油松茎初生结构中树脂道发育的研究

油松茎初生结构中的树脂道是裂生的胞间道,分布在皮层和初生木质部内。皮层树脂道原始细胞团起始于茎端下约140微米处原形成层束两侧的基本分生组织中。在原生韧皮部最早的筛胞分化形成时出现裂生腔隙。其裂隙直径的进一步扩大主要依靠鞘细胞插入到上皮细胞之间和上皮细胞本身的切向伸长。成熟的树脂道近园形,四周由9～16个上皮细胞包被,其外为1～2层鞘细胞。茎的初生结构内树脂道位于皮层内侧的薄壁组织中,通常为8个,排列成一圈。叶迹进入叶子时,其两侧的每一个树脂道也二叉分枝,其一与叶迹一起进入叶子。初生木质部树脂道起源于原形成层细胞,在初生维管组织分化后期才开始发育。每个维管束的初生木质部一般只有一个树脂道。季节的变化对皮层树脂道的形成过程有一定的影响。在一年的不同季节中,从春季到秋季所形成的树脂道出现孔径逐渐变大,上皮细胞的数目和鞘细胞的层数逐渐增多,茎内树脂道的数目增加等变化。     

北柴胡分泌道的发育及组织化学研究

利用植物解剖学和组织化学的方法对北柴胡根、茎和叶中分泌道的分布、发生发育过程以及组织化学进行了研究.研究结果表明,分泌道分布在根中柱鞘组织和次生韧皮部、茎韧皮部和髓,以及叶脉韧皮部内和木质部上方.根中柱鞘中的分泌道来源于中柱鞘细胞,次生韧皮部中的分泌道来源于维管形成层切向分裂向外形成的衍生细胞;茎和叶脉韧皮部内的分泌道起源于原形成层束原生韧皮部外侧的2～3层细胞;茎髓中和叶脉木质部上方的分泌道来源于基本分生组织.这些分泌道腔隙的形成都属于裂生型.组织化学结果表明分泌道是挥发油积累的重要场所.     

油松茎次生木质部中树脂道的发育过程和组织化学研究

利用组织化学方法对油松茎次生木质部树脂道发育过程中上皮细胞内树脂滴和淀粉粒的动态变化进行了研究。发现在树脂道原始细胞阶段,每个原始细胞含淀粉粒较少,含树脂滴稀少。在树脂道形成阶段,淀粉粒数目较多,体积增大,树脂滴也呈递增趋势。在树脂道成熟阶段,淀粉粒数目变化不大,而体积明显变小,树脂滴的体积增大,数目减少。     

CO2浓度加倍对辽东栎维管组织结构的影响

 以辽东栎(Quercus liaotungensis)的13年生幼树为材料,分别培养在大气CO2浓度加倍(700μl·L-1)与对照(350μl·L-1)的开顶式熏气室中,研究CO2浓度升高对其茎次生木质部和次生韧皮部结构的影响。结果表明：经CO2浓度加倍处理的两个生长季内,辽东栎的年轮宽度明显增加,为对照的300％～370％,其中晚材宽度的增加更为显著,为对照的750％～830％。另外,晚材中导管的密度和径向直径分别比对照增加50％和20％;木纤维细胞的比例约为对照的170％。但早材的导管分子和木纤维细胞与对照相比均无显著变化。在CO2浓度加倍条件下,辽东栎的次生韧皮部中含晶韧皮薄壁细胞的数目,每条韧皮纤维切向带中韧皮纤维细胞的数目,以及韧皮纤维长度均有显著增加(p≤0.05)。相反地,韧皮纤维细胞的直径和筛管分子长度却无明显变化。值得提出的是,在CO2浓度加倍的条件下,次生韧皮部的宽度、筛管分子的直径、以及每年形成的韧皮部细胞总数分别为对照的82％、87％和80％。综上所述,大气CO2浓度加倍对辽东栎次生木质部的生长发育具明显的正效应,而对次生韧皮部的细胞总数与筛管分子的影响则呈负效应。     

