Single Guard Cell Research Articles

Structure and development of stomata on the fruit wall ofCalotropis procera (Ait.) R. Br.

The epidermal characters ofCalotropis procera (Ait.) R. Br. fruit have been investigated. Stomata being present only in the outer epidermis of the epicarp, the fruit is called exostomatic. Only the perigenous type of stomata are present on the fruit wall. Stomatal abnormalities like single guard cell, aborted guard cell, contiguous stomata, paired stomata, unequal guard cells, stomatal connection with distinct tube and stomata with large meristemoid are observed. Inner epidermis shows a ‘parquetry pattern’ of its cells. The outer epidermis is hairy but the inner epidermis is atrichomal and nonstomatiferous. The cuticle is thick, with numerous striations.

The interrelationship of growth substances and stomatal characters inGossypium hirsutum var H-777

Various types of stomatal abnormalities like persistent stomatal initials, single guard cells, degenerated guard cells and contiguous stomata with contiguity in different directions were recorded due to the treatment of different growth substances. Growth substances also altered the stomatal size, epidermal cell size, stomatal frequency, index and length-to-breadth ratio. It seems that the effect of these substances starts from the stomatal ontogeny and continue up to the last phase of development leading to such variations.

Microtubules and morphogenesis in stomata of the water fernAzolla: An unusual mode of guard cell and pore development

A mature stomate of the water fernAzolla consists of a single apparently unspecialized annular guard cell (GC) with two nuclei surrounding an elongated pore aligned longitudinally in the leaf. During development, the guard mother cell develops a preprophase band (PPB) of microtubules (MTs) oriented transverse to the leaf axis. This is followed by a cell plate which fuses with the parental walls at the PPB site. Subsequently only the central part of the cell plate is consolidated, while the parts to either side become perforated and tenuous and may disperse completely, forming a single composite GC.

Structure and development of stomata in some Acanthaceae

Structure and development of stomata have been studied in 14 genera and 22 species of the Acanthaceae. The leaves ofNeuracanthus sphaerostachys are hypostomatic while those of other species investigated are amphistomatic. The stomata are typically diacytic, monocyclic or incompletely or completely amphicyclic being surrounded by 2,3 or 4 subsidiary cells and mesogenous in development having been formed as a result of three, four or five successive mitotic divisions of the meristemoid. Arrested developments, single guard cells with or without pore, contiguous stomata and aborted guard cells are the common abnormalities noticed.

Influence of Morphactin on Leaf Morphology and Stomatal Apparatus of Vigna radiata (L.) Wilczek

Abstract The present paper reports the effects of morphactin on leaf morphology and stomatal apparatus of Vigna radiata. Morphactin treated plants showed fusion of leaflets resulting in the formation of a simple leaf with various modifications or amplification giving rise to tetra-, penta-, and multifoliate leaves simulating palmate leaves. The area of leaflets and petiole size of treated plants were considerably reduced. Morphactin also changed the form of stomata with paracytic, anisocytic and anomocytic types observed. A reduction in frequency of stomata, size of epidermal cells, trichomes and stomatal pore were common with an increase in stomatal size on the abaxial surface. Aberrations such as contiguous stomata, stomatal degeneration and stomata having a single guard cell were noted. Since the action of morphactin is in the direction of reducing transpiration, the application of this substance may be helpful in cultivation of crops exposed to periodic dry conditions.

Taxonomic bearing of stomatal structure and development in some Polemoniales

AbstractThe structure and development of stomata in 27 genera and 53 species belonging to the families of the order Polemoniales are described. Nine stomatal types noticed are: anomocytic, anisocytic, actinocytic, staurocytic, diacytic, paracytic, tetracytic, transitional between paracytic and diacytic and stomata with a single subsidiary cell. Three modes of stomatal development observed are: mesogenous, perigenous and mesoperigenous. Stomatal abnormalities seen are: stomata with a single guard cell, arrested development and variously oriented contiguous stomata. The stomata varies in form, number, orientation and arrangement of the subsidiary and also the surrounding cells in different organs of a plant. On the basis of stomatal studies, the splitting of Polemoniales into Polemoniales Boraginales and Solanales is justified. The separation of Ehretiaceae from Boraginaceae is not justifiable.

Structure and development of normal and abnormal stomata in the seedlings of some Cruciferae

The structure and ontogeny of normal and abnormal stomata in the seedlings of 16 species of the Cruciferae have been presented. The mature stomata are anomocytic, paracytic, anisocytic, helicocytic and with a single subsidiary cell. The ontogeny of the anisocytic, paracytic, helicocytic and stoma with a single subsidiary cell conforms to the syndetocheilic or mesogenous, while that of anomocytic to haplocheilic or perigenous type. Several types of aberrant stomatal formations such as: single guard cell; contiguoas single-guard cells; contiguous stomatal; degeneration of guard cell/s; persistert stomatal cell; amitotic division of guard mother cell nucleus followed by pore formation; stoma with double pores; binucleate guard cell; division of guard cell; incomplete stoma with unequal guard cells; cytoplasmic connection; ring-shaped division of guard mother cell and uncommon wall thickening have been noticed. Aberrant stomatal developments are naturally occurring and not induced.

