大白菜显性不育基因向白菜型油菜上转育的遗传研究

利用大白菜的显性核不育基因向白菜型油菜上转育,成功地育成了白菜油菜３种不育系。其配合力测定的总趋势,甲型不育〉全不育〉乙型不育,经遗传分析,选育,找到了上位显性核互作恢复基因（Ｍｓ）,它对核不育基因（Ｓｐ）具有上位恢复作用,育性是２对显性核不育基因（Ｓｐ）和上位显性核互作恢复基因（Ｍｓ）控制的。并弄清了其相应的遗传模式。     

大白菜显性核不育基因向白菜型油菜上转育的遗传研究

利用大白菜的显性核不育基因向白菜型油菜上转育,成功地育成了白菜型油菜３种不育系。其配合力测定的总趋势：甲型不育＞全不育＞乙型不育。经遗传分析、选育,找到了上位显性核互作恢复基因（Ｍｓ）,它对核不育基因（Ｓｐ）具有上位恢复作用。育性是由２对显性核不育基因（Ｓｐ－）和上位显性核互作恢复基因（Ｍｓ－）控制的。并弄清了其相应遗传模式。     

小麦显性核不育基因的遗传效应 Genetic Effects of a Dominant Male Sterile Gene on F1 in Common Wheat

采用NCII设计研究显性核不育基因在40个杂种F1代的遗传效应。结果表明，显性核不育基因对F1代形态性状影响不大，而对产量、产量性状及品质性状的影响较大。F1形态性状主要表现加性效应，且不育株和可育株趋势一致；可育株单株产量及大部分产量性状表现显性效应，百粒重、每小穗粒数表现加性效应，而不育株这些性状的加、显性效应起作用。F1两种育性植株蛋白质含量的遗传以加性效应为主、蛋白质产量以显性效应为主，籽粒饱满度则是可育株以加性效应为主，不育株以显性效应为主。显性核不育基因在F1代有明显的母性效应，且在这种基因的细胞质基础上核质互作也很重要。     

籼型光敏核不育水稻育性可转换性的基因定位和基因互作研究

本研究以来源于农垦58S的灿型光敏核不育系培矮64S（短日条件下育性难转换）和8902S（短日条件下育性蝗转换）及其F1,F2群体为材料,通过短日不同光温和不同生态条件4种处理,利用RFLP分子标记研究了影响光敏偿育水稻在短日条件下的育性可转换性的遗传,基因定位和基因互作,主要结果表明：影响光敏不育水稻的育性可转换性表现为微效基因的作用,定位了7个控制光敏核不育水稻的育性可转换性QTL,即S2,S3a,S3b,S5,S8和S10,揭示了基因互作真实存在于光敏核不育水稻中,基因互作形式和互作类型对光敏核不育水稻的育性可转换性的影响表现多种多样,不同类型的基因互作所解释的遗传变异处于2．15％－10．07％之间。     

是“基因互作”，还是“复等位”？— 兼与马尚耀先生讨论

对“Ch型”谷子显性核不育材料遗传机制的研究表明，其不育性受两对显性连锁基因控制，属“基因互作”的一种形式。所谓“复等位”的观点，我们认为是错误的。     

籼型光敏核不育水稻育性可转换性的基因定位和基因互作研究

本研究以来源于农垦58S的籼型光敏核不育系培矮64S(短日条件下育性难转换)和8902S(短日条件下育性易转换)及其F１、F２群体为材料,通过短日不同光温和不同生态条件4种处理,利用RFLP分子标记研究了影响光敏核不育水稻在短日条件下的育性可转换性的遗传、基因定位和基因互作,主要结果表明：影响光敏核不育水稻的育性可转换性表现为微效基因的作用,定位了7个控制光敏核不育水稻的育性可转换性QTL,即S2、S3a、S3b、S5、S8和S10。揭示了基因互作真实存在于光敏核不育水稻中,基因互作形式和互作类型对光敏核不育水稻的育性可转换性的影响表现多种多样,不同类型的基因互作所解释的遗传变异处于2.15%～10.07%之间。     

水稻“三明”显性核不育基因的定位

"三明显性核不育水稻"突变体是由福建省三明市农业科学研究所于2001年在杂交组合"SE21S/Basmati370"的F2代群体中发现的。其不育性受1个显性基因控制(将该基因命名为SMS)。经过多代回交,该显性不育基因已导入籼稻品种佳福占的遗传背景中(将该不育材料称为佳不育)。为了定位SMS,文章将佳不育与粳稻品种日本晴杂交,并将F1与佳福占测交,构建了一个作图群体。利用SSR和INDEL标记,通过混合分离分析和连锁分析,将SMS定位于第8号染色体上两个INDEL标记ZM30和ZM9之间,约99 kb的区间内。该结果为克隆SMS奠定了基础。     

