粳稻野败型细胞质雄性不育恢复系SWR78的恢复基因定位

 利用野败(WA)型粳稻广亲和不育系苏秋A和广亲和广谱型恢复系SWR78配组,根据F2与BC1F1群体的育性分离情况,初步推测WA型苏秋A的育性恢复至少由3对基因控制。选取F2群体中无染色花粉植株,采用隐性基因组分析法进行恢复基因定位,将其中1个主效基因Rf4定位于第10染色体长臂上,与标记RM5629、RM5373、STS10 17和STS10 18分别相距0.17、0.03、0.03和0.07 cM。Rf4位于标记RM5373与STS10 17之间,两标记间的物理距离为78 kb。     

一个水稻金黄色颖壳和节间基因的遗传定位

R68是带有金黄色颖壳和节间标记的籼稻恢复系。对来源于组合中9A/R68 的F2群体的遗传分析表明,R68的金黄色颖壳和节间性状由1对隐性基因控制。利用SSR分子标记,采用隐性群体分析法,把金黄色颖壳和节间基因定位在第3染色体上,位于RM1230、RM7000和RM227、RM514之间,遗传距离分别为8.7、3.3、2.7和4.7 cM,暂将该基因命名为 gh 5。     

水稻广谱强恢复系种质GR38雄性不育恢复性的QTL定位

GR38是自育的偏粳型广谱强恢复系种质,利用GR38分别与籼型不育系G46A和粳型不育系光A杂交的F2群体,应用集团分离分析方法和SSR标记对GR38的育性恢复基因进行分析。在组合G46A/GR38的F2群体中检测到2个独立的育性恢复QTL,分别位于第1染色体短臂上的SSR标记RM1331与RM3740之间和第1染色体长臂上的SSR标记RM5310与RM486之间;在组合光A/GR38的F2后代群体中只检测到1个育性恢复QTL,位于第1染色体短臂上的SSR标记RM3740与RM490之间。在两群体中均检测到的位于第1染色体短臂的育性恢复QTL,可能与已报道的Rf3等位,而位于第1染色体长臂上的恢复基因的可能为GR38上特有的新位点,命名为qRf(G-2)。     

应用近等基因系初步定位粳稻孕穗期的耐冷基因

 在昆明低温冷害条件下对十和田×(十和田5/昆明小白谷BC4F5)的BC5F2群体进行了耐冷性状的遗传研究。结果显示，穗期耐冷性受贡献率较大的基因控制。用平均分布于12条染色体的164个SSR标记对十和田、昆明小白谷、近等基因系池（NILP）进行筛选，在第5染色体长臂末端有2个SSR标记的扩增产物在十和田与昆明小白谷、NILP间有多态性。用这2个多态性标记对群体进行分子标记定位，单向方差分析表明RM31与耐冷基因连锁。再在RM31附近合成12个SSR标记在轮回亲本（RP）、近等基因系（NIL）间进行多态性筛选，只有RM7452有多态性, 单向方差分析表明该标记与耐冷基因连锁。耐冷基因与RM7452、RM31的遗传距离分别为4.8 cM和8.0 cM，主穗结实率能解释表型变异的10.50%；实粒数能解释表型变异的5.10%。暂将这个耐冷基因定名为Ctb(t)。     

大豆M型细胞质雄性不育恢复基因标记定位

鉴于与恢复基因紧密连锁的分子标记在分子辅助选择育种中的应用前景,采用SSR标记法定位大豆CMS恢复系WR016的恢复基因.根据(W931A×WR016)F1、F2的植株育性,分析表明大豆M型不育系统为单基因配子体不育.由于大豆M-CMS恢复系WR016的恢复基因定位在A1连锁群上,利用A1连锁群上的大豆SSR引物对不育系W931A和恢复系WR016构建的F,分离群体进行分析,获得了与恢复基因连锁的三个标记Satt684、Satt276和Sat545,遗传距离分别为29.5cM、10.7 cM和14.1 cM.虽然10.7 cM还是一个较远的距离,但为进一步精确定位恢复基因,并最终克隆恢复基因打下了基础.     

