ANATOMICAL STUDIES OF CATHAYA (PINACEAE)

Cathaya Chun et Kuang is a monotypic genus and one of the gymnosperms endemic to China. We investigated Cathaya argyrophylla with both light and scanning electron microscopy to study the external and internal surfaces of leaf cuticle, leaf blade, petiole, shoot apex, young stem, bark, wood, young and old roots, and mycorrhizae. It is shown that Cathaya has unique characteristics as well as common features of the Pinaceae, there being a difference between Cathaya and Pinus and the rest of the family. So far as the vegetative organs are concerned, the genus is most closely related to Pseudotsuga and Larix. Data derived from the study of structures of vegetative organs of Cathaya are very different from those of reproductive organs, indicating the complexity of the problem of systematics and evolution in these plants. However, the present study supports the view that Cathaya should not be included in the genus Pseudotsuga as a new species.     

SPORE MORPHOLOGY IN THE CYATHEACEAE. III. THE GENUS TRICHIPTERIS

Scanning electron microscopy supported by light microscopic L-O analysis is used in a palynological study of the genus Trichipteris of the tree fern family Cyatheaceae. The spores of all but two of the 55 species are investigated and the results are related to previous findings for Trichipteris species in the literature. A perine layer consisting of a network of slender, smooth- or rough-textured interlocking strands with free ends uniformly characterizes the genus and is the same as the perine type previously reported in neotropical species of Sphaeropteris excluding the S. horrida group. The exine is analyzed both in spores which have not yet developed the perine layer and in spores whose perine has been removed by chemical treatment. Exine sculpturing shows great variation in the genus, ranging from essentially psilate to variously pitted (foveolate, foraminate), with topography ranging from plane to verrucate-tuberculate, and with the verrucae-tubercles themselves often variously pitted. In many instances, exine sculpturing types correlate with the infrageneric species groupings or affinities hypothesized by the recent monographers. In other cases, palynological characters offer new insight into species relationships that were previously unclear to monographers or that were interpreted differently on the basis of other characters. The exine sculpturing types reinforce the relationship evident between Trichipteris and neotropical Sphaeropteris on the basis of perine morphology.     

ANATOMICAL AND PHYSIOLOGICAL STUDIES OF FLORAL TUBE ELONGATION OF CROCUS VERNUS (IRIDACEAE)

Intact floral tubes of Crocus vernus grown under controlled conditions elongated 50 mm in 8 days. Mitoses of the epidermal cells did not occur during the growth of the intact tube; however, cells did elongate from 50 μm to 150 μm, a three-fold increase in cell length. When the floral buds were excised and maintained in distilled water, elongation of floral tubes was inhibited by 46%. The presence of the ovary or the addition of nutrients had no significant effect upon the elongation of the floral tubes of excised buds. When the excised floral buds were placed in 10^–6 m indoleacetic acid, the final tube lengths exceeded that of the water controls by 30% and achieved 91% of the elongation of the intact tubes. Gibberellic acid and kinetin had no effect on floral tube elongation. As with the intact floral tubes, mitoses of the epidermal cells did not occur during the elongation of the excised floral tubes.     

窝梨果实结构及发育的研究

窝梨果实是由托杯和子房共同发育形成的假果,其横切面上,由外向内可看到表皮层,果肉,果心等几部分。表皮层,果肉由托杯发育而来,其中发布着维管束及石细胞等,果心是由子房发育而成,子房下位,５心皮组成５室,每室具２个倒生胚珠。     

黄杨花蜜腺的形态解剖学研究

黄杨花单性,雌雄同株,雄花花蜜腺４枚,乳头状,着生于退化雌蕊子房顶部;雌花花蜜腺３枚,短柱状,位于３枚花柱之间。雌、雄花蜜腺均由分泌表皮、产蜜组织和维管束构成,在发育过程中产蜜组织细胞的液泡都发生有规律的变化。雌花蜜腺大,属非淀粉型蜜腺,泌蜜量大,蜜汁含糖分多,维管束中仅含韧皮部;雄花蜜腺小,属淀粉型蜜腺,泌蜜量小．蜜汁含糖量小,维管束由木质部和韧皮部构成。     

星叶草下胚轴解剖

星叶草的茎部很短,下胚轴的长度几乎占有植株的整个高度。纤细的下胚轴主要依靠表皮层细胞外壁角质膜的增厚,以及中央初生木质部束的支持。初生木质部与初生韧皮部之间可见到2—3层排列规则或不规则的薄壁组织细胞,但是没有维管形成层的发生。这种植物的根茎维管组织的过渡区域,看不到一般双子叶植物中所见到的初生木质部束扭曲、分开或倒转的现象。伸向子叶的子叶迹,直接由原生木质部极外面的一群薄壁组织细胞分化形成。第一和第二片叶子的叶迹则在初生韧皮部中间发生。     

