沉香叶解剖结构的研究

通过石蜡切片法,光学显微镜观察,研究了沉香叶的解剖结构。结果表明,沉香叶为典型的异面叶,但具有许多旱生特征。表皮由一层排列紧密的形状不规则的表皮细胞组成,细胞外壁角质膜较厚,上表皮角质膜较下表皮的厚3.48μm,下表皮上零星分布着单细胞表皮毛,气孔类型为无规则型,仅分布在下表皮上,微下陷;叶肉组织发达,其间分布着较多的长方晶体,其长轴与表皮垂直;栅栏组织由1～2层圆柱形细胞组成,其外层细胞转化为异细胞,栅栏组织∶海面组织为1∶3.5,下表皮内具有1～2层由异细胞组成的下皮层;主脉发达,有异细胞组成的维管束鞘,具内生韧皮部;叶内具有发达的木质部外纤维。以上特征反映出植物结构与环境的统一性。     

稀有植物香果树叶解剖结构的研究

通过石蜡切片法制片,光学显微镜观察,Motic显微摄像,研究了香果树（Emmenopterys henryi Oliv.）的叶形态解剖结构。结果表明,香果树叶为典型异面叶;表皮由一层紧密的形状不规则的表皮细胞组成,细胞外壁角质膜较薄;气孔类型为平列型,仅分布于下表皮;下表皮上零星分布着多细胞表皮毛;叶肉组织发达,栅栏组织由1~2层排列整齐的圆柱形细胞构成;海绵组织枝状分布,排列极为疏松,细胞间隙大;叶脉主脉发达;上述特征反映出植物结构与环境的统一性。     

风毛菊属3种植物叶的解剖结构比较

采用石蜡切片法对分布于祁连山海拔5 000 m左右流石滩上菊科风毛菊属水母雪兔子（Saussurea medusa Maxim）、鼠曲雪兔子（Saussurea gnaphalodes (Royle) Sch.）、红叶雪兔子（Saussurea paxiana Diels.）3种植物叶片的解剖结构进行了比较研究,结果表明：叶片表皮细胞均为单层,上下表皮都有气孔分布,气孔不下陷;角质层较厚,叶表面均被单列细胞的表皮毛。3种植物均为异面叶;叶肉栅栏组织较发达,通常由2～3层细胞组成,但栅栏组织细胞排列较疏松;海绵组织存在大量的细胞间隙;叶肉中通气组织发达,且均有不规则裂生性气腔。叶脉维管束中韧皮部都具有异细胞存在。这些共同特征是3种植物对高山地区缺氧、低温、强辐射等自然条件长期适应的结果。但是,3种植物在叶片的外部形态特征、叶肉栅栏组织细胞的特点、维管束发育程度、内分泌结构、不规则裂生气腔等方面又存在明显的不同,表现出3种植物对环境的适应也是存在差异的。     

桂花叶解剖结构的研究

通过石蜡切片法制片,光学显微镜观察,研究了桂花叶的形态解剖结构。结果表明,桂花叶为典型的异面叶,表皮由1层排列紧密的形状不规则的表皮细胞构成,细胞外壁角质膜较厚,气孔只分布于下表皮。表皮上被有腺毛,腺毛及其周围排列整齐的表皮细胞形成环式结构。叶肉组织发达,栅栏组织由2～4层排列整齐的圆柱形细胞构成。叶肉中分布有少分枝或不分枝的石细胞,其细胞长轴与表皮垂直。叶脉结构较为复杂,主脉发达。上述特征与复杂多变的环境条件相适应。     

贵州省常见唇形科植物茎和叶比较解剖学研究

运用石蜡切片技术对贵州省40种常见唇形科植物茎、叶进行了比较解剖学研究。结果显示:(1)40种唇形科植物具有典型的双子叶植物茎、叶的解剖特征,茎由表皮、皮层和维管柱组成,棱角表皮下具有发达的厚角组织,棱角处厚角组织内方的维管组织明显较其它部分发达;茎横切面形态主要有3种类型,维管束排列也主要呈现3种方式。(2)叶片由表皮、叶肉和叶脉三部分组成,均为异面叶,栅栏组织细胞1~3层,少部分物种叶脉腹面隆起;绝大部分常见物种主脉明显较侧脉发达,但也有少部分主脉、侧脉大小相近;主脉中维管束大多为1个,形态包括月牙形、半圆形、圆形,少量物种主脉具有多维管束;表皮毛由1~3个细胞组成,表皮毛的形态多为锥状,少为杆状。研究表明,唇形科植物茎、叶的显微结构无论在属内还是在种间都存在差异,在探讨唇形科种的分类地位及其物种鉴定时都具备参考价值,但却难以作为分类鉴定的决定性特征。     

