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1.
Wang G  Lin Q  Xu Y 《Phytochemistry》2007,68(15):2112-2117
Tetraena mongolica Maxim is a narrowly monotypic genus of Zygophyllaceae found in a very limited area in the western part of Inner Mongolia, China. The plant is called "oil firewood" and its stems and branches are used as fuelwood. As triacylglycerol (TAG) is the main component of the plant oil, the TAG content was analyzed, as were the distribution of oleosomes in different tissues of the stem. This was in order to ascertain whether the term "oil firewood" referred to this storage lipid. Stems of T. mongolica indeed contained high levels of TAG (approximately 46 mg/g of dry matter or DM). The concentration of TAG in phloem (90 mg/g of DM) was much higher than that in xylem (20mg/g of DM), and semi-thin sections stained by Sudan Black B showed that almost all cells in the phloem contained oleosomes whereas in the xylem, oleosomes were found only in parenchymatous cells. These results suggest that T. mongolica has a high capacity to accumulate TAG in its stem cells.  相似文献   

2.
Cao Rui 《西北植物学报》2007,27(8):1689-1689
Tetraena mongolica Maxim. is the only member of the genus Tetraena that belongs to the family Zygophyllaceae. It is characterized by the following features: small deciduous shrubs, 30-50 cm tall, much branched;leaves paripinnate,opposite on current year branches,and fascicled on old branches; leaflets 2,  相似文献   

3.
濒危植物四合木(Tetraena mongolica)为我国特有的蒺藜科单种属落叶小灌木.对四合木林地昆虫群落进行了调查,共得昆虫标本11363号,263种.隶属于67个科(或总科)11个目.同翅目的个体数量和优势度指数最高;膜翅目的物种丰富度和多样性指数最大;双翅目的均匀度最大.数量优势类群(>10%)为木虱和叶蝉类,常见类群(1%~10%)是象甲、小蜂、粒脉蜡蝉、拟步甲、蚂蚁、蝽科、皮蝽、盲蝽、斑翅蝗科昆虫.营养结构中植食性类群在种类和数量上占绝对优势,其中的吸食类昆虫优势度最大;天敌昆虫以寄生性类群为主,多样性最高;捕食性和中性昆虫的种类和数量相对较少,但捕食者的均匀度最高.灌木层与草本层相比,灌木层昆虫群落的物种丰富度和个体数量明显占优;优势种的优势度大.而草本层昆虫群落的多样性和均匀度高.2层整体的相似性低.膜翅目的共有种最多.  相似文献   

4.
从胚胎学特征探讨四合木的系统位置   总被引:7,自引:2,他引:5  
本文从胚胎学特征探讨了四合木的系统位置。胚胎学研究表明,四合木与蒺藜利具较近亲缘关系,但又有明显区别。表现为。四合木花药壁发育为基本型,绒毡层细胞多数具单核,心皮合生但深裂至近基部,胚株直生,具较长珠柄,无承珠盘,无珠被绒毡层,只具一列线形大孢子四分体,成熟胚囊为四细胞(四核),珠被在胚胎发育过程逐渐退化,因此,成熟种子中只具外珠被内层残迹;胚乳大部分细胞解体,而外缘胚乳细胞特化,在成熟种子中代替种皮起保护功能。因此,四合木是否应从蒺藜科分出而另列一种,值得进一步研究。  相似文献   

5.
在光学显微镜和扫描电子显微镜下观察了蒺藜科四合木属四合木(Tetraena mongolica Maim.)木材结构.其导管分子直径小,管壁厚,分布密度高,分子短,端壁几乎水平,具单穿孔;管间纹孔为对列或互列的具缘纹孔;韧性纤维短、壁厚、壁上有较少的单纹孔;同型单列射线、分布密度高;轴向薄壁组织散生或傍导管生.这些表明四合木的木材解剖特征是与干旱环境条件是相适应的.  相似文献   

6.
珍稀特有植物四合木研究进展   总被引:6,自引:0,他引:6  
综合述评了珍稀特有植物四合木在形态与解剖学、孢粉学、细胞学、种子表皮微形态学、胚胎学、生理学、生物学、生态学、遗传多样性、植物化学、濒危原因及保护途径方面的研究现状,展望了未来的研究方向,认为种群生存力分析、种质保存及人工更新方法、生态适应的分子生物学机理及其生境适宜性评价应是今后四合木研究的主要方向.  相似文献   

