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1.
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   

2.
Stems of four species of the Australian family Tremandraceae furnished sufficient material for analysis of wood anatomy. Presence of simple perforation plates on vessel elements, occurrence of libriform fibers (some septate), tendency toward vasicentric parenchyma, presence of crystalliferous axial parenchyma strands, presence of crystals singly in ray cells, and occurrence of amorphous deposits in parenchyma are all features in which Tremandraceae resemble Pittosporaceae. Wood anatomy tends to support a “rosoid” rather than a sapindalean, rutalean, or polygalalean affinity for Tremandraceae, although wood is only a preliminary indicator. By the use of numerical indices as well as such indicators as helical thickening and presence of vascular tracheids, wood of Tremandraceae is shown to be highly xeromorphic. The genus Tremandra may represent a secondary entrant into wet forests of southwestern Australia; it clearly is not relict from mesic ancestry.  相似文献   

3.
Wood samples of 49 specimens representing 31 species and 11 genera of woody balsaminoids, i.e., Balsaminaceae, Marcgraviaceae, Pellicieraceae, and Tetrameristaceae, were investigated using light microscopy and scanning electron microscopy. The wood structure of Marcgraviaceae, Pellicieraceae, and Tetrameristaceae is characterized by radial vessel multiples with simple perforation plates, alternate vessel pitting, apotracheal and paratracheal parenchyma, septate libriform fibers, and the presence of raphides in ray cells. Tetrameristaceae and Pellicieraceae are found to be closely related based on the occurrence of unilaterally compound vessel-ray pitting and multiseriate rays with long uniseriate ends. The narrow rays in Pelliciera are characteristic of this genus, but a broader concept of Tetrameristaceae including Pelliciera is favored. Within Marcgraviaceae, wide rays (more than five-seriate) are typical of the genus Marcgravia. Furthermore, there is evidence that the impact of altitude and habit plays an important role in the wood structure of this family. The wood structure of Balsaminaceae cannot be compared systematically with other balsaminoids because of their secondary woodiness. Balsaminaceae wood strongly differs due to the presence of exclusively upright ray cells in Impatiens niamniamensis, the absence of rays in Impatiens arguta, and the occurrence of several additional paedomorphic features in both species.  相似文献   

4.
Wood anatomy ofCoriaria was surveyed to clarify generic features on the basis of 14 species collected from various regions of the World to cover the whole range of geographic distribution and habitual variation. Wood anatomy ofcoriaria is considerably uniform, and the species share a combination of the following features: 1) pores are thin-walled, polygonal in outline and mostly in multiples; 2) vessel elements and libriform fibers are very short; 3) perforation plates are exclusively simple; 4) intervessel pits are alternate; 5) vascular tracheids are present; 6) wood parenchyma is vasicentric and sometimes confluent; 7) rays are heterogeneous and large. Its species differ in several characters, such as distinctness of growth rings, pore size, pore patterns, type and abundance of wood parenchyma, and distinctness of storied structure. Comparisons among species indicate that the species of the Northern Hemisphere show a tendency toward having semi-ring porosity, while those of the Southern and Western Hemisphere have diffuse porosity. The other infrageneric variations appear to be related to different habits of the species rather than to geographic distribution. Small trees mostly have confluent and vasicentric parenchyma composed of fusiform cells and distinctly storied tissues, while shrubs and herbs have less abundant parenchyma which is vasicentric and comprises strands of two to four cells and indistinctly storied tissues.  相似文献   

5.
Four life forms (habits) are identified in the 13 species of Moringa (bottle trees, sarcorhizal trees, slender trees, and tuberous shrubs) which are examined for wood anatomical correlations with habit, ecology, and systematic. Wood anatomy is similar within habit classes except for the sarcorhizal trees. The four bottle tree species and M. arborea (one of the sarcorhizal trees) are characterized by bands of confluent paratracheal parenchyma alternating with bands of libriform fibres, some of which may be parenchyma-like. The other sarcorhizal tree, M. ruspoliana , is characterized by alternating bands of parenchyma-like and long, slender libriform fibres. Root secondary xylem of all these species is characterized by bands of parenchyma and fibres. Slender trees do not show bands of fibres of different shapes and have fibrous roots with less parenchyma than the other species. Tuberous shrubs have stems mostly composed of long, slender fibres and large underground tubers mostly composed of parenchyma. Quantitative trends between ecologically different localities include wider vessel elements and higher conductive area in moister localities. Wood anatomy provides characters that are of potential phylogenetic utility at a variety of levels of relationship. Based on wood anatomy and geography, the most likely sister taxon to Moringa is Cylicomorpha (Caricaceae).  相似文献   

