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1.
应用扫描电镜对梣属11种植物次生木质部导管附物纹孔的分布和形态进行了详细的观察,应用Carnoy2.0软件和扫描电子显微镜采集的照片,测定了附物纹孔丰富度指标和纹孔数量特征指标。电镜观察表明,梣属11种研究植物次生木质部导管分子侧壁附物纹孔的分布和形态变化较大,附物纹孔丰富度指标的统计描述进一步证实附物纹孔的分布变化大;3个附物纹孔丰富度指标分别与管间具缘纹孔数量特征指标的逐步回归分析表明,导管侧壁附物纹孔丰富度2个指标,即导管外纹孔口附物频率与导管纹孔腔附物频率随纹孔口面积百分比的增大而增大,推测梣属植物附物纹孔丰富度与纹孔几何构造及数量特征有关。研究认为,附物纹孔在梣属植物稳定存在,是可界定梣属植物的木材解剖性状。  相似文献   

2.
黑龙江槭树属植物导管分子解剖学研究   总被引:9,自引:3,他引:6  
张大维  邢怡  党安志 《植物研究》2007,27(4):408-411
利用扫描电子显微镜,通过管道铸型技术,对黑龙江槭树科(Aceraceae)槭树属(Acer Linn.)中8种植物导管分子的微形态结构进行了比较研究。结果表明:该属植物导管分子长度,除白牛槭 (Acer mandshurica Maxim.)较长外,其余植物种类导管分子长度在133.00~187.50 μm;导管管腔宽度,在17.06~28.00 μm之间;纹孔排列方式以对列式、互列式单独存在,或以两者形式并存;管间纹孔成群分布且大部分呈现一定形状;讨论了导管分子管腔的主要特征及其与生境的关系。  相似文献   

3.
利用扫描电子显微镜对黑龙江苹果亚科5属14种植物导管分子的管腔微形态结构特征进行了比较研究。结果显示:(1)该亚科植物导管分子的管腔长度、宽度及端壁斜度角有较大的差别。(2)孔纹导管在该亚科植物种中均存在,网纹导管和螺纹导管仅见于苹果属和花楸属中。(3)导管分子管壁除苹果属及山楂属中的毛山楂、辽宁山楂外均有螺纹加厚。(4)纹孔的排列方式为互列式、对列式及互列、对列同时存在。(5)在所观察的植物中花楸、山荆子、无毛山楂导管端壁具单穿孔板和梯状穿孔板,其余种的导管端壁仅具单穿孔板。(6)导管纹孔膜残留现象普遍存在。研究表明,导管分子管腔的微形态结构特征,可为该亚科植物的系统演化提供形态学依据;导管分子微形态结构特征与其所处的环境存在一定的适应性。  相似文献   

4.
应用扫描电子显微镜详细观察了红树族4属、10种、1变种植物次生木质部管状分子附物纹孔的分布和形态, 应用Carnoy 2.0软件和扫描电镜下采集的照片, 测定了管间梯状附物纹孔丰富度指标和管间梯状纹孔数量特征指标。结果显示, 红树族植物次生木质部管状分子侧壁具附物纹孔。所观察的植物附物纹孔的分布和形态变化大。附物纹孔丰富度指标与管间梯状纹孔数量特征指标的逐步回归分析表明, 导管侧壁附物纹孔丰富度随纹孔口面积百分比的增大而增大。据此推测, 红树族植物附物纹孔丰富度与纹孔几何构造及数量特征有关。附物纹孔是红树族植物稳定存在的一个木材解剖性状。综合生态-系统演化的观点, 红树族植物具附物纹孔可能是受系统演化关系控制的生态适应结果。  相似文献   

5.
陈树思 《西北植物学报》2006,26(9):1853-1858
运用细胞图象分析系统及显微照相的方法,对余甘子次生木质部导管分子进行观察研究.结果发现,余甘子次生木质部导管分子中存在着许多不同的样式,导管分子大多数具尾;其穿孔板存在着两种类型:(1)两端均为1个单穿孔板;(2)一端为1个单穿孔板另一端为2个单穿孔板;(3)极少数的导管分子具有特殊的内含物;(4)管间纹孔式为互列纹孔式;(5)导管射线间纹孔式为混合型纹孔与横列刻痕状纹孔以及梯状穿孔.  相似文献   

