席草品种茎解剖结构与经济性状的相关性

席草（ＪｕｎｃｕｓｅｆｆｕｓｕｓＬ．ｖａｒ．ｄｅｃｉｐｉｅｎｓＢｕｃｈｅｎ）表面纵向条纹的深浅和数量是影响席草茎秆光洁度的主要因素。基本组织周边沿切向分布的纤维束、呈三层排列的大小维管束及分布在其中的纤维细胞的特殊排列使席草茎秆具有较好的坚韧性。髓部细胞的特化、富含气体的海绵状组织的形成及基本组织内出现的腔隙道使席草茎秆具有较好的弹性和耐压力。     

生长调节剂DPC和营养物质KH2PO4协同作用对棉蕾茎解剖结构的调…

在自然光照和遮荫的弱光条件下研究了ＤＰＣ（助壮素）、ＫＨ２ＰＯ４（磷酸二氢钾）单独和混合浸种对棉苗茎组织解剖结构的影响,结果表明在两种光照条件下,ＤＰＣ、ＫＨ２ＰＯ４对棉苗茎的组织结构都有不同程度的影响。其中以ＤＰＣ＋ＫＨ２ＰＯ４处理效果优于单独使用,特别是弱光条件下,此效应更明显。ＤＰＣ＋ＫＨ２ＰＯ４处理使棉苗茎秆粗壮,茎秆密度（单位茎高度内干物质重）增加。茎中维管组织发育好,维管束数目多,每一     

云南野生稻叶茎根组织结构特性的比较研究

采用徒手切片法对云南3种野生稻和栽培稻的叶片、茎秆及根的组织结构进行比较研究,以明确野生稻的内部结构,为进一步揭示其结构与云南野生稻的生长势旺盛、营养吸收能力强、抗某些病虫害能力强的关系奠定基础。结果表明,(1)云南野生稻与栽培稻叶片主脉、茎秆及根的组织结构差异显著,其中景洪疣粒野生稻、景洪药用野生稻与栽培稻的差异最明显。(2)在叶主脉结构中,景洪疣粒野生稻无气腔结构,维管束数量少、面积小;景洪药用野生稻、3个普通野生稻材料存在多个维管束和气腔结构,维管束、束内导管直径及气腔面积较栽培稻大,而栽培稻中的气腔均为2个。(3)在茎秆结构方面,景洪疣粒野生稻茎秆最小,维管束数量最少,其茎壁内的维管束排列方式与栽培稻不同;景洪药用野生稻和普通野生稻茎秆及茎壁较栽培稻粗厚,维管束数量也较栽培稻多,普通野生稻的茎壁中有通气组织。(4)在根的组织结构中,3种野生稻的导管数量较多,导管直径及中柱面积较栽培稻大,外皮层出现了具有凯氏带功能的凯氏点等。     

陕西4个漆树品种外部形态及次生韧皮部结构的比较

采用形态观测和石蜡切片对陕西4个漆树品种的外部形态和树皮次生韧皮部的组织结构进行了比较分析.结果表明:4个漆树品种间在树冠、树高、皮孔形状和排列方式、复叶的小叶数及总叶柄、叶轴和叶脉上的被毛等外部形态性状上差异明显;品种间树皮基本结构相同,次生韧皮部结构和组成相似,其差异主要表现在筛管直径大小、乳汁道直径大小及单位面积内数量、石细胞群大小及单位面积内数量、有/无功能韧皮部厚度之比等方面.     

庞泉沟自然保护区华北落叶松土壤种子库的研究

采用样地内小样方取样,物理方法分离,室内测量,试验,分析的方法,对庞泉沟国家级自然保护区内,华北落叶松４个林型的林下土壤种子数量,质量及分布进行了研究。分析了影响林下土壤种子数量的因素,提供了华北落叶松土壤种子库的基本背景。     

水稻茎秆形态结构特征和化学成分与抗倒伏关系综述

水稻茎秆形态结构特征和化学成分与其抗倒伏性能相关。本文对水稻茎秆高度、茎秆基部第1、2节间长度、茎秆粗细、茎壁厚度、厚壁组织(机械组织)数量和强度、维管束数量、细胞壁纤维素和木质素含量、细胞中碳水化合物积累的数量、硅与钾的含量以及茎秆抗倒伏相关的QTL等与水稻的抗倒伏性的相互关系进行了综述,为水稻抗倒伏优良品种性状的选育提供参考。     

粗秆高产小麦茎结构特性分析

以高产小麦（Ｔｒｉｔｉｃｕｍ ａｅｓｔｉｖｕｍ Ｌ．）新品种“兰考９０６－４”与北京大面积种植的小麦品种“京４１１”为实验材料,运用植物解剖学、化学和力学的理论与方法,对粗秆的高产小麦茎结构特性做了详细的比较研究。结果表明：粗秆的高产小麦品种茎秆在物理力学特性、维管束结构特征以及木质素含量等方面,均明显优于一般小麦品种。因此,在超高产小麦品种的育种中,重视外源基因的引进,改进茎秆的结构特性及提高木     

