水稻低温发芽力的QTL定位

以珍汕97B与多年生稻种质AAV002863的DH群体(198个株系)构建了包含140个SSR标记的连锁图谱,检测了影响水稻低温发芽力性状的数量性状座位（QTL）。15℃下处理6 d,两亲本珍汕97B与多年生稻AAV002863的发芽率分别为79.7%和30.1%,DH群体间的发芽率变化在0%~100%。QTL定位分析检测到2个与低温发芽力相关的基因座,分别位于第3和第10染色体上,贡献率分别为12.6%和12.9%,增效等位基因分别来自多年生稻AAV002863和珍汕97B。上位性分析结果显示,第1与第10染色体上存在影响低温发芽力的互作位点,其互作可以提高低温发芽力,参与互作的第10染色体上的位点也具有加性主效应。     

Identification of QTLs for Rice Cold Tolerance at Plumule and 3-Leaf-Seedling Stages by Using QTLNetwork Software

A doubled haploid(DH)population consisted of 120 lines,derived from a cross between an indica variety,TN1, and a japonica variety,Chunjiang 06,was used to identify QTLs controlling rice cold tolerance at the plumule and 3-leaf-seedling stages by using the QTLNetwork software.The percentages of normal plumules after 4°C treatments for 7 d, 9 d,11 d,and 14 d,as well as the cold stress tolerance index(CSTI)and the withering index(WI)of rice seedling were investigated.A total of five single-effect QTLs,each for percentages of normal plumules after 4°C treatments for 9 d,11 d and 14 d,and CSTI and WI,respectively were identified.The QTLs for the percentages of normal plumules after low temperature treatments for 9 d,11 d and 14 d were on chromosomes 4,2 and 11,accounting for 14.1%,17.3%and 21.5%of the phenotypic variation,respectively.QTLs for CSTI and WI were on chromosomes 10 and 1,respectively.Two pairs of epistatic loci were identified,but none of the epistatic loci involved the single-effect QTLs.The RM528-RM340 interval on chromosome 6 interacted with the RM278-RM3919B interval on chromosome 9 for CSTI,and the epistatic interaction accounted for 17.7%of the phenotypic variation.A pair of epistatic loci was identified for WI,the RM246-RM5461 interval on chromosome 1 interacted with the ISA-RM447 interval on chromosome 8,which accounted for 22.6%of the phenotypic variation.     

基于QTL定位的水稻有效穗数杂种优势预测

以水稻杂交组合珍汕97B×明恢63所衍生的永久F2（IF2）作图群体为遗传材料,采用QTLNetwork 2.0定位软件对有效穗数进行了QTL分析,共检测到8个QTL,分布于6条染色体上。同时根据有效穗数的QTL遗传效应,估算了F1、F2和F3三个杂种世代的有效穗数杂种优势,在预测普通杂种优势的同时,也对环境互作杂种优势进行了预测。上位性QTL对有效穗数杂种优势的形成有重要的贡献。表明基于QTL定位结果的杂种优势预测方法有助于分子标记辅助选育强优势组合。     

不同遗传背景下水稻剑叶形态性状的QTL分析

以典型的籼粳交窄叶青8号/京系17的加倍单倍体（DH）群体和籼籼交珍汕97/明恢63的重组自交系（RIL）群体为材料,并应用这两种群体已构建的分子图谱,对剑叶形态性状中的叶面积、周长、叶长、叶宽、长宽比等进行了QTL分析。在这两个群体中,剑叶的这些形态性状均呈连续性分布,存在一定数量的超亲分离。在DH群体中, 4个剑叶性状共检测到8个QTL,分布在4条染色体上,其中第4、8染色体上各有1个QTL同时影响了叶长、 叶周长和面积。 在RIL群体中,5个剑叶性状共检测到16个QTL,分布在5条染色体上。其中第1染色体上有1个QTL同时影响叶长、叶周长、长宽比3个性状,第6染色体上有2个影响叶面积的QTL同时也影响叶宽,还有1个QTL同时影响叶长、叶周长2个性状,第11染色体上有1个QTL同时影响叶长、叶周长、叶面积3个性状。研究表明,不同群体的QTL初级定位结果存在较大差异,影响叶片相关性状的一些QTL位于同一染色体的相同或者相邻区域上。     

