籼型杂交稻光合特性的配合力分析

以6个籼型杂交稻三系不育系和5个恢复系按不完全双列杂交设计配制的30个杂交稻组合及其亲本品种为材料,对其光合性状进行了测定和分析,结果表明:(1)杂交稻组合的光合特性存在显著或极显著的组合间遗传差异,光合特性的遗传变异主要来自基因的非加性效应;(2)胞间CO2浓度、蒸腾速率、叶绿素a、叶绿素b和类胡萝卜素含量受不育系的影响大于恢复系,而气孔导度、叶绿素a+b含量受恢复系的影响大于不育系;(3)杂交稻光合性状的广义遗传力均大于狭义遗传力,各性状主要受基因互作及环境的影响。狭义遗传力的大小依次为叶绿素b、叶绿素a+b、叶绿素a、气孔导度、胞间CO2浓度、类胡萝卜素和蒸腾速率,这些性状具有中等遗传力;(4)9个光合性状杂交稻F1表型值与父母本一般配合力效应值之和的相关系数均达极显著水平。因此,可以根据父母本一般配合力效应值之和来预测杂交稻组合光合性状的表现,有利于高效选育高光效杂交稻组合。     

甘薯品种主要性状的遗传力和相互关系的研究

甘薯属异花授粉作物,其遗传基础较复杂。对甘薯的遗传规律,国内外均有研究和报道,但对品种间不同性状的遗传力及其性状间的内在联系,所见报道甚少。本试验以15个甘薯品种为材料,就14个主要性状的广义遗传力等进行研究,以期为甘薯的育种工作提供理论依据。     

甘蔗杂交后代蔗汁品质性状的遗传分析

以4×3不完全双列杂交(NCⅡ)选配的12个杂交组合后代为材料,对蔗汁锤度、旋光读数、转光度、蔗汁蔗糖分、视纯度和重力纯度等6个品质性状进行配合力和遗传力分析。结果表明,品质性状的遗传主要由基因加性效应引起,其中蔗汁锤度、旋光读数、转光度、蔗汁蔗糖分主要由父本基因加性效应引起。CP72-330、HoCP93-750、桂糖91-116和粤糖92-1287等4个亲本的品质性状一般配合力(gca)为正值且较大,是配合力较好的高糖亲本。CP72-330×桂糖91-116及HoCP93-750×粤糖92-1287的品质性状特殊配合力(sca)相对效应值均为正值且较大,杂交后代品质性状平均值也较高,为较好的高糖杂交组合。品质性状父本gca方差大于母本gca方差,亲本gca方差为组合sca方差的7-28倍,广义遗传力(hB2)为58%-68%,狭义遗传力(hN2)为56%-60%,属于遗传能力较强的品质性状。     

甘薯品种主要性状的遗传力和相互关系的研究

甘薯属异花授粉作物,其遗传基础较复杂。 对甘薯的遗传翔律,国内外均有研究和报道,但 对品种间不同一G状的遗传力及其性状间的内在 联系,所见报泣甚少。本试验以15个甘薯品 种为材料,就14个主要性状的广义遗传力等 进行研究,以期为甘薯的育种工作提供理论依 据。     

花生主要性状遗传力和相关性的研究

1.材料为1960～1961年杂交的三个组合。选用的亲本,为生产应用的两个主要类型(普通型、珍珠豆型)。这两个类型的品种,在生态和生物学特性上都有比较明显的区别。采用这两个类型进行品种间有性杂交,选出的优良品种也较多。 2.花生性状遗传力的大小,在不同的估算方法(广义法及上下代亲子相关法)间,除总分枝、总果枝出入较大外,其他几个性状都有大体一致的趋势。百果重、饱果数、单株结果数、生育日数、主茎高等性状遗传力较高,秕果数、单株产量等性状的遗传力较低。 3.单株产量,从世代间(F_(2-3))的遗传力来看是很弱的,因此,对于单株产量的选拔标准不宜控制过严,特别是双亲生态型相差悬殊的组合,更有必要放宽选拔的标准。此性状于第二代通过直接选择是无效的,但与单株产量有密切关系的却有几个性状,如单株结果数、饱果数等。因此,通过间接性状的选择,亦可能选择出单株生产力高的优良品系。 4.产量与其他性状的相关性表明,单株结果数越多,产量越高,饱果数越多,产量越高,说明果多果饱是决定产量高低的主要因素。 5.利用变异系数的平方代替相应的变量来估算广义遗传力,可以起到一定的矫正作用。     