玉米茎秆细胞壁和组织构建对抗压强度的影响

耐密抗倒伏玉米品种是玉米育种的重要方向,探究影响玉米茎秆抗压强度的机制是培育玉米新品种的重要途径。本实验采用组织化学、显微观察的方法研究了10个玉米品种茎秆的形态结构、解剖特征和细胞壁的化学组成,并分析了这些变量之间的相关性,结果表明:茎的皮层/半径、厚壁组织比例、机械组织比例和纤维素含量、木质素含量与抗压强度呈极显著正相关关系;薄壁组织比例、茎长/茎粗、维管束个数与抗压强度呈极显著负相关关系。利用共线性诊断和逐步线性回归分析发现,影响茎秆抗压强度的主要因素为皮层/半径、机械组织比例、维管束个数、纤维素含量和木质素含量。利用通径分析进一步定量研究了这5个变量与抗压强度之间的直接作用和间接作用,明确了决定玉米茎秆抗压强度的主要因素为纤维素含量、木质素含量和单位面积维管束个数。本实验还建立了玉米茎微观结构与细胞壁化学构成的数学模型,为进一步揭示玉米茎微观力学形成机理提供了思路,进而为耐密抗倒伏玉米育种提供了研究方向。     

纬度对甜高粱营养生长和籽粒产量的影响

为了解甜高粱〔Sorghumbicolor(L.)Moench〕各品种在我国的适应性,在不同地区进行了‘意达利’、‘雷伊’、‘凯勒’、‘M81E’的品种比较试验,对各品种的生育期、株高、茎秆直径、茎秆重量、茎秆汁锤度、籽粒产量与纬度的关系进行了一元线性回归分析。结果表明:纬度变化,实际上是日照长度的变化,对甜高粱营养生长有影响,高纬度有利于其营养生长。各品种对纬度变化反应敏感程度从大到小为:‘意达利’>‘M81E’>‘凯勒’>‘雷伊’。纬度变化对甜高粱籽粒产量也有影响,4个品种的敏感程度从大到小为:‘意大利’>‘M81E’>‘凯勒’>‘雷伊’,4个品种的生育期、茎秆含糖量(汁锤度)、籽粒产量也随着纬度的增高而增加     

我国曼陀罗属的花粉形态及其在分类上的意义

本文收集了国内曼陀罗属(Datura L.) 11个不同的生态型,在光学显微镜和扫描电镜下,进行了花粉粒形态的比较观察。该属花粉粒均为球形或稍扁,具3孔沟型。花粉粒外壁表面的纹饰可作为分属、分组、分种的依据之一。可分为三个类型,与植物形态分类基本一 致,即：具皱波-细网状纹饰(曼陀罗组); 具网状条纹或条纹,条脊表面有细颗粒或粗糙(洋金花组); 具条纹,条脊表面有蚕体状环纹及细颗粒(木本曼陀罗组)。种以下的变种或栽培变种,花粉粒的形态特征不足以作为分类的依据。     

DEVELOPMENTAL ANATOMY OF THE STEM OF WELFIA GEORGII,IRIARTEA GIGANTEA,AND OTHER ARBORESCENT PALMS: IMPLICATIONS FOR MECHANICAL SUPPORT

Changes in stem anatomy with radial position and height were studied for the arborescent palms Welfia georgii, Iriartea gigantea, Socratea durissima, Euterpe macrospadix, Prestoea decurrens, and Cryosophila albida. Vascular bundles are concentrated toward the stem periphery and peripheral bundles contain more fibers than central bundles. Expansion and cell wall thickening of fibers within vascular bundles continues throughout the life of a palm, even in the oldest tissue. Within individual vascular bundles, the fibers nearest the phloem expand first and fiber cell walls become heavily thickened. A front of expanding fibers moves outward from the phloem until all fibers within a vascular bundle are fully expanded and have thick cell walls. Peripheral vascular bundles differentiate first and inner bundles later. In the stem beneath the crown, vascular bundles and ground tissue cells show little or no size increase, but marked cell wall thickening during development for Welfia georgii. Beneath the crown, diameters of peripheral vascular bundles increase more than twofold for Iriartea gigantea, while diameters of central bundles do not increase. In Iriartea stems, ground tissue cells at the periphery elongate to accommodate expanding vascular bundles and cell walls become thickened to a lesser degree than in fibers; central ground tissue cells elongate markedly, but cell walls do not become thickened; and large lacunae form between central parenchyma cells. For Iriartea, Socratea, and Euterpe, sustained cell expansion results in limited, but significant increases in stem diameter. For all species, sustained cell wall thickening results in dramatic increases in stem stiffness and strength.     

