国产五味子科植物导管分子的比较解剖

对五味子科 2属 1 9种植物导管分子的结构进行了比较观察。结果表明 :2属均以具缘纹孔导管为主 ,少有梯纹和螺纹导管 ,南五味子属多数种还有梯孔纹导管 ;2属导管长度和宽度差异很小 ,长 /宽比值有差异 ;根据穿孔板的结构可分为 2种形式 :( 1 )单穿孔板 ,这类穿孔板较普遍存在 ;( 2 )梯形穿孔板 ,发现 2属中的红花五味子 (Schisandrarubriflora)、五味子 (S .chinensis)、翼梗五味子 (S .henryi)、铁箍散 (S .propinquavar.sinensis)和黑老虎 (Kadsuracoccinea) 5种植物的导管分子具有此类穿孔板。其中五味子属中的五味子导管分子只具有梯形穿孔板 ,无单穿孔板 ,但横条较少 ,多为 2～ 3条。     

细枝木麻黄导管分子及穿孔板解剖学研究

运用细胞图象分析系统和显微照相的方法对细枝木麻黄(CasuarinacunninghamianaMiq.)次生木质部导管分子进行了观察研究。细枝木麻黄次生木质部导管分子有3种类型,即两端具尾导管、一端具尾导管和无尾导管。导管分子穿孔板有4种类型:两端均为梯状穿孔板、一端为单穿孔板,另一端为梯状穿孔板、两端均为单穿孔板、一梯状穿孔板与一单穿孔板位于同一端壁两侧相互对应以及一些过渡类型穿孔板。根据观察结果,分析了各类型穿孔板之间的演化关系。     

黄三七( 毛茛科) 茎次生木质部导管穿孔板的研究*

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。     

基于不同方法的毛茛族(毛茛科)导管穿孔板比较研究

导管分子的演化与植物的进化相关联.毛茛科是联系基部被子植物和核心真双子叶植物的关键类群,对其导管穿孔板的研究具有重要的系统学意义.为研究毛茛科毛茛族不同属植物导管穿孔板类型及其与环境的相关性,该文利用新的扫描电子显微镜和半薄切片技术,对该族7属8种植物次生木质部导管状分子进行了比较观察.结果表明:木质部管状分子以单穿孔...     

东北刺人参茎次生木质部结构植物学研究

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。     

The effect of vessel element structure on element conductivity

Summary A number of structural variables influence the conductivity of simple and scalariform perforation plates, and of vessel lumina. Using a previously developed computer model, the effects on conductivity of over 8,000 permutations of different lumen radii, perforation plate angles, perforation plate rim widths, scalariform slit pore heights, and scalariform bar thicknesses are considered. By taking advantage of basic patterns of similarity in the data, and by using scaling techniques, it has proved possible to calculate a series of factors which may be used to predict the conductivity of a vessel element or perforation plate of known dimensions. A number of previous workers have sought relationships between element structure and evolutionary or adaptive trends. Some important variables have been ignored in these studies in the past.     

慈姑不定根中导管分子的观察

慈姑导管仅在根中出现。根的后生木质部中央导管由顶端平截、单穿孔的网纹导管分子连接组成;周围较小的导管分子和管胞有从梯纹管胞向导管分子演化的各种过渡类型;有一至多个梯形穿孔或单穿孔发生在导管分子的端壁或侧壁,并有分枝型导管分子存在,特别在根与主茎连接处尤为明显。管胞亦有分枝与不分枝的类型。     

余甘子次生木质部导管分子观察研究

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.     

蜈蚣草导管分子的观察

对蜈蚣草(Pteris vittata)叶轴中导管分子进行了观察。结果表明,其导管分子十分细长,均具长、且十分倾斜的梯状穿孔板,穿孔没有纹孔膜的残余,与侧壁上的梯纹纹孔有着明显的差异。     

Resistances to fluid flow of model xylem vessels with simple and scalariform perforation plates