水稻紫色柱头的遗传分析与基因定位

rdh是四川农业大学水稻研究所通过组织培养和连续自交得到的一个具有红色籽粒和紫色柱头,遗传上稳定的籼稻材料。抽穗期在rdh与3个无色柱头品种蜀恢527、蜀恢368和蜀恢168之间分别做正反交,结果显示F1群体在柱头颜色上正反交之间没有明显区别,全部是紫色的。F2群体发生分离成为两组,一组具有紫色柱头,另一组具有无色柱头。每一个F2群体的紫色柱头对无色柱头均适合3：1的比例,表明rdh紫色柱头性状的遗传是由一对显性核基因控制的。组合rdh／蜀恢527 F2分离群体中40个具有紫色柱头的显性单株和284个具有无色柱头的隐性单株构成定位群体。从两个亲本rdh和蜀恢527提取的基因组DNA,用涵盖水稻整个基因组的252对微卫星标记作引物扩增片段。结果发现有78对微卫星标记在两亲本之间具有多态性。然后用这78对标记作引物,扩增亲本、F1、F2显性单株和F2隐性单株、,结果显示位于水稻第6染色体的RM276、RM253以及RM111与rdh紫色柱头基因有连锁关系。再用RM276、RM253以及RM111作引物扩增剩余的全部具有无色柱头的隐性单株。结果表明：在RM276的扩增产物中,有20个单交换和2个双交换;在RM253中有2个单交换：在RM111中有3个单交换。因此,rdh紫色柱头基因被定位于水稻第6染色体。根据公式P=（h＋2b）／2n,计算得到微卫星标记RM276,RM253和RM111与rdh紫色柱头基因的遗传距离分别是4．2cM、0．35cM以及0．53cM。根据已经发表的RM276、RM253和RM111在第6染色体上的位置以及计算得到的rdh与RM276、RM253和RM111之间的遗传距离,构建了部分连锁图谱,并暂时将这个紫色柱头基因命名为Ps-4。     

植物基因互作型显性核不育材料的新假说

植物基因互作型显性核不育材料的新假说刘秉华（中国农业科学院作物育种栽培研究所北京１０００８１）植物雄性不育是一种常见的自然现象,有的受遗传基因控制,有的则由于外界环境条件影响所致。显性基因控制的雄性不育称为显性核不育。在通常情况下,显性核不育材料的异...     

利用SSR标记定位明恢63的2对恢复基因

选取珍汕97A和明恢63杂交组合的F2高可育和高不育单株构建基因池,利用302对SSR引物对其进行了多态性分析。结果表明,位于第1染色体上的RM1和位于第10染色体上的RM258,RM304在亲本,基因池间表现多态性,用F2单株验证证明它们与野败型恢复基因连锁,完全不育株分析表明,与恢复基因间的遗传距离分别为1.9,2.9和0.0cM,野败型,红莲型,BT型3种不育胞质恢复基因在第10染色体上可能为同一基因或家族成员。     

一个水稻显性高秆突变体的遗传分析和基因定位

从水稻(Oryza sativa L.)的两个半矮秆籼稻品种6442S-7和蜀恢881杂交F2代群体中发现一个高秆突变体D111,其株高和秆长分别比亲本蜀恢881增加63.0%和87.0%.用205个微卫星标记分析D¨1及其原始亲本6442S-7和蜀恢881之间的基因组DNA多态性,结果未发现D111具有2个原始亲本都没有的新带型,证明D1¨的确是6442S-7和蜀恢881的杂交后代发生基因突变产生的.将D111分别与蜀恢881、蜀恢527、明恢63、9311、IR68、G46B等6个半矮秆品种和高秆对照品种南京6号杂交,分析F1和F2代株高的遗传行为,结果表明D1¨的高秆性状由一对显性基因控制,且该基因与南京6号的高秆基因紧密连锁或等位.以蜀恢527/D111 F2群体为定位群体,运用微卫星标记将D111显性高秆突变基因定位于水稻第一染色体长臂,与RM212、RM302和RM472的遗传距离分别是27.7 cM、25.5 cM和6.0 cM,该基因暂命名为LC(t).认为D111是首例从半矮秆品种自然突变产生的水稻显性高秆突变体,LC(t)为首次定位的水稻显性高秆突变基因.此外,将上述基因定位结果与Causse等(1994)和Temnykh等(2000,2001)发表的水稻分子连锁图谱进行比较,发现LC(t)基因恰巧位于与水稻"绿色革命基因"sd1相同或十分相近的染色体区域,因此,还就LC(t)基因与sd1基因之间的可能关系进行了讨论.     

