齐319携带的南方玉米锈病抗性基因的遗传初析

我国选育的优良玉米自交系齐319高抗南方玉米锈病。通过用病原菌接种齐319分别与5个不同感病自交系的杂交,回交4个世代的P1,P2,F1,F2,BC1F110个分离群体和抗病感病参数的调查结果表明：F1整齐一致,表现抗病;F2和BC1F1抗感分离,经x^2－检验分别符合3：1和1：1的分离比例。据此,齐319携带的南方玉米锈病抗性基因是由显性单基因所控制。     

南方玉米锈病抗病基因的定位及不同遗传背景对基因标记的比较分析

玉米自交系齐319高抗南方玉米锈病。利用SSR标记技术和BSA分析对齐319抗南方玉米锈病基因进行了标记分析,结果表明SSR标记phi041和phi118与齐319抗南方锈病基因连锁,其遗传距离分别为7.69cM和8.55cM。因此南方玉米锈病抗病基因定位于玉米10号染色体短臂上。本研究进行的抗病基因标记,选择使用了两个杂交组合的3个分离群体,标记结果显示同一杂交组合的不同分离群体其标记结果是一致的,而不同组分分离群体的标记结果有显著差异,这可能与基因的遗传背景相关。因此,在进行基因标记分析时,选择合适的分离群体是至关重要的。     

玉米抗南方锈病基因的QTL定位

为发掘新的抗南方锈病基因资源,本研究以感病自交系黄早四为母本、抗病自交系W456为父本,构建F2群体并开展抗病基因定位研究。采用人工接种鉴定的方法对两个亲本、F1、F2群体及对照材料进行表型鉴定和遗传分析。利用均匀覆盖10条染色体的200个SSR标记,分析240个F2单株的基因型并构建含有200个SSR位点的遗传连锁图,连锁图总长度3331 cM,标记间平均距离16.6 cM。使用QTL IciMapping V4.1软件中的完备区间作图法对抗病QTL进行分析,共检测到6个控制南方锈病的QTL:qSCR3、qSCR7、qSCR8-1、qSCR8-2、qSCR9和qSCR10,邻近标记分别为umc2105和umc1729、umc1066和bnlg2271、umc1904和umc1984、umc1984和bnlg1651、umc1957和bnlg1401、umc2034和umc1291,分别位于3、7、8、9和10号染色体上,其中8号染色体上有两个位点,标记区间长度在5～19 cM之间。单个QTL的表型贡献率在2.61%～24.19%之间,可以解释表型总变异的62.3%,其中3个QTL贡献率大于10%,位于10号染色体上的qSCR10贡献率最大,可解释表型变异的24.19%。通过对目标区间标记加密,将该位点的定位区间进一步缩小到2.51 cM内,与两侧标记的距离分别是2.15 cM和0.36 cM。初步定位得到10号染色体上存在抗南方锈病的主效QTL,可为抗病品种的培育提供参考。     

辣椒株高遗传分析

以辣椒矮秆自交系B9431（P1）和高秆自交系‘吉林长椒’（P2）为双亲,构建P1、F1、P1、B1、B2和F2 6个家系世代群体,应用植物数量性状主基因＋多基因混合遗传模型对该6个世代群体株高进行多世代联合分析,结果显示：株高遗传符合1对主基因＋多基因遗传模型,高秆对矮秆表现为不完全显性,F1代株高的势能比值为0．39,显性程度为0．91。B1、B2和F2群体主基因遗传率分别为20．35％、17．20％和35．29％,多基因遗传率分别为5．08％、19．75％和0;主基因效应表现为负向加性效应,其值为-6．43,显性效应为0;多基因加性效应值和显性效应值分别为-8．89和9．77。研究还表明,主基因与多基因间的基因效应存在一定差异,主基因加性效应值相当于多基因加性效应值的72．33％,主基因无显性效应,显性效应是由多基因控制遗传。     