6.
Quantitative and qualitative data are presented for woods of 30 species of woody Polygonaceae. Wood features that ally Polygonaceae with Plumbaginaceae include nonbordered perforation plates, storeying in narrow vessels and axial parenchyma, septate or nucleate fibres, vasicentric parenchyma, pith bundles that undergo secondary growth, silica bodies, and ability to form successive cambia. These features are consistent with pairing of Plumbaginaceae and Polygonaceae as sister families. Wood features that ally Polygonaceae with Rhabdodendraceae include nonbordered perforation plates, presence of vestured pits in vessels, presence of silica bodies and dark-staining compounds in ray cells, and ability to form successive cambia. Of the features listed above, nonbordered perforation plates and ability to form successive cambia may be symplesiomorphies basic to Caryophyllales sensu lato . The other features are more likely to be synapomorphies. Wood data thus support molecular cladograms that show the three families near the base of Caryophyllales s.l. Chambered crystals are common to three genera of the family and may indicate relationship. Ray histology suggests secondary woodiness in Antigonon, Atraphaxis, Bilderdykia, Dedeckera, Eriogonum, Harfordia, Muehlenbeckia, Polygonum , and Rumex . Other genera of the family show little or no evidence of secondary woodiness. Molecular data are needed to confirm this interpretation and to clarify the controversial systematic groupings within the family proposed by various authors. Vessel features of Polygonaceae (lumen diameter, element length, density, degree of grouping) show an extraordinary range from xeromorphy to mesomorphy, indicating that wood has played a key role in ecological and habital shifts within the family; the diversity in ecology and habit are correlated with quantitative wood data.  © 2003 The Linnean Society of London. Botanical Journal of the Linnean Society , 2003, 141 , 25−51.  相似文献   

7.
Definitions of character states in woods are softer than generally assumed, and more complex for workers to interpret. Only by a constant effort to transcend the limitations of glossaries can a more than partial understanding of wood anatomy and its evolution be achieved. The need for such an effort is most evident in a major group with sufficient wood diversity to demonstrate numerous problems in wood anatomical features. Caryophyllales s.l., with approximately 12 000 species, are such a group. Paradoxically, Caryophyllales offer many more interpretive problems than other ‘typically woody’ eudicot clades of comparable size: a wider range of wood structural patterns is represented in the order. An account of character expression diversity is presented for major wood characters of Caryophyllales. These characters include successive cambia (more extensively represented in Caryophyllales than elsewhere in angiosperms); vessel element perforation plates (non‐bordered and bordered, with and without constrictions); lateral wall pitting of vessels (notably pseudoscalariform patterns); vesturing and sculpturing on vessel walls; grouping of vessels; nature of tracheids and fibre‐tracheids, storying in libriform fibres, types of axial parenchyma, ray anatomy and shifts in ray ontogeny; juvenilism in rays; raylessness; occurrence of idioblasts; occurrence of a new cell type (ancistrocladan cells); correlations of raylessness with scattered bundle occurrence and other anatomical discoveries newly described and/or understood through the use of scanning electron microscopy and light microscopy. This study goes beyond summarizing or reportage and attempts interpretations in terms of shifts in degrees of juvenilism, diversification in habit, ecological occupancy strategies (with special attention to succulence) and phylogenetic change. Phylogenetic change in wood anatomy is held to be best interpreted when accompanied by an understanding of wood ontogeny, species ecology, species habit and taxonomic context. Wood anatomy of Caryophyllales demonstrates problems inherent in binary character definitions, mapping of morphological characters onto DNA‐based trees and attempts to analyse wood structure without taking into account ecological and habital features. The difficulties of bridging wood anatomy with physiology and ecology are briefly reviewed. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164 , 342–393.  相似文献   

8.
Results of a comparative wood anatomical survey of the American frankenias are presented. The eleven species examined are woody perennials occurring almost exclusively in arid and semiarid regions and on saline and gypseous soils. The secondary xylem of all species is highly specialized and is characterized by libriform fibers, vessel elements with simple perforation plates, and the absence of rays. Axial elements of all species are quite small. A number of unusual features, e.g., anomalous secondary growth and formation of interxylary cork, were observed in some species. Nonfibrous woods have evolved independently in two species of reduced stature and contrast markedly with the highly fibrous woods of most species. Woods of the American frankenias are compared with those of the Tamaricaceae. The systematic and evolutionary implications of interspecific variation in both qualitative and quantitative features are discussed. There is a general tendency for dimensions of the axial wood elements to be positively associated and to decrease with decreasing plant height. In general, differences in wood anatomy more strongly reflect differences in plant growth form and size than phylogeny.  相似文献   

