秋稻品种‘Dular’广亲和基因效应的RFLP分析

利用RFLP标记对秋稻品种Dular的三交（南京11／／Dular/2533）的F2群体与灿粳品种的测交F1进行了单株带鉴定,并对广亲和性的表达进行分析。结果表明：与第6染色体上标记RG213连锁的广亲和基因S5^n效应较大;不同位点广亲和基因具有明显的累加效应;位点内的互作导致了粳型配子的部分败育,同时还存在位点间的互作。     

水稻雄性不育新质源的研究──新型水稻细胞质雄性不育系马协A与野败型珍汕97A不育性的遗传学比较

采用套袋自交结实率和自然结实率为主,花粉育性和田间目测整株育性为辅的综合性状,判定新型细胞质雄性不育系马协Ａ以及它与明恢６３的杂种Ｆ１,Ｆ２和ＢＦ１的植株育性,并以野败型珍汕９７Ａ作对照,比较研究了其有性的遗传规律,结果表明,马协Ａ与珍汕９７Ａ不育性的遗传均由两对基因控制,但新型细胞质雄性不育系马协Ａ两对基因的作用方式与珍汕９７Ａ不同,前者Ｆ２群体的育性分离符合９：３：３：１的比例,ＢＦ１符合１：     

小麦的不同染色体组对G,S^v,D^2,M^u型细胞胞质“中国春”育性的影响

本文以Ｇ,Ｓ＾ｖ,Ｄ＾２,Ｍ＾ｕ型细胞质“中国春”小麦国母本与１１个不同染色体组类型小麦为父本进行杂交,观察当代的结实率,Ｆ１的育性与性状的变化,减数分裂行为,进一步探讨小玫的细胞质雄性不育与染色体组类型的关系。结果表明：当代结实率主要由父本染色体组类型决定,Ｆ１的育性表现十分复杂,同一父本与不同的异细胞质“中国春”杂交,有的表现可育,有的表现不育,细胞质有一定的影响。Ｆ１的性状,有的细胞质类型有     

有利基因和有利的基因互作能够提高籼粳杂种育性

利用一套籼粳交ＤＨ系与两份具有广亲和性的水稻光（温）敏核不育系测交,构建两个测交Ｆ１群体,同时用９２个多型性的ＲＦＬＰ标记分析了杂交亲本和另外３０个不同类型的籼、粳品种（对照组）的基因型。利用对照组籼或粳表型与分子标记的关联性,检测出４１个与籼粳分化高度相关的ＲＦＬＰ标记。结果表明,８７．８％的这种标记参与了对杂种优势显著或极显著的影响,表明在水稻的演化过程中,参与适应性进化的基因与控制经济产量的     

栽培稻杂种不育性的遗传研究：Ⅲ.不同类型品种F1花粉不育性的等位…

以台中６５等基因Ｆ１不育系为遗传测验种,测定了栽培稻４５个品种在３个Ｆ１不育基因座的基因型和等位基因的分化度,在Ｓ－Ｅ３基因座上,除Ｄｕｌａｒ带有Ｓ＾ｉ／Ｓ＾ｉ基因型外,其余被测品种均带有Ｓ＾ｉ／Ｓ＾ｉ基因型。在Ｓ－Ｅ２和Ｓ－Ｅ５基因座上,籼型品种带有高频率的Ｓ＾ｉ基因,而粳型品种带有高频率的Ｓ＾ｉ基因。Ｓ＾ｉ和Ｓ＾ｉ均具有不同的分化度,籼型品种携带的Ｓ＾ｉ基因和粳型品种携带的Ｓ＾ｉ基因具有较高的     

K型小麦细胞质雄性不育系育性恢复基因的RAPD和ISSR标记

利用RAPD和ISSR分子标记对K型小麦(Triticum aestivum L.)雄性不育恢复系LK783的主效恢复基因进行了标记定位.以K冀5418A//911289/LK783三交F1分离群体的极端不育株和极端可育株分别建立保持池和恢复池,利用418个RAPD和33个ISSR引物对两池间的多态性进行了研究.分析表明RAPD引物OPK18和ISSR引物UBC-845在两池间扩增出稳定的多态性差异,在分离群体上的验证结果表明LK783的育性恢复基因与两个引物的扩增位点有连锁关系,在染色体上位于两个引物的扩增位点之间,与OPK18450的遗传距离为(15.07±6.28)cM (centiMorgan),与UBC-845800的遗传距离为(8.20±4.85)cM.这两个引物可应用于对育性恢复基因的标记辅助选择.最后,利用中国春缺体-四体系和双端体系进一步将UBC-845800定位于1BS, 表明LK783的育性恢复基因也位于1BS.     

