小麦抗源Holdfast和Flinor抗条锈病主效、微效基因的遗传分析

【目的】Holdfast、Flinor是国际上已经报道在生产上具有持久抗条锈性表现的小麦品种，在成株期对中国条中29、30、31号小种表现出免疫或近免疫的抗性水平。【方法】本文采用常规杂交分析和潜育期变温处理方法，分别在常温（昼18℃/夜10℃）和高温（昼24℃/夜15℃）两种温域下，对其主效和微效抗条锈病基因进行遗传分析。【结果】品种Flinor中至少含有1显1隐2对主效和2对温敏微效抗条锈基因，Holdfast中至少含有2对显性主效和2对温敏微效抗条锈基因。主效基因均互补控制其抗条锈性,微效基因呈隐性，具累加效应，受高温诱导表达，控制中度抗性水平。【结论】Flinor和Holdfast均含有全生育期主效抗条锈病基因和对高温敏感的微效抗条锈基因，建议在抗病育种中加以有效利用，并提供了温敏微效抗条锈基因的快捷检测方法。     

京核系小麦抗锈性的研究

通过京核系小麦抗条锈性基因分析，初步证实太谷核不育小麦能集主效基因和微效基因共同作用的理论。     

太湖粳稻地方品种铁杆青抗稻瘟病的遗传研究

应用杂交分析法和累积分布曲线法，研究了太湖粳稻地方吕种铁杆青对中国稻瘟力优势小种ＸＧ１和太湖稻区近年出现频率较高的小种ＺＥ３的抗性遗传。结果表明：铁杆青对ＺＧ１小种的抗性是由１对显性基因控制的，对ＺＥ３小种的抗性除了１对显性基因外，可能有修饰基因或微效基因影响中抗类型的表达，并且两个抗病主基因为独立遗传；与３个已知抗基因的近等基因系的等位性测定表明，铁杆青所含的两个抗病基因与Ｐi－Ｋm、Ｐi－b是不等     

小麦抗条锈病微效抗性基因的开发研究

 利用对小麦条锈菌具有不同抗性强度的小麦品种作为亲本配成不同杂交组合,在分离世代中通过人工接种条锈病菌,将其不同反应型植株进行归类分组种植,再通过条锈病菌的接种鉴定,对各组继代分离个体继续进行抗性反应型归类分组种植.如此轮回数代,可从低世代感病类型个体中选择出抗性提高的植株.在无专化抗性基因控制的亲本品种间杂交所获得的中抗或中感材料是累积微效抗性基因的重要材料.在持续多代选育持久抗锈品种过程中,F₄及其以后的1～2代是累积微效抗性基因的关键世代.     

中国小麦条锈菌鉴别寄主南大2419抗条锈性遗传分析

南大2419(Mentana)是中国小麦条锈菌重要鉴别寄主之一。采用经典遗传分析与等位性分析相结合方法,通过分小种(菌系)鉴定,分析南大2419所含抗条锈病基因和遗传特点及其与已知基因的异同。结果发现:南大2419对Su-1和86036菌系的抗性正交由3对隐性互补基因控制,反交由2对隐性重叠或独立基因控制;对CY26小种抗性正交由2对隐性重叠或独立基因所控制,反交由2对隐性互补基因控制。正反交抗病遗传特点不同,可能与细胞质效应有关。等位性分析表明南大2419所含的3对主效基因与已知基因载体品系中的主效基因Yr7、Yr8、Yr9、Yr10、Yr17、Yr19、Yr22、Yr23、Yr27和YrSu不同,为未知基因,暂定名为YrMen1、YrMen2和YrMen3。     

小麦抗病性遗传的研究进展

对小麦抗病性的遗传研究进展进行了综述，小麦的抗病性遗传基础可分为两大类型。一类是主效基因控制的抗性；另一类是微效基因控制的抗性，主效基因对病原菌的抗性表现脆弱，在基因布局不合理时，容易被病原菌小种所克服，少数主效基因具有较好的持久性。微效基因单独存在时抗性作用很小，难以度量，对环境条件敏感，无明显的小种专化性，常表现为加性效应。小麦抗病性遗传的研究方法主要有：常规遗传分析法，基因的染色体定位法，基因推导法和遗传标记以及分子标记，丰富抗源和抗性品种的合理布局是保持品种持久性抗性的主要策略之一。     

水稻品种Acc8558抗白叶枯病的抗性基因定位

以高抗白叶枯病水稻品种Ａｃｃ８５５８和高感品种Ｈ３５９为亲本,采用单粒传方法建立一个重组自交系群体,利用该群体构建了一张包含２２５个分子标记的连锁图,１９９６、１９９７年对该群体连续２ａ进行了白叶枯病抗笥鉴定,并对白叶枯病抗性基因进行了定位分析,结果表明,白叶枯病的抗性由１铎主效基因控制,且存在一些微效的修饰基因,该主效基因位于第５号染色体的Ｒ８３０与Ｐ２２／Ｍ１７－４两标记之间,跟Ｒ８３０和Ｐ２     

