Structure and Development of Stomata on the Vegetative and Floral Organs of Some Amaryllidaceae

The structure and development of stomata in 10 Amaryllidaceousmembers are described. The study is made on the leaves and floralorgans of Amaryllis belladona, Crinum asiaticum, C. bulbispermum,C. latifolium, C. pratense, Pancratium sp., Polianthes tuberosa,and Zephyranthes atamsco, and on leaves of Agave sp. and Curculigoorchioides. In most of the organs of the different plants studiedmore than one type of stoma occur, even on the same surface.However, the stomata are largely anomocytic in Amaryllis, Crinum,Pancratium, Polianthes, and Zephyranthes, but they are tetracyticin Agave and Curculigo. An increase in the number of subsidiarycells in teracytic, tricytic, paracytic, and stomata with onesubsidiary cell has been noted. It may be due to wall formationin the subsidiary cells or by the neighbouring perigenes assumingtheir form. The range of variation in different types of stomatain each organ has been studied. Abnormal features such as juxtaposedor superimposed contiguous stomata, connections between guardcells of nearby stomata, transformation of meristemoids intoepidermal cells are observed. The development of different typesof stomata in different organs of the same plant is perigenous.The systematic position of different genera is discussed inlight of the present findings. A method of preparing epidermalimprints by the use of Depex, a mounting medium, and white ofan egg is also described.     

Structure and Development of Stomata on the Vegetative and Floral Organs in Some Members of Caesalpiniaceae

The structure and development of stomata in 19 species of thefamily Caesalpiniaceae are described. The study is mostly confinedto the leaves, but observations have also been made on othervegetative and floral organs of some species Stomata may beparacytic, anisocytic, anomocytic, and with one subsidiary cell.Occasionally a stoma is diacytic, cyclocytic, or actinocytic.Different types occur individually or may be found side by sideeven on the same surface of an organ. The most prevalent typein all the genera is paracytic except in Caesalpima where itis anomocytic. The development of an anomocytic stoma is perigenous,but those with subsidiary cells are largely mesogenous; rarelyparacytic stomata are mesoperigenous. In spite of diversityof stomata, different types of stomata have similar patternsof development in different organs of the same plant. The presentinvestigation also indicates that the inconstancy of stomatain the family is due to (a) their diversity and (b) an increasein the number of subsidiary cells either by their division orby the neighbouring perigenes becoming subsidiary cell-like.     

Epidermal Structure and Ontogeny of Stomata in Vegetative and Reproductive Organs of Ephedra and Gnetum

The epidermal structure and development of stomata in vegetativeand reproductive organs of Ephedra foliata and Gnetum ula isdescribed. The epidermal cells are polygonal, isodiametric,or elongated with thick or thin straight, arched, or slightlysinuous anticlinal walls. The cuticle is thin or thick. Papilla-likeunicellular outgrowths are present in Ephedra foliata. The maturestomata are orientated parallel to the longitudinal axes orirregularly. The mature stomata are anomocytic, paracytic, witha single subsidiary cell, cyclocytic, and actinocytic. Arresteddevelopment, contiguous stomata, and stomata with aborted guardcells have been observed. The ontogeny of stomata on differentorgans of these two plants is typically haplocheilic or perigenousbut the stomatal apparatus varies from organ to organ.     

气孔在四季秋海棠营养器官和繁殖器官上的发育及相关性分析

主要观察了气孔在四季秋海棠营养器官和繁殖器官上的分布和发育情况,并分别对叶片和翅上气孔簇大小、气孔簇密度等指标的相关性进行了研究、结果表明:在叶片的下表皮、雌花和雄花的花被片、苞片、小苞片和翅上有气孔分布,而在茎、花梗上却未见气孔分布.叶片下表皮和翅上气孔通常成簇分布.在叶片的下表皮,气孔簇大小与气孔簇密度呈显著的负相关(P<0.05);气孔簇密度与叶片长度呈极显著的负相关(P<0.01).而翅上的气孔簇密度、气孔簇大小与子房长度无显著相关性(P>0.05).在四季秋海棠中,不同器官表皮的气孔簇大小是不同的,这可能与生理功能的不同有关.     