臭椿茎中分泌道的发育及其组织化学研究

利用植物解剖学方法研究臭椿茎和叶柄中分泌道的结构、分布和发育过程.结果表明:臭椿茎和叶柄中的分泌道分布于髓的周缘,次生木质部中无分泌道.分泌道是由一层分泌细胞围绕分泌腔而构成,分泌细胞外有1～2层鞘细胞.分泌道以裂生方式形成,其发育过程可分为3个阶段:原始细胞阶段、形成阶段和成熟阶段.在原始细胞阶段,一群原始细胞具浓厚细胞质,细胞核清晰可见;形成阶段,原始细胞的中央细胞间细胞壁中层降解,细胞壁分离,形成腔隙,随着分泌细胞数量的增加,分泌腔体积扩大;成熟阶段的分泌道具有12～16个分泌细胞,1～2层鞘细胞,分泌腔直径为30～50μm.组织化学研究表明,分泌细胞及分泌道内含物中含大量的萜类、多糖和脂类物质.机械创伤能够诱导次生木质部中产生创伤分泌道.臭椿茎中的分泌道和创伤性分泌道在抵御生物和非生物胁迫中起重要作用.     

远志根的发育解剖学研究

运用石蜡切片法对远志根的发育过程及1~3年生根的结构进行解剖学研究。结果显示:远志根的原分生组织由3群原始细胞组成,具有典型分生组织的细胞学特征。初生分生组织分化为根冠原、表皮原、皮层原和中柱原;初生结构由表皮、皮层和中柱组成,初生木质部为二原型。次生生长是依靠维管形成层和木栓形成层的活动完成,次生结构从外到内由周皮和次生维管组织组成;远志根次生结构特点为:次生韧皮部在次生维管组织中占主要部分,次生韧皮部中以韧皮薄壁细胞为主且其中储存有丰富的内含物,随着根龄的增加,韧皮薄壁细胞中的内含物也随之增加。3年生的主根中次生韧皮部薄壁细胞中的内含物最丰富;不同年份远志的主根随根龄的增加,周皮、次生韧皮部和次生木质部的面积都呈增加趋势,其中韧皮部和木质部的面积比值随根龄增长呈由小到大的变化,这是远志根的显著特点;根中的周皮发达,具有较厚的木栓层,次生木质部中导管和纤维发达,导管分布频率较高,并具有较大的口径。周皮和次生木质部的结构特征与远志的抗旱特性相适应。     

木质部管状分子的结构及发生

高等植物输导组织由木质部和韧皮部组成,它们都是由几种不同类型的细胞群构成的复合组织。植物体中有机液流的运输主要是韧皮部中的筛分子（筛管和筛胞）,而无机液流的运输则是木质部中的管状分子（导管和管胞）。1管状分子的形态结构管胞是一种原始的输导组织,存在于所有维管植物中,在裸子植物中兼有机械组织的功能。大多数蕨类植物和裸子植物木质部中的输水分子只由管胞组成,管胞是纺锤形的单细胞,成熟时原生质消失,次生壁形成各种纹饰的木质化增厚（见图1）。其长度约为1～2mm,直径约为15～80um。每个管胞以两端斜面连接在一起,…     

五爪金龙茎的解剖结构

运用常规石蜡切片、显微观察及显微照相的方法,对五爪金龙(Ipomoea cairica)茎的结构进行了观察研究,结果表明:五爪金龙茎的解剖结构以初生结构为主,维管形成层已经形成,但次生结构尚不发达。通常具3~6个空腔,初步推断其为裂生式分泌道;表皮外弦向壁增厚,具角质层,具气孔及气室;紧贴表皮内方的1~3层和皮层最内1~3层的细胞可能为分泌细胞;具双韧维管束,木质部极为发达,导管细胞紧密排列,围绕内韧皮部和中央的髓而成一圆周;形成层位于外韧皮部与木质部之间;茎中央是大型薄壁细胞构成的髓,具簇晶。     

五爪金龙茎的解剖结构

运用常规石蜡切片、显微观察及显微照相的方法, 对五爪金龙( Ipomoea cairica) 茎的结构进行了观察研究, 结果表明: 五爪金龙茎的解剖结构以初生结构为主, 维管形成层已经形成, 但次生结构尚不发达。通常具3～6 个空腔, 初步推断其为裂生式分泌道; 表皮外弦向壁增厚, 具角质层, 具气孔及气室;紧贴表皮内方的1～3 层和皮层最内1～3 层的细胞可能为分泌细胞; 具双韧维管束, 木质部极为发达, 导管细胞紧密排列, 围绕内韧皮部和中央的髓而成一圆周; 形成层位于外韧皮部与木质部之间; 茎中央是大型薄壁细胞构成的髓, 具簇晶。     