The resistances of xylem vessel walls and perforation plates has been investigated using 18 large-scale physical models made of plastic tubing into which scale models of plates were inserted. Flow of water through vessels was modelled using glycerol instead of water to keep the Reynolds number below 0.1. The technique proved easy, cheap and reliable.Results showed that perforation plate resistance is low compared with the resistance of the walls, whatever the plate morphology; plates only provided 0.6-18.6% extra resistance. Simple plates provided less resistance than scalariform plates, but because they are arranged closer together in vessels, resistance values (1.7-5.1%) overlap with those of scalariform plates. The resistance of scalariform plates varied in a systematic way with their morphology. For a given plate angle, increasing the number of bars increased resistance. For a given bar number, increasing the angle of the plate to the vessel axis also increased the resistance. However, for a given gap between bars, increasing the angle of the plate to the vessel axis decreased resistance. These results are discussed in the light of theories about the function of perforation plates.Keywords: Flow, xylem vessel, perforation plate, models.      

Distribution of scalariform and simple perforation plates within the vessel network in secondary xylem of Araliaceae and its implications for wood evolution

The distribution of scalariform and simple perforation plates along vessels in Arthrophyllum otopyrenum, Meryta tenuifolia, and Polyscias multijuga (Araliaceae) is examined. In all three species, most vessels bear simple perforation plates only, but the combination of simple and scalariform perforation plates in variable ratios also occurs. Aggregated arrangement of scalariform perforation plates along the vessels was statistically confirmed in some vessel portions. The scalariform perforation plates occur mostly in narrow vessels that are grouped in multiples. Within the clade represented by Polyscias and Arthrophyllum, the evolutionary transition from scalariform to simple perforation plates is realized as the gradual elimination of vessels or vessel portions with scalariform perforation plates, but is not accompanied by a gradual decrease of the number of bars per perforation plate. The narrow vessels that are grouped in vessel multiples are likely to retain the ability to develop scalariform plates, which could promote the evolution from simple to scalariform perforation plates as is the case within Meryta.     

台湾青枣导管分子及其穿孔板研究

运用细胞图象分析系统及显微照相的方法对台湾青枣Z iziphus mauritiana次生木质部导管分子进行了观察研究。在台湾青枣的次生木质部导管分子中存在着许多不同的样式,并且导管分子穿孔板存在着3种类型:两端均为一个单穿孔板;一端为一个单穿孔板,另一端为梯状穿孔板;具纤毛的单穿孔板。分别对其进行了描述,并从导管分子个体发育与系统发育的角度进行了讨论,认为3种类型的穿孔板为导管分子穿孔板的系统演化提供了新的证据。     

蜈蚣草导管分子的观察

对蜈蚣草(Pteris vittata)叶轴中导管分子进行了观察。结果表明,其导管分子十分细长,均具长、且十分倾斜的梯状穿孔板,穿孔没有纹孔膜的残余,与侧壁上的梯纹纹孔有着明显的差异。     

领春木茎次生木质部中导管穿孔板的变异

领春木Euptelea pleiosperma Hook. f. &; Thoms.隶属领春木科Eupteleaceae。该科为东亚特有的单型科,其系统位置一直颇有争议。本文对中国产领春木茎次生木质部中导管穿孔板的变异进行了观察,以期为它的系统位置提供进一步的解剖学证据。结果表明,领春木茎次生木质部中包括无明显穿孔板的管胞状导管和典型的导管两种类型。在无明显穿孔板的导管中,穿孔中的纹孔膜全部或部分消失,但穿孔无规则排列或聚集,不形成具典型的形态特征的穿孔板;在典型的导管中,穿孔板形态变异较大,包括几个类型:网状穿孔板(含麻黄式穿孔板)、网状和梯状混合型穿孔板、梯状穿孔板、梯状穿孔板向单穿孔板的过渡。在上述导管穿孔板类型中,只有梯状穿孔板的穿孔中可以观察到纹孔膜的残余。在领春木次生木质部中也观察到了端壁多穿孔板及侧壁穿孔板。根据观察结果,我们认为领春木次生木质部导管穿孔板的许多特征说明该科可能处于毛茛目中比较原始的系统位置。     