6.
利用光学显微镜和扫描电子显微电镜,以10种茶藨子属植物为研究材料,观察了其导管分子的形态结构。结果显示:(1)所研究的茶藨子属植物导管分子穿孔板为梯状穿孔板,且穿孔板上横隔分布的数量不同,端壁倾斜角度种间变化不大;(2)导管分子纹孔式样为互列式或兼有互列式和对列式,纹孔形状种间存在差异;(3)有的种类导管分子内壁有螺纹加厚或网状凸起。研究表明,不同生境下的茶藨子属植物导管形态与其生态适应性之间有较强的相关性,表现为湿生环境的物种导管较短,直径较宽;旱生环境的物种导管较长,直径较小;中生环境的居中。本文分析了茶藨子属植物导管分子形态特征的生态适应性。  相似文献   

7.
利用光学显微镜和扫描电子显微电镜,以10种茶藨子属植物为研究材料,观察了其导管分子的形态结构。结果显示:(1)所研究的茶藨子属植物导管分子穿孔板为梯状穿孔板,且穿孔板上横隔分布的数量不同,端壁倾斜角度种间变化不大;(2)导管分子纹孔式样为互列式或兼有互列式和对列式,纹孔形状种间存在差异;(3)有的种类导管分子内壁有螺纹加厚或网状凸起。研究表明,不同生境下的茶藨子属植物导管形态与其生态适应性之间有较强的相关性,表现为湿生环境的物种导管较短,直径较宽;旱生环境的物种导管较长,直径较小;中生环境的居中。本文分析了茶藨子属植物导管分子形态特征的生态适应性。  相似文献   

8.
利用扫描电子显微镜(SEM)和树脂铸型法对东北地区10种李属植物导管分子类型、纹孔式、穿孔板类型的微形态结构特征进行了观察,并测量管腔长度、宽度、尾端长度及端壁斜度角的量化数据。结果显示:在不同生境下该属同种植物的导管类型、尾端长度与穿孔板类型较为稳定。所观察的李属植物存在3种导管类型:螺纹、孔纹、网纹导管。除山杏、欧李、东北李3种植物中仅存在网纹与孔纹2种类型的导管外,其余7种植物普遍存在3种类型导管。螺纹加厚在该属导管分子中普遍存在。单穿孔板在李属所观察植物中普遍存在,仅在黑樱桃、毛樱桃和郁李中发现梯状穿孔板。仅在稠李、东北李、郁李及山杏中观察到相对原始的对列—互列同时存在的纹孔式,其余6种均为互列式纹孔式。根据结构分析,认为东北地区10种李属植物中,郁李最为原始,欧李最为进化。同时,发现管腔长度、宽度与端壁面积与生境显著相关。在对尾端长度测量发现,同种植物导管分子的尾端长度在不同生境下长度较为稳定,几乎没有变化,可作为微观植物分类学的分类依据。  相似文献   

9.
中国裸子植物木材具缘纹孔构造类型的研究   总被引:4,自引:0,他引:4  
根据100种中国裸子植物木材(隶属4纲、8目、11科,42属)具缘纹孔构造的研究,提出8种不同具缘纹孔类型:1.苏铁型;2.南洋杉 A 型;3.南洋杉 B 型;4.落羽杉 A 型;5.落羽杉 B 型;6.松木 A 型;7.松木 B 型;8.买麻藤型。A 型是指纹孔室内瘤状层缺乏或罕见,B型则具明显的瘤状层。并对具缘纹孔在系统发育中的变化进行了讨论。  相似文献   

10.
裸子植物木材交叉场纹孔的电镜观察研究   总被引:1,自引:0,他引:1  
本文介绍了扫描电镜和透射电镜下交叉场纹孔在管胞一侧和射线薄壁细胞一侧的形态特征及其变化细节,扫描电镜下管胞胞腔一侧交叉场纹孔口周围形成的光晕,在柳杉(Cryptomeris fortunei Hooibrenk ex Otto et Dietr.)木材中首次看到管胞一侧的交叉场纹孔膜具辐射状排列的微纤丝或束;西藏长叶松(Pinus roxburghii Sarg.)的松木型纹孔膜的边缘具辐射状排列的微纤丝束,此外,尚在臭冷杉[Abies nephrolepis(Trautv.)Maxim.]木材中观察到一种特殊的纹孔口外展的杉木型纹孔,并在冷杉属(Abies)其他种,落叶松属(Laricx)一些种及红皮云杉(Picea Koraiensis Nakai)等木材的交叉场纹孔中也看到。  相似文献   