牛膝根的结构发育与三萜皂苷积累的关系

应用植物解剖学、组织化学定位及植物化学技术,研究了不同发育时期牛膝根的结构特征与三帖皂苷积累的关系。结果表明:牛膝根的初生结构和次生结构类似于一般双子叶植物,其根的加粗主要是由于三生结构的发生和分化。第一圈额外形成层产生于次生韧皮部外侧的薄壁组织细胞和射线细胞,以后的每一圈由前一圈向外衍生的薄壁组织细胞产生。额外形成层无纺锤状原始细胞和射线原始细胞之分,在切向纵切面上呈叠生排列。三生维管束以离心方式排成整齐的同心环状,由薄壁结合组织将其彼此分开,其圈数与额外形成层的圈数是一致的,随着根的个体发育而不断增加。在根的初生结构中,三萜皂苷主要分布于中柱鞘、初生韧皮部及初生韧皮部和初生木质部之间的薄壁组织细胞内;在根的次生结构中,主要分布于次生韧皮部及栓内层的薄壁组织细胞内。当三生结构形成后,除次生韧皮部及栓内层细胞外,在额外形成层和三生维管束韧皮部细胞内均有皂苷类物质积累。三生结构在牛膝根中占主要地位,是三萜皂苷积累与分布的主要场所。在牛膝根的生长发育过程中,三萜皂苷元齐墩果酸的百分含量呈“S”型曲线增长,其根的增长、加粗、三生维管束圈数、三萜皂苷总量及根中干重的积累量都在出苗后约120天达到高峰,此时应为牛膝根的最佳采收期。     

油松树脂道的发生和发育研究

关于松科植物的树脂道,以往都认为是以裂生方式发生。本文通过对油松各类器官的发育解剖学研究,发现其各类器官中树脂道的结构,发生和发育方式并不完全一致,并对产生这些差异的原因进行了分析和讨论。     

Resin ducts of Pinus hatepensis Mill.–Their structure, development and pattern of arrangement

The primary resin ducts in the axis of plants of Pinus halepensis Mill, consist of two separate systems the pattern of which is correlated with the vascular systems of the organs in which they appear. These systems are: (1) ducts of the roots and the hypocotyl; (2) ducts of all the branches and juvenile leaves or scaleS. Both systems are produced by the apical meristemS. In the needles there is a third system of primary resin ducts situated in the mesophyll. These ducts are produced only to a small extent by the apical meristem of the needle and mainly by its intercalary meristem. In addition to these primary ducts of the needle, which form a separate system for each needle, at the base of the needle there may be ducts of secondary origin which are situated within the vein. These are continuous with secondary ducts of the brachyblast axis.
The secondary ducts constitute one system in the secondary xylem and phloem of the roots, branches and needle bases. They are formed by the cambium. In the xylem there are vertical and radial ducts which together form co-planar radial networkS. Each radial duct starts from a vertical duct. The first location of the stimulus for the formation of the two types of ducts is discussed. In the phloem there are only radial ducts, continuous with the radial ducts of the xylem. The cavities of the radial phloem and xylem ducts are not continuous, as there are no intercellular spaces in the region of the cambium.
The innermost vertical ducts of the secondary xylem form a kind of transitional type, in respect of their response to internal and external factors, between the primary resin ducts and the bulk of the secondary resin ducts.     

XYLEM STRUCTURE IN BOTRYCHIUM DISSECTUM SPRENGEL AND ITS RELEVANCE TO THE TAXONOMIC POSITION OF THE OPHIOGLOSSACEAE

The radially seriate xylem of Botrychium dissectum Sprengel resembles secondary xylem, particularly that of gymnosperms, in many important details. It is derived from a layer of cells which strongly resembles a vascular cambium. Presumptive cambial initials are fusiform, and derivatives are radially seriate. The walls of the initials and derivatives have a beaded appearance when viewed in tangential section. The number of xylem elements increases in seasonal increments. Circular-bordered pit pairs occur where tracheids abut other tracheids, and specialized cross-field pit pairs occur where they abut the radially-aligned parenchyma or rays. Cambial activity in Botrychium differs from that found in seed plants and progymnosperms in not producing secondary phloem. Tracheids are less similar to those known in progymnosperms than previously assumed, and some supposed similarities may be less significant than previously assumed. The significance of these dissimilarities is unclear. The recognition that the bulk of the xylem is secondary and that protoxylem strands are arranged as sympodia suggests that Botrychium may be eustelic rather than siphonostelic.     

