芋营养器官中的草酸钙晶体及其可能的生理作用

利用徒手切片,在光学显微镜下对芋(Colocasia esculenta(L.)Schott)营养器官中晶体的类型和分布进行了观察和研究,并用化学方法对晶体的化学成分进行了鉴定。结果表明,芋营养器官中的晶体为草酸钙结晶体,形态上可以分为针晶和簇晶两大类。含针晶束的异细胞有3种类型:含发射型草酸钙针晶束异细胞(存在于叶片、叶柄、块茎中),含大型草酸钙针晶束异细胞(存在于叶片、叶柄、块茎、块茎皮中),含大量草酸钙针晶的管状异细胞(仅存在于不定根中)。草酸钙针晶也有散乱分布于块茎和不定根中的。草酸钙簇晶在叶片、叶柄、块茎、块茎皮、不定根中均有分布,且叶片、叶柄、块茎皮中的簇晶比块茎和不定根中的尖锐。芋营养器官中的草酸钙晶体很可能是作为一种防御机制,防止动物的取食。     

中国天南星科花粉形态的研究

利用扫描电镜对天南星科Araceae22属28种(除Arum maculatum产自德国外,其余均产自中国) 及菖蒲科Acoraceae 1属2种植物的花粉形态进行了观察。结果显示天南星科花粉形态在科内变异很 大。花粉粒形状从球形、近球形、椭球形到扁球形和橄榄形;萌发孔类型有散孔型、具薄壁区型、环沟型 或无萌发孔;外壁纹饰为小穴状、网状、肋条状、条纹状、疣状、具刺或光滑。主要依据花粉形态方面的证 据探讨了崖角藤属Rhaphidophora、麒麟叶属Epipremnam 、龟背竹属Monstera 3属的属间关系以及犁头尖属Typhonium属下分类中存在的一些问题。     

植物草酸钙晶体的形成和功能

草酸钙晶体在植物中普遍存在,其形成是一种基本的生理过程。总结了目前对草酸钙晶体的生化、结构、形成、调控以及在植物生长发育过程中所起作用等方面的研究进展。     

天南星科的生态地理和起源

本文将天南星科105个属的分布区归纳为12个分布类型和29个亚型,对每一类型的属进行生态地理分析。本科计有88个热带属,占全科的83.8％,是一个热带科。全科有两大分化中心:热带亚洲为属的多样化中心,热带美洲是种的分化中心。根据天南星科各属的生态地理研究,结合到科的系统发育程序,作者得出结论说:天南星科的原始类群在晚白垩纪时起源于亚洲大陆南缘,即欧亚古陆的亚洲南缘地带的水域生态环境。     

天南星科的生态地理和起源

本文将天南星科105个属的分布区归纳为12个分布类型和29个亚型,对每一类型的属进行生态地理分析。本科计有88个热带属,占全科的83．8％,是一个热带科。全科有两大分化中心：热带亚洲为属的多样化中心,热带美洲是种的分化中心。根据天南星科各属的生态地理研究,结合到科的系统发育程序,作者得出结论说：天南星科的原始类群在晚白垩纪时起源于亚洲大陆南缘,即欧亚古陆的亚洲南缘地带的水域生态环境。     

六种犁头属植物（天南星科）的核型研究

报道了6种8个居群犁头尖属（Typhonium Schott）植物的核型,其结果如下：（1）独角莲（T.gigan-teum）北京居群2n＝4x=52=44m 7sm 1st;（2）鞭檐犁头（T.flagelliforme）金平居群2n=3x=24=3m 9sm(4SAT) 12st,河内居群2n＝4x=32=7m 20st 4sm 1t;（3）单籽犁头（T.calcicolum)西畴居群2n=4x=52=21sm 23m(5SAT) 8st;（4）犁头尖（T.blumei）重庆居群2n=4x=52=40m(1SAT) 12sm(3SAT);(5)马蹄犁头（T.roxburgii）个旧居群2n＝2x=18=8sm 10m(2SAT)。其中鞭檐犁头尖2n=24、32,金慈菇2n＝28均为首次报道,同时分析讨论了本属植物染色体基数和倍性的多样性及其可能的原始基数。     