K型小麦细胞质雄性不育系育性恢复基因的RAPD和ISSR标记(英文)

利用RAPD和ISSR分子标记对K型小麦 (TriticumaestivumL .)雄性不育恢复系LK783的主效恢复基因进行了标记定位。以K冀 5 418A/ / 9112 89/LK783三交F1分离群体的极端不育株和极端可育株分别建立保持池和恢复池 ,利用 418个RAPD和 33个ISSR引物对两池间的多态性进行了研究。分析表明RAPD引物OPK18和ISSR引物UBC_845在两池间扩增出稳定的多态性差异 ,在分离群体上的验证结果表明LK783的育性恢复基因与两个引物的扩增位点有连锁关系 ,在染色体上位于两个引物的扩增位点之间 ,与OPK184 50 的遗传距离为 (15 .0 7± 6 .2 8)cM (cen tiMorgan) ,与UBC_845 80 0 的遗传距离为 (8.2 0± 4.85 )cM。这两个引物可应用于对育性恢复基因的标记辅助选择。最后 ,利用中国春缺体_四体系和双端体系进一步将UBC_845 80 0 定位于 1BS ,表明LK783的育性恢复基因也位于 1BS。     

短光低温不育水稻不育性的遗传观察

用若干常规品种与短光低温不育水稻宜ＤＩＳ配组,考察双亲及Ｆ１在自然低温影响前后的花粉育性,并于不育系稳定不育期间调查Ｆ２及Ｆ３的育性分离。结果表明：（１）低温是影响双亲及Ｆ１育性稳定性的重要生态因子;（２）Ｆ１的育性稳定性除与父本的育性稳定性有关外,可能尚与其他因素有关,这种育性稳定性表现是由可遗传因子决定的;（３）短光低温不育特性基本上符合２对独立主基因控制的遗传模式,但可能尚受到众多微效基因的     

水稻红莲型CMS育性恢复QTL分析

红莲型CMS是在我国杂交水稻生产中被广泛利用的雄性不育细胞质之一。为了同时定位红莲型CMS育性恢复主效和微效QTL,利用红莲型CMS不育系粤泰A(YTA)与“Lemont／特青”RIL群体测交,结合1张含有198个DNA分子标记的高密度遗传图谱,对测交F1群体的小穗育性和花粉育性进行复合区间作图。在对YTA的育性恢复性方面,该。RIL群体的2个亲本之间具有明显差异,特青的恢复性较强,其测交F1的小穗育性和花粉育性分别为72％和51％;而Lemont测交F1的小穗育性和花粉育性分别为32％和9％。复合区间作图定位到4个育性恢复QTL,分别位于水稻第1、2和10号染色体上,单个QTL的贡献率在5％～24％之间。其中,除1个QTL的增效基因来源于Lemont外,其余3个QTL的增效基因均来源于特青。效应最大的QTL为qRF-10-1,该QTL位于10号染色体RM258-C16标记区间,对小穗育性表型变异的贡献率为24％,对花粉育性的贡献率为17％,且该QTL被检测到的LOD值显著较高,因此是1个主效QTL,其增效基因来源于特青。除了主效QTLqRF-10-1外,其它3个QTL对性状的贡献率均在10％以下(5％～8％)。由此表明,该RIL群体对红莲型CMS的育性恢复由1个主效QTL控制,并受其它几个微效QTL的影响。该QTL定位结果与小穗育性在测交F1群体中呈连续的双峰分布的结果相一致。与主效QTL qRF-10-1紧密连锁的SSR标记为RM258,该主效QTL可作为分子标记辅助育种的操作目标之一,用于杂交稻分子育种中培育红莲型CMS的强恢复系。     

普通小麦1BL—1RS K,V型雄性不育体系育性恢复的研究

对１ＢＬ－１ＲＳ Ｋ,Ｖ型雄性不育系及其保持素与中国春及其第一部分同源群染色体全部６个缺－四体杂种Ｆ１的育性恢复进行了研究。结果表明：Ｋ型杂种的育笥恢复主要受１ＢＳ上Ｒｆｖ１基因的控制;而Ｖ杂种则受Ｒｆｖ１的１Ｄ染色上育性恢复基因的共同控制;在保持１Ｄ正常剂量的情况下,使恢复系中载有Ｒｆｖ１的１Ｂ染色体（片段）加倍,如１Ａ缺体－１Ｂ四体能使Ｋ,Ｖ型杂种1Ｆ的育性完全恢复。     