中国木兰科植物的叶结构及其油细胞的比较解剖学研究

利用组织透明法、石蜡切片法及薄切片法对木兰科10属82种1亚种植物叶片的结构和油细胞的 分布密度、结构及其在叶肉中的分布进行了比较研究。鹅掌楸亚科和木兰亚科在叶结构上的主要区别是：鹅掌楸亚科两种植物叶的部分下表皮细胞乳突状,且整个细胞外壁只形成一个乳突,而在木兰亚科植物中有单列多细胞或单细胞的表皮毛,却未发现乳突;鹅掌楸亚科植物叶主脉维管组织环分隔呈束状,且其外包被的纤维也排列成束状,而木兰亚科的80种1亚种植物中,叶主脉维管组织连成轮状,其外面也由一圈连续的纤维环所包围。从而支持木兰科中木兰亚科和鹅掌楸亚科两个亚科的划分。并且,从叶主脉的演化趋势来看,鹅掌楸亚科较木兰亚科进化。另外,木莲属植物叶片的结构与木兰属具有明显差异,因而进一步证明木莲属是不同于木兰属的一个独立的属。油细胞是木兰科植物叶片解剖的显著特征,在叶肉中的分布可划分为3种类型：(A)主要分布于栅栏组织;(B)主要分布于海绵组织;(c)均匀散布于整个叶肉中。油细胞的大小及其在叶中的分布与叶厚、栅栏组织层数、栅栏组织与海绵组织厚度间的比值以及下皮层的有无、表皮毛的类型、叶脉的结构等特征相结合,可作为属、甚至种的鉴别特征。     

中国假鹰爪属和皂帽花属植物叶的形态结构及其分类学意义

利用扫描电镜技术、叶片离析法和石蜡切片法研究了假鹰爪属Desmos 4种植物和皂帽花属Dasy-maschalon 3种植物叶片的形态结构。结果表明：假鹰爪属植物叶片近轴面表皮具大型球状含晶簇细胞和不含晶簇的表皮细胞两种类型,远轴面表皮细胞均具一较小的晶簇;叶肉组织明显分化为栅栏组织细胞和海绵组织细胞,油细胞分布于第2层的栅栏组织和海绵组织内,单位毫米叶宽油细胞数为4～6个;主脉维管组织被薄壁细胞分隔成束状。皂帽花属植物叶片近轴面表皮细胞形状相同,均具一晶簇,远轴面表皮细胞的晶簇和近轴面表皮细胞的晶簇相似;靠近上、下表皮的叶肉组织均分化为栅栏组织细胞,在两层栅栏组织细胞之间分化为一至几层海绵组织细胞,油细胞分布于海绵组织内,单位毫米叶宽油细胞数为2～3个;主脉维管组织形成连续的环状。由此可见两属叶的结构具有明显的差异,因而支持假鹰爪属和皂帽花属为两个独立属的观点。     

玉龙雪山不同海拔草血竭叶片形态与解剖结构的比较研究

采用常规石蜡制片技术和显微观察方法,对生长于滇西北玉龙雪山3 000~4 600m之间9个不同海拔高度的草血竭(Polygonum paleaceum)叶片表型及解剖结构进行比较研究,其目的是揭示该植物对不同海拔环境条件的响应特征,进而探讨植物对全球气候变化的生态适应性。结果显示:(1)草血竭叶片长度、宽度、长宽比均与海拔呈显著负相关关系,其降幅分别达84.64%、74.87%和37.50%。(2)草血竭叶片为异面叶,由表皮、叶肉、叶脉三部分组成;表皮细胞单层,角质层厚;叶肉的栅栏组织具2层或3层细胞;叶脉中的维管束呈1圈不连续的环状排列。(3)叶片厚度、栅栏组织厚度、海绵组织厚度、主脉厚度、以及主脉中维管束的长度和宽度均与海拔呈显著正相关关系,增幅分别达38.32%、47.30%、47.39%、156.46%、173.51%及337.42%;上表皮厚度、下表皮厚度、叶片紧密度、叶片疏松度、栅海比以及维管束的个数与海拔梯度之间的相关性则均不显著。研究表明,随着海拔升高,草血竭叶片形态结构的改变主要是有利于植物降低蒸腾,增强储水性和提高光合效率。     

