抗除草剂杂交稻的选育

通过杂交将抗除草剂Ｌｉｂｅｒｔｙ和ｂａｒ基因转移到恢复系,培育出３个除草剂恢复系测６４－Ｂ、明恢６３－Ｂ和特青－Ｂ。与不育系杂交,选配出３个抗除草剂三系杂交组合和２个抗除草剂两系杂交组合。抗除草剂组合能保持原组合的产量水平,苗期喷除草剂可淘汰假杂种。利用这项技术能解决两系、三系或化杀杂交稻在制种过程中出现的纯度问题。     

转bar基因水稻除草剂抗性遗传研究及其应用

试验用３个恢复系－测６４,明恢６３和特青作母本分别与３个抗除草剂转ｂａｒ基因水稻品种－Ｂｅｎｇａｌ－Ｈｕ１０,Ｃｙｐｒｅｓｓ ＰＢ－６和Ｇｕｌｆｍｏｎｔ杂交,对其后代（Ｆ１,Ｆ２和ＢＣ１）进行遗传分析表明,除草剂的抗性是受一对显性核基因控制,通过杂交可将这种基因转育到恢复系,配出抗除草剂杂交组合,应用这项技术可放宽对不育系完全雄性不育的严格要求,有利于优良不育系的培育及高产、优质,多抗新组合的选配     

不育系对杂交水稻F1主要性状的影响

三系杂交水稻F1是由不育系与恢复系配组而成的，而稳定的不育系又是由相应的理想的保持系回交转育而来，是保持系的同核异质体，其性状主要由核基因决定，而且保持系能结实各性状完整。因此，用不育系配组，对应的保持系为对比材料遗传效果是一致的。本试验的目的是为有效地选育保持系进而转育成不育系及配制强化新组合提供理论和实践的依据。材料和方法用野败型的珍汕97A、V20A、龙特甫A、福伊A、地谷A、黄菲A、宇菲人、天谷A、亩伊人等9个税稻不育系，与强优恢复系明恢63配制相应的9个杂交水稻组合：汕优63、威代63、特优63、福优63、…     

籼三系强优恢复系选育的有效途径──籼掺粳恢恢交低世代测鉴

强化恢复系是获得强优杂交稻新组合必不可少的条件，在不育系相同而恢复系不同的情况下，所配组合杂种优势的强弱、综合性状的好坏、产量水平的高低，都直接受到恢复系的制约。我国在税三系恢复系的选育方面，主要是采取测交筛选和杂交选育的方法，育成的恢复系中，以明恢63最为突出，用其配组育成的汕优63，近10余年来一直是我国舢型杂交稻的主栽组合，是我国应用面积最大、持续时间最长的杂交水稻组合。80年代以来，结合不育系的改良，以明恢63作恢复系与多个不育系配组，先后育成协代63、献改优63、D优63、红优63、特优63、马协优63、丝…     

形态优良的杂交水稻强优恢复系蓉恢906的选育

以株型优良的高产品种特青早作为理想株型的基因供体，与恢复系明恢63杂交，经连续多代选择，育成了集高产优良性状基因与恢复基因于一体的新恢复系蓉恢906。该恢复系配合力高、恢复力强、恢复谱广，株形、米质和抗性等特性都比明恢63有相应的提高和改良，用它所配组合表现综合性状好、杂种优势强。其中，冈优906、Ⅱ优906分别于1997年、1999年通过四川省品种审定委员会审定，迄今已在四川、江西、安徽、湖北等省累计推广13万多hm^2，并显示出较好的应用前景。     

抗瘟、丰产、优质的杂交稻新组合汕优多系1号

汕优多系1号是四川省内江市农科所用珍汕97A与该所新育成的恢复系多系1号配制而成的杂交水稻新组合。多系1号是利用广谱高抗稻瘟病亲本特特普与明恢63杂交、回交选育而成的，亲本组合为明恢63／特特普∥明恢63／／／明恢63。福建省寿宁县1994年从四川省秀山县种子公司引进，     

转溶菌酶基因水稻回交转育籼型杂交稻亲本

以抗稻瘟病的粳稻中花9号转溶菌酶基因材料D2 1 2与籼型杂交稻两优培九的恢复系9311及不育系培矮64S、汕优63的恢复系明恢63分别杂交和多代回交,进行外源溶菌酶基因的转育。对获得的转育回交后代B39311、B3MH63、B2PA64S和回交自交后代B2F29311、B2F2MH63、B1F2PA64S进行了PCR分析,表明外源基因在回交后代中呈1∶1分离,而在回交的自交后代中呈3∶1分离,证明外源溶菌酶基因是以单拷贝稳定传递给后代的。2003年和2004年对转育后代和测交组合进行了稻瘟病抗性调查,结果表明,转育后代抗性与轮回亲本相比、测交组合抗性与对应杂交稻组合相比都有了较大提高。随着转育回交世代的增加,抗性增强得越明显。研究表明通过回交转育方法将外源溶菌酶基因导入杂交稻亲本是选育抗稻瘟病杂交稻新组合的一条简便有效的途径。     