7.
运用压力室-容积技术(P-V技术)对西鄂尔多斯地区特有的濒危植物四合木(Tetraena mongolica Maxim.)和生长于同一生境的近缘种霸王(Zygophyllum xanthoxylon (Bunge) Maxim.)的7个水分关系参数饱和含水量时最大渗透势(Ψssat) 、初始质壁分离时的渗透势(Ψstlp) 、初始质壁分离时渗透水相对含量(ROWCtlp) 、初始质壁分离时的相对含水量(RWCtlp) 、质外体水的相对含量(AWC) 、束缚水与自由水的比值(Va / V0),以及细胞最大弹性模量(εmax)进行了测定,同时利用Li-6400光合作用测定系统测定了二者叶片气体交换参数的日变化,从生理生态学角度探讨了二者生存力、适应力的差异。结果表明:1)四合木的εmax、ROWCtlp值和RWCtlp值均显著低于霸王,而ΨssatΨstlp值、AWC和Va / V0高于霸王。二者保持膨压的能力和方式不同,四合木表现为较小的细胞体积和较强的持水能力,主要以高的组织弹性来保持膨压,而霸王主要以增加细胞质浓度的渗透调节来维持膨压,弹性调节较弱。且四合木保持最大膨压的能力和维持最低膨压的极限渗透势低于霸王,耐旱性弱于霸王。2)自然条件下,四合木和霸王叶片的光合速率(Pn)、蒸腾速率(Tr)日进程均呈"双峰"曲线,主峰出现在11:00时,次峰出现在15:00时左右,光合作用的午间降低是由气孔导度(Gs)降低造成的。二者相比,四合木光合速率和水分利用效率(WUE)低于霸王,光合能力和对干旱环境适应能力弱于霸王。研究表明四合木在生理生态学方面的生存力、适应力弱于霸王。  相似文献   

8.
四合木繁殖特性的研究   总被引:14,自引:1,他引:13  
对四合木(Tetraena mongolica Maxim)的系列特性做了综合研究。结果表明,四合具有有性和无性生殖2种形式的繁育系统,以有性生殖占主导地位。该种成熟的花粉及柱头表面均较平滑,开花时花柱伸和苴柱头稍有膨大,但估不发达。子 在部具花盘。子房壁和花盘执行蜜腺功能。开花前,密腺开始发育,花后密腺成熟并有分泌行为。套袋实验发现,四合木传粉方式以异花传粉为主,传粉结束后统计,异花传粉结实率为  相似文献   

9.
报道了中国兰科植物一个分布新记录的属-指柱兰属和该属一新记录的种-指柱兰。  相似文献   

10.
Tetraena gaetula (Emb. & Maire) Beier & Thulin (Zygophyllum gaetulum Emb. & Maire, Zygophyllaceae) is an endemic plant from the southern Morocco. This plant is widely used in Moroccan traditional medicine as an antispasmodic and antidiabetic. Our work aims to evaluate several pharmacological properties of extracts of T. gaetula such pro- or antiproliferative, immunomodulatory, analgesic and antidepressant effects. Initially, we studied intraperitoneally the acute toxicity of aqueous extract of T. gaetula in mice; the lethal dose 50 is 1.2 g/kg of body weight. Our results also showed a stimulating proliferative activity of T. gaetula, particularly at 6 μg/μL of the proteic extract on T lymphocytes. However, this same concentration of proteic extract induced rather cytotoxicity on B cells and macrophages. Our ex vivo results showed a dose-dependent response: (i) stimulation of lymphocyte subpopulations and monocytes in a dose 600 mg/kg, and (ii) immunosuppression at a dose 300 mg/kg. The pharmacological results in vivo showed a pronounced antidepressant effect of the proteic extract at all doses. However, the aqueous extract showed analgesic and anti-depressant effects, mainly at doses 300 and 600 mg/kg.  相似文献   

11.
Wood of nine species of Krameria (including all clades proposed within the genus) reveals a few characters related to infrageneric systematics; most relate primarily to ecology and habit. Wood of Krameria closely fits quantitative data reported for desert shrubs. Lack of vessel grouping correlates with the presence of densely pitted tracheids. Wood xeromorphy in Krameria may relate in part to hemiparasitism. Tracheid presence may also account for relatively low vessel density. Wood anatomy of six species of Zygophyllaceae (including both genera of Morkillioideae) is compared with that of Krameriaceae because recent phylogenies propose that these two families comprise the order Zygophyllales. Several wood characters appear to represent synapomorphies reflecting this relationship. Differences in wood anatomy between Krameriaceae and Zygophyllaceae are believed to represent autapomorphies. Notable among these include Paedomorphic Type II rays (Krameriaceae), storying (Zygophyllaceae), presence of vestured pits (Zygophyllaceae), and differentiation into vasicentric tracheids and fibre-tracheids (Zygophyllaceae). The latter feature is referable to the concept of fibre-tracheid dimorphism. Recognition of Krameriaceae as separate from Zygophyllaceae is supported by wood characters. Wood of Zygophyllales does not conflict with the idea that the order belongs to rosids, with Malpighiaceae as the outgroup of Zygophyllales.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 257–270.  相似文献   