水稻籼粳杂种育性的QTL分析

 以籼稻保持系珍汕97B和粳稻保持系辽91B为亲本,构建了一个包含176个单株的F2群体及123个SSR标记的遗传图谱,在3种环境下联合检测控制花粉育性和小穗育性的QTL。共检测到3个控制花粉育性的主效应（加性效应和显性效应）QTL（qPF3、qPF5和qPF6）和4个控制小穗育性的主效应QTL（qSF3、qSF5、qSF6和qSF8）,其中qPF5与qSF5、qPF6与qSF6均为同一个QTL,为重要的育性QTL。另外,检测到3对花粉育性和4对小穗育性QTL间互作,说明上位性效应对籼粳杂交后代的育性具有重要作用。     

应用微卫星标记定位水稻恢复系密阳46的主效和微效恢复基因

应用由704个株系组成的珍汕97A/(珍汕97B/密阳46)F6测交群体,针对水稻第10染色体和第1、11染色体短臂构建了微卫星标记连锁图谱,检测到控制野败型细胞质雄性不育育性恢复的4个QTL,其中位于第10染色体长臂中下部的Rf4具有主效效应,位于第1染色体短臂的Rf3具有较大效应,位于第10染色体长臂近着丝粒处的qRf10和第11染色体短臂近着丝粒处的qRf11表现出微效作用。研究还表明,在主效基因Rf4存在时,其他3个基因仍具有提高结实率的作用,但在Rf3和Rf4同时存在时,qRf10和qRf11的效应不明显。     

Identification of QTL Affecting Protein and Amino Acid Contents in Rice

The phenotypes of protein and amino acid contents were measured in an F9 recombinant inbred line population derived from a cross between Zhenshan 97B and Delong 208. A total of 48 and 64 QTLs were identified in 2004 and 2005, respectively. The contribution of each QTL to the phenotypic variation ranged from 4.0% to 43.7%. Most QTLs co-localized, forming 29 QTL clusters on the chromosomes with three major ones detected in both years, which were mapped on chromosomes 1, 7 and 9, respectively. The two QTL clus...     

水稻第6染色体短臂株高及产量性状QTL的分解

针对第6染色体短臂上一个对产量性状遗传具有重要作用的区间RM587-RM19715,从珍汕97B/密阳46重组自交系群体中筛选到1个剩余杂合体,自交衍生获得一个由195个个体组成的F2群体,检测控制株高和产量性状的QTL。经分析,在目标区间的上部和下部分别检测到1个QTL簇,分别对除单株穗数以外的产量性状因子具显著作用,单个QTL对群体性状表型变异的贡献率为5.0%~55.5%。将第6染色体上的产量性状QTL分解到更小的区间中,为产量性状QTL的精细定位和克隆打下了基础。     

水稻苗期盐胁迫下叶绿素荧光参数的QTL分析

 应用247个株系组成的珍汕97B/密阳46重组自交系群体及其相应的含250个分子标记的高密度分子遗传图谱,通过复合区间作图法,对苗期水培和盐胁迫条件下水稻叶片叶绿素荧光参数进行了数量性状座位（QTL）分析。检测到控制水稻叶片叶绿素荧光参数（Fo、Fm和ΦPSⅡ）的7个主效应QTL,分布在水稻的第1、4、5和11染色体上,贡献率为598%～10.74%。其中,控制水培条件下Fm的QTL与控制盐胁迫下Fo的QTL均位于第5染色体的CDO82-RG413标记区间,说明此区间的QTL具有多效性,可同时影响Fm、Fo两个叶绿素荧光参数。     

水稻苗期发根力的QTL和上位性分析

以典型籼粳交(窄叶青8号/京系17)F[sub]1[/sub]花培加倍的DH群体为材料,采取水上栽培方法,考察苗期根系发根力。利用已构建的分子连锁图谱,采用基于混合的线性模型复合区间作图法对水稻苗期发根力进行QTL和上位性分析。在第3染色体的C63-CT125之间检测到1个发根力的主效QTL,同时也检测到影响发根力的5对上位性效应基因座,分别位于第2、3、5、6、7、12染色体上,其中影响根长、根数上位性效应各有两对区间,有一对既影响根长,又影响根数。     