The Development of Stomata in Vegetative and Reproductive Organs ofBupleurum tenue Buch.-Ham. ex D. Don

InBupleurum tenue stomata have been observed on leaf, stem,stalk of compound umbel and umbellet, bract of involucre andinvolucel, pedicel of flower, both surfaces of petal, outerepidermis of pericarp, and the stylopodium. Their developmentis of the syndetocheilic type in vegetative as well as the reproductiveorgans. In the stylopodium the stomata are anomocytic whilein the rest of the organs they are anisocytic.     

Development of Stomata in some Ophioglossum Species

This paper deals with the development of stomata in vegetativeand reproductive organs of five species of Ophioglossum. Thestomata are typically hap-locheilic or perigenous from organto organ. Superimposed twin stomata, stoma with aborted guardcells and persistent stomatal initial are seen. The presentstudies support the view of foliar nature of the spike of Ophioglossum.     

Structure and Development of Stomata in Some Labiatae

The structure and ontogeny of stomata have been studied in 33species of the Labiatae. The mature stomata are diacytic, transitionalbetween paracytic and diacytic, and anomocytic. The anomocyticstomata are haplocheilic or perigenous. The diacytic and thetransitional type of stomata are syndetocheilic or mesogenousas the two subsidiary cells and a pair of guard cells arisefrom the same meristemoid. The diacytic and the transitionalstomata are formed through three successive mitotic divisions.Abnormal stomata with single guard cells, arrested developments,and contiguous stomata have been observed. Contiguous stomataare formed either from two adjacently placed meristemoids orare the result of spatial readjustment during maturation ofthe leaf.     

Structure and Histochemistry of Stomata and Epidermal Cells in Five Species of Polypodiaceae

The epidermal structure of the five species of ferns, Arthromeriswallichiana (Spr.) Ching., Drymoglossum piloselloides (Prest.),Drynaria quercifolia (L.) J. Smith, Lepisorus nudus (Hook.)Ching. and Pyrrosia nuda (Gies.) Ching., has been investigated.Fifteen types of stomatal structures have been identified ofwhich copolo-desmocytic and coperi-desmocytic are new types.Four more possible stomatal structures: ccpolo-peri-, codesmo-polo-,codesmo-peri- and duplodesmocytic, are suggested. Localizationof starch, insoluble polysaccharides, protein and lipids hasbeen examined histochemically in the guard cells, subsidiarycells and epidermal cells. In Drynaria starch plastids and plastidscontaining both starch and protein are present in guard cells.Starch plastids are present in the subsidiary cells of all speciesexcept in Arthromeris, whereas, they are present in epidermalcells of only Drymoglossum and Lepisorus. Granular or amorphousinsoluble polysaccharides (other than starch) are present inguard cells of all the species, in the subsidiary cells of Arthromeris,Drynaria and Pyrrosia, and in the epidermal cells of Pyrrosia.Except in Pyrrosia lipids are present in the guard cells. Subsidiarycells of Drynaria and the epidermal cells of Arthromeris andDrynaria show lipid bodies. The presence of plasmodesmata andectodesmata is demonstrated in the epidermal cells of Drymoglossum.     

Structure and Development of Stomata in Some Leptosporangiate Ferns

The structure and development of stomata are described for 17species of leptosporangiate ferns. In these species the maturestomata are anomocytic, diacytic, Pyrrosia(applied), tetracytic,suspended, or floating type. Stomata are present on both surfacesof floating as well as sub merged leaves of Azolla and Marsilea.In a few species twin stomata, arrested development, and persistentstomatal initials are present Floating stomata result from disintegrationof the anticlinal suspending wall in Pleopeltis, and by detachmentand displacement in Azolla pinnata. The development of stomatais haplocheilic, syndetocheilic, or syndetohaplocheilic. InCyathea spinulosa the guard cell nuclei divide amitoticallyand the resulting two daughter nuclei occupy the opposite polesof the guard cells     

Epidermal Structure and Development of Stomata in some Annonaceae

Epidermal structure and development of stomata are studied in20 species of the Annonaceae. Epidermal cells are polygonalor irregular in outline, isodiametnc or elongated with straight,arched, or sinuous anticlinal walls. Cuticular striations radiatingfrom guard cells or hair bases are noticed. Four types of trichomesand secretory cells are seen. The mature stomata are paracyticwith 2–6 subsidiary cells, non-contiguous at both poles,or contiguous at one or both the poles. The increase in numberof subsidiary cells is due to their divisions. Contiguous stomata,arrested development, single guard cell, and degeneration ofguard cells are observed. The development is either syndetocheilicor mesogenous.     