水稻广亲和性遗传的再研究

水稻广亲和基因的利用是克服亚种间杂种不育性的重要途径。但在广亲和性的遗传上不同研究者的结论不尽一致。以3种有广亲和品种参加的三交组合为研究材料,研究了品种Ketan Nangka的广亲和性遗传。结果表明水稻亚种杂交F1同时存在着雄性不育和雌性不育,但雄性不育对小穗育性的作用大小因组合而异;无论是在雄性不育位点还是雄性不育位点上,Ketan Nangka均具有相对应的中性基因（广亲和基因）;广亲和性的遗传特点与所用的籼粳测验品种间的杂种不育性密切相关;S－5位点的广亲和基因遗传符合单位点孢子体－配子体互作模型。     

Non-allelic interaction conditioning spikelet sterility in an F2 population of indica/japonica cross in rice

Significant segregation of spikelet fertility occurred in an F₂ population derived from a spikelet fertility-normal F₁ hybrid produced by a cross between Palawan, a japonica variety, and IR42, an indica variety. To identify factors controlling the fertility segregation, we used 104 RFLP markers covering all 12 rice chromosomes to investigate the association of spikelet fertility and marker segregation. We found that the segregation of two sets of gene pairs was significantly (P < 0.001) associated with fertility segregation. The first pair of genes was linked to RFLP marker RG778 on chromosome 12 and RFLP markers RG690/RG369 on chromosome 1. A significant reduction in fertility was observed when the plants were homozygote at RG778 with the indica allele as well as homozygote at RG690/RG369 with the japonica allele. The second pair of genes was linked to RG218 on chromosome 12 and RG650 on chromosome 7, respectively. The recombinant homozygote at these two loci showed a significant reduction on spikelet fertility. The non-allelic interaction effect was further modified by a gene linked to RG778, resulting in even lower fertility. The results of this study provides the first evidence of chromosomal localization of sporophytic sterility genes whose interaction can result in a reduction of spikelet fertility in the F₂ derived from fertility-normal F₁.     

Fine mapping of f5-Du, a gene conferring wide-compatibility for pollen fertility in inter-subspecific hybrids of rice (Oryza sativa L.)

Wide-compatibility varieties (WCVs), comprising a special class of rice germplasm, are able to produce fertile hybrids when crossed with both indica and japonica varieties. Dular, a landrace variety from India, has both a wide spectrum and high level of wide-compatibility when crossed with a range of indica and japonica varieties. In previous studies, an allele at the f5 locus from Dular (f5-Du) was identified as a neutral allele conferring wide-compatibility with a large effect on both pollen and spikelet fertility. Using a population of 1993 hybrid plants derived from a cross between ZS(f5-Du/f5-ZS) (F₁ of near isogenic line of Zhenshan 97 containing f5-Du) and Balilla (a japonica tester), f5-Du was genetically mapped to an interval of about 1.6 cM, with 0.8 cM from both SSR markers WFPM3 and WFPR1. Combined with bioinformatic analysis, a contig map was constructed for the f5 region, consisting of five bacterial artificial chromosome (BAC) or P1 artificial chromosome (PAC) clones and spanning approximately 437 kb in length. By assaying the recombinant events in the region with markers developed using the sequence information, the f5 locus was further narrowed down to a 70 kb fragment containing nine predicted genes. The result will be very useful for cloning this gene and marker-assisted transferring of the neutral allele in rice breeding programs.     

利用分子标记定位水稻野败型核质互作雄性不育恢复基因

以籼稻恢复系圭６３０与粳型广亲和品种０２４２８的Ｆ１代花药培养,获得８１个双单倍体（ＤＨ）,构建了有２３３个ＲＦＬＰ标记的分子图谱。用籼稻野败型不育系珍汕９７Ａ测定各ＤＨ系的恢复性,并将恢复性作为数量性状进行ＱＴＬ的区间作图分析,鉴别出８个基因座位,其中有２个基因座位,Ｒｆｉ－３和尾Ｒｆｉ－４,单个ＱＴＬ的基因贡献值分别是４９．６％和３５．４％,对育性恢复起主要作用,定为主效基因座位,位于第三和四染色体上,其它６个基因座位对育性恢复亦有一定的影响。表明野败型雄性不育恢复性是受主效基因和微效基因共同控制的性状。     

Molecularmarker diversity and hybrid sterility in indica-japonica rice crosses

 The partial sterility of hybrids between the indica and japonica rice subspecies of Asian cultivated rice is a serious constraint for utilizing inter-subspecific heterosis in hybrid rice breeding. In this study, we have investigated the relationship between molecular-marker polymorphism and indica-japonica hybrid fertility using a diallel set involving 20 rice accessions including 9 indica and 11 japonica varieties. Spikelet fertility of the resulting 190 F₁s and their parents was examined in a replicated field trial. Intra-subspecific hybrids showed much higher spikelet fertility than inter-subspecific hybrids except in crosses involving wide-compatibility varieties. The parents were surveyed for DNA polymorphism using 96 RFLP and ten SSR markers, which revealed extensive genetic differentiation between indica and japonica varieties. A large number of markers detected highly significant effects on hybrid fertility. The chromosomal locations for many of the positive markers coincided well with previously identified loci for hybrid sterility. The correlation between hybrid fertility and parental distance was low in both intra- and inter-subspecific crosses. The results suggest that the genetic basis of indica-japonica hybrid sterility is complex. It is the qualitative, rather than the quantitative, difference between the parents that determines the fertility of hybrids. Received: 3 January 1997/Accepted: 17 January 1997     