天南星科分类系统的沿革

天南星科 Araceae是一个世界性的大科 ,计1 0 5属约 3 5 0 0余种 [1]。单子叶植物 ,与浮萍科组成 1个目。在中国植物志排在第 1 3卷 ,第 2分册 [2 ]。其分布区跨越从赤道带到寒温带的各个生态地带 ,散布于新旧世界的各大陆块 ,仅在一些海岛地区和南美大陆有较多空白点 [3 ] 。中国有 2 6属 2 0 0余种[4 ] ,种属数量都不多 ,但不少属如 Pinellia、Arisaema、Remasatia和 Colocasia等都是以中国为分化中心的。中国最早有关天南星科植物的记载 ,始于本草书籍。西汉时期的“神农本草经”就记载了菖蒲(Acorus calamus) ,虎掌 (Pinellia pedati…     

植物含晶细胞的结构与功能

文章就植物含晶细胞的组分、分布、形态、存在形式和功能的研究进展作了介绍。     

斑龙芋属(天南星科)及近缘属植物的叶表皮形态

光镜、电镜下观察了天南星科天南星族下斑龙芋属2个种及近缘属13个种植物的叶表皮形态特征。实验结果显示,4属植物的叶表皮组成及其形态特征较相似,属间不存在明显差异,但某些特征在种间存在差异,可作为种的鉴别特征。叶表皮特征支持将单籽犁头尖和昆明犁头尖两个种合并为一个种。15个种的气孔器均具有2个副卫细胞,Stebbins andKhush认为这是气孔器类型中较具2个以上副卫细胞更进化的一种类型,而天南星科大多数族的气孔器都具有2个以上的副卫细胞,这也证明了天南星族是天南星科较进化的族。     

我国13种天南星科作物上的芋花叶病毒

用直接负染和免疫电镜方法从我国浙江省(杭州、奉化、温州等地)、上海、北京、福建、湖南等地的13种天南星科大田作物:芋(Colocasia esadenta)、魔芋(Amorphophallus sinesis)、药用植物:半夏(Pinellia ternata)、掌叶半夏(P. cordata)、盾叶半夏(P. pedatisecta)以及观赏植物:马蹄莲(Zantedeschia aethiopica)、海芋(Alocasia macrorrhiza)、象耳芋(Colocasia gigantea)、台果芋(Syngonium podophygum)、黄金葛(Scindapsus aureus)、广东万年青(Aglaonema modestum)、花叶芋(Caladium bicolar)、剑叶喜林芋(Philodendium oxycadium)上均检测到芋花叶病毒(Dasheen mosaicvirus, DMV)。在免疫吸附-免疫修饰电镜水平上,该病毒与DMV抗血清和PVY抗血清均有强阳性反应。在人工接种条件下,DMV各分离物均不侵染烟草等非天南星科供试植物,但接种天南星科指示植物Philodendr…     

The Occurrence, Type and Location of Calcium Oxalate Crystals in the Leaves of Fourteen Species of Araceae

The occurrence, type and location of calcium oxalate crystalsin the leaves of 14 species belonging to the family Araceaewere studied by light microscopy. The Pizzolato test and theRubeanic acid-silver nitrate test, used to chemically identifyand locate the crystals in cross sections of laminae, showedthe presence of four types of crystals: druses, raphides, prismaticsand crystal sand. Styloids were not observed in any of the species.Crystals identified as calcium oxalate were observed in eachtissue layer of the leaf blade, druses occurring more frequentlyin the palisade mesophyll layers, raphides more often in thespongy mesophyll. Prismatics were sparse, occurring in the mesophyllof only two species. Specialized spindle-shaped crystal idioblasts,located in the spongy mesophyll in all cases, were observedin seven of the 14 aroids. Crystal sand and variations in crystalforms were most frequently observed to be calcium compoundsother than calcium oxalate. Crystals, calcium oxalate, idioblasts, Araceae     