9.
Four collections of three species ofTrimenia and one collection ofPiptocalyx were studied; early-formed and later-formed wood was analyzed for oneTrimenia. Liquid-preserved material permitted analysis of mucilage and starch storage in wood ofT. neocaledonica andP. moorei. BecausePiptocalyx is scandent whereasTrimenia is arborescent, wood differences relative to evolution of a climbing habit could be examined.Piptocalyx contrasts withTrimenia in having wider vessels, more numerous per mm2, resulting in a conductive area five times greater per unit area than that of theTrimenia woods averaged.Piptocalyx has appreciably fewer bars per perforation plate and thus much greater conductive area per perforation plate than have the species ofTrimenia. Rays inPiptocalyx are much taller and wider than those ofTrimenia. Wood ofTrimeniaceae is highly primitive in its scalariform perforation plates, scalariform lateral wall pitting on vessels, relatively long vessels elements, and heterocellular rays. Imperforate tracheary elements are septate nucleate fibertracheids (or even libriform fibers) rather than tracheids, but loss of borders on pits (and thus lowered conductive function of the imperforate tracheary elements) can be explained by the development of these elements into starchstoring cells. Some fiber-tracheids inT. neocaledonica are enlarged mucilagecontaining cells. Details of vessel structure inTrimeniaceae are similar to those ofMonimiaceae (s. s.), but similarity to some other lauralean (annonalean) families may be found: in mucilage presence,Trimeniaceae resembleLauraceae rather thanMonimiaceae. Wood ofTrimeniaceae may be regarded as highly mesomorphic, corresponding to the moist habitats in which all of the species occur.  相似文献   

10.
Wood anatomy was examined in 16 species of Meryta (a genus of c . 35 species) and bark anatomy was studied in 12 species. All but two of these taxa form an assemblage corresponding to the Northern Arc clade, one of two major groups identified by a recent molecular phylogenetic study. M. sinclairii and M. tenuifolia (corresponding to the New Zealand/Fiji clade) differ distinctly by having more numerous simple perforation plates, multiseriate rays with few marginal rows, and the absence of sclerified cells in collapsed secondary phloem, a bark feature that has not yet been found elsewhere in Araliaceae. The increase in abundance of simple perforation plates in the wood of these two species is not accompanied by a decrease in the number of bars on scalariform perforation plates. The wood structure of Meryta bears a strong resemblance to members of the Pacific Schefflera clade, sharing similar ranges of variation of several features. Bark characters, such as the diameter of the cortical secretory canals, the types of crystal in cortical cells, the types of axial parenchyma cell in collapsed secondary phloem, and the presence of sheath cells by phloem rays, appear to be of diagnostic value for some species of Meryta .  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 363–379.  相似文献   

11.
Wood and stem anatomy is studied for seven species of six genera (root anatomy also reported for one species) of Amaranthaceae s.s. Quantitative data on vessels correlate closely with relative xeromorphy of respective species, agreeing with values reported for dicotyledons without successive cambia in comparable habitats. Libriform fibre abundance increases and vessel diameter decreases as stems and roots of the annual Amaranthus caudatus mature. Long, thick-walled fibres in Bosea yervamora may be related to the upright nature of elongate semi-climbing stems. Non-bordered or minutely bordered perforation plates characterize Amaranthaceae, as they do most other Caryophyllales. Amaranthaceae have idioblastic cells containing druses, rhomboidal crystals or crystal sand: these forms intergrade and seem closely related. Rays are present in secondary xylem of the Amaranthaceae studied. Cells intermediate between ray cells and libriform fibres occur in Charpentiera elliptica . Degrees of diversity in rays and reports of raylessness in Amaranthaceae induce discussion of definition and identification of rays in dicotyledons; some sources recognize both rays and radial plates of conjunctive tissue in Amaranthaceae. The action of successive cambia is described: lateral meristem periclinal divisions produce secondary cortex externally, conjunctive tissue internally and yield vascular cambia as well. Vascular cambia produce secondary phloem and secondary xylem, in both ray and fascicular zones, as in a dicotyledon with a single cambium. Identification of meristem activity and appreciation of varied ray manifestations are essential in understanding the ontogeny of stems in Amaranthaceae (which have recently been united with Chenopodiaceae).  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 1–19.  相似文献   

12.
The wood anatomy of Coccoloba cozumelensis Hemsl., Coccoloba spicata Lundell, Gymnanthes lucida Sw., Blomia cupanioides Miranda, Canella winterana (L.) Gaertn., Aspidosperma megalocarpon Müell Arg. and Ehretia tinifolia L., is described. One tree per species was collected in the tropical rain forest of Quintana Roo, Mexico. Their wood has important traditional uses in furniture, tools, rural buildings, posts, fences, railroads and firewood. Macroscopic and microscopic characteristics were described and measured in wood samples, permanent slides and macerated material. These species have diffuse porosity, alternate vessel pits, simple perforation plates, numerous and small rays; libriform fibres are common, as well as ergastic material in gum forms, calcium carbonate and silica crystals. These characteristics explain aesthetical, weight, hardness and resistance (to mechanical and biological damage) characters that fit traditional use by the Maya.  相似文献   