Mapping QTL for Heat-Tolerance at Grain Filling Stage in Rice

A mapping population of 98 lines (backcross inbred lines, BILs) derived from a backcross of Nipponbare/Kasalath// Nipponbare was planted at two experimental sites, Nanjing and Nanchang, and treated with high and optimal temperature during grain filling, respectively. The grain weight heat susceptibility index [GWHSI= (grain weight at optimum temperature-grain weight at high temperature) / grain weight at optimum temperature ×100] was employed to evaluate the tolerance of rice to heat stress. A genetic linkage map with 245 RFLP markers and a mixed linear-model approach was used to detect quantitative trait loci (QTLs) and their main effects, epistatic interactions and QTL×environment interactions (Q×E). The threshold of LOD score=2.0 was used to detect the significance of association between marker and trait. A total of 3 QTLs controlling heat tolerance during grain filling were detected, on chromosomes 1, 4 and 7, with LOD scores of 8.16, 11.08 and 12.86, respectively, and they explained the phenotypic variance of 8.94, 17.25 and 13.50 %, correspondingly. The QTL located in the C1100-R1783 region of chromosome 4 showed no QTL×environment interaction and epistatic effect, suggesting that it could be stably expressed in different environments and genetic backgrounds, and thus it would be valuable in rice breeding for heat tolerance improvement. This QTL allele, derived from Kasalath reduced 3.31% of the grain weight loss under heat stress. One located between R1613-C970 on chromosome 1 and the other between C1226-R1440 on chromosome 7, with additive effect 2.38 and 2.92%, respectively. The tolerance alleles of both these QTLs were derived from Nipponbare. Both of these QTLs had significant QTL×environment interactions, and the latter was involved in epistatic interaction also. Eight pairs of epistatic effect QTLs were detected, one pair each on chromosomes 1,2,3, 5, 7, 8, 10 and 12. The results could be useful for elucidating the genetic mechanism of heat-tolerance and the development of new rice varieties with heat tolerance during grain filling phase.     

Relationship Between Coleoptile Length and Drought Resistance and Their QTL Mapping in Rice

By using a set of recombinant inbred line(RIL)population involving in 195 lines derived from a cross of Zhenshan 97B (lowland variety)and IRAT109(upland variety),the correlation analysis between coleoptile length(CL)and drought resistance index (DRI)and their QTL identification were conducted.There existed a significantly positive relationship between CL and DRI with the correlation coefficient of 0.2206**under water stress conditions.Under normal and water stress conditions,a total of eleven and four QTLs for CL and DRI,respectively,were detected on chromosomes 1,2,4,5,6,7,9,11 and 12 by using a linkage map including 213 SSR markers,which explained 4.84%to 22.65%of phenotypic variance.Chromosomes 1 and 9 possessing the QTLs for DRI harbored simultaneously QTLs for CL,and qCL9 shared the same chromosome location with qDRI9(RM160-RM215).Comparing the QTLs related to drought resistance in other studies,QTLs for CL and DRI were located in the same or adjacent marker interval as those related to root traits,such as number,dry weight,depth,and length of root.Moreover,sixteen and three pairs of epistatic loci for CL and DRI were found,which accounted for 56.17%and 11.93%of the total variation in CL and DRI,respectively.     

Mapping QTLs for Drought Tolerance at Seedling Stage in Rice Using Doubled Haploid Population

QTLs for drought tolerance at the rice seedling stage were analyzed using a doubled haploid (DH) population consisted of 251 lines from the cross between a japonica parent Maybelle and an indica parent Baiyeqiu. A genetic linkage map with 226 SSR marker loci was constructed. Single-locus analysis following composite interval mapping (CIM) detected a total of five QTLs located on five different chromosomes of rice. Four QTLs were also detected following two-locus analysis, resolving two pairs of epistatic QT...     