雌雄同株黄瓜单性结实性主基因+多基因混合遗传分析

以雌雄同株黄瓜强单性结实自交系'6457'和非单性结实自交系'6426'为亲本,建立了5世代联合群体(P1、P2、F1、F2、F2∶3),采用植物数量性状主基因+多基因混合遗传模型对群体的单性结实性进行多世代联合分析.结果表明:雌雄同株黄瓜单性结实性表现为不完全显性遗传,符合D-2遗传模型,受1对加性主基因+加性-显性多基因控制.主基因加性效应值为14.7,多基因加性效应值为20.9,多基因显性效应值为25.8.F2的遗传率为56.6%,F2∶3的遗传率为48.7%.因此,对雌雄同株黄瓜单性结实性的遗传改良,可选择强单性结实性材料,通过杂交、回交转移主基因,达到选育强单性结实性材料目的.     

白菜叶裂数性状主基因+多基因遗传分析

以叶片全缘的大白菜自交系(P1)和叶缘深裂的欧洲白菜型油菜自交系(P2)杂交所获得的6个基本世代(P1、P2、F1、B1、B2、F2)为材料,应用主基因+多基因混合遗传模型对白菜叶裂数进行遗传分析。结果表明,白菜的叶裂数受2对加性-显性-上位性主基因+加性-显性多基因的控制,第1对主基因加性效应为-1.154 7,显性效应为-1.516 8;第2对主基因的加性效应为-1.154 8,显性效应为1.034 9;多基因加性效应为0.591 9,显性效应为1.145 2,2对主基因间存在明显的交互作用。B1、B2和F2世代叶裂数的主基因遗传率分别为88.48%、90.40%、93.03%;多基因遗传率分别为4.114%、0、0。B1、B2、F2世代叶裂数表现出较高的主基因遗传率,受环境影响较小。在白菜叶裂数性状的改良中应以主基因为主,并适于早代选择。     

大白菜抽薹性状的主基因＋多基因遗传分析

以大白菜易抽薹自交系06S1703和耐抽薹自交系06J32形成的P1、P2、F1、F2、B1和B2等6个世代为材料,应用主基因+多基因多世代联合分析方法,对大白菜抽薹性状进行了研究.结果表明,大白菜的抽薹性受2对加性-显性-上位性主基因+加性-显性-上位性多基因控制,其中2对主基因的加性效应值分别为-3.575 8和-13.619,显性效应值分别为-3.755 2和-2.257 7.B1、B2和F2世代的主基因遗传率分别为87.95%、95.13%和96.25%,只在B1群体中检测到多基因效应,遗传率仅为1.39%,说明大白菜的抽薹性是以主基因遗传为主,可以进行早期选择.     

一个新的抗玉米矮花叶病基因位点的微卫星标记

通过混合遗传模型P1、P2、B1、B2、F1、F2 6世代联合分析发现, 玉米(Zea mays L.)自交系黄早四对玉米矮花叶病B株系的抗性是由一对主基因和多基因共同控制,从而鉴别出一对主效基因的存在;利用位于第六染色体上的27对微卫星标记,对黄早四×Mo17的 F2群体进一步分析,筛选出两个与主效抗病基因(mdm1(t))紧密连锁的微卫星标记phi077和 bnlg391,它们在分子图谱上的顺序为phi077-mdm1(t)-bnlg391,两个区间的遗传距离分别是4.74 centiMorgan (cM)和6.72 cM.     