一个水稻显性高秆突变体的遗传分析和基因定位

从水稻(Oryza sativa L.)的两个半矮秆籼稻品种6442S-7和蜀恢881杂交F2代群体中发现一个高秆突变体D111,其株高和秆长分别比亲本蜀恢881增加63.0%和87.0%。用205个微卫星标记分析D111及其原始亲本6442S-7和蜀恢881之间的基因组DNA多态性,结果未发现D111具有2个原始亲本都没有的新带型,证明D111的确是6442S-7和蜀恢881的杂交后代发生基因突变产生的。将D111分别与蜀恢881、蜀恢527、明恢63、9311、IR68、G46B等6个半矮秆品种和高秆对照品种南京6号杂交,分析F1和F2代株高的遗传行为,结果表明D111的高秆性状由一对显性基因控制,且该基因与南京6号的高秆基因紧密连锁或等位。以蜀恢527/D111 F2群体为定位群体,运用微卫星标记将D111显性高秆突变基因定位于水稻第一染色体长臂,与RM212、RM302和RM472的遗传距离分别是27.7 cM、25.5 cM和6.0 cM,该基因暂命名为LC(t)。认为D111是首例从半矮秆品种自然突变产生的水稻显性高秆突变体,LC(t)为首次定位的水稻显性高秆突变基因。此外,将上述基因定位结果与Causse等(1994)和Temnykh等(2000; 2001)发表的水稻分子连锁图谱进行比较,发现LC(t)基因恰巧位于与水稻“绿色革命基因”sd1相同或十分相近的染色体区域,因此,还就LC(t)基因与sd1基因之间的可能关系进行了讨论。     

Aanlysis of short photo-periodic sensitive genic male sterility and molecular mapping of rpms3(t) gene in rice (Oryza sativa L.) using SSR markers

A research was conducted on the pollen fertility of rice sterile lines D52S and D38S responsive to photoperiod during the sensitive stage under natural and controlled conditions. Bulk segregant analysis (BSA) and recessive class approach were applied to identify DNA markers that co-segregate with gene conferring male-sterility in D52S mutant rice. The results showed that in day-light higher or equal to 14.00 h, D52S and D38S rice pollen were fertile; however, they were sterile when day-length was less than 14.00 h. They were therefore considered to be short photo-periodic sensitive genic male sterile lines(Short PGMS lines). Under short day-light conditions, the pollen fertility segregation of F₂ populations from crosses between D52S/Shuhui527 and D52S/Gui99showed 3:1 ratio of fertile to sterile plants suggestingthat male sterility in D52S was controlled by one recessive gene. Two markers RM244 and RM216 located on chromosome number 10 co-segregated completely with the rpms locus. The locus was mapped to the interval between SSR markers RM2571 (6.6 cM) and RM244 (4.6 cM).     

Genetic Analysis and Gene Mapping of Purple Stigma in Rice

A new double-haploid (rdh) rice plant with purple stigma and red seeds was discovered by tissue culture. Genetic analysis suggested that the trait of rdh purple stigma was controlled by a pair of dominant gene. Polymorphic analysis of microsatellite markers demonstrated that the purple stigma gene of rdh was located on rice chromosome 6 at 4.2 cM, 0.35 cM and 0.53 cM from microsatellite markers RM276, RM253 and RM111, respectively. It was believed that the purple stigma gene of rdh was the first mapped purple stigma gene on rice chromosome 6. This purple stigma gene was designated tentatively as Ps-4.     

Genetic analysis of temperature-sensitive male sterilty in rice

The present study of genetic analysis is an attempt to precisely characterize diverse temperature-sensitive genic male-sterile (TGMS) lines so as to explore the possibilities of utilizing the most promising in large-scale hybrid seed production. Genetical studies revealed that the TGMS segregants derived from crosses involving TGMS lines ID24 and SA2 expressed differential fertility levels at low-temperature conditions. A majority of these progenies expressed transgressive segregation towards either sterility of fertility, causing instability of sterility and low reversibilty of fertility which may be due to large numbers of single-locus QTLs and their epistatic interactions. We identified two putative genes imparting temperature-sensitive male sterility after observing crosses involving diverse TGMS sources. To identify suitable molecular markers closely linked to the trait we used RAPD, AFLP and microsatellites which generated polymorphism through bulked segregant analysis. AFLP analysis using a smaller genome kit resulted in enormous polymorphism, out of which the combination EAA/MCAG amplified a 330-bp fragment, which closely segregated with the gene at a distance of 5.3 cM. This fragment was eluted for cloning and from the sequence a STS primer (TS200) was developed which produced a dominant polymorphism specific to TGMS. The microsatellite RM257, located earlier on chromosome 9, was linked with the TGMS trait in SA2 at a distance of 6.2 cM. RM257 produced a codominant polymorphism with 145-bp (sterile) and 132-bp (fertile) products. Both individually and collectively, the markers TS200 and RM257 located on either side of the TGMS locus are very useful for marker-assisted selection. Received: 10 April 1999 / Accepted: 29 July 1999     

Genetic characterization and fine mapping of a novel thermo-sensitive genic male-sterile gene tms6 in rice (Oryza sativa L.)