水稻籼粳交DH群体中影响白背飞虱抗虫性QTL的检测

分析了水稻籼粳交加倍单倍体(DH)群体中影响白背飞虱抗虫性和感虫性的QTL.虽然DH株系的亲本窄叶青8号和京系17没有拒取食抗性,但是白背飞虱在6个DH株系中的取食受到了强烈的抑制,可能属超亲分离.在第3染色体的粳型片段中检测到1个影响蜜露分泌的微效QTL.粳稻亲本京系17具有杀卵抗性.DH株系中的杀卵特性是通过叶鞘上杀卵反应产生的坏死症状表现的.在DH株系分蘖早期和中期,将4个杀卵作用的QTL定位在第1、2、6和8染色体的粳型片段上.出现在分蘖中期的另一个QTL被定位在第9染色体的籼型片段上.在分蘖盛期至孕穗期,杀卵位点减少至2个.整个试验期间对每个DH株系的最高杀卵级别的分析显示,在染色体2、6和9上共有4个QTL.两个主效QTL位于近邻第6染色体的粳型片段.在第1、3和5染色体上检测到3个影响第2代白背飞虱若虫密度的QTL.第3染色体上起主要作用的QTL源自粳稻亲本;第5染色体上的微效QTL源自籼稻亲本.两个白背飞虱为害的QTL位于第8和第10染色体的籼型片段,另一个QTL位于第3染色体的粳型片段.这些QTL被认为与水稻品种对白背飞虱田间抗性表达有关.     

水稻穗芽相关性状的QTL定位

利用305个株系组成的源自籼稻品种中156和谷梅2号的重组自交系群体进行了水稻穗芽性状的QTL检测和遗传效应分析。以穗芽指数及相关指标作为穗芽性状的表型值,采用QTL Mapper 1.01统计软件进行QTL定位和上位性分析,共检测到控制穗芽指数的3个加性效应QTL,分别位于第2、9、11染色体上;控制穗芽速率的加性效应QTL 3个,分别位于第1、3、6染色体上;控制穗穗芽率的加性效应QTL 3个,分别位于第1、9、10染色体上;控制粒穗芽的加性效应QTL 2个,分别位于第9、11染色体上。还检测到3对影响穗芽指数的加性×加性上位性互作效应QTL;3对控制穗芽速率的上位性QTL和3对控制粒穗芽率的上位性QTL。     

Development and Application of SCAR Markers for Discriminating Cytoplasmic Male Sterile Lines from Their Cognate Maintainer Lines in Indica Rice

The DNA fragments about 1 600 bp were amplified using random amplified polymorphism DNA (RAPD) primer OPA12 with the templates of mitochondrial DNA of Zhenshan 97A and Zhenshan 97B,and were sequenced.The nucleotide sequences and lengths of the fragments from Zhenshan 97A and Zhenshan 97B showed no difference.The precise length of the fragment was 1 588 bp.Sequence characterized amplification region (SCAR) primers were then developed to discriminate the cytoplasmic male sterile (CMS) lines and their maintainer lines.A specific 1 588 bp fragment could be amplified with SCAR primers,CHI19F2/CHI19R2 and CHI20F3/CHI23R3,in the mitochondrial DNA of Zhenshan 97A,but not Zhenshan 97B.Furthermore,the specific fragment could be also amplified from the total DNA from green leaf tissues of Zhenshan 97A with SCAR primers,but not Zhenshan 97B.With the corresponding primers,the specific fragment could also be amplified from the total DNA of green leaves of other two CMS lines with wild abortive type cytoplasm (CMS-WA),namely Zhenpin A and Tianfeng A,but not in their maintainer lines.Moreover,using total DNA as template,each of the four pairs of SCAR primers could also be used to amplify the 1 588 bp fragment in CMS-ID (Indonesia paddy type) line Ⅱ-32A,but not in II-32B,and the specific fragment was amplified from the DNA of both F1 and F2 seedlings of Shanyou 63.The results of detecting the genetic purity of a man-made mixture of the seeds of Zhenshan 97A using CHI20F3/CHI23R3 were completely consistent with the phenotypes.Taken together,these results indicated that the specific 1 588 bp-fragment amplified by CHI20F3/CHI23R3 was the unique amplification products of CMS mitochondrial DNA,and could be used to distinguish CMS-WA and CMS-ID lines from their corresponding maintainer lines at the seedling stage.     

