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东北刺人参茎次生木质部结构植物学研究 总被引:2,自引:0,他引:2
东北刺人参为五加科植物,本文对其茎次生木质部进行结构植物学研究,发现其为环孔材,射线为异形Ⅱ型。在离析材料中,发现其导管分子穿孔板有单穿孔板和梯状穿孔板2种。具不同穿孔板的导管分子可分为8种。还有维管管胞、纤维管胞和韧型木纤维。8种导管分子是只有中央具1个单穿孔的导管;中央有2个穿孔的导管,其中一个孔是单穿孔,另一个是梯状穿孔;一端是梯状穿孔板,另一端为孔纹增厚的导管;一端是单穿孔。另一端是孔纹增厚的导管;一端为单穿孔板。另一端为梯状穿孔板的导管;两端都是梯状穿孔板的导管;侧壁具有3个穿孔的导管;两端都具单穿孔的导管。在东北刺人参的个体发育中重演了系统发育过程中导管分子穿孔板的演化过程。 相似文献
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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
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对东北雷公藤苇次生木质部结构及其与卫矛科其它属进行比较研究,为东北雷公藤生药鉴定提供了理论依据。结果表明:东北雷公藤茎次生木质部早晚材导管分子大小差异极大.为环孔材;导管分子穿孔板均为单穿孔板;异型Ⅱ-b射线;纤维管胞具螺纹增厚;具分隔木纤维。 相似文献
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本文报道连香树木材解剖和扫描电镜研究结果,连香树木材特征较为原始,具导管和管胞,导管端壁斜、梯状穿孔板、具有超出穿孔板的三生螺旋加厚,管胞为原始的梯纹管胞,木纤维壁上具裂隙状纹孔,木薄壁组织离管型,星散状分布,木射线异型。 相似文献
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不同纬度对鹅掌楸次生木质部结构的影响 总被引:1,自引:0,他引:1
对生长在北纬23至32度的鹅掌楸〖WTBX〗(Liriodendron chinense〖WTBZ〗 Sarg.)的次生木质部进行了比较解剖学研究。观察的特征有:导管分子的长度、直径、壁厚、梯状穿孔板横闩的数目;导管密度、纤维长度、直径、壁厚;射线的高度、宽度,单列射线的比例,射线的密度等。结果表明,随着纬度的增加,导管分子变短变细,壁变薄,梯状穿孔板的横闩数目减少;纤维也变短变细,壁变薄;木射线变矮变窄,单列射线的比例和射线密度增加。 相似文献
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花楸(Sorbus pohuashanensis)导管分子穿孔板的类型及演化 总被引:12,自引:2,他引:10
对花楸茎次生木质部进行离析研究,发现其导管穿孔板有两种类型,即网状穿孔板和单穿孔板,并且还有5种过渡类型,具不同类型穿孔板的导管分子有3种类型,即两端均为网状穿孔板的导管分子;一端为网状穿孔板,另一端为单穿孔板的导管分子;两端的均为单穿孔板的导管分子,在花楸个体发育过程中穿孔板类型的演化重演了系统发育过程中导管网状穿孔板演化成单穿孔板的过程。 相似文献
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凹叶厚朴细弱枝与粗壮枝导管分子的比较研究 总被引:5,自引:0,他引:5
对凹叶厚朴粗壮枝和细弱枝的次生木质部进行离析研究,发现其导管穿孔板有两种类型,即单穿孔板和梯状穿孔板。在细弱枝中,具不同类型穿孔板的导管分子有八种类型,即一端为单穿孔板的导管分子,另一端为梯状穿孔板的导管分子;只有一端为单穿孔板的导管分子;只有一端为梯状穿孔板的导管分子;两端均为单穿孔板的导管分子;两端均为梯状穿孔板的导管分子;具三个单穿孔板的导管分子;两端具单穿孔板的导管分子,中间具多个梯状穿孔板的导管分子;具多个梯状穿孔板的导管分子。粗壮枝除了无具多个梯状穿孔板的导管分子外,其它细弱枝的导管分子的类型都具有。细弱枝的导管分子宽而长,粗壮枝导管分子窄而短。 相似文献
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Frank H. Smith 《American journal of botany》1967,54(10):1215-1223
Salivary secretions injected into the cortex or outer phloem by Adelges piceae (balsam woolly aphid) feeding on Abies grandis induce the production of wood that is in some respects similar to compression wood. Cambial activity was analyzed by examination of serial tangential sections through an annual ring in the xylem produced before infestation occurred and compared with similar sections from a ring produced after infestation. Growth after infestation was characterized by increased periclinal and anticlinal divisions of fusiform initials, increased production of new ray initials from fusiform initials and from anticlinal divisions of existing ray initials, and decline of numerous fusiform initials and termination of many tiers by maturation. This results in increased frequency of ray fusion and separation by decline or intrusion of adjacent fusiform initials. There was a marked increase in size and number of rays and number of parenchyma strands both of which also distinguish aphid-affected wood from compression wood with which it frequently has been compared. 相似文献
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The relationship of selected wood anatomical characters of NepaleseRhododendron with stem diameter, plant height, altitude, and plant form was investigated. We studied one to three specimens each of 26
species: five species each of trees and subtrees I, three species of subtrees II, and 13 species of shrubs. Multiple regression
analysis and actual distribution of character values show that pore characters and multiseriate ray ratio have a stronger
correlation with stem diameter than altitude; that pore density, vessel element length, fiber-tracheid length, and multiseriate
ray density and width are equally related to altitude and stem diameter, or to altitude and plant height; and that bar number,
and multiseriate ray area and height have a stronger connection with altitude. Among the characters, average pore area is
most strongly correlated with stem diameter and increases exponentially as diameter increases. For wood structure of NepaleseRhododendron, 17 to 63 % of the variation is affected by non-anatomical factors. The general trends in wood structure of NepaleseRhododendron show that trees and subtrees form one continuous unit whereas shrubs form another that often has wider ranges of variation. 相似文献