12.
四合木(Tetraena mongolica Maxim.)是内蒙古东阿拉善-西鄂尔多斯地区的特有珍稀植物,为古地中海孑遗物种.自然环境恶化和人类活动干扰,使其生境发生了严重的破碎化,甚至消失.有限的分子标记限制了对该植物种质遗传多样性和生存现状的认识.本研究通过转录组测序,构建了含有119603条Unigenes的四...  相似文献   

13.
中国特有种四合木种群遗传多样性的RAPD分析   总被引:13,自引:6,他引:7  
张颖娟  杨持 《生态学报》2002,22(11):1917-1922
采用随机扩增多态性 DNA(RAPD)技术检测了西鄂尔多斯高原特有种四合木种群 5个斑块的遗传多样性。2 2个扩增引物产生 1 1 6条带 ,Shannon信息指数和 Nei指数对 RAPD数据的分析表明 :四合木种群存在较高的遗传多样性 ,其中千里山斑块的遗传多样性和多态位点比例较高 ,石嘴山斑块的最低。遗传多样性的 86.5 %存在于斑块内 ,斑块间的遗传变异为 1 3 .5 %。遗传距离与地理距离无直接相关关系。这些结果说明 ,遗传多样性反映了四合木种群基因组 DNA存在较高的变异性 ;同时各斑块间存在一定的基因流 ,四合木各斑块可看成是处于同一种群的半隔离状态 (meta-种群 ) ,对四合木应注意保护遗传多样性丰富的 meta-种群。  相似文献   

14.
目的:通过分析花椒cpDNA trnL-F间隔区序列特点,探讨该序列在花椒与其混淆品鉴别中的意义.方法:对花椒及其混淆品进行cpDNA trnL-F间隔区序列比较研究.结果:花椒cpDNA trnL-F间隔区序列为349bp、AT百分比为62.1%.尽管花椒的果实在外部形态,物理特性上与混淆品差异较小,但在cpDNA trnL-F间隔区序列上却存在着显著而稳定的差异.该序列在属以下的分类阶元中同源性极高,可达100%.结论:根据cpDNA trnL -F间隔区碱基序列的差异,能有效地鉴别花椒及其属以上分类阶元的混淆品.  相似文献   

15.
双花木属植物潜在分布区模拟与分析   总被引:1,自引:0,他引:1  
孟艺宏  徐璕  姜小龙  徐刚标 《生态学报》2019,39(8):2816-2825
气候变化直接影响着物种的分布范围。了解气候变化对濒危物种分布区的影响,是开展保护生物学研究的基础。双花木属(Disanthus Maxim.) 1种1变种,隶属金缕梅科(Hamamelidaceae),为东亚特有濒危物种和典型的中-日间断分布成分,在研究东亚植物区系地理演化方面具有重要的科学价值。本研究基于双花木属植物19个当前居群分布点的气候变量,运用MaxEnt模型预测双花木属植物在末次盛冰期(约22000年前)、当前(1950—2000年)和未来(2060—2080年)气候情景下的潜在分布区的结果显示,受试者工作特征曲线下的面积(AUC=0.9999±0.0001)接近于1,表明MaxEnt模型的预测准确度极高;气候变量贡献率和Jackknife检验评估的结果显示,制约双花木属植物分布的主导气候变量是最湿月降水量和最干月降水量。采用ArcGIS 10.0中的ArcToolbox空间分析工具定量分析比较双花木属的分布动态,基于生境稳定性(N_(stab))、当前与其他时期分布区面积比(N_a)和扩张/收缩程度(N_e)的分析结果揭示,在双花木属植物进化过程中,分布范围经历了收缩过程;未来的温室气体排放量升高程度不同,其适生区呈现不同程度(30%—65%)收缩,特别是RCP 8.5气候情景下,我国武夷山山脉的潜在分布区有可能会丧失。探讨双花木属植物对不同时期气候变化的响应,重建冰期以来该属植物地理分布的变迁历史,分析限制其潜在地理分布的主导气候变量,可为双花木属植物保育措施的制定和东亚地区植物区系物种形成演化的研究提供理论参考。  相似文献   

16.
从我国蒺藜科特有属植物四合木(Taraena mongolica Maxim)的全株中首次得到了五种化合物。应用光谱等检测方法,对其结构进行了鉴定。分别鉴定为:十四碳酸月桂醇酯(1)、羽扇豆醇(2)、β-谷甾醇(3)、5,7,3',4'-四羟基-3-甲氧基黄酮(4)、5,7,4’-三羟基-3,3’-二甲氧基黄酮(5)。上述成分均为首次从四合木中得到。其中5,7,3’,4'-四羟基-3-甲氧基黄酮表现出较高的抗氧化活性。  相似文献   