Calcium Oxalate Crystals in Developing Seeds of Soybean

Young developing soybean seeds contain relatively large amountsof calcium oxalate (CaOx) monohydrate crystals. A test for Caand CaOx indicated that Ca deposits and crystals initially occurredin the funiculus, where a single vascular bundle enters theseed. Crystals formed in the integuments until the embryo enlargedenough to crush the inner portion of the inner integument. Crystalsthen appeared in the developing cotyledon tissues and embryoaxis. All crystals formed in cell vacuoles. Dense bodies andmembrane complexes were evident in the funiculus. In the innerintegument, cell vacuoles assumed the shape of the future crystals.This presumed predetermined crystal mould is reported here forthe first time for soybean seeds. As crystals in each tissuenear maturity, a wall forms around each crystal. This intracellularcrystal wall becomes contiguous with the cell wall. Integumentcrystals remain visible until the enlarging embryo crushes theinteguments; the crystals then disappear. A related study revealedthat the highest percent of oxalate by dry mass was reachedin the developing +16 d (post-fertilization) seeds, and thendecreased during late seed maturation. At +60 d, CaOx formationand disappearance are an integral part of developing soybeanseeds. Our results suggest that Ca deposits and crystals functionallyserve as Ca storage for the rapidly enlarging embryos. The oxalate,derived from one or more possible metabolic pathways, couldbe involved in seed storage protein synthesis. Copyright 2001Annals of Botany Company Calcium, crystals, development, Glycine max, ovule, oxalate, seed, soybean     

Histochemical Localization of Calcium Oxalate Crystals in Starch Grains of Yams (Dioscorea)

The bulbils and/or tubers of seven species of yams (Dioscorea)were examined for crystal content using light microscopy andhistochemistry. Calcium oxalate crystals in the form of raphide bundles werelocalized in the parenchymatous tissues. Within starch grains,crystals of various shapes and sizes were observed. The variationin shape and sizes of the intra-amylar crystals could be exploitedfor taxonomic purposes. Calcium oxalate crystals appear to serve a storage functionin these starch grains. Yams, Dioscorea, raphides, oxalate crystals, histochemistry     

Mucilage Cells, Calcium Oxalate Crystals and Soluble Calcium in Opuntia ficus-indica

The subcellular location of soluble calcium in parenchymatousand mucilage cells of Opuntia ficus-indica was determined histochemically.Soluble calcium was observed in crystal chambers containingcalcium oxalate on the membrane of the vesicles. Calcium wasalso present in the plasmalemma, in plasmodesmata, in cell walls,in mitochondria and in the vacuoles. Especially marked was thepresence of soluble calcium in vesicles free or fused with theplasmalemma. Little free calcium was observed in other cellcompartments. In the calcium economy of tissues the location of soluble calciumand the transport of calcium to and from mucilage cells to parenchymatouscells and calcium oxalate idioblasts will play a role. Chelationof calcium by mucilage or oxalate, which depends on pH, ionicstrength, etc., will be important in this respect. Opuntia ficus-indica, calcium oxalate, mucilage cells, transport of calcium     

Calcium Oxalate Crystals in Eucalypt Ectomycorrhizae: Morphochemical Characterization

Ectomycorrhizal fungi are ubiquitous in forest ecosystems, benefitting plants principally by increasing the uptake of water and nutrients such as calcium from the soil. Previous work has demonstrated accumulation of crystallites in eucalypt ectomycorrhizas, but detailed morphological and chemical characterization of these crystals has not been performed. In this work, cross sections of acetic acid-treated and cleared ectomycorrhizal fragments were visualized by polarized light microscopy to evaluate the location of crystals within cortical root cells. Ectomycorrhizal sections were also observed by scanning electron microscopy (SEM) coupled with energy dispersive x-ray (EDS) microprobe analysis. The predominant forms of crystals were crystal sand (granules) and concretions. Calcium, carbon and oxygen were detected by EDS as constituent elements and similar elemental profiles were observed between both crystal morphologies. All analyzed crystalline structures were characterized as calcium oxalate crystals. This is the first report of the stoichiometry and morphology of crystals occurring in eucalypt ectomycorrhizas in tropical soils. The data corroborates the role of ectomycorrhizae in the uptake and accumulation of calcium in the form of calcium oxalate crystals in hybrid eucalypt plants.     

