墨兰的解剖学研究

运用石蜡切片法和扫描电镜技术,对墨兰营养器官和生殖器官进行了研究。结果表明墨兰叶片表面具较厚的角质层。气孔多为四轮列型,分布在下表皮,叶肉没有海绵组织和栅栏组织的分化,但叶尖部和叶中部中脉附近的叶肉细胞常伸长,类似栅栏组织细胞,平行脉,外韧型维管束,在假鳞茎中,维管束散生在基本组织中,根具根被,皮层和维管柱三部分,花被各部分基本结构均相似,唇瓣和合蕊柱的表皮为腺表皮,具花柱道,三心皮雌蕊,一室,侧膜胎座,四合花粉,表面无纹饰,蒴果。     

珍稀植物扇脉杓兰营养器官的解剖学研究

采用石蜡切片技术对扇脉杓兰营养器官的解剖结构进行了研究。结果表明：根状茎的薄壁细胞中含丰富的淀粉粒,维管柱中分布着排列紧凑的周木维管束;根的皮层发达,有的皮层细胞中存在真菌菌丝团,木质部与韧皮部呈辐射状相间排列,根和根状茎的内皮层细胞都形成马蹄形加厚结构。茎的表面分布气孔,皮层面积较小,皮层内部的基本组织发达,外韧维管束散生分布其中,茎和叶上都附有非腺性毛;叶为等面叶,叶肉细胞排列疏松,气孔主要分布于远轴面,略外凸,保卫细胞中含有叶绿体,叶缘处的叶肉组织中含有气腔结构。扇脉杓兰营养器官的这些特征与其荫蔽湿润的生境是相适应的。     

接骨草的显微结构及其绿原酸组织化学定位研究

运用石蜡切片法和荧光显微镜观察法研究了3个不同接骨草(Sambucus chinensis Lindl.)居群营养器官的显微结构及其绿原酸的分布规律。结果表明:(1)接骨草地上茎厚角组织明显,髓部由大小不等的两类薄壁细胞组成,且有单宁细胞分布;地下根状茎厚角组织细胞小,髓部薄壁细胞大小差异不明显,皮层及髓中有油细胞分布。(2)叶片为异面叶,栅栏组织细胞为短柱状,油细胞不明显。(3)绿原酸分布在根状茎皮层部分细胞、茎厚角组织部分细胞及叶片的海绵组织中,以海绵组织中含量最高。研究认为,髓部薄壁细胞大小的差异可作为接骨草的一个鉴别特征;荧光显微镜观察法可迅速准确显示绿原酸的分布;在所研究的3个接骨草居群中,怀化居群的绿原酸含量最高,若以绿原酸为有效成分来采收接骨草,可以只采收叶。     

骆驼蓬属营养器官的旱生结构

对国产骆驼蓬属３种７个地方居群的营养器官内部构造作了对比观察。结果表明：该属植物具有明显的旱生结构,主要特点为：根周皮发达;器官中有同心性异型维管束;茎叶肉质,内有发达的贮水组织,叶栅栏组织发达,呈环栅型、叶片表面积与体积之比较小;茎的皮层、髓部及叶肉组织有大量含晶细胞。     

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。     

墨兰组织培养植株的叶结构和生理特性

墨兰叶肉没有海绵组织和栅栏组织的分化,但在叶的不同部分的叶脉附近叶肉细胞有不同的形态变化。叶尖和叶中部中脉附近的叶肉细胞排列紧密。细胞明显伸长,似栅栏组织,叶基部中 叶肉细胞没有伸长,叶部叶绿体周径大,叶绿素含量高,光合速率亦较高,且Fv/Fm、φPSⅡ和qp均较叶的其他部分高。     

不同耐旱性大麦品种叶片发育的研究

选用耐旱性不同的两个大麦品种作为研究对象,分析其叶片结构的异同。结果表明:两个大麦品种的叶片发育可以分为幼叶萌发期、幼叶抽出期、幼叶生长期和叶片成熟期四个阶段,其中在幼叶萌发期,叶片结构无明显差异。经PAS染色,从幼叶生长期开始,耐旱性弱的Moroc 9-75,含淀粉粒的叶肉细胞少,淀粉粒颗粒小; 耐旱性强的HS 41-1,含淀粉粒的叶肉细胞多,淀粉粒颗粒大。遭受干旱胁迫后,两个品种的植株长势明显较弱,叶片短而窄; 表皮细胞角质层变厚,叶片中叶肉细胞变小,叶肉细胞胞间隙变大,叶肉细胞破裂现象增多; PAS染色反应显示,含淀粉粒的叶肉细胞减少,淀粉粒颗粒变小或基本没有; HS 41-1解体的细胞不如Moroc 9-75多。因此,在光镜下,叶片结构的差异,特别是细胞含有的淀粉粒大小与数量的区别,是植物对水分胁迫的一种适应; 同时叶脉对植物刚性的影响较大。     