Structure and ontogeny of stomata in some Gentianaceae and Menyanthaceae complex

AbstractThe structure and development of stomata are described in the leaves of 8 genera and 12 species of the Gentianaceae Menyanthaceae complex. Out of the twelve species studied vegetative and floral organs are investigated in five. The epidermal cells are either squarish, rectangular or polygonal and isodiametric or elongated or irregular in outline. In Gentianaceae the mature stomata are anomocytic, actinocytic, anisocytic, paracytic, diacytic and stoma with a single subsidiary cell. While they are mostly anomocytic very rarely actinocytic and paracytic in Menyanthaceae. In Gentianaceae the ontogeny of anisocytic, paracytic, diacytic and stoma with a single subsidiary cell is mesogenous, while that of anomocytic and actinocytic perigenous. Anomocytic, actinocytic and paracytic stomata of Nymphoides indica conforms to the perigenous type of development. Abnormalities such as arrested development; cytoplasmic connection between adjacent stomata; single guard cell; contiguous stomata and division of one or both the guard cells of a stoma are noticed. Guard cells of Exacum pedunculatum contain needle like crystals of calcium oxalate. The present observations support the separation of the Gentianaceae and Menyanthaceae.

Fluorescence Properties of Guard Cell Chloroplasts

The presence of chloroplasts in guard cells from leaf epidermis, coleoptile, flowers, and albino portions of variegated leaves was established by incident fluorescence microscopy, thus confirming the notion that guard cell chloroplasts are remarkably conserved. Room temperature emission spectra from a few chloroplasts in a single guard cell of Vicia faba showed one major peak at around 683 nanometers. Low-temperature (77 K) emission spectra from peels of albino portions of Chlorophytum comosum leaves and from mesophyll chloroplasts of green parts of the same leaves showed major peaks at around 687 and 733 nanometers, peaks usually attributed to photosystem II and photosystem I pigment systems, respectively. Spectra of peels of V. faba leaves showed similar peaks. However, fluorescence microscopy revealed that the Vicia peels, as well as those from Allium cepa and Tulipa sp., were contaminated with non-guard cell chloroplasts which were practically undetectable under bright field illumination. These observations pose restrictions on the use of epidermal peels as a source of isolated guard cell chloroplasts. Studies on the 3-(3,4-dichlorophenyl)-1,1-dimethylurea-sensitive variable fluorescence kinetics of uncontaminated epidermal peels of C. comosum indicated that guard cell chloroplasts operate a normal, photosystem II-dependent, linear electron transport. The above properties in combination with their reported inability to fix CO(2) photosynthetically may render the guard cell chloroplasts optimally suited to supply the reducing and high-energy phosphate equivalents needed to sustain active ion transport during stomatal opening in daylight.

Development of a new coulter counter system: Measurement of the volume, internal conductivity, and dielectric breakdown voltage of a single guard cell protoplast ofVicia faba

A new Coulter Counter is described which measures on single microscopic cells the volume, membrane breakdown voltage, and the underestimation of volume after breakdown, this last parameter reflecting in part the internal conductivity of the cells. The system requires very few cells for measurement and does not require the population to be normally distributed in volume or free of debris from the preparation of the cells. The new development is to apply a voltage ramp across a Coulter orifice through which a particle flows. A differential dual orifice system is used to reduce the magnitude of the amplified ramp signal to that of the signal produced by the particle in the presence of a DC voltage across the orifice. Breakdown is detected by an underestimation of the cell volume once a critical voltage across the cell membrane has been established. Measurements made on protoplasts isolated from guard ceils ofVicia faba with a mean volume of 1800 μm3 reveal a breakdown voltage of 1 V and an average volume underestimation of about 30% after breakdown. Variations in this underestimation reflect the different internal structure of the protoplasts in terms of the size and number of nonconducting compartments. Different stages of vacuole development exist in each preparation. The breakdown voltage of 1 V suggests that only one membrane breaks down and that the electromechanical properties of these protoplast membranes are similar to other cell systems, when the pulse length dependence of the breakdown voltage is taken into consideration.