澳大利亚小麦品种Sunco抗条锈病性状的遗传分析

澳大利亚小麦品种Sunco成株期对中国条锈病小种条中32(CY32)表现高抗-免疫,而小麦品种川育12则表现为高感。利用Sunco/川育12的双单倍体(DH)群体对Sunco进行抗条锈病遗传研究,结果表明,品种Sunco可能具有持久抗性,抗性是由一对主效基因和两对微效基因联合作用的结果;主效基因的抗性反应为抗-中抗(R-MR),微效基因单独存在作用不明显,但与主效基因结合起来会加强抗条锈病能力。同时对微效多基因的持久抗性利用作了初步探讨。     

数量性状的主效和微效基因检测方法研究

植物数量性状遗传由遗传效应较大的主效基因和效应较小的微效微基因控制。在杂交或回交后代群体中检测达到某一序列性状值的株数,通过极大似然检验可以确定控制该性状的遗传模型和各种遗传参数以及各种基因效应的大小。由于不同的遗传模型有着不同的遗传参数和不同的基因表现,需采用不同的迭代运算公式。为使众多迭代公式尽可能统一,该文提出了世代约束和分布约束的概念。     

大白菜核基因互作雄性不育性的研究

通过大白菜雄性不育两用系间不育株与可育株杂交,育成了4个稳定遗传的大白菜雄性不育系。该不育系雄蕊深度退化,小孢子发育停滞于单核早期,雌蕊具有正常的结籽能力。遗传分析表明,该不育性是由细胞核内两对主效基因及一些微效基因共同控制的。提出了大白菜细胞核主效基因显性抑制及微效基因修饰核基因互作雄性不育性遗传模式和应用模式。     

Genetic Analysis of Major and Minor Gene(s) Resistant to Stripe Rust in Important Resource Wheat Line Jinghe891-1

Inheritance of line Jinghe891-1 resistant to pathotype of Puccinia striiformis in two patterns of temperature (Normal: day 18℃/night 10℃, High: day 24℃/night 15℃ )was studied in this paper. The results showed that there were at least two pairs of dominant major genes and one pair of recessive minor genes in Jinghe 891-1. The two pairs of major genes that conferred resistance to CY31 were allelic or linked closely with resistance gene in Jubilejna Ⅱ , Kangyin655 and T. spelta Album. They were novel resistance genes and were inherited in a repeated or independent mode. The minor genes, which could modify the major genes,were sensitive to temperature and conferred resistance to all pathotypes of Puccinia striiformis in China. It is recommended that this line can be used as an important resource stock.     

小麦抗病基因同源序列(RGAs)的克隆与分析

RGA(抗性基因同源序列)法是克隆植物抗性基因的一种经济有效的方法,成为近年来的研究热点。本实验综合分析了拟南芥,西红柿,水稻,烟草等植物已克隆的抗性基因,并以这些抗性基因的NBS(核酸结合位点),LRR(富含亮氨酸重复),STK(丝氨酸/苏氨酸激酶)保守结构域设计并合成了几十对RGA引物,对小麦抗条锈病材料进行PCR扩增,获得以Xal-NBS为引物的R88RGA片段,经克隆和序列比对分析,发现该片段与逆境条件下植物抗病信号传导相关,与蛋白激酶同源性达到96%。此项研究对抗病机理的研究和基因的发掘有重要的指导意义。     

陇南小麦条锈病控制中抗病基因的布局

【研究目的】陇南地区为中国小麦条锈病核心疫源区,为了从源头治理,前人提出以抗病基因布局为核心内容的小麦条锈病控制的框架思路,但在实践中尚缺乏具体技术措施。【研究方法】通过对上世纪60年代以来陇南小麦品种的布局特点、抗源利用情况及陇南30年主要育成品种产量性状的分析。【研究结果】提出在陇南地区基因布局的数量约为6个,布局方式以若干品种为主体,采取"替补法"更换感病退化品种,并进行品种储备使基因布局进入动态替补状态。【结论】该技术为基因布局的完善与实践提供技术参考。     

Rht-B1b,Rht-D1b,Rht-B1c小麦矮秆基因及其互作对小麦农艺性状的影响

利用2套近等基因系,在人工模拟气候室,研究了不同Rht近等基因系营养性状的遗传差异.结果证明:Rht-B1b和Rht-D1b矮秆基因系不但具有很好的降秆作用,而且可以在生长前期形成较多的干物质和较坚硬的秆子,为后期籽粒产量的形成奠定基础;Rht-D1b半矮秆基因根系长度明显长于其它基因系,可能较其它基因系具有较强的耐旱能力;Rht-B1c基因系的分蘖数量及次生根或总根发生量多于其它基因系,无论苗高或株高均显著低于其它基因系,可在单纯的提高单株分蘖或次生根生长量及降秆为目的的育种中发挥一定作用.     

