BTH对小麦叶片防卫相关酶的系统诱导作用

用0.4 mmol/L的苯并噻二唑(BTH)溶液处理小麦幼苗第1叶和第2叶2 d后接种白粉菌,比色法测定第3叶接种前后过氧化物酶(POD)、苯丙氨酸解氨酶(PAL)、几丁质酶和β-1,3-葡聚糖酶的活性,结果表明BTH处理或接种均可使这4种酶活性升高。BTH诱导酶活性的系统增强与小麦对白粉病的诱导抗性密切相关。     

毛头鬼伞多糖对烟草酶活性和同工酶谱的影响

分析了毛头鬼伞(Coprinus comatus)真菌多糖诱导烟草对烟草花叶病毒(TMV)抗性过氧化物酶(POD)、多酚氧化酶(PPO)、苯丙氨酸解氨酶(PAL)、几丁质酶、-β1,3-葡聚糖酶活性的变化。结果表明,毛头鬼伞多糖可提高POD、PPO、PAL、几丁质酶和-β1,3-葡聚糖酶的活性,接种TMV后毛头鬼伞多糖处理的烟草酶活性显著高于不处理者。上述结果提示,毛头鬼伞多糖处理后烟草酶活性的增强可能与其诱导烟草获得抗性有关。     

纯氧对采后杨梅果实腐烂的抑制与抗病相关酶的诱导

为研究高氧对抑制果实腐烂的作用及其与抗病相关酶活性诱导的关系,将杨梅果实采后在5℃用纯氧或空气(对照)处理12 d.结果表明,纯氧处理可显著抑制果实腐烂发生,贮藏12 d后对照果实的腐烂指数达到54%,而处理果实仅为17%.纯氧处理在贮藏前期可诱导杨梅果实几丁质酶和β-1,3-葡聚糖酶活性的升高,并在第6天时达到高峰.另外,纯氧处理增加了苯丙氨酸解氨酶和过氧化物酶的活性及总酚含量,并在整个贮藏期间一直高于对照水平.这些结果表明,高氧抑制杨梅果实腐烂的作用与诱导与抗病相关的酶的活性升高密切相关,抗病性诱导是高氧抑制杨梅果实腐烂的重要原因.     

水稻抗稻瘟病与苯丙氨酸解氨酶及过氧化物酶活性的相关性

已知苯丙氨酸解氨酶(PAL)和过氧化物酶(POD)与水稻抗稻瘟病有密切相关,水稻受到稻瘟病菌(Pyricularia oryzae)侵染时,体内PAL与POD活性会发生显著变化。本文采用30个水稻(Oryza sativa)品种为材料,选择经常规浸种、催芽、生长较一致的种子,每一品种     

壳寡糖诱导黄瓜抗黄瓜黑星病的初步研究

本文研究了壳寡糖诱导黄瓜对黑星病的抗性作用。利用6 mg/mL壳寡糖溶液对苗期黄瓜诱导,进行病情调查统计及测定处理前后黄瓜叶片的主要防御酶系———苯丙氨酸解氨酶,过氧化物酶,多酚氧化酶,超氧化物歧化酶,过氧化氢酶的活性变化。结果显示,壳寡糖对黄瓜黑星病在10 d和17 d的诱抗效果分别为60.25%和47.59%,且作为诱导因子可显著提高黄瓜叶片内苯丙氨酸解氨酶(PAL)活性,过氧化物酶(POD)、多酚氧化酶(PPO)、超氧化物歧化酶(SOD)活性也有所提高,但叶片内过氧化氢酶(CAT)活性无较明显变化。研究结果表明壳寡糖对黄瓜抗黑星病产生诱导作用,为研究壳寡糖作为新型生物农药提供了依据。     

高温诱导黄瓜抗霜霉病机理

研究了高温对黄瓜霜霉病菌致病力的影响以及高温控制霜霉病发生的效果.结果表明,40 ℃高温处理2 h和45 ℃处理1 h对黄瓜霜霉病的诱导抗病性作用最明显,其在接种后4 d时的防效分别为58.40%和45.81%,到接种后6 d时,防效分别下降为39.35%和37.65%.经高温诱导后,过氧化物酶（POD）、苯丙氨酸解氨酶(PAL)、几丁质酶（Cht）、β-1,3-葡聚糖酶（Glu）活性均显著高于对照,与未诱导植株相比,高温诱导后叶片组织的细胞壁表面有大量木质素沉积,表明高温处理后黄瓜表现出对霜霉病的抗病性.     