川西高原4种苹果属植物叶片解剖结构与其抗旱性分析

采用常规石蜡制片法和NaOCl法,对川西高原地区4种苹果属植物叶片的解剖结构特征进行了观察,并选取叶片厚度、上下表皮角质层厚度、上下表皮细胞厚度、栅栏组织厚度等14项抗旱性相关指标进行测定,运用方差分析、主成分分析和隶属函数法对4种苹果属植物的抗旱性进行了分析与综合评价。结果显示:(1)4种苹果属植物叶片上下表皮外均附有角质层,表皮细胞排列紧密,上表皮细胞明显大于下表皮细胞,其中变叶海棠的角质层厚度和表皮细胞厚度均较大;气孔均只分布在下表皮,其中花叶海棠的气孔密度最大,花叶海棠和湖北海棠的气孔长、宽最小;栅栏组织由2~3层排列紧密的栅栏细胞组成,海绵组织细胞排列疏松,细胞间隙大,其中山荆子的栅栏组织厚度、栅海比和叶片结构紧密度最大;主脉均为外韧维管束,其中湖北海棠维管束厚度最大,且皮层中有时出现含晶细胞。(2)所选14项指标中除下表皮角质层厚度外,其余13项指标在4个树种间差异显著,经主成分分析筛选出上表皮角质层厚度、下表皮细胞厚度、栅栏组织厚度等8项指标作为4种苹果属植物抗旱性综合评价的代表性指标。(3)隶属函数法分析结果表明,4种苹果属植物抗旱能力大小顺序为:变叶海棠山荆子花叶海棠湖北海棠。     

山茶属6种植物叶片解剖结构的耐热性分析

通过石蜡切片观察6种山茶属(Camellia)植物叶片的解剖结构，应用聚类分析、相关性分析对叶片组织结构相关指标进行筛选，进一步采用隶属函数综合评价6种山茶属植物的耐热性。结果表明，6种山茶属植物的叶片均为异面叶，上下表皮均由一层排列紧密的细胞组成，叶肉组织中含有结晶体和不规则的石细胞，栅栏组织由1～3层长圆柱状细胞组成，含有大量叶绿体。影响6种山茶属植物耐热性的主要指标为叶片总厚度、栅栏组织/海绵组织、角质层厚度、组织疏松度。6种山茶属植物耐热性由强到弱依次为大果南山茶(C. semiserrata var. magnocarpa)、莽山红山茶(C. mongshanica)、石果红山茶(C. mairei var. lapidea)、长尾毛蕊茶(C. caudata)、东南山茶(C. edithae)、红皮糙果茶(C. crapnelliana)；按耐热性可分为3类，大果南山茶为耐热型，莽山红山茶为中耐热型，其他4种为低耐热型。     

葛(豆科)叶的解剖学研究

利用光学显微镜和扫描电镜观察了葛(Pueraria lobata)叶的解剖学特征。结果表明,葛叶片的上、下表皮都只有一层表皮细胞,上表皮比下表皮厚。上、下表皮都有腺毛和非腺毛。气孔主要分布在下表皮,下表皮的气孔密度为(261±17)mm-2,上表皮只有(6±3)mm-2。叶肉由两层栅栏组织细胞和一层海绵组织细胞构成。叶肉细胞中有丰富的叶绿体。在栅栏组织和海绵组织之间有一层平行于叶脉的薄壁细胞。叶脉中含有大量的草酸钙晶体。葛叶的这些形态特征与其喜阳、耐旱的特点相适应。     

TrnL-trnF sequence data imply paraphyly of Aquilaria and Gyrinops (Thymelaeaceae) and provide new perspectives for agarwood identification

The genera Aquilaria and Gyrinops (Thymelaeaceae, Malvales) are well known for the production of agarwood which is a highly wanted forest product of substantial economic value. The taxonomic status of Aquilaria and Gyrinops as separate genera is doubted as they are only distinguished by the number of stamens. We investigated their status by conducting phylogenetic analyses of DNA sequences from the plastid trnL-trnF spacer. Control of international trade of agarwood is currently hampered by the failure of traditional methods such as microscopy to identify samples to species level. We therefore evaluated the potential of molecular identification of agarwood by searching for species- and region-specific plastid DNA polymorphisms. DNA sequences were obtained from 31 Thymelaeaceae accessions encompassing 20 different species in six genera. Aquilaria and Gyrinops appear to be paraphyletic. Success in sequencing wood samples demonstrates that molecular markers provide new perspectives for agarwood identification.     