海桑和无瓣海桑叶片结构的比较研究

为了探讨外来植物无瓣海桑的潜在危害,采用石蜡切片法对海桑(Sonneratia caseolaris Engl.)、无瓣海桑(S.apetala B.Ham)叶片进行了解剖学研究。实验结果显示,两种植物的叶片均为等面叶;中脉维管束为周韧维管束;具4级侧脉,第1级侧脉为半周韧维管束;成熟叶片叶肉组织具发达的贮水薄壁细胞,具含单宁成分的薄壁细胞,具晶体细胞和石细胞;盐腺由表皮细胞发育而成,可分为3个发育阶段。作为外来植物的无瓣海桑,其中脉维管束具微弱形成层,叶脉维管组织比海桑更发达;贮藏组织中含单宁细胞、晶体细胞较多;栅栏组织含叶绿体多于海桑等特点,使其比海桑对环境具有更大的适应性。因此,无瓣海桑有可能成为入侵植物。     

银杏叶发育过程的解剖结构观察

利用半薄切片、扫描电镜和透射电镜技术,对不同发育时期的银杏叶片解剖结构变化进行连续观察.结果显示:(1)展叶期叶片无栅栏组织和海绵组织分化,细胞排列紧密;展叶后叶肉分化为栅栏组织1~2层,细胞呈长椭球形,海绵组织发达,细胞呈横向排列的椭球形,并形成通气系统;衰老期部分海绵组织细胞变小,并纵向排列,通气系统发达.(2)除叶基和叶缘外,成熟叶片的维管束直径基本相同,维管束鞘发达.(3)早期叶片上表皮有较多气孔分布,展叶后气孔密度迅速降低;下表皮气孔数量较多,但气孔密度随叶片的成熟逐渐下降.(4)叶绿体类囊体在展叶期结构简单,常含1~2个较大淀粉粒;生长期类囊体结构逐渐完善,淀粉粒较少,无嗜锇滴;衰老期类囊体瓦解,嗜锇滴大量累积.     

绞股蓝营养器官中皂苷积累组织的超微结构观察

应用超薄切片和电镜技术观察了绞股蓝营养器官中积累皂苷的叶肉细胞、茎表皮细胞、茎皮层细胞和茎韧皮部细胞的超微结构.结果表明,幼叶叶肉细胞的液泡中具有蛋白体性质的电子致密物;随着叶的发育,叶绿体结构逐渐完善并积累淀粉粒;地上茎表皮细胞的外侧壁增厚,皮层细胞含叶绿体,液泡内有团块状结构;根状茎中的筛管细胞具有囊泡结构,其内的颗粒状内含物可释放至液泡和跨壁运输;韧皮薄壁细胞近细胞壁处具有丰富的细胞质和细胞器.但上述细胞中均未发现与皂苷积累相关的特殊电子致密物.     

台湾独蒜兰假鳞茎显微及超微结构观察

以休眠期的台湾独蒜兰(Pleione formosana)假鳞茎为试材,利用石蜡切片及透射电子显微镜,分别对假鳞茎的5个部位(假鳞茎基部、假鳞茎中部、假鳞茎外侧、假鳞茎与叶芽相接处、假鳞茎与花芽相接处)进行了系统观察分析。结果发现：(1)台湾独蒜兰假鳞茎5个部位均观察到液泡及不同程度液泡化的细胞,表皮细胞覆着有厚厚的蜡质层。(2)台湾独蒜兰假鳞茎基部、中部、外侧细胞中均存在一定的叶绿体,少量线粒体分布在其周围。(3)假鳞茎薄壁细胞中存在淀粉粒及造粉体,且造粉体伴随有形成淀粉粒的现象。(4)假鳞茎基部、中部、外侧及其与花芽相接处的薄壁细胞壁之间有大量胞间连丝,筛管-伴胞复合体与薄壁细胞间也存在胞间连丝,同时细胞间存在不同形状的细胞间隙。研究结果表明,台湾独蒜兰假鳞茎发挥了其作为储水器官、光合作用场所及储存碳水化合物的功能,同时休眠期间主要以共质体途径进行物质的交换与运输。     

Cell type specific expression of a CaMV 35S-GUS gene in transgenic soybean plants

A number of independently derived transgenic soybean plants expressing a chimeric β-glucuronidase (GUS) gene under the control of the 355 CaMV promoter and a nopaline synthase polyadenylation signal were recovered using direct DNA transfer via electric discharge particle acceleration. Expression of GUS in R, plants was localized using thin tissue sections. Many tissue types expressed GUS at various levels. Pericycle cells in root, parenchyma cells in xylem, and phloem tissues of stem and leaf had high levels of enzyme activity. Procambium, phloem, and cortex cells in root, vascular cambium cells in stem, and the majority of cortex cells in leaf midrib, expressed low or no GUS activity. Intermediate levels of GUS activity were detected in leaf mesophyll cells, certain ground tissue cells in stem and leaf midrib, and in trichome and epidermal guard cells. Thus, we conclude that the 35S CaMV promoter is cell-type specific and is developmentally regulated in soybean.     