成都白鸡某些性状遗传力的几种估测方法的比较

性状遗传力是进行选种、育种工作不可缺少的遗传参数。有关鸡的经济性状遗传力,国外已有许多研究,而国内这方面的报道较少。由于不同品种同一性状的遗传力不尽相同,因而国外估测的有关性状遗传力只能供我们参考。为使成都白鸡今后的选育工作更为科学可靠,有必要正确估测成都白鸡某些主要经济性状的遗传力。关于估测性状遗传力的方法,许多学     

氮素水平对籼、粳稻主要数量性状遗传力的影响

本文在0、35、75、105公斤/公顷4个纯氮水平下,考察了籼、粳稻各10个品种株高、结实率等12个主要数量性状遗传力的变化规律。结果表明,性状不同,其遗传力受氮素的影响程度也不同,两亚种皆然,但籼稻的遗传力均比粳稻的高,籼稻群体比粳稻群体更具遗传多样性。因此,育种实践中,应将目标性状设在最宜于其遗传信息充分表达的氮素水平下进行选择。     

氮高效玉米主要性状的遗传分析

采用两个氮高效玉米杂交组合的P1、P2、F1、F2、B1、B2世代,随机区组试验设计,对氮高效玉米主要性状的遗传力进行了研究。研究结果表明,不同氮水平下氮高效玉米各性状的遗传力是不同的。低氮处理中,广义遗传力介于0.78～0.46之间,狭义遗传力介于0.68～0.23之间;高氮处理中,广义遗传力介于0.76～0.49之间,狭义遗传力介于0.67～0.25之间。低氮条件下,氮高效玉米主要性状中抽丝期穗位叶叶绿素含量、氮效率、穗重和穗位叶叶面积,高氮条件下,抽丝期生物量、穗重、抽丝期穗位叶叶绿素含量和成熟期生物量等性状的遗传力较高,可分别在低氮、高氮条件下,对其进行早代选择。     

北美驼绒藜主要性状遗传变异特性的初步研究

对北美驼绒藜的4个世代12个主要性状遗传变异特性初步分析结果表明:在世代内12个主要性状变异都不显著,在世代间除枝条节数和着生雄花节数外,其它10个性状变异程度都达到了显著或极显著水平,表明北美驼绒藜各性状主要变异来自世代间;10个性状表型变异系数和遗传变异系数总体趋势基本一致,但程度上存在差异,说明这些性状遗传变异潜力较大;株高、叶腋雌花数、叶宽、再生小枝数性状遗传力较高(72-62),其变异主要是遗传因素决定,而叶长、株幅性状遗传力较低(16-14),其变异主要是环境因素决定。     

氮素水平对釉、粳稻主要数量性状遗传力的影响

本文在0、35、75、105公斤／公顷4个纯氮水平下,考察了仙、粳稻各10个品种株高、结实率等12个主要数量性状遗传力的变化规律。结果表明,性状不同,其遗传力受氮素的影响程度也不同,两亚种皆然,但釉稻的遗传力均比粳稻的高,釉稻群体比粳稻群体更具遗传多样性。因此,育种实践中,应将目标性状设在最宜于其遗传信息充分表达的氮素水平下进行选择。     

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.     

真菌类遗传学分析的知识结构教学

本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.     

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.     

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.     

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。     

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.