不同细胞质类型杂交水稻产量及农艺性状杂种优势分析

选用6种细胞质类型的10个雄性不育系（保持系）和10个恢复系,按不完全双列杂交配制100个组合,对不同细胞质类型杂交稻产量等8个农艺性状的杂种优势进行了分析。结果表明,同一性状不同组合和同一组合不同性状间,同一细胞质类型（恢复系）和不同恢复系（母细胞质类型）所配系列组合间的超亲优势和对照优势存在着较大差异;每穗总粒数、每穗实粒数和穗长具有较强的正向超亲优势和对照优势,结实率具有较强的对照优势,产量性状也具有一定的超亲优势和对照优势,其它性状超亲优势和对照优势都比较弱;6种细胞质类型中以冈型和D型所配系列组合超亲优势和对照优势最强;10个恢复系中以R 388所配系列组合的超亲优势最强,密阳46次之,明恢63所配系列组合的对照优势最强,R 478次之。在大多数性状上恢复系对组合的超亲优势和对照优势的影响大于细胞质类型。     

籼型恢复系绵恢2040的选育与应用

绵恢2040系西南科技大学水稻研究所用万恢228与多系I号杂交选育而成的具有粳稻亲缘的籼型恢复系，农艺、遗传性状稳定，具有恢复力和配合力强，较抗稻瘟病、品质较好、制种花粉量大、易获高产等特点；播抽期较明恢63短5d左右，温光反应特性与明恢63相似。所配组合B优840和C优2040已通过四川省农作物品种审定委员会审定。     

杂交稻新恢复系主要农艺性状的配合力分析

利用5个三系杂交稻不育系（金山2A、福伊A、京福5A、G201A、太香A）和5个杂交稻恢复系（22、制3、404、制6、明恢86）,通过不完全双列杂交配置了25个杂交稻组合,研究了这些新恢复系14个主要农艺性状的配合力。结果表明,14个主要农艺性状的一般配合力方差与特殊配合力方差均达显著或极显著差异水平,并且一般配合力方差明显大于特殊配合力方差,说明杂交稻主要农艺性状的遗传以加性效应为主。除有效穗和播始历期外,父本和母本对株高、穗长、穗颈长、剑叶长、剑叶宽、倒二叶、倒三叶、一次枝梗、二次枝梗、穗粒数、千粒重和结实率等12个农艺性状具有同等重要作用。杂交稻亲本的一般配合力和组合的特殊配合力是相互独立的,相同性状的亲本一般配合力和组合的特殊配合力效应不同,因此组合的特殊配合力是关键。制3、制6、404是一般配合力较好的恢复系,它们的杂种综合性状都比较好,是具有较好育种应用前景的恢复系。     

Recent Advances in Development of Herbicide Resistant Transgenic Hybrid Rice in China

In addition to weed control in direct seeding field of hybrid rice, herbicide resistance genes were used by Chinese scientists to increase and identify the purity of hybrid seeds, and to realize the mechanization of hybrid seed production. The elite restorer lines, such as Minghui 63, R752, T461, R402, D68 and E32 were transformed directly with herbicide resistance genes, in which D68 and E32 are restorer lines of two-line system and the others are of three-line system. Because almost all of important restorer lines are indica varieties and are recalcitrant in transformation, many herbicide resistant near-isogenic restorer lines were developed by sexual hybridization of indica and japonica varieties and backcross with indica restorer lines later, such as Ce 64, Minghui 63, Teqing, Milyang 46, R402 and 9311, in which 9311 is a restorer line of two-line system. The elite photoperiod-sensitive/thermo-sensitive genic male sterile lines, such as Pei'ai 64S, P88S, 4008S and 7001S, were transformed with herbicide resistance genes. A few herbicide resistant male sterile lines were developed through sexual hybridization and subsequently systemic selection, such as Bar1259S, Bar2172S, 05Z221A and 05Z227A. With the employment of herbicide resistant male sterile lines or herbicide resistant restorer lines, a few herbicide resistant hybrid rice combinations were developed, such as Xiang 125S/Bar 68-1 and Pei'ai 64S/Bar 9311. Based on herbicide resistance, the research was marching on to investigate the parental lines of hybrid rice with insect resistance, drought tolerance, etc.     

