首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 159 毫秒
1.
濒危物种小勾儿茶的重新发现   总被引:3,自引:0,他引:3  
在距离濒危物种小勾儿茶模式标本产地约130 km处的湖北省五峰县后河国家自然保护区中重新发现了小勾儿茶Berchemiella wilsonii (Schneid.) Nakai。威尔逊1907年在湖北省兴山县采集到小勾儿茶的模式标本有花,无果实。我们在五峰县采集了小勾儿茶的花和果实标本并对其果实特征予以补充描述。  相似文献   

2.
濒危植物小勾儿茶伴生群落特征研究   总被引:9,自引:5,他引:4  
从植物生活型、群落垂直结构、物种多样性以及群落稳定性4个方面研究小勾儿茶伴生群落特征,分析小勾儿茶在该生境幸存的原因。生活型谱反映出生境温热高湿且四季分明的亚热带气候特点;小勾儿茶处于群落顶层,能够获得充足的阳光;群落结构稳定、物种丰富。小勾儿茶的数量已极为稀少,应采取调查、保护和扩繁3种主要措施扩大其种群数量,即:(1)加大力度在相似的生境中寻找小勾儿茶;(2)对其生境加大保护力度;(3)开展种子生理方面的研究,探索有效的发芽途径,同时用组培的方法繁殖幼苗。  相似文献   

3.
对蓝钟花属(Cyananthus)11种植物的种子在体视显微镜和扫描电镜下的外部形态、内部结构以及微形态特征进行研究.结果表明:蓝钟花属种子呈窄卵形,表面光滑,颜色多为黑色、褐色至棕色,其中多年生组表面具有特殊黑色斑纹;胚属短小型,胚乳白色或棕色,胶质或脂质;种皮表面纹饰为条纹型,网壁螺旋排列或平行排列,又可细分为阔网状条纹、窄网状条纹与一般性条纹三种类型.种子形态在属下三组间差异明显,种子长度、表面颜色及表面纹饰为属内组的划分提供了重要依据.此外,一年生组各种在种子形态上分化最为明显,可能与其较强的适应性有关.  相似文献   

4.
苦草属植物体外部形态相似,叶线行或带形,野外难以直接鉴定到种,而雄花雄蕊数目、果实和种子的显微结构是苦草属(Vallisneria)植物物种的鉴别性特征之一。苦草属物种的雄花小,仅有1.5 mm,人工解剖雄花观察方法难以实现雄花雄蕊数目的识别;本研究采用雄株雄佛焰苞水培预培养技术获取自然开放的雄花并利用解剖学显微镜对3种苦草属植物雄花、果实和种子进行了解剖观察和研究。显微结构观察表明,苦草(V. natans)雄蕊1枚,果实圆柱形,表面光滑,种子无翅,具纵条纹;刺苦草(V. spinulosa)雄蕊2枚,果实三棱形,棱上具刺,种子具翅;密刺苦草(V. denseserrulata)雄蕊2枚,果实三棱圆柱形,表面光滑,种子无翅。依据文献,密刺苦草、刺苦草、长梗苦草(V. longipedunculata)和安徽苦草(V. anhuiensis)是安徽苦草属新分布记录种,其中长梗苦草和安徽苦草是分布于安徽的新种。  相似文献   

5.
濒危植物毛柄小勾儿茶种子休眠与萌发生理的初步研究   总被引:12,自引:1,他引:11  
毛柄小勾儿茶(Berchemiella wilsonii (Schneid.)Nakai var.pubipetiolata H.Qian)为中国特有种,国家三级保护植物。TTC染色法测得毛柄小勾儿茶种子的生活力较低,仅为32%,空粒和无生活力的种子分别为28%和40%,说明毛柄小勾儿茶发育完全的种子较少。种子吸水速度试验证明毛柄小勾儿茶种皮透水性较差,不利于种子萌发时对水分的吸收,发芽抑制物的生物鉴定结果表明,毛柄小勾儿茶种子的不同部位都存在发芽抑制物,且种胚中的含量最高,不利于种子的萌发,使毛柄小勾儿茶种子处于休眠状态之中。几种不同浓度GA。溶液浸种24h的预处理可以不同程度地提高毛柄小勾儿茶种子的发芽率和发芽指数,其中300mg/L GA3的效果最显著,并且300mg/L GA3的预处理可以在萌发初期(萌发前3天)显著地提高毛柄小勾儿茶种子中过氧化物酶、过氧化氢酶和脱氢酶的活性。毛柄小勾儿茶种子生活力低,且处于休眠状态,再加上与种子发芽力有关的几种酶的活性较低,致使毛柄小勾儿茶种子的发芽率较低,同时这些也是从种子萌发生理方面导致毛柄小勾儿茶濒危的重要原因。  相似文献   