水稻耐光氧化特性的QTL定位

利用由127个株系组成的来源于籼稻品种窄叶青8号和粳稻品种京系17的加倍单倍体群体,以耐性指数和敏感性指数为指标,采用QTL Mapper 1.6统计软件进行水稻耐光氧化反应特性的QTL定位和上位性分析,共检测到控制耐性指数的1个加性效应QTL,位于第3染色体上;控制敏感性指数的加性效应QTL 5个,分别位于第1、1、6、8和9染色体上。还检测到3对影响耐性指数的加性×加性上位性互作效应QTL和5对敏感性指数的上位性QTL。还对41个水稻材料进行了光氧化实验筛选。     

水稻灌浆期耐热害的数量性状基因位点分析

 利用由98个家系组成的Nipponbare / Kasalath // Nipponbare回交重组自交系群体及其分子连锁图谱，以粒重感热指数\[（适温粒重-高温粒重）/适温粒重×100\]为评价指标，采用混合线性模型的QTL定位方法，对水稻灌浆期耐热性的主效、上位性数量性状基因位点及其与环境的互作进行分析。共检测到3个灌浆期耐热性主效QTL，分别位于第1、4和7染色体上，LOD值为8.16、11.08和12.86，贡献率8.94%、17.25%和13.50%。其中位于第4染色体标记C1100-R1783之间的QTL，没有显著的上位性和环境互作效应，表明在不同环境和遗传背景中的表达较为稳定，在水稻耐热性育种中可能具有较大的利用价值，其耐热性等位基因来自亲本Kasalath，高温热害时可减少粒重损失3.31%。位于第1染色体标记R1613-C970之间的QTL和第7染色体标记C1226-R1440之间的QTL，耐热性等位基因来自亲本Nipponbare，分别可减少粒重损失2.38%和2.92%。这两个QTL均具有与环境的互作效应，其中第7染色体上的QTL还和其他基因位点有互作。检测到8对加性×加性上位性互作QTL，分布于第1、2、3、5、7、8、10和12染色体上。没有检测到上位性QTL与环境的互作效应。     

水稻种子低氧发芽力的QTL定位和上位性分析

利用35份水稻品种资源,评价了在不同水深、温度等低氧条件下的种子萌发情况,表明水温30℃、水深0.2 m下黑暗萌发5 d为最佳鉴定方法,并以此条件下水稻种子萌发的芽长为鉴定指标,评价了359份水稻品种低氧发芽力地区间、籼粳间的差异。进一步利用81个Kinmaze/DV85 重组自交系群体进行了水稻低氧发芽力数量性状位点分析, 在第1、2、5、7染色体上检测到5 个低氧发芽力QTL,其中第5染色体上存在2个QTL,各QTL的贡献率为10.5%～19.6%。同时进行上位性分析,检测到3对互作位点,分别位于第2、3、5、11染色体上,其中位于第3染色体上标记C563-X182之间的位点与第5染色体上标记R830-X208之间的位点的互作贡献率高达48.78%。     

Molecular mapping of QTLs for gluten strength as measured by sedimentation volume and mixograph in durum wheat (Triticum turgidum L. ssp durum)

Quantitative trait loci (QTLs) responsible for gluten strength measured by SDS-sedimentation volume (SV), mixograph and grain protein content (GPC) were located on the molecular linkage map of a durum wheat recombinant inbred line population. QSv.macs-1B.1 flanked by Xgwm550–Glu-B3 was the most consistent QTL for SV identified in all the environments. The same QTL was also associated with mixograph peak energy, peak time and total energy. The Glu-B1 locus was at the center of another QTL responsible for SV, while, Glu-B2 influenced SV as well as mixograph peak energy and peak time. Apart from glutenin coding loci, QTLs influencing mixing parameters and GPC were located in three other marker intervals Xwmc48.2–Xpsp3030 (4B), Xgwm573–Xbarc231.1 (7A) and Xgwm46–Xgwm540.1 (7B). A total of 26 main effect QTLs and 10 digenic epistatic interactions (QQ) for quality traits were distributed over 11 chromosomes. Out of these, seven main effect QTLs and three QQ interactions were involved in interactions with environments (QE, QQE). The results indicated that along with chromosome 1B, chromosomes 4B, 7A and 7B are also important for improvement of gluten strength and GPC in durum wheat.