银线草营养器官结构及主要成分的组织化学定位

采用植物解剖学和组织化学定位方法研究银线草营养器官的显微结构和萜类、黄酮类化合物在营养器官中的分布规律.结果表明:银线草的根皮层细胞排列整齐,细胞间隙较小,韧皮部狭窄;茎皮层细胞也排列整齐,在韧皮部外方包围有多层束状纤维;叶为异面叶,栅栏组织和海绵组织分化明显,叶片上、下表皮均无毛被,气孔器多为不规则型.组织化学定位结果显示萜类和黄酮类化合物分布在根的皮层、茎的皮层和韧皮部细胞中.     

The Structure and Development of the Reproductive Organs and Carposporophyte in two British Species of Gelidium

The structure and development of the reproductive organs andcarposporophyte are described for two British species of Gelidium,G. latifolium (Grev.) Born. & Thur. and G. pulchellum (Turn.)Kütz. The gonimoblast does not develop directly from theunchanged carpogonium, as was thought by Kylin, but a swollenmultinucleate cell of irregular outline is formed first, eitherfrom the carpogonium alone, or by the fusion of the carpogoniumand certain neighbouring cells; the gonimoblast develops fromlong, non-septate processes of this multi-nucleate cell. Thesignificance of the fusion of the carpogonium and certain vegetativecells is discussed in relation to the various definitions ofthe auxiliary cell which have been proposed. It is concludedthat an auxiliary cell does not occur in Gelidium.     

空心莲子草营养器官结构与三萜皂苷动态积累的关系

采用组织化学定位、显微制片技术和三萜皂苷定量分析方法对空心莲子草营养器官结构与三萜皂苷类物质积累关系进行了研究。结果表明：空心莲子草宿根、根状茎、茎和叶中均有三萜皂苷物质的积累,叶和根状茎内含量十分丰富。在相同采收期内含量依次为：叶＞根状茎＞根＞茎,叶中主要积累于栅栏组织细胞内。空心莲子草的根和根状茎横切面均属于异常结构,具有成同心环状排列的三生维管束。在宿根和根状茎的次生韧皮部、栓内层、三生韧皮部和结合组织内均有三萜皂苷的分布,三生结构在宿根和根状茎中占有主要地位,是三萜皂苷积累的主要场所。在不同采收期内叶、根状茎和根中三萜皂苷的积累趋势基本一致,均随生长期的增加而递增。空心莲子草茎的横切面由表皮、皮层、维管束和髓腔组成,仅部分皮层细胞和初生韧皮部内有三萜皂苷分布。     

气孔运动中的活性氧信号

大量研究证明活性氧(ROS)在气孔运动中起信号分子的作用。保卫细胞中ROS的产生依赖于特定的酶,其中NADPH氧化酶组分RBOH已得到深入研究,并已证实其参与生物与非生物胁迫反应。植物激素包括脱落酸(ABA)、水杨酸(SA)、乙烯、生长素及细胞分裂素等,它们均通过ROS的介导来调控气孔运动。生物胁迫(如毒性细菌和真菌)也会调控气孔运动。ROS参与这些调控过程。保卫细胞中存在多层次对ROS产生及其作用的调节,抗氧化活性物质和ROS敏感蛋白(如蛋白激酶和磷酸酶)均可传递ROS信号并调节气孔运动。ROS对离子通道调节的证据也越来越多。保卫细胞由于可通过ROS整合复杂的信号途径,已成为研究植物ROS信号转导过程的良好模式系统。     