黄三七(毛茛科)茎次生木质部导管穿孔板的研究

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。     

基质盐度对木榄叶柄导管分子形态特征的影响

对温室中培养在不同盐度下一年生木榄[Bruginera gyninorrhiza(L.)Poil]植株上成熟叶的叶柄离析研究的结果表明:1)木榄叶柄导管分子以梯纹导管为主,其次为螺纹导管及它们之间的过渡类型;随着盐度的升高,螺纹导管及它们之间的过渡类型有增多的趋势;2)而叶柄长度,梯纹导管分子的直径、长度及两端梯状穿孔板的横隔条数都与盐度呈抛物线关系,而它们的最大位出现在20‰-30‰,范围内;3)培养于盐度10‰的海水中的木榄叶柄中导管分子一端有出现两个朝向不同的梯状穿孔板现象;4)在低盐条件下,随着基质盐度的提高,导管分子的形态朝着有利于加快水分运输的方向发展,而在高盐环境下,导管分子的形态朝着增加水分运输的安全性方向发展。讨论了叶柄导管分子解剖学特征的适应意义。     

基质盐度对木榄叶柄导管分子形态特征的影响

对温室中培养在不同盐度下一年生木榄[Bruguiera gymnorrhiza(L.)Poil]植株上成熟叶的叶柄离析研究的结果表明：1）木榄叶柄导管分子以梯纹导管为主,其次为螺纹导管及它们之间的过渡类型;随着盐度的升高,螺纹导管及它们之间的过渡类型有增多的趋势;2）而叶柄长度,梯纹导管分子的直径、长度及两端梯状穿孔板的横隔条数都与盐度呈抛物线关系,而它们的最大值出现在20‰-30‰范围内;3）培养于盐度10‰的海水中的木榄叶柄中导管分子一端有出现两个朝向不同的梯状穿孔板现象;4）在低盐条件下,随着基质盐度的提高,导管分子的形态朝着有利于加快水分运输的方向发展,而在高盐环境下,导管分子的形态朝着增加水分运输的安全性方向发展。讨论了叶柄导管分子解剖学特征的适应意义。     

鹅掌楸属(木兰科)次生木质部导管穿孔板的比较研究

利用扫描电子显微镜对鹅掌楸属仅存的2个自然种鹅掌楸和北美鹅掌楸的次生木质部导管穿孔板特征进行了详细的研究。结果显示,鹅掌楸属的2个种均以梯状穿孔板为主,同时存在网状-梯状混合穿孔板。鹅掌楸和北美鹅掌楸的导管穿孔板具有明显差异:(1)鹅掌楸具网状穿孔板,而北美鹅掌楸没有观察到;(2)北美鹅掌楸具单穿孔板,而鹅掌楸在该实验中未发现;(3)北美鹅掌楸具有横隔较粗的梯状穿孔板且横隔数目较多;(4)鹅掌楸的导管穿孔板多数横隔较少;(5)北美鹅掌楸的穿孔板倾斜角度较大;(6)北美鹅掌楸具麻黄式穿孔板的存在,且有纹孔膜残留存在。研究认为,北美鹅掌楸导管分子穿孔板分化较鹅掌楸更为剧烈。     

10 种茶藨子属植物导管分子形态特征及其生态适应性比较研究简

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。     

Single‐vessel flow measurements indicate scalariform perforation plates confer higher flow resistance than previously estimated

During vessel evolution in angiosperms, scalariform perforation plates with many slit‐like openings transformed into simple plates with a single circular opening. The transition is hypothesized to have resulted from selection for decreased hydraulic resistance. Previously, additional resistivity of scalariform plates was estimated to be small – generally 10% or less above lumen resistivity – based on numerical and physical models. Here, using the single‐vessel technique, we directly measured the hydraulic resistance of individual xylem vessels. The resistivity of simple‐plated lumens was not significantly different from the Hagen–Poiseuille (HP) prediction (+6 ± 3.3% mean deviation). In the 13 scalariform‐plated species measured, plate resistivity averaged 99 ± 13.7% higher than HP lumen resistivity. Scalariform species also showed higher resistivity than simple species at the whole vessel (+340%) and sapwood (+580%) levels. The strongest predictor of scalariform plate resistance was vessel diameter (r² = 0.84), followed by plate angle (r² = 0.60). An equation based on laminar flow through periodic slits predicted single‐vessel measurements reasonably well (r² = 0.79) and indicated that Baileyan trends in scalariform plate evolution maintain an approximate balance between lumen and plate resistances. In summary, we found scalariform plates of diverse morphology essentially double lumen flow resistance, impeding xylem flow much more than previously estimated.