The Value of Different GA Insensitive Rht Dwarfing Genes in Winter Wheat Breeding

The value of different dwarfing genes in winter wheat breeding was studied using 6 nearisogenic lines carrying different Rht dwarfing genes over three years experiment.Results showed that both the Rhtl and Rht2 semi-dwarfing genes had significantly positive effects on kernel number and grain weight per spike, and had significantly negative effects on 1 000-grain weight comparing to the tall line(rht) and the Rht3 line.The Rht3 dwarfing gene had a significantly negative effect on kernel number per spike,and had positive effect on 1 000-grain weight. The combination of the Rht2 and Rht3 gene showed significantly negative effect on yield components. All of these 5 dwarfing or semidwarfing genotypes mentioned above had a significantly negative effect on plant height and no significant effect on the area of flag leaf, spikelets per spike and spike length.     

Anti-trxs和Bar基因共转化小麦后代植株的遗传及表型分析

经对基因枪转化小麦品种皖麦48获得的7株再生苗的PCR、PCR-Southern杂交和除草剂涂抹叶片检测,得到了4株转基因植株,证实了硫氧还蛋白反义基因(Anti-trxs)和抗除草剂Bar基因已经整合到小麦基因组中且能够正常表达。经对T1、T2植株分析表明:Anti-trxs、Bar基因能够稳定的遗传给后代,且普遍呈3∶1的分离,其遗传符合单基因控制的孟德尔遗传规律,部分株系表现1∶1的不正常分离(阳性个体较预期的少),推测这是由于雌或雄配子之一方丢失或外源基因的结构、排列等方面发生了变化的结果。转基因植株的农艺性状与对照相比,T0代有较大变异,但在T2代已得到了回复。     

反义Trx s基因对小麦种子萌发中α-淀粉酶的影响

为进一步明确转反义Trx s基因小麦抗穗发芽的生理机制,以转反义Trx s基因小麦为研究材料,采用电泳等生化技术分析了小麦种子萌发过程中α-淀粉酶活性及其同工酶的变化。实验结果表明,反义Trx s基因转入小麦后,明显降低了种子萌发过程中α-淀粉酶的活性。这种影响作用主要表现在三个方面:(1)影响酶蛋白的合成或降解速度;(2)影响酶存在的状态(抑制态和活性态);(3)影响淀粉酶由麦胚向胚乳的转运。     

Mapping of Fertility Restoring Gene for Aegilops kotschyi Cytoplasmic Male Sterility in Wheat Using SSR Markers

LK783 was found to be a good fertility restorer for K-type male sterility of wheat. Microsatellite markers were employed to map the major restoring gene in LK783. Maintainer and restorer DNA pools were established using the extreme sterile and fertile plants among (KJ5418A//911289/LK783)F1 population,respectively. Seventy-nine sets of SSR primers were screened for polymorphism between the two pools, 6 of which were found polymorphic. Linkage analysis showed that Xgwm11, Xgwm18 , Xgwm264a and Xgwm273were linked to the restoring gene in LK783, while Xgwm11, Xgwm18 and Xgwm273 were co-segregated. The distance between the Rf gene in LK783 and the three co-segregated markers was 6.54±4.37 cM, the distance between Rf gene and Xgwm264a was 5.71±4.10 cM. The four SSR markers were located on chromosome 1BS by amplifying the DNA of nulli-tetrasomics and ditelosomics of CS with the 4 sets of primers, indicating that the major restoring gene in LK783 was located on 1BS, but the relative location of the gene was different from Rfv1, allelism of the two genes should be further investigated. The breeding for new fertility restorer lines of K-type cytoplasmic male sterility in wheat would be facilitated by using the four polymorphic markers.     

STUDY ON D GENOME OF TRITICUMAESTIVUM SSP. YUNNANENSE KING

<正> Two accessions of Aegilops tauschii Cosson. one collected from the Middle East and the other from Henan Province of China. were crossed with Triticum aestivum ssp. yunnanense King. Chromosome pairings were analysed at metaphase Ⅰ. Meiotic configurations of the hybrids were 14.14Ⅰ+5.32 ring Ⅱ+1.52 rod Ⅱ for the Middle East Ae. tauschii x T. aestivum ssp. yunanense; 14.06Ⅰ+5.29 ring Ⅱ+1.69 rod Ⅱ for Henan Ae. tauschii x T. aestivum ssp. yunnanense. The frequencies of cells which had 7Ⅱ+14Ⅰconfiguration were 87.04％ and 97.05％ for the Middle East Ae. tanschii x T. aestivum ssp. yunnanense and Henan Ae. tauschii x T. asetivum ssp. yunnanense. respectively. The results indicated that D genome of T. aestivum ssp. yunnanense is unchanged compared with the D genome donor.