龙苍沟国家森林公园7种花楸属植物的叶解剖特征及其环境适应性

采用石蜡切片法对四川省龙苍沟国家森林公园内7种花楸属（Sorbus）植物的叶解剖特征进行研究,探究其结构特征与生境的相关性。结果显示：7种植物的叶片均为典型的背腹叶;叶片厚度介于108.16~208.21 μm,种间差异极显著（P<0.01）;上表皮厚度均大于下表皮厚度,且复叶物种的下表皮细胞均有乳突;栅栏组织由1~2层细胞构成,仅多对西康花楸（S. prattii var. aestivalis）的栅海比（栅栏组织与海绵组织的厚度比）为1.93,其余6种植物的栅海比均小于1;中脉维管束均呈心型,为典型的外韧型维管束,种间中脉突起度存在极显著差异（P<0.01）。各解剖结构中,上、下表皮可塑性最大,在生境中具有较强的潜在适应能力;中脉可塑性最小,整体结构较为稳定。栅栏组织、海绵组织和中脉组织是7种植物中种间差异最大的解剖结构。叶解剖结构与生境因子的相关性分析表明,栅栏组织厚度、栅海比和紧密度与年降水量、最暖季降水和海拔正相关（P<0.05）,与季节性温差负相关（P<0.05）;中脉直径和突起度与季节性温差呈正相关（P<0.01）,与年降水量、最暖季降水和海拔正相关负相关（P<0.05）。叶解剖结构性状的适应性变化,体现了7种花楸属植物在龙苍沟国家森林公园的生存策略。     

Sesquiterpenoids in two different kinds of agarwood

Sesquiterpenoids of an agarwood originating from Aquilaria agallocha and of the other kind of agarwood (Aquilaria sp.; probably Aquilaria malaccensis) were investigated by a combination of GLC and GC/MS. The differences in sesquiterpene composition between the two kinds of agarwood are discussed.     

Leaf anatomical studies of Chamaecrista subsect. Baseophyllum (Leguminosae, Caesalpinioideae): new evidence for the up-ranking of the varieties to the species level

This study aims to determine whether morphoanatomical characters of the leaves of the species of Chamaecrista sect. Absus subsection Baseophyllum could be used to support an up-ranking of C. cytisoides varieties to the species level as previously defined by molecular studies. The significance of anatomical adaptive strategies to arid environments is also discussed. Standard light microscopy techniques and histochemical tests were used for both morphoanatomical and histochemical characterization of the leaves. All the species studied share a single-layered epidermis, actinodromous–camptodromous–brochidodromous type of venation, vascular bundles surrounded by layers of fibers bounded externally by a sheath of cells containing solitary crystals, enlarged tracheids at the vein endings, vascular petiole/rachis tissue with a parenchymatous pith, accessory vascular bundles, mucilage idioblasts and hypodermis in the mesophyll, colleters, and non-secretory trichomes. The position and type of stomata, type of mesophyll, number of palisade and spongy parenchyma layers, position of mucilage idioblasts in the mesophyll, and the number of accessory vascular bundles of petiole/rachis provided useful characters for discriminating the eight species of the subsect. Baseophyllum. Histochemical tests reveal the presence of total polysaccharides, pectins, mucilage and phenolic compounds in the idioblasts. Other xeromorphic characters such as thickened outer periclinal cell walls, compact mesophyll, mucilage idioblasts and hypodermis in the mesophyll may help enable the studied species to survive in exposed sunny areas.     