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Radially oriented ray tissue is important for regulating radial strength of wood. The present study was undertaken in order to assess whether radial rays influence ring shake occurrence in chestnut wood (Castanea sativa Mill.), a species very prone to ring shake. Ray volume fraction was measured on tangential samples from two sets of wood discs, either with or without ring shake, collected from three coppice stands in the southern part of the Swiss Alps. Our data indicate that ring shaken trees tend to exhibit higher ray volume than unshaken ones. This rather unexpected finding could be partly explained if biomechanical processes that control and determine the inner architecture of the tree are considered. 相似文献
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Wood anatomy of Eucalyptus globulus Labill. under different habitats was comparatively studied under light and scanning electron microscope. According to the eleven major quantitative perimeters of wood characteristics of E. globulus viz: vessel frequency, percentage of solitary vessels, vessel diameter, vessel member length; tracheid length and diameter; fibre tracheid length and diameter; libriform fibre length; ray frequency and ray height, the plants under different habitats have been made a comparison. The results showed that growth ring was indistinct, and there was a positive correlation between the quantitative characters of most wood constituent members were positively correlated with the latitude except for some of vessel frequency decreased. The decrease in effects of annual rainfall on the structure of the wood of E. glotrulus were evaluated. 相似文献
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There are two types of sites where aggregate rays in Quercusithaburensis Decne. and Q. calliprinos Webb do not occur naturallyin the tree: branch junctions and small ridges of wood. Partialgirdling of Quercus trunks resulted in the dispersion of aggregaterays which diffused into numerous simple rays. The breakup ofaggregate rays following partial girdling is not a typical woundresponse since wounding is known to stimulate ray enlargement.The disaggregation of the huge rays reflects changes in therelationship between axial and radial signal flows. Aggregate rays, Quercus ithaburensis Decne., Quercus calliprinos Webb, ray differentiation, wood formation, xylem anatomy 相似文献
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不同生境下蓝桉的木材解剖研究 总被引:9,自引:0,他引:9
用光镜及扫描电镜对不同生境下的蓝桉(Eucalyptusglobulus Labill.)木材结构进行了解剖学观察,描述了木材结构特征。以蓝桉木材的11 个主要特征——导管频率、单孔率、导管直径、导管分子长度、管胞长度和直径、纤维管胞长度和直径、纤维长度、射线频率和高度为指标,对生长在不同生境下的蓝桉进行比较发现:随着纬度的增加,生长轮变化不明显;木材中大部分组成分子的数量特征,除导管频率有降低趋势外均与纬度成正相关。评述了年降雨量对蓝桉木材结构的影响 相似文献
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Wood structure of three species i.e. Larix chinensis Beissn., Alnus sibirica Fisch. and Quercus mongolica Fisch. of normal and dwarf trees were comparatively studied. The age variation of width of annual rings and size of tracheary elements in these trees follows their own regularities respectively during the course of ontogenesis. In normal, as trees grow, the width of annual rings increases gradually, reaches maximum, then declines in subsequence; while the size of tracheary elements exhibits a crescendo increment, and remains constant after reaching maximum. These trends were not affected by the change of enviromental conditions in which the trees grow. However, the width of annual rings and size of tracheary elements of dwarf trees which grow in adverse circumstances are respectively narrower and smaller than those of normal trees. Further, in dwarf tree of L. chinensis (coniferous wood); the diameter of bordered pits on tracheids of early wood decreases, ray height is lower and ray frequence is higher. In dwarf tree of A. sibirica (diffuse porous wood), vessel frequence increases and the number of bars per perforation decreases. The quatitative features of wood structure of dwarf trees, as compared with those of normal trees, showed more variations; whereas, their own qualitative features of wood structure remain constant. These findings might indicate that modifications of wood structure responsing directly to change of enviromental conditions are usually only qualitative. 相似文献