PHLOEM OF SPHENOPHYLLUM

The phloem of most fossil plants, including that of Sphenophyllum, is very poorly known. Sphenophyllum was a relatively small type of fossil arthrophyte with jointed stems bearing whorls of leaves ranging in form from wedge or fan-shaped to bifid, to linear. The aerial stem systems of the plant exhibited determinate growth involving progressive reduction in the dimensions of the stem primary bodies, fewer leaves per whorl, and smaller and simpler leaves distally. The primary phloem occurs in three areas alternating in position with the arms of the triarch centrally placed primary xylem. Cells of the primary phloem, presumably sieve elements, are axially elongate with horizontal to slightly tapered end walls. In larger stems with abundant secondary xylem and secondary cortex or periderm, a zone of secondary phloem occurs whose structure varies in the three areas opposite the arms of the primary xylem, as opposed to the three areas lying opposite the concave sides of the primary xylem. The axial system of the secondary phloem consists of vertical series of sieve elements with horizontal end walls. In the areas opposite the protoxylem the parenchyma is present as a prominent ray system showing dilation peripherally. Sieve elements in the areas opposite the protoxylem arms have relatively small diameters. In the areas between the protoxylem poles the secondary phloem sieve elements have large diameters and are less obviously in radial files, while the parenchyma resembles that of the secondary xylem in these areas in that it consists of strands of cells extending both radially and tangentially. An actively meristematic vascular cambium has not been found, indicating that this layer changed histologically after the cessation of growth in the determinate aerial stem systems and was replaced by a post-meristematic parenchyma sheath made up of axially elongate parenchyma lacking cells indicative of being either fusiform or ray initials. A phellogen arose early in development in a tissue believed to represent pericycle and produced tissue comparable to phellem externally. Normally, derivatives of the phellogen underwent one division prior to the maturation of the cells. Concentric bands of cells with dark contents apparently represent secretory tissue in the periderm and cell arrangements indicate that a single persistent phellogen was present. Sphenophyllum is compared with other arthrophytes as to phloem structure and is at present the best documented example of a plant with a functionally bifacial vascular cambium in any exclusively non-seed group of vascular plants.     

青麸杨分泌道的解剖学研究

报道了育麸杨分泌道的结构、分布和发育。青麸杨的分泌道是由14—41个分泌细胞围绕细胞间隙而成的腔道,分泌细胞外侧又被多层扁平的鞘细胞所包围。青麸杨的分泌道主要分布于根、茎、叶、花和果实的维管束的韧皮部内,此外,茎的髓中也有少量分泌道,分泌道位于木质部脊处的薄壁组织内,排列成一圈。青麸杨各器官中的分泌道的发生方式一致,都是裂生方式起源的。     

RELATION OF DWARFMISTLETOE (ARCEUTHOBIUM) TO THE XYLEM TISSUE OF CONIFERS. II. EFFECT OF THE PARASITE ON THE XYLEM ANATOMY OF THE HOST12

Srivastava , L. M., and K. Esau , (U. California, Davis.) Relation of dwarfmistletoe (Arceuthobium) to the xylem tissue of conifers. II. Effect of the parasite on the xylem anatomy of the host. Amer. Jour. Bot. (48(3): 209–215. Illus. 1961.—The changes in the xylem anatomy induced by dwarfmistletoe infection were studied in 7 coniferous species. The most pronounced abnormalities are observed in the shape and size of the infected rays. Because of the presence of parasite tissue, the rays assume a hypertrophied appearance; moreover, they fuse to form large composite rays. The union of rays involves intrusive growth of ray cells and displacement of fusiform initials. Some division of fusiform initials also occurs. Rays may increase in number and they may contain more host cells than normal rays. Axial tracheids in infected host woods differ more or less strongly from those of noninfected woods. They may be shorter, wider, and more irregular in shape than the axial tracheids in healthy wood. The samples of xylem from infected pines had a larger number of resin canals than those from healthy trees. Resin canals were also found in infected Tsuga, which normally lacks these structures.     