6.
毛柄小勾儿茶 (Berchemiellawilsoniivar.pubipetiolata) 为我国分布于浙江、安徽局部地区的特有珍稀物种, 由于自身和人为干扰的原因, 该种受到灭绝威胁。该文在 2× 2联列表基础上, 应用 χ2 检验、联结系数 (AC) 分别检测了毛柄小勾儿茶在 4个分布点与群落中乔、灌两层植物的种间联结性。综合比较 χ2 检验与AC值的测定结果, 在 4个分布点, 毛柄小勾儿茶与群落中其它种群的关联情况十分相似 :1) 绝大多数种群与毛柄小勾儿茶的AC值在 - 0.2至 0.2之间, 即无关联 ;2 ) 与毛柄小勾儿茶存在显著关联的种群仅有一个或无 ;3) 优势种群与毛柄小勾儿茶关联小。这说明 4个分布点毛柄小勾儿茶在群落中都具有很大的独立性或随机性, 它只是群落的伴生种或偶见种。研究结果对为该物种制定合适的就地保护措施和恢复计划具有参考价值。  相似文献   

7.
在ArcGIS软件中,以中国鼠李科植物物种分布数据为基础,以县为基本单元,制作属的空间分布数据,从空间分布图中提取各属的斑块面积、周长、数目,计算属的Simpson均匀度指数、形状指数及最大斑块指数,分析中国鼠李科植物属的空间分布特点,为确定其空间分布最小范围、定量研究及植物的保护、利用、资源的开发和恢复提供依据。结果表明:①麦珠子属、对刺藤属、苞叶木属、小勾儿茶属、蛇藤属、咀签属和翼核果属为狭域属,马甲子属、猫乳属、雀梅藤属、枳椇属、勾儿茶属、枣属和鼠李属为广域属,狭域属和广域属均占中国鼠李科植物总属数的50%。狭域属的总面积小于30×104km2,其中小勾儿茶属主要分布在我国亚热带中部,其他狭域属主要分布在北回归线附近及其以南地区;广域属的总面积大于40×104km2,分布在我国大部分地区,西北地区呈零星分布。②中国鼠李科植物中,鼠李属的分布范围和总面积最大,几乎涵盖所有属的分布范围,它能体现出鼠李科植物在中国的空间分布及其特点。③麦珠子属是中国鼠李科植物中唯一呈连续分布且分布最狭窄的属,其他属均为间断分布。苞叶木属、咀签属、勾儿茶属和鼠李属呈现只有主分布区,对刺藤属、雀梅藤属和枳椇属呈主次分布区,小勾儿茶属、蛇藤属、翼核果属、马甲子属、猫乳属和枣属均呈星散分布。  相似文献   

8.
在扫描电子显微镜下,对豆科土儿属(Ap ios)和旋花豆属(Coch lianthus)7个种植物的花粉进行了观察.结果表明,2个属的花粉均为三孔沟,形状为三角球形或球形.土儿属的花粉可划分为2种类型:肉色土儿(A.carnea)的花粉外壁为典型的网状纹饰,其它种的花粉外壁较光滑,具颗粒状或短条纹状纹饰,研究结果不支持土儿属下亚属的划分;肉色土儿花粉外壁的网状纹饰式样可能反映了其在土儿属中处在较进化的位置.土儿属东亚分布种的花粉类型较为多样,原始和进化2种类型并存,表明东亚可能是土儿属的起源地和演化中心.旋花豆属的花粉特征和肉色土儿相似,说明两者之间的亲缘关系可能较近.  相似文献   

9.
东亚特有属——小勾儿茶属的研究   总被引:2,自引:0,他引:2  
钱宏 《植物研究》1988,8(4):119-128
本文对东亚特有属——鼠李科小勾儿茶属(Berchemiella)进行了比较系统地研究, 对该属的建属历史, 形态特征、木材解剖、分类及分布进行了论述。根据该属的木材构造和花粉形态等, 作者赞同中井猛之进将Berchemiella独立为属的观点。该属共有3种1变种, 在我国有2种1变种。毛柄小勾儿茶(B.wilsonii var.pubipetiolata H.Qian, 新变种)为首次描述。  相似文献   

10.
墨脱勾儿茶 新种 图1Berchemiam毢dogensisY.L.ChenetY.F.Du,sp.nov.Fig.1HaecspecieshabituB.flavescenti(Wall.)Brongn.montiumHimalayaesimilis,sedaquaramulis,petiolis,foliissubtusetrhachibusinflorescentiaepuberulisfacilediffert.Frutexscandens;ramuliteretes,viridesvelflavoviri…  相似文献   