元宝山南方红豆杉的解剖结构及其环境适应性

以分布于广西北部元宝山自然保护区的南方红豆杉为研究对象,利用石蜡切片方法和光学显微技术,对其茎和叶的解剖结构及其对环境的适应性进行了研究和探讨。结果表明:(1)茎和叶的表皮细胞均较小,外壁角质层发达,胞内富含单宁类物质;(2)1～2年生茎无周皮,皮层基本薄壁组织分成5瓣,茎横切面呈"梅花"形,3年生茎具周皮,次生韧皮部薄壁组织发达、细胞内含物丰富;(3)叶片下表皮气孔带和中脉带均有角质层乳状突起分布,乳突大而密集,气孔仅分布于下表皮,气孔器为双环型,叶肉海绵组织发达,约占叶肉厚度的3/4。进一步分析显示,元宝山南方红豆杉茎和叶的解剖结构与元宝山的中亚热带山地气候和阴生环境相适应;与前人研究结果不同,本研究发现叶片角质层乳状突起遍布下表皮,这可能与元宝山南方红豆杉的分布区海拔高且环境温度低有关。     

海南龙血树的形态组织学研究

采用植物解剖学、显微切片技术等,分别对海南龙血树含有树脂的茎、不含树脂的茎、幼根和叶片等进行了系统的组织学研究。结果表明：老茎主要由栓化层、皮层、形成层和基本组织4部分组成,树脂主要分布在基本组织内维管束的导管和纤维中。叶片为等面叶,气孔主要分布在下表皮上、具有明显的孔下室,上下表皮内侧分布着大量的纤维束。幼根由根被细胞、皮层和维管柱组成。根、茎、叶的部分薄壁细胞中均含有晶束。海南龙血树营养器官的结构特征与干旱、高温和贫瘠的生态环境相适应。这些结果可为海南龙血树的开发和利用提供基本的解剖学证据。     

In vitro morphogenesis patterns from shoot apices of sugar cane are determined by light and type of growth regulator

The regeneration patterns of shoot apices derived from in vitro plants of four varieties of sugar cane in response to different growth regulators and light were evaluated. The cellular origin of the regeneration processes was also investigated. Explants cultivated on medium supplemented with NAA and incubated under light showed direct bud regeneration from cells of external layers of the ground parenchyma of the stem. Explants cultivated in the dark on medium supplemented with low concentrations of picloram (PIC) or 2,4D (4.0 and 4.5 μM, respectively) showed callus formation derived from the ground parenchyma of stem and development of preembryogenic masses derived from bundle sheath cells facing the phloem tissue of immature leaves. Somatic embryos at further developmental stages were visible following transfer to medium devoid of growth regulators and incubation under light. When incubated under light since the begining of the experiment, explants cultivated in the presence of higher PIC or 2,4D concentrations (40 and 22.6 μM, respectively) first displayed direct organogenesis from external layers of the ground parenchyma of the stem, followed by the development of organogenic calluses. Preembryogenic masses were also observed from bundle sheath cells of immature leaves. However, in contrast to the cultures pre-incubated in darkness for 30 days, the subsequent stages of embryo development were not detected. The regeneration efficiency of calluses induced by 2,4D and PIC was generally increased following desiccation in laminar flow or incubation on medium solidified with phytagel.     

ONTOGENY AND COMPARATIVE ANATOMY OF THORNS OF HAWAIIAN LOBELIACEAE

Carlquist , Sherwin . (Claremont Graduate School, Claremont, Calif.) Ontogeny and comparative anatomy of thorns of Hawaiian Lobeliaceae. Amer. Jour. Bot. 49(4): 413–419. Illus. 1962.—Species of Rollandia and Cyanea (sections Genuinae and Palmaeformes), endemic Hawaiian genera of Lobeliaceae, are unique in the family in possessing thorns and thorn-like structures on leaves, and in some cases, on stems and flowers. These thorns always originate in conjunction with a unicellular, non-glandular trichome which terminates the thorn. Ontogenetic studies show that divisions leading to the formation of the thorn occur in the ground meristem as soon as the trichome is differentiated. Periclinal divisions predominate at first, but anticlinal and diagonal ones are also present at all stages. Thick secondary walls are formed on the trichome and other epidermal cells near the thorn tip. Periderm forms on old thorns of stems. Vascular tissue and laticifers are absent in thorns. Thorns in Cyanea and Rollandia seem best interpreted as specializations within these genera.     