药用植物商陆(Phytolacca acinosa Roxb.)根中异常次生结构的发育解剖学研究

本文报道了药用植物商陆根中异常次生结构的发生和发育过程。商陆根的初生结构和早期的次生结构都是正常的。但是,后来在维管柱的外围以离心的顺序先后产生5-7轮异常形成层.第一轮异常形成层起源于次生韧皮薄壁细胞和射线细胞。后一轮异常形成层在前一轮异常形成层向外产生的薄壁结合组织中发生。各轮异常形成层都以正常的活动方式产生同心环状排列的异常维管束以及它们之间丰富的薄壁结合组织,从而使根变成肉质状。薄壁结合组织细胞以及异常维管束内的薄壁组织细胞中贮藏有淀粉粒。     

Anatomy of Gymnosperms Endemic to China,II. Taiwania flousiana Gaussen (Taxodiaceae)

Taiwania Hayata contains two species: T.flousiana Gaussen and T. cryptomerioides Hayata, both endemic to China. T. flousiana was investigated with both light and scanning electron microscopes in respect to shoot apex, external and internal surfaces of leaf cuticle, primary leaf, juvenal and mature leaves, young stem, secondary phloem and wood of stem, etc, It is shown that the shoot apex consists of the following five regions: (1) the apical initials; (2) the protoderm, (3) the subapical moher cells;. (4) the peripheral meristem, and (5) the pith mother cells. The periclinal and anticlinal division of the apical initials takes place with approximately equal frequency. The juvenal leaf is nearly triangular or crescent-shaped in cross section and belongs to the leaf type II. The mature leaf is quadrangular in cross section (the leaf type I). There are a progressive series of changes in size and shape of the leaf cross section. The stoma of the mature leaf is amphicyclic and occasionally tricyclic. The crystals in the juvenal leaf cuticle are more abundant than those in the mature leaf cuticle. The transfusion tissue conforms to the Cupressus type. The structure of juvenal leaf is the nearest to that in Cunninghamia unicanaliculata D. Y. Wang et H. L. Liu, while the mature leaf is similar to that of the Cryptomeria. Sclerenchymatous cells of the hypodermis in the young stem comprise simple layers and are arranged discontinuously. No primary fibers are found in the primary phloem. Medullary sheath is present between the primary xylem and the pith. There are some sclereids in the pith. The secondary phloem of the stem consists of regularly alternate tangential layers of cells in such a sequence: sieve cells, phloem parenchyma cells, sieve cells, phloem fibers, sieve cells. The phloem fiber may be divided into thick-walled and thin-walled phloem fiber. The crystals of calcium oxalate in the radial walls of sieve cells are abundant. Homogeneous phloem rays are uniseriate or partly biseriate, 1-48 (2-13) cells high, and of 26-31 strips per square mm. Growth rings of the wood in Taiwania are distinct. The bordered pits on the radial walls of early wood tracheids are usually uniseriate, occasionally paired and opposite pitting. Wood parenchyma is present, and its cells contain brown resin substances. Their end walls are smooth, lacking nodular thickenings. Wood rays are homogeneous. Cross-field pits are cupressoid. Resin canals are absent. Based on the anatomy of Taiwania and comparison with the other genera of Taxodiaceae, the authors consider the establishment of Taiwaniaceae not reasonable, but rather support the view that the genus is better placed between Cuninghamia and Arthrotaxis in Taxodiaceae.     

ON THE FINE STRUCTURE OF THE CAMBIUM OF FRAXINUS AMERICANA L

The fine structure of ash cambium was studied after glutaraldehyde-osmium tetroxide fixation. The fusiform and ray initials are essentially alike, and both have the basic complement of organelles and membranes typical of parenchyma cells. The varied behavior of the two types of initials and the role of cambium in oriented production of the xylem and phloem are still unexplained phenomena. Actively growing cambial cells are highly vacuolate. They are rich in endoplasmic reticulum of the rough cisternal form, ribosomes, dictyosomes, and coated vesicles. Microtubules are present in the peripheral cytoplasm. The plasmalemma appears to be continuous with the endoplasmic reticulum and produces coated vesicles as well as micropinocytotic vesicles with smooth surfaces. The plastids have varying amounts of an intralamellar inclusion which may be a lipoprotein. The quiescent cambium is deficient in rough ER and coated vesicles and has certain structures which may be condensed proteins.