分根培养系统中AM真菌抑制大豆胞囊线虫病的效应

在分根培养系统中将大豆(Glycine max Merrill)幼苗接种丛枝菌根(Arbuscular mycorrhiza,AM)真菌摩西球囊霉(Glomus mosseae)、幼套球囊霉(G.etunicatum)或/和大豆胞囊线虫(SCN,Heterodera glycines)后,定期测定大豆根系中AM真菌及线虫侵染率、病情指数、过氧化物酶(POD)、苯丙氨酸解氨酶(PAL)、β-1,3-葡聚糖酶及几丁质酶活性的动态变化。结果表明,将大豆胞囊线虫与AM真菌接种于分根培养系统同一室或分别接种于不同室,AM真菌均能显著降低大豆病情指数和线虫侵染速率,且将二者接种同一室处理的效果大于不同室处理;与只接种SCN的处理相比,接种摩西球囊霉和幼套球囊霉3周后在同室接种SCN处理的根围土壤中胞囊数、根上胞囊数和根内线虫数分别降低了47.4%、58.9%、46.6%和50.5%、67.0%、57.5%,表明AM真菌能显著抑制线虫的发育;摩西球囊霉和幼套球囊霉在一定时间段内诱导了大豆根系过氧化物酶、苯丙氨酸解氨酶、β-1,3-葡聚糖酶及几丁质酶的活性。摩西球囊霉和幼套球囊霉能够诱导大豆植株抵抗大豆胞囊线虫的侵染,既能在同一室的根围局部与SCN竞争侵染位点,又能对不同室的根系诱导产生防御性酶,推测摩西球囊霉和幼套球囊霉拮抗SCN的效应既是局部的,也是系统性的。     

两个紧密连锁的小麦苯丙氨酸解氨酶基因的分离与鉴定

利用一个小麦苯丙氨酸解氨酶基因PCR片段为探针,从小麦核DNA基因库中筛选出一个阳性噬菌体克隆,该克隆含有两个高度同源、紧密连锁、转录方向相同的小麦苯丙氨酸解氨酶基因PAL1与PAL2,它们之间的核酸序列同源性。为93％,相距约7kb,利用PAL1特异片段进行Southern分析,表明该基因在小麦基因组中具有多个拷贝。Northern杂交表明,经秆锈菌接种诱导,苯丙氨酸解氨酶基因在一对小麦抗-感近等基因系中差异表达：抗病等基因系中国春-Sr11携带与接种菌无毒性基因P11相对应的抗病基因Sr11,在接种4d后开始诱导表达,8d后表达量更高;而缺少抗病基因的感病系中国春-sr11接种6d后才开始表达,8d后的表达量与抗病系中6d时相当。用秆锈菌诱导物和几丁质寡聚物处理小麦悬浮细胞,均可在2h内激活苯丙氨酸解氨酶基因表达,但真菌诱导物在早期的诱导活性显著高于几丁质寡聚物。从转录水平证实了小麦苯丙氨酸解氨酶基因在秆锈菌诱导的抗性反应中具有重要作用。     

真菌源激发子对采后葡萄果皮抗性产生的诱导

利用细胞壁提取法从葡萄采后致病菌Alternaria alternate(Fr．)Keissl中提取出激发子。在采前一周用激发子处理葡萄,研究激发子诱导葡萄采后抗病效果。结果表明：葡萄经激发子处理后,果皮内与抗病有关的过氧化物酶(POD)、多酚氧化酶(PPO)和苯丙氨酸解氨酶(PAL)活性显著增强,酚类物质和木质素含量也显著提高,贮藏期自然发病率和发病指数降低,其中以125μg·mL-1处理效果最好,果实发病率和发病指数比对照降低500％左右。     

狭叶红景天愈伤组织中红景天甙含量及相关代谢酶活力的研究

室温下分别对狭叶红景天的茎和叶进行愈伤组织诱导,在24C和4C进行继代培养,测定其苯丙氨酸解氨酶、肉桂酸-4羟化酶和酪氨酸解氨酶的活性,并利用高效液相色谱法测定其红景天甙含量。结果表明：培养温度和愈伤组织的外植体来源均影响红景天甙的含量和3种代谢酶的酶活力;在24C和4C温度条件下,相同外植体来源的愈伤组织叶中和相同培养温度条件下的茎和叶2种不同来源外植体的愈伤组织中,红景天甙含量和3种代谢酶活力之间均存在显著性差异。     

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.     

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.     

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.