11.
Seed micromorphology in 22 species, capsule surface in 28 species and capsule hairs in 20 species of genus Verbascum distributed in Iran were studied using scanning electron microscopy. The seed surface is ridged or alveolate among the studied species. Depth and density of the alveoli or ridges, size of polygonal cells along with arrangement of vesicles on the walls separating the polygonal cells on the seed surface seem to be species-specific in Verbascum. The capsule surface is striate, distinctly or indistinctly, or even smooth in Verbascum. The capsules are rarely glabrous (in V. orientale and V. intricatum), densely covered by branched hairs, or loosely by glandular hairs, depending on species. From the results of this study it is obvious that no correlation exists between the studied species concerning the micromorphological aspects studied here.  相似文献   

12.
A study of seed coat sculpturing in Cordylanthus (Scrophulariaceae—Rhinantheae) using the scanning electron microscope (SEM) shows that seed surface patterns are characteristic and constant for a given species or a group of species. Seeds of 23 species were examined and classified into four types (irregularly crested, deeply reticulate, shallowly reticulate, and irregularly striate) based on differences in the reticulated seed coat. Anatomical studies of sections with the light microscope show that the reticular patterns result from enlargement of the epidermal cells of the integument, followed by formation of characteristic wall patterns through lignification. Seed characters furnish useful data for formulating the taxonomy of Cordylanthus both on the sectional and subsectional level and for the delimitation of certain species. Seed coat morphology offers evidence for including the genus Dicranostegia in Cordylanthus and for maintaining C. hispidus and C. palmatus as separate species. The distinctness of two seed coat types within section Cordylanthus suggests two major phylogenetic lines within this section.  相似文献   

13.
The seed morphology of nine taxa of Juncus from Egypt has been investigated using light and scanning electron microscopy, to determine the importance of seed coat features as taxonomic characters. Macro- and micromorphological characters, including seed shape, color, size, seed appendages, epidermal cell shape, anticlinal boundaries, and outer periclinal cell wall and secondary cell wall sculpture are presented. Four types of seed appendages are recognized: (i) seeds with two appendages; (ii) seeds without appendages; (iii) seeds with minutely a piculate at one end; and (iv) seeds with minutely a piculate at both ends. Two types of anticlinal cell wall boundaries,(i) raised-channeled, straight and (ii) raised, straight or sinuous, and three different shapes of outer periclinal cell wall are described: (i) flat; (ii) concave; and (iii) flat to slightly concave. The secondary sculpture of the cell wall varies from striate to microreticulate or reticulate, and smooth to finely folded. Seed characters provide useful data for formulating the taxonomy of Juncus both on the subgeneric and sectional level. A key for the identification of the investigated taxa based on seed characters is provided.  相似文献   

14.
The seed morphology of nine taxa of Juncus from Egypt has been investigated using light and scanning electron microscopy,to determine the importance of seed coat features as taxonomic characters.Macro-and micromorphological characters,including seed shape,color,size,seed appendages,epidermal cell shape,anticlinal boundaries,and outer periclinal cell wall and secondary cell wall sculpture are presented.Four types of seed appendages are recognized:(i)seeds with two appendages;(ii)seeds without appendages;(iii)seeds with minutely a piculate at one end;and(iv)seeds with minutely a piculate at both ends.Two types of anticlinal cell wall boundaries,(i)raised-channeled,straight and(ii)raised,straight or sinuous,and three different shapes of outer periclinal cell wall are described:(i)flat;(ii)concave;and(iii)flat to slightly concave.The secondary sculpture of the cell wall varies from striate to microreticulate or reticulate,and smooth to finely folded.Seed characters provide useful data for formulating the taxonomy of Juncus both on the subgeneric and sectional level.A key for the identification of the investigated taxa based on seed characters is provided.  相似文献   

15.
Seed and trichome morphology of 13 taxa representing the genus Fagonia in Egypt have been studied using light (LM) and scanning electron microscopy (SEM). Macro‐ and micro‐morphological characters, including seed shape, seed size, seed coat sculpture, trichome density and structure were studied to evaluate their systematic significance. Seed shape and trichome density were found to have only minor taxonomic value, but seed coat sculpturing and trichome structure proved to be valuable characters. These characters offer evidence to combine certain species, e.g. Fagonia kassasii and F. schimperi in F. bruguieri, Fagonia microphylla in F. scabra and Fagonia thebaica in F. arabica. However, F. sinaica, F. tristis, F. boveana and F. isotricha should be maintained as separate species. Generally, the different patterns of seed and trichome morphology are useful in delimitation of species within the genus Fagonia, but they could not be used to characterize groups of related species.  相似文献   