Epidermal studies in some Indian cultivars of Bougainvilleas

AbstractEpidermal studies in fifteen Indian cultivars of Bougainvilleas are described. The epidermal cells are polygonal isodiametric, or elongated with thick straight arched or slightly sinuous walls. Parallel culticular striations are radiating from guard cells. The mature stomata are anomocytic, paracytic and with a single subsidiary cell. The abnormal types noticed are: single guard cells with or without pores, arrested development, variously oriented contiguous stomata, cytoplasmic connections between nearby stomata and epidermal or subsidiary cells, and persistent stomatal cells. The development of anomocytic stomata is perigenous while that of the other types is mesogenous. Fifteen cultivars of Bougainvilleas are separated on the basis of bract colour, stomatal frequency and index per unit area.

The Affinities of Costesia and Neosharpiella and Notes on the Gigaspermaceae (Musci)

The genera Costesia Ther. and Neosharpiella Robins. & Delg. are- transferred from the Funariaceae to the Gigaspermaceae. Neosharpiella turgida (Mitt.) Robins. & Delg. is reported for the first time from Chile. The morphology of the six genera currently placed in the Gigaspermaceae is compared and generic inter-relationships discussed. SEM micrographs of the spores of four genera are given. In the revised sense presented, the Gigaspermaceae have a widely scattered, predominantly Southern Hemispheric distribution. Nomenclatural notes on several taxa are appended and several lectotypes are proposed. In the course of revisionary study on the Funariaceae, I have had occasion to examine material of the Central and South American genus Neosharpiella Robins. & Delg. and the South American genus Costesia Ther., as well as type material of most of the species currently placed in the Gigaspermaceae. This paper presents evidence that Neosharpiella and Costesia are improperly placed within the Funariaceae and that they are better placed in the Gigaspermaceae sensu Brotherus. The Funariaceae and the Gigaspermaceae were both placed in the Funariales by Broth- erus (1924). The Funariaceae may be characterized by the following set of characters: 1. annual or biennial habit; 2. erect, little-branched stems (very rarely prostrate and more or less rhizomatous); 3. leaf cells thin-walled and without thickened corners; 4. costae well developed, very rarely absent; 5. usually autoicous sexual condition; 6. perigonial pa- raphyses with globose terminal cells; 7. capsules various, with stomata enclosed by a single guard cell and a slit-like pore; and 8. spores relatively large, though usually less than 50 gm in diameter. The Gigaspermaceae, on the other hand, may be characterized by: 1. apparently perennial habit; 2. prostrate, rhizomatous stems giving rise to erect branches; 3. leaf cells thin- or firm-walled, often undulate in outline and usually with thickened corners; 4. costae variously developed; 5. usually synoicous or paroicous sexual condition; 6. perigonial paraphyses filiform, without inflated terminal cells; 7. capsules gymnostomous, with stomata enclosed by two guard cells (rarely imperfectly formed); and 8. spores large, usually in excess of 50 gm diam. Collectively, Costesia and Neosharpiella are known from South America and Mexico where they grow as weeds on soil. Although appearing acrocarpous, the plants exhibit an unusual growth habit similar to that of the unrelated genus Drummondia and to which neither the term acrocarpous nor pleurocarpous can be applied without qualification. They proliferate by fragile, nearly hyaline rhizomes that give rise to the more visible erect branches. The apices of the leafy shoots give rise to sporophytes with exserted, broadly obovoid capsules resembling those of some Physcomitrium species, but which have a characteristic strongly wrinkled appearance when dry. Costesia was described by Theriot (1917) on the basis of two Chilean specimens col- lected by N. Costes in 1915. To my knowledge, the sole representative of the genus, C. 007-2745/80/466--476$1.35/0

Air pollutants and epidermal traits in Ricinus communis L.

Eighty-five samples of leaves of Ricinus communis L. (Euphorbiaceae) representing five populations—four collected from healthy, and one from polluted, environments—were studied to establish the relationship between environmental pollution and foliar epidermal features. The data obtained were analysed statistically. Stomatal frequency per square millimetre and the percentage of abnormal stomata (single guard cell or both the guard cells aborted) on both the upper and the lower epidermis showed a marked increase in plants growing ni polluted areas. One or two per cent of stomata on the lower epidermis also showed a slight decrease in size. A correlation between idioblast frequency and pollution was also observed. Scanning electron microscopic studies of the foliar surface revealed that stomatal openings were larger and cuticular striations more conspicuous in leaves of polluted populations than in those of healthy ones.

Morphogenetic effects of various growth substances on the cotyledonary stomata of brinjal and tomato

The effect of different growth substances on the development of normal and abnormal stomata are presented. Anomocytic, paracytic, anisocytic and stoma with a single subsidiary cell are observed. Abnormal developments like persistent stomatal cells, degeneration of guard cells, unusual thickening, unequal guard cells, single guard cells and size and shape of the pore are noticed in various growth substances. The growth substances also affect the stomatal frequency, stomatal index, epidermal frequency and size of guard and epidermal cells in both the plants. The highest meristematic activity is found in MOR 100 ppm in brinjal and in GA 25 ppm in tomato. The largest size of stomata is found in COL 25 ppm in brinjal and in MH 50 ppm in tomato. The same growth substance responds differently in the two plants.