11.
NAIR, M. N. B. AND MOHAN RAM, H. Y., 1989. Vestured pits and vestured vessel member walls in some Indian dicotyledonous woods. The woods of 144 taxa belonging to 38 families of angiosperms were examined for vestured pits and vestured vessel member walls using scanning electron microscopy. Vestured pits are present in 66 taxa (belonging to ten families) and vestured vessel member walls occur in only six taxa (belonging to three families). In Ehretiaceae and Euphorbiaceae vestures are present only in certain vessel members. In Wrighlia tinctoria , perforation plates containing vestures have been observed in addition to the presence of vestured pits. A classification of vestured pits based on their morphology and distribution is proposed by us. In all the types of vestured pits, vestures are present on the margin of the outer pit aperture or on the pit chamber wall. Occasionally, they are present in the pit canal, on the margin and in the vicinity of the inner pit aperture and rarely over the inner walls of the vessel members. The functions of vestured pits are not clear, although several suggestions are made. Whether or not these structures affect wood processing is not presently understood. It appears that vestured pits and vestured vessel member walls have diagnostic rather than phylogenetic value.  相似文献   

12.
Permineralized gigantopterid stems of Vasovinea tianii Li et Taylor gen. et sp. nov. were collected from the Upper Permian of Guizhou Province, China. They are slender and bear prickles, trichomes, and compound hooks. Internally, the stems have a sparganum cortex, eustele, and secondary xylem. The mesarch protoxylem tracheids have annular to helical thickenings, and metaxylem tracheary elements have scalariform and/or transversely elongated, bordered pits, while those of the secondary xylem have scalariform to circular bordered pits. Importantly, the inner part of the secondary xylem has large vessel elements with foraminate-like perforation plates. The hooks and other morphological and anatomical characteristics are similar to those found in gigantopterids, suggesting that Vasovinea is a member of the Gigantopteridales. The vegetative plant is reconstructed from permineralized stems and Gigantopteris-type leaves based on the anatomical similarities and intimate association. The eustele, secondary xylem, and other features support the placement of the order among the seed plants. Ecologically, Vasovinea is suggested to have been a vine or liana that used compound hooks to climb among the trees in a Permian tropical rain forest. The occurrence of vessels could have been an efficient adaptation to allow the slender stems to conduct sufficient water to the large Gigantopteris-type leaves.  相似文献   

13.
The present paper is devoted to a study of the basic morphological and anatomical characteristics of the endemic family Rhoipteleaceae from China. The fundamental pattern of the morphological and anatomical characteristics of the Rhoipteleaceae is similar to those of the Juglandaceae in wood anatomy, resinous peltate scales, apetaly, bicarpellate pistils, one-seeded fruits and exalbuminous seeds. Whereas Rhoipteleaceae has stipules; perfect flowers with superior 2-loculed ovaries, anatropous ovules and two integuments; vessel elements of the secondary xylem with the scalariform perforation, and 2–8 (18) pores on the oblique plate being observable; vascular rays heterocellular and tricolporate pollen. The above characteristics–at least most of them, agree pretty well with those depicted by Manning in his “Pre-Juglandaceae”. It is quite possible that the Juglandaceae is derived from “Pre-Juglandaceae”by way of the Rhoipteleaceae, as the morphological and anatomical features as indicated above tend to show that the Rhoipteleaceae is more primitive than Juglandaceae. The Rhoipteleaceae was previously considered as related to the Betulaceae or Ulmaceae, a view, which the present study does not prove to be acceptable. Both Takhtajan (1969) and Cronquist (1968) pointed out that the Juglandales, Urticales, Myricales, Fagales are all direct derivatives from the Hamamelidales. However, since the Rhoipteleaceae is simillar to the Betulaceae in wood anatomy and pollen, it seems that there too could have certain relationships between the Rhoipteleaceae and the Betula-ceae in the course of evolution.  相似文献   

14.
The tongue of the striped dolphin, Stenella coeruleoalba, shows a V-shaped row of pits on its posterior dorsum. Their development is described on the basis of macroscopic and light microscopic observations on fetal, young, and adult stages. Four to eight pits occur, most often five in the adult. Anlagen of the pits first protrude as round epithelial thickenings which later increase in diameter and become thin. The circular primordia then sink, and grooves oriented both circularly and radially develop in the walls of the shallow pits thus formed. Pits and grooves deepen with development so that older pits become lined with conical projections. As pits grow further, they become elongated anterolaterally, retaining slit-like openings. Each pit in the adult is 2–8 mm long and about 1 mm wide. The pits are not derived from lingual gland ducts but develop independently. Taste buds resembling those of other mammalian tongues can be found in young dolphins but are few in number and limited to the thin epithelium of the pit projections and to that of the side wall of the pits. They first appear in the late prenatal period but degenerate in the adult. A rich nerve supply is observable in the lamina propria below taste buds in the calf. The pits and their projections in the dolphin correspond to the vallate papillae of other mammals, but whether each projection or a whole pit corresponds to a single vallate papilla is undecided.  相似文献   

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