16.
利用光学显微镜和扫描电镜对中国25种4变种绣线菊属(Spiraea L.)植物的种子形态特征进行了研究。结果显示,绣线菊属植物种子外观上呈窄线形至椭圆形,表面有光泽和条纹,种子颜色为红棕色至深褐色;种皮纹饰可分为网纹、复网纹、负网纹和链状网纹4种类型。种子按长宽比的划分方法在一定程度上支持该属传统的组下系的划分;种皮纹饰在种间具有明显的差异,可作为中国绣线菊属植物种的分类依据。本研究为绣线菊属的分类及系统学研究提供了种子形态及种皮微观形态方面的新资料,对进一步完善该属属下分类具有借鉴意义。  相似文献   

17.
18.
Pollen morphology of Chinese 19 species representing 6 genera in the tribe Zizipheae Brongn., Rhamnaceae, was examined under light microscope and scanning electron microscope. The pollen grains oblate or suboblate, rarely subspheroidal. Polar axis 13.1-26.1μm long, equatorial axis 16.5-29.6μm long, 3-colporate, colpus generally narrow, ora lalongate, with two ends connected with the thinned part of exine, forming a H-shape. There are 4 thickenings where colpi and ora pass across, or sometimes the thickenings indistinct, forming a ring. Stratification couspicuous or inconspicuous. Ornamentation of exine obscure, rarely obscurely reticulate under light microscope, but conspicuously fine-reticulate, finely reticulate-foveolate, foveolate, striate-reticulate and shortly striate under scanning electron microscope. A key to the genera based on pollen grains is provided and the general morphology of 6 genera: Paliurus, Ziziphus, Chaydaia, Berchemia, Berchemiella and Rhamnella are described. Based on 4 thickenings and H-shape, pollen grains of the tribe Zizipheae may be divided into two groups: 1. the four thickenings rather larger and conspicuous, or stretched along the colpus in some species, H-shape distinct, e.g. in Berchemiella, Chaydaia and Rhamnella, and 2. the four thickenings smaller, sometimes forming a ring, H-shape more or less conspicuous, e.g. in Berchemia, Paliurus and Ziziphus. With respect to the concept of the genera Berchemiella and Berchemia, there were two different ideas among a number of taxonomists. H. Koidzumi, J. Ohwi and S. Kitamura place the former in Berchemia as a section, but on the contrary, T. Nakai, T. Yamazaki and K. Suessenguth consider Berchemiella and Berchemia as two separate genera. The data from pollen morphology support the latter treatment. Berchemia is closely related to Berchemiella, Chaydaia and Rhamnella in the habit and the floral morphology, but differs from the others by its disc well-developed, eularged and becoming cup-shaped in fruit. They are also different from each other in the characters of pollen grains. T. Yamazaki places the genus Chaydaia in Rhamnella as a section, but according to the pollen morphology to treat Chaydaia and Rhamnella as two independent genera woild be reasonable.  相似文献   

19.
采用扫描电镜技术对蔷薇属25个种及4个月季品种的花粉形态进行观察分析,探讨单叶亚属及蔷薇亚属中的芹叶组、合柱组、桂味组、月季组及月季品种之间的亲缘关系。研究表明:(1)所有被测样品的花粉都为具三孔沟的N3P4C5型单粒花粉,形状包括近球形、长球形及超长球形,其中大部分都为极轴较长的超长球形,以小檗叶蔷薇(P/E=2.29)最长。(2)在疏花蔷薇、托木尔蔷薇以及重瓣黄刺玫中发现有花粉二型现象。(3)被测样品外壁纹饰主要包括条纹、孔穴-条纹及近孔网纹3类,条纹类型主要出现在芹叶组中,而孔穴-条纹类型则为蔷薇属植物较普遍的纹饰。(4)聚类分析表明,小檗叶蔷薇与其它种亲缘较远,被测月季品种与月季组关系较近,芹叶组与合柱组关系较近,桂味组中的弯刺蔷薇与其他蔷薇的纹饰有明显区别,被单独分开。  相似文献   

20.
本文对中国东北牛儿苗科(Geraniaceae)二属(太阳花属Erodium, 老鹳草属(Geranium)计14种(species)1变种(Variety)和1变型(form)植物的种皮亚显微结构(SEM)及种子形态进行了研究.结果表明, 太阳花属与老鹳草属植物无论从种子形状, 长宽比, 还是种皮初级雕纹及次级雕纹形态都表现出明显差异。在老鹤草属下种及种下等级的鉴定和划分上, 种皮微形态及种子形态特征提供了大量有价值的信息。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号