制抽穗期的主效QTL在珍汕97/南洋占群体内位于第7染色体RM500-RM445标记之间;在珍汕97/德陇208群体内定位于第7染色体RMRG4499-RM445标记之间。而控制株高的主效QTL在2个群体中分别定位于第1染色体RM472-RM104之间和第7染色体MRG4499-RM445之间。比较定位结果发现,抽穗期主效QTL在2个群体内都被定位于第7染色体中部位置并且有共同标记RM445,很有可能是同一个基因。说明抽穗期是由主效QTL控制的数量性状,遗传稳定。株高主效QTL在珍汕97/南洋占群体内被定位于第1染色体接近末端标记RM104附近。在珍汕97/德陇208群体内则定位于第7染色体,与该群体控制抽穗期QTL共享RM445标记。     

水稻芽期耐冷性QTL的分子定位

 以籼粳交密阳23号/吉冷1号的F2：3 代200个家系作为作图群体，构建了一张含有97个微卫星 （SSR）标记的分子连锁图谱。在5℃低温条件下，对F3家系进行芽期耐冷性鉴定，并利用SSR标记进行了芽期耐冷性数量性状位点（QTL）分析。研究结果表明，芽期耐冷性在F3家系群中呈单峰连续分布，表现为由多基因控制的数量性状；共检测到与芽期耐冷性有关的QTL 3个，分别位于第2、4 和7染色体上，对表型变异的贡献率范围为11.5%～20.5%。其中，位于第4染色体RM273～RM303的qCTBP4对表型变异的贡献率最大。     

Identification of quantitative trait loci and candidate genes associated with ABA sensitivity in common wild rice(Oryza rufipogon Griff.)

Abscisic acid(ABA),as one of the foremost signaling molecules in plants,is an important hormone which plays versatile functions in regulating developmental process and adaptive stress process.A set of introgression lines were previously generated via a backcrossing program using an elite indica cultivar rice Teqing(O.sativa L.) as recipient and an accession of Yuanjiang common wild rice(O.rufipogon Griff.) as donor.In this study,the previously developed introgression lines were evaluated for ABA sensitivity.Here we reported that a total of 14 quantitative trait loci(QTLs) associated with ABA sensitivity were identified.An ABA sensitive introgression line,YIL53,was identified and characterized.Physiological characterization,including chlorophyll content,malondialdehyde content,soluble sugar content,and stomata movement,demonstrated that YIL53 exhibited the characteristics associated with ABA sensitivity.Genotypic analysis revealed that YIL53 harbored one QTL related to ABA sensitivity,q ASS1-2,which was located on chromosome 1 within one introgressed segment derived from the Yuanjiang common wild rice.Furthermore,the qASS1-2 was finally narrowed down to a 441-kb region between simple sequence repeats(SSR) marker RM212 and single nucleotide polymorphism(SNP) marker M3 using the segregation population derived from the cross between Teqing and YIL53,and three candidate genes associated with ABA sensitivity were identified using a strategy combined gene expression analysis with QTL mapping.Identification of the QTLs related to ABA sensitivity and characterization of the ABA sensitive line YIL53 would provide a helpful basis for isolating novel genes related to ABA sensitivity.     

水稻抽穗期QTL鉴定及重叠群作图

以40个单片段代换系(Single Segment Substitution Lines,SSSLs)为试材,分别在2012和2013年对水稻抽穗期QTL进行分析,其中30个SSSLs能够在两年中重复检出,占检出SSSLs的78.9%。经重叠群作图分析,鉴定出11个抽穗期QTL,分别位于第1、2、3、4、6、8、10染色体上,这些QTL具有较大的加性效应,且受环境影响较小。