17.
人为干扰对乌海市四合木小灌木景观的影响   总被引:2,自引:0,他引:2  
秦山  潮洛濛 《生态学报》2014,34(21):6346-6354
以乌海市四合木(Tetraena mongolica Maxim)为研究对象,利用2009年Quickbird高分辨率影像,结合四合木群落野外调查数据,对乌海市四合木分布区在不同人为干扰强度下的景观格局和群落进行研究。结果表明:人为干扰越强烈,四合木生境破碎化程度越严重。在植株生理年龄相近,生境相同时,四合木的高度、冠幅以及重要值随人为干扰加剧,变化趋势明显。受人为干扰程度越强地区,其物种丰富度指数越小,生物多样性越低。干扰强度发生变化时,Pielou均匀度指数均在0.77—0.90间。  相似文献   

18.
The classical and numerical taxonomy, palynology and the geographical distribution of the Genus Schizopepon are dealt with in the present paper. Having commented on various opinions regarding the systematic position of the genus, the present authors consider that C. Jeffrey’s treatment of Schizopepon as a new and monogeneric tribe, Schizopeponeae, should be supported. The gross morphological characters in the genus are assessed from the taxonomic point of view. Some characters, such as stamens with an elongated connective or not, different insertions of ovules and various forms of ovaries and fruits, may be used for distinguishing subgenera. The pollen grains of all the species were observed under light microscope (LM) and scanning electron microscope (SEM). The results show that a strong differentiation has taken place in the pollen of the genus, and in consequence it may be regarded as an important basis for dividing subgenera and species. Especially it should be pointed out that degrees of development of colpi and positions of ora are positively correlated with the external characters used for distinguishing subgenera. According to the morphological and palynological characters, the genus Schizopepon may be divided into three subgenera and eight species: 1. Subgenus Schizopepon: 5 species, S. bryoniaefolius Maxim., S. monoicus A. M. Lu et Z. Y. Zhang, S. dioicus Cogn., S. longipes Gagnep. and S. macranthus Hand.-Mazz.; 2. Subgenus Rhynchocarpos A. M. Lu et Z. Y. Zhang: 1 species, S. bomiensis A. M. Lu et Z. Y. Zhang; 3. Subgenus Neoschizopepon A. M. Lu et Z. Y. Zhang: 2 species, S. bicirrhosus (C. B. Clarke) C. Jeffrey and S. xizangensis A. M. Lu et Z. Y. Zhang. The 8 OTU’s including all the species of this genus and 31 characters, of which 16 are morphological characters and 15 palynological characters, were used in the numerical taxonomic treatment. After standardization of characters, the correlation and distance matrices were computed. The correlation matrices are made to test the various clustering methods. At last, the UPGMA clustering method was selected and its result is shown in the form of phenogram. The result of numerical analysis is similar to that of the classical classification. Schizopepon Maxim. is a genus of East Asia-Himalayan distribution. China has all 8 species and 2 varieties, of which 6 species are endemic. Based on the statistics of spedies number, the distribution centre of the genus is considered to be in the Hengduan Mountains (Yangtze-Mekong-Salwin water divides) and the adjacent areas of the southwest China.  相似文献   

19.
利用扫描电子显微镜对东亚特有植物黄三七(Souliea vaginata(Maxim.) Franch.)茎的次生木质部离析材料进行了观察,结果表明,黄三七茎次生木质部中的导管分子端壁上具网状穿孔板(麻黄式穿孔板)、梯状穿孔板、网状-梯状混合穿孔板、网状-梯状-单穿孔混合型穿孔板、梯状-单穿孔混合型穿孔板及单穿孔板,同时也观察到了端壁多穿孔板和侧壁穿孔板,并对不同类型穿孔板中纹孔膜的残留也进行了观察。其中,网状穿孔板、各种过渡类型的穿孔板均为毛茛科植物中首次报道。根据观察结果,对导管分子穿孔板的演化及黄三七属植物的系统位置进行了分析。  相似文献   

20.
Determination of some water relations parameters of 9 shrubs with the Pressure-volume technique has shown that there were considerable variations in the water relations parameters of different shrubs and that some parameters were indicative for their adaptations to the ecological conditions. It has been found that two desert shrubs, Tetraena mongolica Maxim. and Zygophyllum xanthoxylon (Bge.) Maxim., exhibited strong ability of drought tolerance, whereas the typical sandy shrubs were quite diverse in adaptation strategy. Salix psammophila C. Wang et Ch. Y. Yang, Artemis& ordosica Krasch., Caragana intermedia Kuang et H. C. Fu and Ammopiptanthus mongolicus (Maxim.) were more or less close to each other in water relations parameters. Their фπ, p ranged from - 1.4 MPa to -2.4MPa, and Vp/Vo lay between 62% and 76%. However, some special features of adaptation were found in the other three species, e.g., Sabina vulgaris Ant., Hedysarum mongolicum Turcz. and Artemisia sphaerocephala Krasch.  相似文献   

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