Structure, ontogeny and taxonomic significance of trichomes and stomata in some Capparidaceae

AbstractThe present work embodies epidermal structure, structure and ontogeny of stomata in five genera embracing sixteen species of the Capparidaceae namely Cleome (8 species) Capparis (5 species), Cadaba (1 species), Crataeva (1 species) and Maerua (1 species). The epidermal cells are polygonal, isodiametric or elongated arranged irregularly, with evenly or unevenly thickened, sinuous, straight or arched anticlinal walls. Two main types of trichomes: glandular (four types) and eglandular (five types) are noticed. The stomatal types include cyclocytic, triacytic, staurocytic, tetracytic, anomocytic, anisocytic, paracytic and with a single subsidiary cell. The ontogeny of stomata with a single subsidiary cell is perigenous or mesoperigenous, of paracytic mesoperigenous or mesogenous, of anisocytic is mesoperigenous or mesogenous, while that of the other types is perigenous. Abnormalities observed are: single guard cell; aborted guard cells; complete or incomplete division of guard cells; contiguous stomata; giant stomata and cytoplasmic connections. The present observations do not support the separation of Cleomaceae from the Capparidaceae.

THE CUTICLE OF DREPANOPHYCUS SPINAEFORMIS, A LONG‐RANGING DEVONIAN LYCOPOD FROM NEW YORK AND EASTERN CANADA

The presence of paracytic stomata and paired guard cells on specimens presumed to be Drepanophycus spinaeformis Göppert from eastern Canada and New York State supports the conclusion of Banks and Grierson that the species is not a reliable index of Lower Devonian strata. The interpretation of stomatal morphology demonstrates that the species lived in Early, Middle, and Late Devonian time and that slender specimens are distinct from zosterophylls such as Sawdonia that had anomocytic stomata and a single guard cell. Knowledge of the stomata also permits a reinterpretation of the stomatal apparatus as first described by Lang. Siegenian specimens of the genus apparently represent the oldest occurrence of paired guard cells and of paracytic stomata.

Structure, Ontogeny and Taxonomic Significance of Stomata in Some Cucurbitaceae

AbstractStomatal structure, ontogeny in vegetative and floral organs of 9 genera and 12 species of Cucurbitaceae are described. The stomatal types conform to aperigenous, monoperigenous, diperigenous, hemipara‐mesoperigenous and para‐mesoperigenous types of Fryns‐Claessens & Van Cotthem (1973). Stomatal abnormalities such as contiguous stomata, single guard cells with or without pore, one and a half stomata, degeneration of one or both the guard cells, cytoplasmic connections between guard cells of neighbouring stomata and a guard cell of a stoma and an adjacent epidermal cell, and division of guard cells are described. Stomata index, frequency of stomata, epidermal cells, size of guard and epidermal cells and organwise distribution of stomata are given. Stomatal studies does not support the view that the Cucurbitaceae are related to the Passifloraceae. The inclusion of 9 genera and 12 species studied in the tribe Cucumerineae is justified.

Action of growth regulators on the cotyledonary stomata ofCucumis sativus L.: Structure and ontogeny

Anomocytic stomata and stomata with single subsidiary cells are commonly observed Sometimes a stoma appears anisocytic. Double cytoplasmic connections between nearby stomata and division of guard cells with persistent or degenerating nuclei are seen in GA. One or more divisions of guard cells, displaced guard cells and single guard cells with or without pore are noticed in SUC. Formation of single guard cells is a common feature in TIBA. Paracytic stomata, one and a half stomata and persistent stomatal initials are seen in SUL. COUM seems to be not inhibitory inCucumis sativus. In COL stomata with unequal guard cells, unequal stomatal cells with thickening in between but without intervening pore, stoma with double pores, persistent stomatal initials which may be solitary or in groups with varying shapes and with one or two nuclei of different shapes are noticed. The growth regulators affect the frequency of stomata, epidermal cells; stomatal index; size of guard and epidermal cells.

Studies in Stomata of Ginger, Turmeric and Mango Ginger

Summary Ontogeny, structure and histochemistry of stomata in Zingiber officinale Rosc. (ginger), Curcuma domestica V alet . (turmeric) and C. amada R oxb . (mango ginger) belonging to the family Zingiberaceae have been described. Diperigenous, tetraperigenous and anisocytic stomata are present. Abnormalities like a stoma with a single guard cell and a degenerated stomatal cell are rare. Division of lateral subsidiary cells is observed in all the three species. Calcium oxylate crystals are present in the guard cells and subsidiary cells of mature leaves. A special type of polar wall thickening in the stomata is observed. The presence of lipid bodies as an aid in the identification of subsidiary cells is also indicated.

Structure and Development of Stomata in Some Labiatae

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