小麦雄性不育系AL18A育性恢复基因的QTL定位

为加快AL型杂交小麦的发展,以不育系AL18A、恢复系99AR144-1及二者杂交F2代群体为材料,选用SSR标记和分离群体分组分析法进行育性恢复基因的QTL定位。结果表明,育性恢复由主效和微效基因共同控制,采用复合区间作图法分析,在1B染色体上检测到了1个主效恢复基因QTLqRf-1B-1,在5AL染色体上检测到了1个微效QTLqRf-5A-1。qRf-1B-1位于SSR标记Xbarc8与Xgwm413之间,与两标记的遗传距离分别为0.85cM和2.00cM,LOD值为14.06,加性效应为18.87,可解释22.43%的表型变异;qRf-5A-1位于SSR标记Xgwm595与Xgwm410之间,与两标记的遗传距离分别为10.00cM和0.10cM,LOD值为3.18,加性效应为12.32,可解释5.44%的表型变异。     

大豆M型细胞质雄性不育恢复基因SSR标记初步定位

鉴于细胞质雄性不育(Cytoplasmic Male Sterility,CMS)在作物杂种优势利用中的良好应用前景及分子标记对恢复系选育的应用价值,试验采用SSR分子标记对大豆CMS恢复系WR016恢复基因进行初步定位.利用197对大豆SSR引物对不育系W931A和恢复系WR016单株进行多态性筛选,52对引物在双亲间表现多态性,多态性频率26.39%,进一步利用这52对引物对10株不育系W931A和恢复系WR016单株、不育基因池、可育基因池和半不育基因池进行分析,表明位于A连锁群上的Satt276表现出良好的多态性.再利用合成的Satt276附近的引物进行分析,表明Satt684和Satt572也有良好的多态性.据此,可将大豆M-CMS恢复系WR016的恢复基因初步定位在A连锁群上.     

水稻抽穗扬花期耐热QTL(qHTH5)定位及其遗传效应分析

对元江普通野生稻(Oryza rufipogon Griff.)(简称元江普野)荷花塘3号为供体、籼稻(O.sativassp.indica)恢复系蜀恢527为轮回亲本构建的种间近等基因系群体进行数量性状位点(QTL)分析,在近等基因导入系YJ10-03-01中鉴定了一个抽穗扬花期耐热QTL。利用均匀分布在水稻12条染色体上的360个SSR标记检测近等基因系YJ10-03-01和籼稻恢复系蜀恢527,共获得9个多态性标记。单标记分析表明第5染色体短臂上的多态性标记与抽穗扬花期耐热性极显著相关。进一步在人工气候室模拟高温条件下处理YJ10-03-01与蜀恢527杂交得到F2分离群体(1027个单株)并进行SSR标记分析,以水稻结实率为耐热指标,利用复合区间作图方法在第5染色体短臂上检测到一个抽穗扬花期耐热性QTL,暂命名为qHTH5。该QTL在F2及F3世代分别解释8.6%和19.4%的表型变异。在F3世代,继续利用目标区间标记RM7320和RM7444之间的SSR标记鉴定纯合重组体,利用置换作图法将QTL定位在约304.2kb之内(RM592-RM17921)。     

来自莫迦小麦(T. macha)的T型恢复基因Rf3和K型不育基因rfv1的SSR标记分析

为了建立非1B/1R类型K型小麦细胞质雄性不育系的分子标记辅助选育技术体系,对基础遗传材料Tm3314来自莫迦小麦1BS染色体的T 型恢复基因Rf3和K型不育基因rfv1进行了分子标记定位.以Tm3314和T型不育系T504A的杂交F2代作为定位群体,利用分离集团分析法(BSA),从1BS染色体上10对SSR引物中筛选出与目的基因连锁的2个SSR标记Xbarc8和Xgwm18.然后结合(T504A/Tm3314)F2群体在T型细胞质下的育性分离情况和F2可育株与K型不育系K119A测交所得的K型细胞质下的育性结果,运用Mapmaker 3.0b软件进行连锁分析,结果表明,Xbarc8和Xgwm18与Rf3基因的遗传距离分别为5.5 cM和8.1 cM,与rfv1基因的遗传距离分别为22.2 cM和19.6 cM,且2个SSR标记位于两个育性基因之间.     