CHANGES IN STARCH DISTRIBUTION IN THE OVERWINTERING ORGANS OF TYPHA LATIFOLIA (TYPHACEAE)

Histochemical determinations for storage of carbohydrates in rhizomes, roots, and young shoots of Typha latifolia L. (Typhaceae) were conducted during the overwintering period from November to April. Early winter analysis showed that rhizomes and roots contained large amounts of starch (45.03% and 22.80% dry weight, respectively). The major storage tissue was parenchyma of the rhizome central core. From winter into spring a gradual decrease in storage starch in the rhizome and root occurred concurrently with starch accumulation near zones of rapid development in young shoots (buds), but the rhizome retained much starch (27.40% dry weight) into the start of its 2nd yr.     

SHOOT APEX ORGANIZATION AND ORIGIN OF THE RHIZOME-BORNE ROOTS AND THEIR ASSOCIATED GAPS IN DENNSTAEDTIA CICUTARIA

The shoot apex of Dennstaedtia cicutaria consists of three zones—a zone of surface initials, a zone of subsurface initials, and a cup-shaped zone that is subdivided into a peripheral region and central region. A diffuse primary thickening meristem, which is continuous with the peripheral region of the cup-shaped zone, gives rise to a broad cortex. The roots occurring on the rhizomes are initiated very near the shoot apex in the outer derivatives of the primary thickening meristem. The roots that occur on the leaf bases also differentiate from cortical cells. Eventually, those cortical cells situated between the newly formed root apical cell and the rhizome procambium (or leaf trace) differentiate into the procambium of the root trace, thus establishing procambial continuity with that of the rhizome or leaf trace. Parenchymatous root gaps are formed in the rhizome stele and leaf traces when a few of their procambial cells located directly above the juncture of the root trace procambium differentiate into parenchyma. As the rhizome procambium or leaf trace continues to elongate, the parenchyma cells of the gap randomly divide and enlarge, thus extending the gap.     

白鲜营养器官解剖结构及其与白鲜碱的积累关系

应用植物解剖学、组织化学及植物化学方法对白鲜营养器官根、茎、叶的结构及其生物碱的积累进行了研究。结果显示:(1)白鲜根的次生结构以及茎和叶的结构类似一般双子叶植物;白鲜多年生根主要由周皮、次生韧皮部、维管形成层以及次生木质部组成,根次生韧皮部中可见大量的淀粉、草酸钙簇晶、韧皮纤维以及油细胞;茎由表皮、皮层、维管组织和髓组成;叶由表皮、栅栏组织、海绵组织和叶脉组成;在茎和叶初生韧皮部的位置均分布有韧皮纤维,在叶表皮上分布有头状腺毛和非腺毛;在茎和叶紧贴表皮处分布有分泌囊。(2)组织化学分析结果显示:在白鲜多年生根中,生物碱类物质主要分布在周皮、次生韧皮部、维管形成层和木薄壁细胞中;在茎中,生物碱主要分布在表皮、皮层、韧皮部、木薄壁细胞及髓周围薄壁细胞中;在叶中,生物碱主要分布在表皮细胞、叶肉组织和维管组织的薄壁细胞;此外在分泌囊和头状腺毛中亦含有生物碱类物质。(3)植物化学结果显示,秦岭产白鲜根皮/白鲜皮、根木质部、茎和叶中白鲜碱含量分别为0.041%、0.012%、0.004%和0.002%,其中木质部中白鲜碱含量和其他部分地区白鲜皮中白鲜碱含量类似。研究表明,在秦岭产白鲜营养器官中,除根皮/白鲜皮外,在根木质部亦含有大量的白鲜碱,且在茎和叶中亦含有一定的白鲜碱,具有潜在的开发利用价值。     

Anatomy of the vegetative organs and secretory structures of Rhaponticum carthamoides (Asteraceae)

Roots, stems, rhizomes and leaves of Rhaponticum carthamoides (Willd.) Iljin (a Siberian adaptogenic plant, originating from the Altai and Saian Mountains) of different ages were investigated by means of light and electron microscopy. Schizogenous secretory reservoirs occurred in every organ, and were located within the secondary xylem (adventitious roots and rhizome of young plants), at the interface of endodermis/cortical parenchyma (roots and hypocotyl), along phloem and primary xylem (older rhizome), around the vascular bundles (inflorescence stem, petiole and leaf midrib veins) and along phloem (cotyledonary and leaf veins). At the interface of endodermis/inner parenchyma, secretion accumulated in the intercellular spaces prior to the formation of proper epithelial cells. The secretion as observed by transmission electron microscopy comprised three components: soluble (i.e. absent from sections; probably phenolic), insoluble and strongly osmiophilic (probably phenolic) and insoluble, moderately osmiophilic (probably lipidic). Numerous osmiophilic oil droplets, similar to the lipidic secretion inside the reservoirs, local proliferation of rough endoplasmic reticulum and numerous multivesicular bodies characterized epithelial cells in all organs. Leucoplasts (in subterranean organs) with osmiophilic inclusions and peroxisomes with crystalloid inclusions were specific for parenchyma cells. Peltate glandular hairs were formed on leaf blades.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 207–233.