Vegetative Proliferation of Floral Spikelets in British Grasses

Proliferation of spikelets in grasses other than those raceswhich are habitually viviparous is reviewed, and the factorsinducing proliferation experimentally in Cynosurus cristatusand other species are discussed. It is concluded that the evidencefavours the hypothesis that in the viviparous races a considerablygreater minimal concentration of the putative flowering hormoneis required for flower induction than for culm initiation, whereasin the seminiferous races this difference is not so great. Inthe viviparous races, the threshold for flower initiation israrely exceeded so that perfect flowers appear only occasionally,whilst in the normally seminiferous races, the conditions ariseonly rarely where an amount of hormone is produced sufficientto initiate culms but insufficient to promote flowering.     

地枫皮营养器官解剖结构特征及其叶片结构的生态适应性

为了明确地枫皮的结构特征及其在石灰岩山顶和山腰疏林间两种环境下生长的叶片解剖结构的差异,本研究采用石蜡切片和半薄切片对地枫皮营养器官进行解剖观察并评价了叶片结构对不同生态环境的响应。结果表明:地枫皮根中次生维管组织发达,木射线和韧皮射线明显。老茎的次生构造中,皮层贮藏物质丰富,内有大的石细胞群,韧皮射线和木射线明显;而髓细胞内含有大量晶簇和少量单晶。在叶片横切面观上,叶为异面叶,表皮细胞一层,上表皮无气孔分布,主脉中薄壁细胞中分散有石细胞。叶片解剖结构显示,随海拔高度上升,地枫皮趋向于旱生植物的特点,其主要表现在叶片表皮细胞外壁角质层加厚,栅海比增加、海绵组织排列由紧密变疏松。另外,根皮、茎皮和叶肉中都分布有大量油细胞。     

Ontogeny of Stomata on the Foliar and Floral Or{dot}gans of some Species of Crotalaria L.

The structure and development of stomata in eight species ofCrotalaria belonging to the family Papilionaceae are described.The study is mostly confined to the leaves but it has also beenmade on the floral organs of C. mysorensis, C. retusa, C. sericea,and C. triquetra. The stomata may be paracytic, anisocytic,anomocytic, diacytic, or with one subsidiary cell. The differenttypes occur individually or they are placed side by side evenon the same surface of an organ. In general the paracytic typeis by far the commonest, followed by anisocytic and anomocyticones. Diacytic stomata and those with one subsidiary cell arerelatively rare. Different types of stomata in various organsof the same plant develop mesogenously. The present investigationalso indicates that the inconstancy of stomata in the familyis due to (a) their diversity and (b) an increase in the numberof subsidiary cells either by their division or by the neighbouringperigenes becoming subsidiary cell-like.     

Floral Development of Three Maesa Species, with Special Emphasis on the Position of the Genus within Primulales

Floral development of three Maesa Forssk. species, M. argenteaWall., M. japonica(Thunb.) Moritzi ex Zoll. and M. perlarius(Lour.)Merr., was studied with a scanning electron microscope. Thedistinctive floral features of the genus, such as presence oftwo persistent bracteoles, perigynous flowers and many-seededfruits, have been used to discuss the systematic position ofthe genus within Primulales. In addition, the development ofcommon stamen-petal primordia, the number, arrangement and positionof ovules and the shape of the anthers provide evidence in favourof placing Maesa in a separate family, Maesaceae, as suggestedby Anderberg and Ståhl (Canadian Journal of Botany, 73:1699–1730, 1995). Copyright 2000 Annals of Botany Company Primulales, Maesa argentea Wall., Maesa japonica(Thunb.) Moritzi ex Zoll., Maesa perlarius(Lour.) Merr., floral ontogeny, SEM     

Development of Stomata in Equisetum

Hitherto published accounts of the development of stomata inEquisetum are conflicting about the sequence of divisions andabout the formation of a sub-stomatal cell from a meristemoid.The present study of the development of stomata in a speciesidentified as E. ramosissimum subspecies ramosissimum supportsthe observations of Strasburger (1867) and Pant and Mehra (1964)on the basis of sections cut in various planes through internodesof the plant.