粳型短日不育新种质5021S育性基因的定位

粳型短日不育新种质5021S育性转换表现为"长光高温下可育,短光低温下不育"的反(向)光、温敏核不育特性。以5021S/轮回422组合F2作为遗传群体进行育性相关基因的QTL定位,利用124对SSR标记构建了1张全长1 912.3 cM、平均图距为14.98 cM的饱和分子连锁图谱。利用Windows QTL Cartographer 2.5软件检测分析,在全基因组范围内检测到4个控制育性相关性状的QTLs位点,分别位于第2,3,5,7染色体上,单个QTL可解释4.5%～32.5%表型变异,其中位于第2染色体上RM5804与RM425之间的qpms-2贡献率为32.5%,第3染色体RM130与RM3405之间的qpms-3贡献率为16.1%。表明5021S的核不育性受2对隐性主基因控制,同时受微效基因调控。     

Mapping of Rice Fertility-Restoring Genes for ID-Type Cytoplasmic Male Sterility in a Restorer Line R68

An F2 population derived from the cross Zhong 9NR68 was used to map the fertility-restoring (Rf) gene for ID-type cytoplasmic male sterility (CMS).Two bulks (a fertile bulk and a sterile bulk) were constructed by pooling equal amount of ten highly fertile lines and ten highly sterile lines,respectively.Four hundred and thirteen pairs of simple sequence repeat (SSR) primers,which evenly distributed on 12 chromosomes of rice,were selected for analyzing polymorphisms between the parents and between the two bulks.The primer RM283 on chromosome 1 and the primers RM5756,RM258,RM6100 and RM171 on chromosome 10 were found to be polymorphic between the parents and between the two bulks.These five SSR markers were linked to fertility-restoring genes.A total of 82 excessive sterile lines were selected from Zhong 9NR68 F2 population to estimate the genetic distance between five SSR markers and fertility-restoring genes respectively.The results indicated that one Rf gene was linked to RM283 located on chromosome 1 at a distance of 6.7 cM,and the other Rfgene was mapped to the long arm of chromosome 10 flanked by RM258 and RM6100 at the distances of 8.0 cM and 2.4 cM,respectively.     

Genetic Analysis and Mapping of TWH Gene in Rice Twisted Hull Mutant

A mutant with twisted hulls was found in a breeding population of rice (Oryza sativa L.). The mutant shows less grain weight and inferior grain quality in addition to twisted hulls. Genetic analysis indicated that the phenotype of mutant was controlled by a single recessive gene (temporarily designated as TWH). To map the TWH gene, an F2 population was generated by crossing the twh mutant to R725, an indica rice variety with normal hulls. For bulked segregant analysis, the bulk of mutant plants was prepared by mixing equal amount of plant tissue from 10 twisted-hull plants and the bulk of normal plants was obtained by pooling equal amount tissue of 10 normal-hull plants. Two hundred and seven pairs of simple sequence repeat (SSR) primers, which are distributed on 12 rice chromosomes, were used for polymorphism analysis of the parents and the two bulks. The TWH locus was initially mapped close to the SSR marker RM526 on chromosome 2. Therefore, further mapping was performed using 50 pairs of SSR primers around the marker RM526. The TWH was delimited between the SSR markers RM14128 and RM208 on the long arm of chromosome 2 at the genetic distances of 1.4 cM and 2.7 cM, respectively. These results provide the foundation for further fine mapping, cloning and functional analysis of the TWH gene.     

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。     

水稻色素原基因C的精细定位

应用籼稻组合珍汕97B/密阳46的衍生材料,针对水稻第6染色体短臂色素原基因C的可能位置,筛选到在C基因周围区间呈不同基因型组合的7个剩余杂合体,收获种子建立F2∶3群体。在各个植株上,稃尖颜色和叶鞘颜色的表现完全相同。通过各个群体颜色表现与原剩余杂合体基因型的比较,将C基因定位于微卫星标记RM314与RM253之间。在该基础上,应用两个分离群体共1279个样本,经标记检测和连锁分析,进一步将C基因定位于RM111和RM253之间, 与RM111和RM253的遗传距离分别为0.7 cM和0.4 cM。最后,应用区间内的另外6个微卫星标记和1个源于C基因候选基因OsC1的标记,检测在RM111 C基因 RM253区间内发生了重组的22个个体,将C基因定位于一个大小为59.3 kb、涵盖C基因候选基因OsC1座位的区间中。     