荠的花蜜腺发育解剖学研究

荠(Capsella brsa-pastoris(L.)Medic.)的花蜜腺共4枚,都呈半圆形、绿色。蜜腺由分泌表皮、泌蜜组织和维管束组成,属于结构蜜腺。在花的各部分分化后,由花托表层细胞恢复分裂能力形成蜜腺原基。在蜜腺发育过程中,泌蜜组织的液泡和淀粉粒发生有规律的变化。荠的花蜜腺按其着生位置,属于花托蜜腺;其发生方式属居间生长,4枚蜜腺同步发生;根据其结构和泌蜜前后的多糖物质变化分析,其原蜜汁源于维管束的韧皮部,通过泌蜜组织输送到气孔下腔,然后由变态气孔排出。     

蒲公英花蜜腺的发育解剖学研究

蒲公英的花蜜腺位于花柱基部,呈筒状围绕花柱,新鲜时呈绿色,属于花柱蜜腺。其结构由分泌表皮和泌蜜组织组成,不含有维管束。分泌表皮上有气孔分布,孔下室发达,泌蜜组织的内侧与花柱维管束相邻。蜜腺由花柱基部的细胞发育而来,在蜜腺发育的过程中,其细胞结构和贮藏都发生了规律性的变化。原蜜汁由花柱基部的维管束提供,经过泌蜜组织细胞加工成蜜汁后,通过气孔排出体外。     

西洋参根的发育解剖学研究

西洋主根顶端的原分生组织由三群原始细胞组成。初生木质部为三原型。维管形成层产生的次生维管组织中薄壁细胞占主导地位;维管分子量少、聚集成群,分散在薄壁组织中。周皮加、周皮发生较迟,其木栓形成层由紧靠内皮层的皮层细胞产生。不同年龄西洋参主根随着龄龄的增加,周皮、次生真心皮部和木质部面积均呈增加趋势,但韧皮部与木质部面积比值自５：１下降至１：１。一年生根由中柱鞘产生初生分泌道,由维管形成层产生一圈次生分     

十齿花次生木质部和次生韧皮部的解剖学研究

对十齿花的次生木质部和次生韧皮部结构进行了观察,并与卫矛科其它８属植物的木质部作子下齿花次生木质部和次生韧皮部的主要特点是;木质部导管分子相对较长,其末端倾斜,具梯状穿孔板,由１４个横隔组成。纤维和纤维管胞均有横隔。韧皮部筛管分子相对较短,其端壁水平或略倾斜,具单筛板,缺少纤维。     

独叶草的根和节部及叶的解剖学研究

报道了独叶草根、节部和叶的剖解学特征。这些器官在解剖学上表现出的突出点是：根具２个以上的根毛区（与星叶草机相同）,中有少量的次生生长,皮层细胞中具内生真菌;变态叶的叶迹或为单迹单维管组织束,或为单迹２维管组织束,或２迹在向皮层外部延伸过程中合并为具２条维管组织束的单迹;叶柄维管束不存在厚壁的维管束鞘,且在由基部向顶部延伸的过程中常发生复杂的分枝及汇合;叶片具有同形的叶肉植物,叶脉维管束鞘具２层细胞     

COMPARATIVE STUDIES OF THE NODAL AND VASCULAR ANATOMY IN THE NEOTROPICAL CYATHEACEAE. I. METAXYA AND LOPHOSORIA

Comparative studies of the nodal and vascular anatomy in the monotypic genera Metaxya and Lophosoria are discussed as they relate to the taxonomy and phylogeny of the Cyatheaceae. Both genera are distinctive and primitive with respect to habit, stem and petiole indument, stelar pattern, and nodal anatomy. Metaxya possesses a prostrate, dorsiventral rhizome, whereas a short, upright radial stem occurs in Lophosoria. Trichomes occur on the stems and leaf petioles of these genera. Both Metaxya and Lophosoria have a spiral phyllotaxy, and adventitious buds occur on the petiole bases. The stelar pattern is basically a siphonostele, although frequently a dictyostele is found in Lophosoria. Accessory bundles are lacking in both genera. A characteristic petiole pattern is found in these genera, with an increase in complexity from an undivided strand in Metaxya to the three-parted petiole pattern in Lophosoria. Data from nodal and vascular anatomy indicate that these taxa are distinct from the other genera in the Cyatheaceae and belong in an independent position at the base of the Cyatheoid line, although in some respects an affinity to members of the Dicksoniaceae is indicated.     