Improvement of bacterial blight resistance of hybrid rice in China using the Xa23 gene derived from wild rice (Oryza rufipogon)

A novel bacterial blight (BB) resistance gene, Xa23, identified from Oryza rufipogon was introgressed into three popular restorer lines (Minghui63, YR293 and Y1671) for wild abortive cytoplasmic male sterility by marker-assisted backcross breeding approach in combination with artificial inoculation and stringent phenotypic selections. The three derived BB resistant restorer lines (Minghui63-Xa23, YR293-Xa23 and Y1671-Xa23) and their hybrid combinations with Zhenshan97A (Shanyou63-Xa23), NongfengA (Fengyou293-Xa23) and Zhong9A (Zhongyou1671-Xa23) demonstrated similar BB resistance spectrum as the donor parent, CBB23 (B). The newly developed BB resistant restorers and their derived hybrids were identical to their respective original versions for agronomic traits especially under disease free condition. However, under severe disease condition, the three BB resistant restorer lines exhibited significantly higher grain weight and spikelet fertility as compared to the respective original restorer lines thus further resulting in BB resistant hybrids with significantly higher grain yields than their respective popular original hybrids. The results indicated that the Xa23 gene could completely express its dominant broad spectrum resistance in different backgrounds of both restorer and male sterile lines across different growth stages, suggesting its immense breeding value in BB resistance improvement for hybrid rice. Moreover, a reasonable utilization and deployment of Xa23 gene for efficient control of BB disease in hybrid rice production was recommended.     

转基因抗虫性水稻恢复系选育及特性分析

将优质抗稻瘟病水稻恢复系成恢177与转基因水稻Bt明恢63杂交并回交1次,采用PCR分析、试纸条检测、室内和田间人工接虫鉴定抗虫性,并结合系谱法选择农艺性状,病圃接种鉴定稻瘟病抗性,育成具转基因抗虫性的水稻新恢复系Bt5198。采用离体茎秆法接种二化螟卵块,新恢复系Bt5198和Bt明恢63的幼虫死亡率均为100%。在田间人工接虫条件下,该恢复系对二化螟和三化螟均表现高抗,与4个不育系配制的杂种F1仍保持良好的抗虫性,且杂种优势明显。两年稻瘟病抗性鉴定结果表明,新恢复系Bt5198的叶瘟和颈瘟抗性水平与成恢177相当,明显优于Bt明恢63。Bt5198的种子发芽率和花粉量与成恢177相当,Bt基因导入水稻恢复系不会对种子生活力和制种产量造成显著影响。在无选择标记基因的转基因后代中,结合利用试纸条检测和室内、田间人工接虫鉴定是筛选Bt基因抗虫性的有效方法。     

Transfer of Lysozyme Gene into indica Parents of Hybrid Rice by Backcrossing

Rice blast (Pyricularia oryzae Cavara), one of the major fungal diseases in rice fields all over the world, is induced by the ascomycetous fungus Magnaporthe grisea (Hebert) Barr [Anamorph: Pyricularia grisea (Cooke) Sacc.] [1]. According to the statistic…     

Breeding and Characterization of a New Rice Restorer Line Containing Bt Gene

Bt5198, a new rice restorer line containing Bt gene, was developed from the cross and backcross of the elite restorer line Chenghui 177 with Bt Minghui 63, a transgenic Bt restorer line. The inbred lines were evaluated using PCR amplification, test paper evaluation, insect resistance evaluation in both the laboratory and paddy fields, nursery evaluation of rice blast resistance and pedigree selection of agronomic traits. Larval mortalities on Bt5198 and Bt Minghui 63 were 100% when rice culms were inoculated with the eggs of the striped stem borer (SSB) in the laboratory. Bt5198 was highly resistant against SSB and the yellow stem borer (YSB) under field conditions. The F₁ hybrids derived from Bt5198 and four cytoplasmic male sterile (CMS) lines were also highly resistant to SSB and YSB and had a significant heterosis. Two-year evaluation of rice blast resistance confirmed that the resistance levels of Bt5198 to leaf blast and neck blast were similar to those of Chenghui 177 and significantly better than those of Bt Minghui 63. Seed germination ability and pollen yield of Bt5198 were similar with Chenghui 177, suggesting that the introduction of the Bt gene into the new restorer line had no significant effects on seed vitality or the yield of seed production. To identify the presence of the Bt gene, it was effective to combine test paper examination with the evaluation of insect-resistance, both in the laboratory and under field conditions.     

野生稻高产QTL的分子标记辅助育种进展

1995年中国国家杂交水稻工程技术研究中心与美国康奈尔大学合作,在马来西亚普通野生稻中鉴定出两个主效高产QTLyld1.1和yld2.1.随后将野生稻高产QTL导入优良晚稻恢复系测64-7及中稻恢复系9311和明恢63中,采用分子标记辅助选择与田间选择相结合,育成了Q611等携带野生稻高产QTL yld1.1和yld2.1的新恢复系.经测交鉴定,Q611所配组合表现出强大的产量优势,说明野生稻高产QTL具有显著的增产效应和重要的育种价值,同时也表明采用分子标记辅助选择方法对数量性状进行遗传改良同样具有明显的效果.