玉米自交系CML470抗南方锈病基因的定位

南方锈病是我国玉米产区的主要病害,玉米抗病品种的利用是控制其为害的一条最为安全和经济的途径。但是,在我国当前的玉米育种中,所利用的玉米南方锈病基因多来自美国杂交种78599等。为寻找新的南方锈病抗病基因,本研究对CIMMYT自交系CML470的抗性进行了遗传分析。结果发现CML470的抗性由一个显性抗病基因（定名为RppC）控制,该抗病基因被定位于10号染色体短臂端部,位于SSR标记umc1380和umc1291之间,分别与两标记相距3.5 cM和8.8 cM。通过回交,并利用分子标记辅助选择,RppC被转移到了优良自交系昌7-2中。     

一个新的抗玉米矮花叶病基因位点的微卫星标记

通过混合遗传模型P1、P2 、B1、B2 、F1、F2 6世代联合分析发现 ,玉米 (ZeamaysL .)自交系黄早四对玉米矮花叶病B株系的抗性是由一对主基因和多基因共同控制 ,从而鉴别出一对主效基因的存在 ;利用位于第六染色体上的 2 7对微卫星标记 ,对黄早四×Mo17的F2 群体进一步分析 ,筛选出两个与主效抗病基因 (mdm1(t) )紧密连锁的微卫星标记phi0 77和bnlg391,它们在分子图谱上的顺序为phi0 77 mdm1(t) bnlg391,两个区间的遗传距离分别是 4.74centiMorgan (cM)和 6 .72cM。     

六种藓类植物茎的比较解剖学研究

通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.     

Photoregulation of seed germination of wild-type and of an aurea-mutant of tomato

Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m⁻² s⁻¹. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to P_fr.     

Cause of Senescence of Nine Sorts of Flowers

The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.     

龙胆科药用植物化学成分的研究现状

龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。     

Interconnection of parameters of regulation system of lipid peroxidation and of morphophysiological parameters of mouse liver

A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.     

The effects of glutamine of the maintenance of embryogenic cultures of Cryptomeria japonica

Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l⁻¹ glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l⁻¹) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.     

Specificity of action of piperidylcholine derivatives as substrates of cholinesterases of various origin

The review deals with study of enzymologic properties of a novel highly specific acetylcholinesterase substrate, N-(β-acetoxyethyl) piperidinium iodomethylate (“piperidylcholine”), and its 30 derivatives that were tested as effectors of cholinesterases of mammals and various species of Pacific squids. It was proven for the first time that responsible for specificity of action was structure of cyclic ammonium grouping of the alcohol part of molecule of the ester substrate. Analysis of specificity is performed based on enzymatic hydrolysis parameters—activity of catalytic center of cholinesterases and bimolecular constant of the reaction rate that are determined at optimal and low substrate concentrations. Among the specially synthesized group of thioester compounds there is revealed one more highly specific acetylcholinesterase substrate—N-(β-acetoxyethyl) piperidinium.     

Physiological characteristics of various species of strains of carboxydobacteria

Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H₂-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H₂ with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD⁺, FMN⁺, and NAD(P)⁺ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H₂OCO₂+2H⁺+2e^- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation     

Modulation of allostery of pyruvate kinase by shifting of an ensemble of microstates

Since the introduction of the concepts of allostery about four decades ago, much advancement has been made in elucidating the structure-function correlation in allostery. However, there are still a number of issues that remain unresolved. In this review we used mammalian pyruvate kinase (PK) as a model system to understand the role of protein dynamics in modulating cooperativity. PK has a triosephosphate isomerase (TIM)(α/β)₈ barrel structural motif. PK is an ideal system to address basic questions regarding regulatory mechanisms about this common (α/β)₈ structural motif. The simplest model accounting for all of the solution thermodynamic and kinetic data on ligand-enzyme interactions involves two conformational states, inactive E^T and active E^R. These conformational states are represented by domain movements. Further studies provide the first evidence for a differential effect of ligand binding on the dynamics of the structural elements, not major secondary structural changes. These data are consistent with our model that allosteric regulation of PK is the consequence of perturbation of the distribution of an ensemble of states in which the inactive E^T and active E^R represent the two extreme end states. Sequence differences and ligands can modulate the distribution of states leading to alterations of functions. The future work includes: defining the network of functionally connected residues; elucidating the chemical principles governing the sequence differences which affect functions; and probing the nature of mutations on the stability of the secondary structural elements, which in turn modulate allostery.