黄连种子后熟过程的解剖学研究

黄连种子采收埋土后,需要经过9—10个月才能出土萌发。这是由于黄连种子在4—5月脱落吋,胚未成长,一般尚只在球形胚或心形胚早期。后来经过较长时期心形胚阶段,才变成鱼雷形胚。大约要到翌年1月时,胚胎完全成长。所以黄连种子不易萌发是因为胚胎尚未成长。不过,黄连幼胚的胚轴上端的顶端分生组织旁第一片真叶原基则出现很早。从黄连胚胎的整个成长过程来看,如果创造某种条件设法缩短心形胚阶段,可能缩短整个种子的萌发过程。     

裂叶沙参与泡沙参解剖生态学的比较研究

借助于光镜和扫描电镜,系统观察了濒危植物裂叶沙参(Adenophora lobo-phylla Hong.)的根、芦头、茎和叶的解剖特征及茎、叶、种子的表面形态特征,并将有关性状与广布种泡沙参(A.potaninii Korsh.)作了对比研究。结果表明,两种沙参在叶表皮细胞形状,垂周壁式样,角质层初级雕纹及次级雕纹;叶片气孔形状及外拱盖外缘纹饰及内缘形状,保卫细胞上角质层薄厚及蜡质纹饰;叶表毛状体形状及纹饰,茎中皮层占茎横切面的比例;茎中有无髓纤维等方面存在着明显差异。相对于泡沙参,裂叶沙参单株叶面积大,生物量高,表皮角质层薄,单位面积内被毛数量少,栅栏组织薄,气孔周围蜡质沉积颗粒少;茎的直径大,皮层较薄等。这些特征表明裂叶沙参对旱生生境适应能力弱,而泡沙参对旱生生境适应能力强。     

石山苏铁与锈毛苏铁羽片解剖学研究

研究了石山苏铁与锈毛苏铁叶的羽片横切面结构,结果表明,石山苏铁叶表面具厚的角质层,表皮细胞壁厚,排成整齐的一列：下皮层厚壁细胞仅分布于中脉隆起区和叶缘：叶肉由栅栏组织和海绵组织构成,栅栏组织为排列整齐的柱状细胞组成,位于近轴面的表皮层下方,并延伸至中脉区：海绵组织的细胞分布于副转输组织两侧,含晶细胞少;韧皮部在远轴面,排成弧形;木质部在近轴面,管胞分散,锈毛苏铁的羽片横切面结构在叶缘的形态,叶脉区隆起形态,韧皮部形态,分泌道有无及下皮层厚壁细胞的特点等方面与石山苏铁存在较明显的差异,本文支持把两者作为独立种的观点。     

葛莱德拉幼苗初生维管系统的解剖学研究

葛莱德拉（Ｇａｒｉｄｉｌｌａｍｎｇｅｌｌａｓｔｒｕｍ）幼苗的子叶节区中部保留有管状中柱阶段和具单隙双迹的子叶节,这在被子植物幼苗中是十分罕见的,并且对研究被子植物的起源也提供了一份基础资料。     

中国木兰属和含笑属导管分子的比较解剖

本文对我国木兰科的39种木兰属和含笑属植物次生木质部的导管分子进行了初步分析。两属导管分子的长度和宽度略有差异。木兰属中多数种的导管分于有单穿孔板,但有的可见到梯状穿孔板。含笑属植物的导管分子大多具有梯状穿孔板,仅有一种可看到单穿孔板。在具有梯状穿孔板的木兰属植物中,穿孔板的横隔数目较含笑属的多。木兰属的导管壁上一般无螺纹加厚;含笑属则相反。此外,在两属之间,导管尚存在一些其它差异。     

大花蕙兰营养器官及原球茎的解剖学研究

对大花蕙兰试管苗营养器官及原球茎的解剖学研究结果表明：根由复表皮、皮层和维管柱组成,根毛丰富,皮层发达,内皮层明显,初生木质部月多元型,中央具髓,根茎由表皮,基本组织和维管束构成,维管束散生,属周木型;叶为等面叶,在上下表皮处分布有成束的厚壁组织,叶肉无栅栏组织和海绵组织之分,细胞排列紧密,维管束鞘由机械组织构成。原球茎原生分生组织的原套仅一层细胞,在顶端分生组织后面的薄壁细胞中,存在胚性细胞,由胚性细胞经球状胚可发育成幼原球茎。     

江豚眼的解剖学和组织学研究

统计结果表明:与黄海沿岸种群江豚相比,长江种群江豚眼中央至吻端的平均距离显著较小,与长江弱光环境相适应。长江种群平均眼裂高比较小,眼球平均相对水半径比较短,而前后径比较长。眼球较趋近于圆球型。视觉较近视。在显徽与亚显微结构方面未发现两种群之间有差异。江豚无典型的视锥,而具有细胞核和内节呈视锥状、外节呈视杆状的一种中间型视细胞。