Fine Mapping of C(Chromogen for Anthocyanin)Gene in Rice

Seven residual heterozygous lines(RHLs)displaying different genotypic compositions in the genomic region covering probable locations of C (Chromogen for anthocyanin)gene on the short arm of rice chromosome 6 were selected from the progenies of the indica cross Zhenshan 97B/Milyang 46.Seeds were harvested from each of the seven plants,and the resultant F2:3 populations were used for fine mapping of C gene.It was shown in the populations that the apiculus coloration matched to basal leaf sheath coloration in each plant.By relating the coloration performances of the populations with the genotypic compositions of the RHLS,the C locus was located between rice SSR markers RM314 and RM253.By using a total of 1279 F2:3 individuals from two populations showing coloration segregation.the C locus was then located between RM111 and RM253,with genetic distances of 0.7 cM to RM111 and 0.4 cM to RM253.Twenty-two recombinants found in the two populations were assayed with seven more markers located between RM111 and RM253,including six SSR markers and one marker for the C gene candidate,OsC1.The C locus Was delimited to a 59.3-kb region in which OsC1 was located.     

太湖流域粳稻地方品种黑壳子粳抗稻瘟病基因的分子定位

以广谱、高抗稻瘟病的太湖流域粳稻地方品种黑壳子粳与感病品种苏御糯杂交,产生F1、F2、F2∶3及F5∶6重组自交系群体,用日本稻瘟病鉴别菌系北1接种鉴定。黑壳子粳对北1的抗性是由1对显性主效基因控制的,定名为Pi hk1(t) 。根据不同杂交世代群体对北1的抗、感反应,结合SSR分子标记,将黑壳子粳中的Pi hk1(t) 基因定位在水稻第11染色体长臂末端,与RM7654和RM27381两个标记的遗传距离分别为0.9 cM和1.6 cM。     

Microsatellite-Aided Screening for Fertility Restoration Genes(Rf)Facilitates Hybrid Improvement

DNA markers enabled to determine the chromosomal locations of the two Rf genes(Rf3 and Rf4) in the wild-abortive cytoplasmic male sterility(WA-CMS) system. Four simple sequence repeats(SSRs) RM171, RM258, RM315 and RM443 were used to detect the allelic status with respect to the fertility restoration genes(Rf3 and Rf4) in 300 rice cultivars or breeding lines. The results revealed that out of 300 lines, 90 lines screened had Rf3, 65 lines had Rf4, and 45 lines had Rf3 and Rf4 alleles. Furthermore, 45 lines selected using SSR markers were mated with a CMS line(IR58025A) to analyze their restoring ability. Offspring of all the test lines except HHZ8-SAL9DT1-Y1, HHZ5-SAL9-Y3-1 and IDSA77 exhibited higher pollen and spikelet fertility( 80%), thus confirming they bear the Rf alleles. The hybrid offspring of ARH12-6-1-1-B-3-1, IR32307-10-3-2-1 and Sahel 329 had the highest pollen fertility(97.39%, 98.30% and 97.10%, respectively) and spikelet fertility(95.10%, 97.07% and 96.10%, respectively).     

Mapping a Novel Gene of Cold Tolerance at Booting Stage by Using Near-Isogenic Lines in japonica Rice

Genetic analysis showed that cold tolerance at booting stage of near-isogenic lines （NILs） of Kunmingxiaobaigu was controlled by a gene with large phenotypic variance. One hundred and sixty-four simple sequence repeats （SSR） distributed over 12 chromosomes were used to screen polymorphism between Towata （recurrent parent, RP） and near-isogenic line pool （NILP）, and two SSR markers at the long arm of chromosome 5 showed polymorphism in comparison with RP genome. Of the two markers, RM31 was found possibly linked with the cold tolerance gene at booting stage through one-way ANOVA. Twelve SSR markers around RM31 were then used to detect polymorphism between RP and NIL, and only RM7452 had polymorphism. The gene of cold tolerance at booting stage was further mapped on chromosome 5 between RM7452 and RM31 with genetic distances of 4.8 cM and 8.0 cM, respectively. This gene explained 10.50% of phenotypic variance and 5.10% of phenotypic variance of fully filled grains, and was tentatively designated as Ctb（t）.