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1.
从石竹科植物多荚草(Polycarpon prostratum(Forssk.)Aschers.et Schwein.ex Aschers)中分离得到3个新的柴胡皂甙类化合物:prostratoside A ̄C(1 ̄3)。它们的结构通过波谱方法分别鉴定为:3-O-{β-D-xylopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)-「β-D-glucopyranosy  相似文献   

2.
水稻重复序列RRD3在转基因植物中的启动子功能   总被引:10,自引:0,他引:10  
来源于水稻(Oryza sativa L.)的一个820bp多拷贝重复序列RRD3,含有植物启动子TATA-box、CAAT-box等特征保守基元。用RRD3取代Ti载体pB1121中的CamV 35S启动子,通过植物转化鉴定RRD3的启动子功能。组织化学分析表明,根癌土壤杆菌(Agrobacterium tumefaciens(Smith et Townsend) Conn)LBA4404转化后  相似文献   

3.
刺槐宽叶和四倍体无性系的组织培养   总被引:13,自引:0,他引:13  
1植物名称刺槐(Robiniapseudoacacia)优良无性系:Tetraploidlocust、Glgastypelocust。2材料类别带腋芽的茎段。3培养条件(1)启动培养基:MS+6-BA0.25mg·L-1(单位下同)+NAA0.05。(2)分化培养基和继代培养基:MS+6-BA0.5+NAA0.1+AgNO310,MS+6BA0.5+NAA0.1。上述培养基均添加3%蔗糖、0.6%琼脂。(3)生根培养基:1/2MS+IBA0.2+NAA0.2,添加2%蔗糖0.6%琼脂。培养基pH…  相似文献   

4.
葡萄糖淀粉酶研究进展   总被引:8,自引:1,他引:7  
葡萄糖淀粉酶研究进展杨依军,李多川,沈崇尧(北京农业大学植物科技学院.北京100094)葡萄糖淀粉酶(GlucoamvlaseE·C3.2.1.3),又称淀粉葡萄糖苷酶(Amyloglucosidase)或γ-淀粉酶(γ-amylase),简称糖化酶...  相似文献   

5.
本通过扫描电子显微镜,对东北地区蒿属(Artemisia)植物,莳萝蒿组(A.sect.Absinthium DC),艾蒿组(Sect.Abrotanum Bess),艾组(Sect.Artemisia),龙蒿组(Sect.Dracumculus Bess),牡蒿组(Sect.latiobus Y.R.Ling)36种成熟代表植物叶表皮形态学特征进行了详尽的比较研究。其中表皮细胞大小、形状不等。  相似文献   

6.
不同光合途径植物叶圆片对光氧化作用响应的比较   总被引:9,自引:0,他引:9  
光合C3途径植物花生(ArachishypogaeaL.)、C4途径植物玉米(ZeamaysL.)和甘蔗(SacharumsinenseRoxb.)及CAM植物菠萝(Ananascomosus(L.)Mer.)的离体叶圆片经甲基紫精(MV)和强光的光氧化作用1h,出现不同程度的蛋白质、色素、膜脂的氧化与过氧化降解,呼吸增强,PSⅡ失活。花生光化学荧光猝灭系数(qP)下降时类胡萝卜素含量和非光化学荧光猝灭系数(qN)明显增高,暗下吸O2增强,通过活跃的天线猝灭和提高呼吸的方式耗散过剩的光化学能。C4植物也有增强吸O2以耗散部分光化学能的效应,但其蛋白质和膜脂降解程度比C3植物高,Fo升高而qN降至最低,表现较明显的光氧化损伤。菠萝的各项变化幅度小,有较强的抗光氧化性。  相似文献   

7.
对澳大利亚特产的Callitris属植物C.preissii,C.verrucosa,C.endlicheri(柏科)的核型进行了分析,后2种的为首次报道。它们的核型公式分别为K(2n)=22=22m(2SAT),22m(2SAT)和22m(6SAT),均属1A核型类型。染色体相对长度组成同是2n=22=10M_2+12M_1该3种及其他8种Calltris属植物一致的核型K(2n)=22m和1A类型的通常被认为是最对称和原始的。因此该属在柏科的系统发育上也许处于相当原始的地位。  相似文献   

8.
海南岛东部近海新第三纪孢粉植物群   总被引:3,自引:0,他引:3  
根据BD23-1-1井与孢子花粉共生的海相浮游有孔虫和钙质超微化石,论述了中国海南岛东部近海新第三纪各个时期的孢粉植物群特征。建立了4个孢粉组合,它们是:1.Quercoidites-Cupuliferoipolenites-Florshuetzia-Dicolpopolis组合(早中新世晚期);2.Dicolpopolis-Extra-punctatosporites-Taxodiaceaepolenites组合(中中新世早期);3.Abietineaepolenites-Polypodi-aceaesporites-Liquidambarpolenites组合(中中新世晚期至晚中新世);4.Abietineaepolenites-Persicarioipolis组合(晚中新世晚期至早上新世)。孢粉植物群反映了海南岛东部近海新第三纪的气候基本上一直比较温暖湿润,并且逐渐降温的历程。  相似文献   

9.
对青藏高原高山冰缘地区毛茛科3种特有植物的核型进行了分析。它们的核型公式(K)、染色体相对长度组成(C.R.L.)和核型不对称系数(As.K%)分别为:青藏金莲花Troliuspumilusvar.tanguticus:K(2n)=6m+8sm(2SAT)+2st,C.R.L.=4L+4M2+4M1+4S,As.K%=63.57,核型属2B型;甘青乌头Aconitumtanguticum为K(2n)=6m+10sm,C.R.L.=4L+8M1+4S,As.K%=62.54,2B型;单花翠雀花Delphiniumcandelabrumvar.monanthum为K(2n)=6m+8sm+2st,C.R.L.=4L+4M2+4M1+6S,As.K%=64.34,属3B型。经同相关近缘种核型资料比较,青藏金莲花核型不对称性和进化程度比金莲花T.chinensis低;甘青乌头的核型不对称性和进化程度在其近缘类群(乌头组Sect.Aconitum)已报道的种之内最低;单花翠雀花核型不对称性和进化水平比翠雀组(Sect.Delphinastrum)已报道的展毛翠雀花D.kamaoensevar.glabrescens、  相似文献   

10.
从短(PipermulesuaD.Don.)地上部分甲醇粗提取物中分离得到7个化合物,经波谱分析鉴定为:β-谷甾醇(1),retrofractamideA(2),chingchengenamideA(3),nectandrinB(4),(-)-nectandrinA(5),galgravin(6)。其中木脂素(4)、(5)系首次由胡椒属植物中分得。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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 Pfr.  相似文献   

14.
龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
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。  相似文献   

15.
16.
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
20.
真菌类遗传学分析的知识结构教学   总被引:5,自引:2,他引:3  
罗桂花 《遗传》2002,24(3):349-350
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.  相似文献   

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