The application of genetic male sterility in hybrid rice production has great potential to revolutionize hybrid seed production methodology. The two-line breeding system by using thermo-sensitive genic male sterility (TGMS) has been discovered and successfully developed as a breeding strategy in rice. One TGMS gene was investigated by a spontaneous rice mutant line, Sokcho-MS, originated from a Korean japonica variety. It was shown that Sokcho-MS is completely sterile at a temperature higher than 27°C and/or lower than 25°C during the development of spikelets, but fertile at the temperature ranging from 25 to 27°C regardless of the levels of day-length. Genetic analysis and molecular mapping based on SSR, STS and EST markers revealed that a single recessive gene locus involved the control of genic male sterility in Sokcho-MS. By using an F₂ mapping population derived from a cross between Sokcho-MS and a fertile indica variety Neda, the new TGMS gene, designated as tms6, was mapped primarily to the long arm of chromosome 5 of Oryza sativa at the interval between markers E60663 (2.0 cM) and RM440 (5.8 cM). Subsequently, tms6 was fine mapped to the interval between markers RM3351 (0.1 cM) and E60663 (1.9 cM). As tms6 appeared to be independent of other mapped TGMS genes in rice, the genetic basis of Sokcho-MS was further discussed.     

Fine mapping and candidate gene analysis of <Emphasis Type="Italic">ptgms2-1</Emphasis>, the photoperiod-thermo-sensitive genic male sterile gene in rice (<Emphasis Type="Italic">Oryza sativa</Emphasis> L.)

Photoperiod-thermo-sensitive genic male sterile (PTGMS) rice exhibits a number of desirable traits for hybrid rice production. The cloning genes responsible for PTGMS and those elucidating male sterility mechanisms and reversibility to fertility would be of great significance to provide a foundation to develop new male sterile lines. Guangzhan63S, a PTGMS line, is one of the most widely used indica two-line hybrid rice breeding systems in China. In this study, genetic analysis based on F₂ and BC₁F₂ populations derived from a cross between Guangzhan63S and 1587, determined a single recessive gene controls male sterility in Guangzhan63S. Molecular marker techniques combined with bulked-segregant analysis (BSA) were used and located the target gene (named ptgms2-1) between two SSR markers RM12521 and RM12823. Fine mapping of the ptgms2-1 locus was conducted with 45 new Insertion–Deletion (InDel) markers developed between the RM12521 and RM12823 region, using 634 sterile individuals from F₂ and BC₁F₂ populations. Ptgms2-1 was further mapped to a 50.4 kb DNA fragment between two InDel markers, S2-40 and S2-44, with genetic distances of 0.08 and 0.16 cM, respectively, which cosegregated with S2-43 located on the AP004039 BAC clone. Ten genes were identified in this region based on annotation results from the RiceGAAS system. A nuclear ribonuclease Z gene was identified as the candidate for the ptgms2-1 gene. This result will facilitate cloning the ptgms2-1 gene. The tightly linked markers for the ptgms2-1 gene locus will further provide a useful tool for marker-assisted selection of this gene in rice breeding programs.     

Genetic Analysis and Molecular Tagging on a Novel Excessive Tillering Mutant in Rice

A rice (Oryza sativa L.) mutant with an excessive tiller number, designated ext-M1B, was found in the F₂ progenies generated from the cross between M1B and GMS-1 (a genetic male sterile), whose number of tillers was 121. The excessive tillering mutant also resulted in significant changes in plant height, flag leaf, stem, filled grains per panicle, and productive panicles per plant. The inbreeding progenies of ext-M1B exhibited the same mutant phenotype. The crosses from ext-M1B/M1B, M1B/ext-M1B, 2480B/ext-M1B, D62B/ext-M1B, G46B/ext-M1B, and G683B/ext-M1B expressed normal tillering in F₁, and segregated into two different phenotypes of normal tillering type and excessive tillering type in a ratio of 3:1 in F₂. Inheritance analysis indicated that the excessive tillering character was controlled by a single recessive nucleic gene. By BSA (bulked segregants analysis) and microsatellite makers with the F₂ population of 2480B/ext-M1B as the mapping population, RM197, RM584, and RM225, all of which were located on the short arm of rice chromosome 6, were identified to be linked with the excessive tillering gene with genetic distance of 3.8 cM, 5.1 cM, and 5.2 cM, respectively. This gene is probably a new excessive tillering gene in rice and is designated tentatively ext-M1B (t).