Structural Adaptation of the Leaf Mesophyll to Shading

Structural characteristics of the mesophyll were studied in five boreal grass species experiencing a wide range of light and water supply conditions. Quantitative indices of the palisade and spongy mesophyll tissues (cell and chloroplast sizes, the number of chloroplasts per cell, the total cell and chloroplast surface area per unit leaf surface area) were determined in leaves of each of the species. The cell surface area and the cell volume in spongy mesophyll were determined with a novel method based on stereological analysis of cell projections. An important role of spongy parenchyma in the photosynthetic apparatus was demonstrated. In leaves of the species studied, the spongy parenchyma constituted about 50% of the total volume and 40% of the total surface area of mesophyll cells. The proportion of the palisade to spongy mesophyll tissues varied with plant species and growth conditions. In a xerophyte Genista tinctoria, the total cell volume, cell abundance, and the total surface area of cells and chloroplasts were 30–40% larger in the palisade than in the spongy mesophyll. In contrast, in a shade-loving species Veronica chamaedris, the spongy mesophyll was 1.5–2 times more developed than the palisade mesophyll. In mesophyte species grown under high light conditions, the cell abundance and the total cell surface area were 10–20% greater in the palisade mesophyll than in the spongy parenchyma. In shaded habitats, these indices were similar in the palisade and spongy mesophyll or were 10–20% lower in the palisade mesophyll. In mesophytes, CO₂ conductance of the spongy mesophyll accounted for about 50% of the total mesophyll conductance, as calculated from the structural characteristics, with the mesophyll CO₂ conductance increasing with leaf shading.     

遮荫对南美蟛蜞菊、蟛蜞菊及其自然杂交种叶片显微结构及叶绿体超微结构的影响

利用JSM-6360LV型扫描电镜和JEM-1010型透射电镜,观察了南美蟛蜞菊、蟛蜞菊及其自然杂交种新近成熟和老熟叶片的解剖结构及叶绿体超微结构。结果表明:遮荫后该杂交种与其亲本新近成熟叶片均表现为上下表皮气孔密度、叶片总厚度及上下表皮厚度、栅栏组织、海绵组织厚度减小,叶绿体肿胀变形,基粒片层垛叠程度增加,淀粉粒增多变大;遮荫后杂交种老熟叶片总厚度及上表皮、栅栏组织、海绵组织厚度增加,入侵种的下表皮厚度及本地种的上表皮厚度增加,叶绿体超微结构在遮荫后均出现严重损伤,基粒片层类囊体结构边缘溶解等。说明三种蟛蜞菊属物种及各物种不同叶龄叶片对弱光条件的响应存在差异;杂交种叶片显微及超微结构在不同光照下的变化介于亲本之间,对遮荫环境能较好适应。     

湖南安息香属植物的叶片比较解剖学研究

利用光学显微镜和扫描电镜对湖南产安息香属10种植物叶表皮微形态和解剖结构进行了观察和测量。结果表明:(1)表皮均由单层细胞构成,细胞形状为多边形和无规则形,垂周壁式样为平直、弓形、波状;(2)气孔器大小及密度在种间的差异明显;(3)气孔外拱盖内缘主要为波状和浅波状,气孔器外围角质纹饰以越南安息香的鸟巢状和栓叶安息香的碗状为显著区别特征;(4)老鸹铃、垂珠花和白花龙的气孔器保卫细胞两极有"T"形加厚;(5)栓叶安息香和大果安息香叶上表皮由大型细胞组成;(6)叶肉分化为栅栏组织和海绵组织,二者的厚度及比值在种间有明显的差异,其中越南安息香栅栏组织分化为2层;(7)大果安息香和芬芳安息香的主脉维管组织构成一圈封闭的环状结构,而其他种则为开放的半圆形结构;(8)叶片及主脉的厚度在种间差异明显。安息香属植物的表皮微形态及解剖结构特征比较稳定,可作为种间鉴定和分类的重要依据。     

Compartmentation in Vicia faba Leaves: I. Kinetics of C in the Tissues following Pulse Labeling

Leaflets of Vicia faba were pulse-labeled with ¹⁴CO₂ to follow the subsequent movement of photosynthate between leaf tissues. Samples were taken during a ¹²CO₂ chase, quick frozen, freeze-substituted, and embedded in methacrylate. Paradermal sections provided tissue samples consisting only of upper epidermis, palisade parenchyma, spongy parenchyma and veins, spongy parenchyma, or lower epidermis. Most CO₂ fixation occurred in the palisade parenchyma, but its ¹⁴C content declined rapidly after labeling. Concomitant with the decline of activity in the palisade parenchyma, there was an increase in activity in the spongy parenchyma and upper epidermis and a slow increase in the lower epidermis. Activity in the palisade parenchyma and spongy parenchyma eventually reached similar levels and remained constant. Tissue samples containing veins were consistently the most radioactive, and activity in those samples showed a decline. Very little change occurred in the insoluble fraction from any tissue. The results support previous assumptions regarding the pathway of assimilate transport to the veins, and demonstrate the rapidity of such transport. Sucrose is apparently the principal mobile compound.