13.
对盐肤木茎进行木材解剖学研究,发现其导管分子穿孔板为单穿孔板。根据穿孔板在导管分子上的位置和数量,导管分子可分为4种类型,即只有一个单穿孔板,位于导管中央,且具有螺纹增厚;两端均为单穿孔板,且具螺纹增厚;两端均为单穿孔板,且具有孔纹增厚;具三个单穿孔板,一端有2个,另一端有1个,且具螺纹增厚。组成细胞中还有分隔木纤维、螺纹管胞。盐肤木为环孔材,射线为异形射线。  相似文献   

14.
Wood anatomy has been investigated from 35 species belonging to the Neotropical clade of the polyphyletic genus Schefflera (Araliaceae), representing three of the five subgroups (Didymopanax, Crepinella and Sciodaphyllum). The species examined are rather uniform in their wood structure, sharing the presence of scalariform and simple perforation plates, septate fibres and scanty paratracheal axial parenchyma. The observed variation in many wood characters showed statistically significant differences relative to latitude, climate and, especially, vegetation types. In particular, the intervessel pits are larger in species from higher latitudes and in seasonally dry habitats than those from lower latitudes and rainforests. Latitudinal and ecological trends in the variation of vessel element lengths, bar numbers on perforation plates, intervessel pit sizes and ray widths may be at least partially explained as effects of adaptation to drier environments in the course of dispersal outside the Amazonian region and diversification in the Atlantic Forest subclade and the Savannic subclade within the Didymopanax group. The occurrence of a granular annulus on the intervessel pit membranes in S. chimantensis and S. sprucei (both of the Crepinella group) is the first record of this feature in Araliaceae. In comparisons of Neotropical Schefflera with the other major clades of Schefflera sensu lato, wood anatomical diversity is consistent with the polyphyly of this genus based on molecular phylogenetic analyses. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173 , 452–475.  相似文献   

15.
CARLQUIST, S., 1984. Wood and stem anatomy of Lardizabalaceae, with comments on the vining habit, ecology and systematics. Qualitative and quantitative data, based mostly upon liquid-preserved specimens, are presented for Akebia, Roquila, Decaisnea, Holbodia, Lardizabala, Sinofranchetia and Stauntonia . Because Decaisnea is a shrub whereas the other genera are vines, anatomical differences attributable to the scandent habit can be considered. These include exceptionally wide vessels, a high proportion of vessels to tracheids (or other imperforate trdcheary elements) as seen in transection, simple perforation plates, multiseriate rays which are wide and tall, and pith which is partly or wholly sclerenchymatous. With respect to ecology, two features are discussed: spirals in narrower vessels may relate to adaptation to freezing in the species of colder areas, and crystalliferous sclereids seem adapted in morphology and position to deterrence of phytophagous insects or herbivores. The wood may provide mechanisms for maintaining conduction even if wider vessels are deactivated temporarily by formation of air embolisms. Wood and stem anatomy of Lardizabalaceae compare closely to those of Berberidaceae and of Clematis (Ranunculaceae), as well as to other families of Berberidales. Decaisnea is more primitive than these in having consistently sralariform perforation plates and in having scalariform pitting on lateral walls of vessels. A tentative listing of anatomical features which may correspond to generic limits is given.  相似文献   

16.
对灯台树茎次生木质部离析材料进行观察研究,发现其导管分子穿孔板有梯状穿孔板和单穿孔板2种类型,并且其单穿孔板的穿孔外展.具不同类型穿孔板的导管分子有4种类型,即两端均为梯状穿孔板的导管分子;一端是梯状穿孔板,另一端是单穿孔板的导管分子;一端有2个单穿孔板,另一端是梯状穿孔板的导管分子;两端均为单穿孔板的导管分子.  相似文献   

17.
灯台树(Cornus controversa)导管分子穿孔板的类型   总被引:8,自引:1,他引:8  
对灯台树茎次生木质部离折材料进行观察研究,发现其导管分子穿孔板有梯状穿孔和单穿孔板2种类型,并且其单穿孔板的穿孔外展。具不同类型穿孔板的导管分子有4种类型,即两端均为梯状穿孔板的导管; 端是梯关穿孔板,另一端是单穿孔板的导管分子;一端有2个单穿孔板,另一端是梯状穿孔板的导管分子;两端均为单穿孔板的导管分子。  相似文献   

18.
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.
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   

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