STRUCTURALLY PRESERVED FOSSIL PLANTS FROM ANTARCTICA. I. ANTARCTICYCAS,GEN. NOV., A TRIASSIC CYCAD STEM FROM THE BEARDMORE GLACIER AREA

Silicified stems with typical cycadalean anatomy are described from specimens collected from the Fremouw Formation (Triassic) in the Transantarctic Mountains of Antarctica. Axes are slender with a large parenchymatous pith and cortex separated by a narrow ring of vascular tissue. Mucilage canals are present in both pith and cortex. Vascular tissue consists of endarch primary xylem, a narrow band of secondary xylem tracheids, cambial zone, and region of secondary phloem. Vascular bundles contain uni- to triseriate rays with larger rays up to 2 mm wide separating the individual bundles. Pitting on primary xylem elements ranges from helical to scalariform; secondary xylem tracheids exhibit alternate circular bordered pits. Traces, often accompanied by a mucilage canal, extend out through the large rays into the cortex where some assume a girdling configuration. A zone of periderm is present at the periphery of the stem. Large and small roots are attached to the stem and are conspicuous in the surrounding matrix. The anatomy of the Antarctic cycad is compared with that of other fossil and extant cycadalean stems.     

Hydrodynamics and Biomechanics of the Submerged Water Moss Fontinalis antipyretica - a Comparison of Specimens from Habitats with Different Flow Velocities

Flow velocity has an influence on the hydrodynamic and biomechanical properties, as well as on the morphology and the anatomy of the submerged water moss Fontinalis antipyretica Hedw. Cross-sections of the plant stems show two main types of tissues. The strengthening tissue in the outer part is characterized by thick-walled cells with a small lumen, the parenchyma in the centre by thin-walled cells with a large lumen. The specimens from habitats of different flow velocities differ in the proportions of the strengthening tissue and the branching angle of the leaves. A flow tank with a special sensitive two-component balance inserted into the bottom of the flume was used to measure the hydrodynamic drag, which acts on the plant stems at different flow velocities. The drag forces increase with the length of the plant. Mechanical properties such as elasticity and ultimate strength of the plant stems were tested in tension. Relating the data to the relative proportions of the strengthening tissue results in different estimates of Young's moduli for the strengthening tissue of plants from the different sites. The critical strains to which the stems can be extended are remarkably high. Loading and unloading cycles reveal viscoelastic behaviour of the stem tissues. In the first cycle plastic deformation is also observed, but only to a lesser degree in subsequent cycles.     

罗布麻和白麻不同居群植物的比较解剖学研究

新疆罗布麻和白麻８个居群植物的比较解剖学研究表明,它们为适应旱生环境,形态结构都发生变化;叶表皮解质层厚;下表皮多具有下皮层;气孔皆分布于下表皮,且具孔下室;输导组织和机械组织发达;有些叶片上下都具栅栏组织。茎中初生韧皮纤维发达;髓外围存在异常的维管组织－内生韧皮部。因生境有所不同,白麻比罗布麻具有更为显著的旱生结构。     

Wood and stem anatomy of woody Amaranthaceae s.s.: ecology, systematics and the problems of defining rays in dicotyledons

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.     

THE MORPHOLOGY AND RELATIONSHIPS OF RHODEA,TELANGIUM, TELANGIOPSIS,AND HETERANGIUM

This study deals with four form or organ genera from the Upper Mississippian (Chester Series) of the Illinois Basin, and provides evidence that they were produced by a single natural genus with gymnospermous affinity. The plant remains—compressions, impressions, petrifactions, and specimens that combine compression or impression with petrifaction—allow examination of both external morphology and internal anatomy. The specimens include foliage corresponding to Rhodea, stems and petioles corresponding to Heterangium, and synangiate fructifications corresponding to either Telangium or Telangiopsis. The stems and foliage are considered parts of the same plant because of the identity of the anatomical and cuticular features of petioles attached to stem and those petioles with attached foliage. The fertile material is regarded as part of the same plant because: (1) The anatomy of axes of the fertile specimens is like that of the sterile specimens. (2) A single specimen may contain both sterile Rhodea-type axes and fertile regions. (3) Axes bearing synangia have the same size and patterns of divisions as the sterile foliage. Features that indicate lyginopterid affinities include: (1) Equal forking of the petiole. (2) Presence of fiber bands in the outer cortex and sclerotic nests in the inner part of the cortex. (3) Crowded circular bordered pits on the lateral walls of the metaxylem tracheids. (4) The presence of a small amount of secondary xylem. A variety of structural details of the stem and petiole suggest the genus Heterangium. The phyletic position of the plant that produced Rhodea, Telangium, Telangiopsis, and Heterangium is reviewed in light of such discoveries as the presence of a planated frond that lacks a lamina and the presence of both monolete and trilete microspores in a single synangium.