Two sequence alterations,a 136 bp InDel and an A/C polymorphic site,in the S5 locus are associated with spikelet fertility of indica-japonica hybrid in rice

The rice indica/japonica hybrid shows strong heterosis.However,such inter-subspecific hybrid can't be directly used in rice production due to its low spikelet fertility.The S5 locus was proved to be associated with fertility of indica/japonica hybrid and its S5n allele from wide-compatibility variety (WCV) is capable to overcome fertility barrier.In the present study,we reported the causal sites in the S5 locus responsible for compatibility of indica/japonica hybrid.Fine-mapping of the S5 locus using the 11...     

水稻杂种F1结实率与亲本程氏指数差异和同工酶遗传距离的关系及其预测研究

以4个籼粳测验种做母本按NCII(4×90)设计配置的360个杂交F1组合为材料,研究亲本的程氏指数差异(ID)、同工酶遗传距离(GD)与杂种F1结实率的关系.结果显示ID、GD与杂种F1结实率呈极显著负相关(r=-0.540,p＜0.01;r=-0.316,p＜0.01),但决定系数不高,分别是0.2916、0.0999.D、GD与F1结实率的相关性受父本和母本影响,其中对非广亲和品种测交F1结实率的预测效果较好,对广亲和品种及南京11的测交F1的预测则无效.因此,在利用ID和GD对水稻杂种F1结实率进行预测时,宜在一定的亲本类型之间进行,ID比GD的预测效果更好.     

Molecular basis underlying the S5-dependent reproductive isolation and compatibility of indica/japonica rice hybrids

The S5 locus regulates spikelet fertility of indica/japonica hybrid rice (Oryza sativa). There are three alleles at the S5 locus, including an indica allele (S5i), a japonica allele (S5j), and a wide-compatibility allele (S5n). This study analyzed the molecular basis for S5-dependent reproductive isolation and compatibility of indica/japonica rice hybrids. Three S5 alleles were expressed at extremely low levels, and only in the ovary. S5n was more similar to S5i in both RNA and protein expression profiles. The S5 locus was not essential for embryo sac development, although deleterious interactions between S5i and S5j resulted in reduced rates of spikelet fertility. The yeast two-hybrid system was used to test direct interactions between S5-encoded proteins. The results indicated that the S5i- and S5j-encoded eukaryotic aspartyl proteases formed both homodimers and heterodimers, whereas the S5n-encoded aspartyl protease was incapable of dimerization. Site-directed mutagenesis revealed that a single amino acid difference between S5i- and S5j-encoded aspartyl proteases (phenylalanine/leucine at residue 273) was primarily responsible for embryo sac abortion. The S5 locus may have promoted the subspeciation of indica and japonica, but it also enables gene flow between them.     

Two sequence alterations,a 136 bp InDel and an A/C polymorphic site,in the S5 locus are associated with spikelet fertility of indica-japonica hybrid in rice

The rice indica/japonica hybrid shows strong heterosis.However,such inter-subspecific hybrid can't be directly used in rice production due to its low spikelet fertility.The S5 locus was proved to be associated with fertility of indica/japonica hybrid and its S5n allele from wide-compatibility variety(WCV)is capable to overcome fertility barrier.In the present study,we reported the causal sites in the S5 locus responsible for compatibility of indica/japonica hybrid.Fine-mapping of the S5 locus using the 11 test-cross families pinpoints a candidate S5 locus encoding aspartic protease(Asp).Intragenic recombination within the Asp gene happened in a number of recombinants,resulting in chimeric S5j-S5n alleles.Just like S5n,the chimeric s5j-S5n allele displayed higher spikelet fertility when combined with the S5i allele.In the complementary test,however,the S5n allele from WCVs failed to enhance fertilities of the indica/japonica hybrids.Compared to both indica and japonica varieties.all nine WCVs from different resources are characterized with a 136 bp deletion in the Asp N-terminus.which probably renders the S5n allele non-functional.Furthermore,an A/C polymorphic site is detected 1,233 bp downstream of the Asp start codon.The heterozygous A/C site of the Asp gene in indica/japonica hybrid is believed to be the casual factorto causc partial sterility.The functional makers based on the two polymorphic sites will be broadly used in developing wide-compatibility rice varieties.