犁头尖属及其近缘属植物(天南星科)的花粉形态

利用扫描电镜对犁头尖属（Typhonium Schott）及其近缘属共18种植物的花粉进行研究,其中,8种为首次报道,11种为我国特有。结果表明：天南星族4属植物花粉形态基本一致,无萌发孔,无覆盖层,具刺,但各个种在花粉粒大小,刺长,刺的开关,刺的密度,刺基部直径和刺间纹饰方面差别较大,可以作为种的区别特征之一。花粉形态特征支持天南星族为本科最进化类群的观点。花粉粒刺间具颗粒为半夏属（Pinellia Tenore）植物花粉的显著特征,花粉形态特征不支持将单籽犁头尖（T,calcicolum C.Y.Wues H.Li et al.）和昆明犁头尖（T,kunmingense H,Li）合并。西南犁头尖（T.omeiense H.Li）的花粉粒非常小,认为是较进化的种。犁头尖属内种间的花粉形态差异较大,甚至大于属间的差异,或许该属的系统分类需要作较大的变动,这与Susanne利用cpDNA片段的所提结果基本一致。     

Structures and functions of adventitious roots in species of the genus Philodendron Schott (Araceae)

We discuss here the anatomical variations of the arrangements and compositions of stele types observed in different roots types in four populations of the three species of Philodendron as probable adaptations to their habitats. Terrestrial individuals of P. corcovadense have cylindrical steles while rupicolous individuals have lobate steles with dispersed internal cortical parenchyma. The Philodendron species sampled showed polyarch structures. The crampon roots of P. oblongum and anchor roots of P. cordatum show medullated protosteles, with the former species having a reduced pith with sclerified parenchyma cells while the latter has a wide pith and parenchyma cells with only slightly thickened walls. The feeder roots of P. cordatum also show a medullated protostele—although a central vessel is present until approximately 60 cm from the apex that later disappears, forming a parenchymatous pith. We conclude that the different root types reflect adaptations of the subgenera Philodendron and Meconostigma to their different habits and habitats, such as in P. corcovadense, where the roots of rupicolous individuals have lobate steles while the roots of the terrestrial plants have cylindrical steles.     

腐植酸对高温胁迫下掌叶半夏生长生理特性及块茎次生代谢的影响

采用不同浓度(0、20、40、60、80、100mg/L)腐植酸(HA)叶面喷施处理,通过盆栽实验分析了HA对高温胁迫下掌叶半夏幼苗生长生理指标及次生代谢的调控效应。结果显示:(1)各浓度HA处理均可不同程度地促进高温胁迫下掌叶半夏的生长发育,且以80mg/L HA处理下其块茎鲜重(6.990 5g/株)、叶柄鲜重(1.755 4g/株)及总叶绿素含量(19.961 3mg/g)最高,较对照分别显著提高21.25%、118.5%和37.19%。(2)当HA处理浓度为60mg/L时,掌叶半夏幼苗叶片中可溶性糖、可溶性蛋白含量均最高,分别比对照显著提高66.67%、40.91%;叶片抗氧化酶(SOD、POD)活性达到最大值,MDA含量降至最低,SOD、POD活性分别比对照显著提高818.98%和48.2%,MDA含量较对照显著降低62.08%;且块茎中鸟苷含量较高,比对照显著提高52.94%。(3)当叶面喷施80mg/L HA时,掌叶半夏幼苗叶片中游离脯氨酸含量和块茎中总生物碱、总有机酸、腺苷的含量均最高,分别比对照显著提高169.63%、27.19%、42.32%、96.23%。研究表明,适宜浓度HA处理可显著提高高温胁迫下掌叶半夏幼苗叶片内抗氧化酶(SOD、POD)的活性及渗透调节物质(可溶性糖、可溶性蛋白、游离脯氨酸)含量,以及块茎中次生代谢产物(总生物碱、总有机酸、鸟苷和腺苷)的含量,有效减轻夏季高温对掌叶半夏幼苗叶片的伤害、延缓衰老、提高其幼苗抗热性,促进生长、延长生长期。