scholarly journals The effect of cadmium on growth of vegetative thallus and development of generative organs of Chara vulgaris L. after short time of cultivation

2014 ◽  
Vol 66 (1) ◽  
pp. 67-72 ◽  
Author(s):  
Aleksandra Gosek ◽  
Maria Kwiatkowska ◽  
Robert Duszyński
Keyword(s):  
Main Axis ◽  
Cadmium Ions ◽  
Chara Vulgaris ◽  
Lateral Branches ◽  
Short Time ◽  
Number Of Cells ◽  
Generative Organs

The effect of cadmium ions in two different concentrations (10<sup>-8</sup>M i 10<sup>-6</sup>M) on vegetative thallus, male (antheridia) and femele (oogonia) generative organs of <em>Chara vulgaris</em> L. was investigated. After 9 days of growth in a presence of cadmium the number of lateral branches decreased and the lengths of internodes of the main axis and pleuridia became shortened. The increase in oospores volume and decrease in antheridial volume (both total and internal) after 3, 7 and 9 days of cultivation were observed. The productivity of antheridium measured by the number of antheridial filaments and number of cells within filament is also lower in plants cultivated with cadmium in comparison with control ones.

scholarly journals Effect of GA3, IAA and their mixtures on the formation and development of cell systems in the vegetative and generative thallus of Chara vulgaris L.

2014 ◽  
Vol 60 (3-4) ◽  
pp. 313-326 ◽  
Author(s):  
Maria Kwiatkowska ◽  
Aleksandra Gosek ◽  
Mirosław Godlewski
Keyword(s):  
Inhibitory Effect ◽  
Main Axis ◽  
Stimulatory Action ◽  
Cell Systems ◽  
Low Concentration ◽  
Chara Vulgaris ◽  
Vegetative Part ◽  
Lateral Branches ◽  
High Level ◽  
Generative Organs

In concentrations ranging from 10<sup>-7</sup> to 10<sup>-5</sup> M IAA strongly stimulates the growth of the main axis and pleuridia internodal cells, while it does not affect the number of lateral branches and generative organs. In the higher concentrations it reduces the number of spermatozoids in the antheridium. In the same concentration range, GA<sub>3</sub>, inhibits the growth of the main axis and pleuridia internodal cells, does not affect the number of lateral branches, increases the number of antheridia and increases the number of forming spermatozoids. Incubation in mixture of both regulators has shown that: a) IAA eliminates the inhibitory effect of GA<sub>3</sub> on the growth of internodal cells of the main axis and its stimulatory action is slightly weakened by GA<sub>3</sub>, b) IAA in a concentration of 10<sup>-5</sup> M along with a low concentration of GA<sub>3</sub>, (10<sup>-7</sup>) increases the number of main axis lateral branches. The conclusion is drawn that the growth of the vegetative part of the thallus is more intense when auxin predominates, but generative development requires a high level of gibberellin.

scholarly journals Comparative study of the vegetative and generative organs in pear varieties

2006 ◽  
Vol 12 (3) ◽  
Author(s):  
P. Dremák ◽  
G. Kocsisné Molnár
Keyword(s):  
Comparative Study ◽  
Relative Frequency ◽  
Main Axis ◽  
Point Of View ◽  
Lateral Branches ◽  
Generative Organs

An assortment of 17 pear varieties was examined in 2006 at Keszthely, Department of Horticulture, Georgicon Faculty of Agriculture, Veszprem University. The selected varieties were planted in 1980, grafted on seedling rootstock and represented the majority of existing pear plantations in Hungary. The main objective was the determination of suitability of the most important varieties for the purpose of intensive growing technologies even when grafted on vigorous seedling rootstock. The most important growing and fruiting characteristics of the varieties have been assessed and evaluated from the point of view of productivity. We stated that the relations of the trunk or the main axis to the lateral branches and fruiting structures are all subject to varietal effects and are valuable indices of the growing character. The quotient of the diameters of trunk and branch should be around 0.3-0.4, and the relative frequency of fruiting structures (Dárda, nyárs, vessző) meaning the ability of branching and regeneration associated with accurate pruning policies are decisive from the point of view of promising success.

scholarly journals The effect of light factor on the development of thallus and generative organs in Chara vulgaris L.

2014 ◽  
Vol 49 (4) ◽  
pp. 397-407 ◽  
Author(s):  
Janusz Maszewski
Keyword(s):  
Mitotic Activity ◽  
Axenic Culture ◽  
Light Period ◽  
Continuous Illumination ◽  
Chara Vulgaris ◽  
The Moment ◽  
Almost All ◽  
Effect Of Light ◽  
Generative Organs

During long-term axenic culture of Chara continuous illumination (L=24) increases mitotic activity of almost all types of cells. In such conditions only initiation of oogonia is inhibited, leading into a strong predomination of male generative organs. Prolonged darkness (L:D=1:23) exerts a mitodepressing effect. Oogonia and antheridia are especially susceptible to the reduction of the light period. Modifications of the elongating growth in various photoperiods are different in the polyploid regions of the vegetative thallus and in haploid cells of the antheridial filaments. Segments of both axial internodes and lateral pleuridia increase their dimensions at L:D=1:23, whereas at L=24 their growth is significantly inhibited. Different reaction is noted in the cells of antheridial filaments: at L=24 they are about 10% longer than in the control (L:D=14:10). The duration of the antheridium aevelopment, from the stage of unicellular filaments to the moment of antheridium opening, is 1.5 days shorter at L=24 as compared with the control. This shortening includes proportionally both the period of divisions within antheridial filaments and the period of spermatozoid differentiation.

Mechanical and photosynthetic constraints on the evolution of plant shape

Paleobiology ◽  
1984 ◽  
Vol 10 (1) ◽  
pp. 79-101 ◽  
Author(s):  
Karl J. Niklas ◽  
Vincent Kerchner
Keyword(s):  
Photosynthetic Efficiency ◽  
Growth Habit ◽  
Three Dimensional ◽  
Main Axis ◽  
Moment Arm ◽  
Total Moment ◽  
Moment Arms ◽  
Branching Patterns ◽  
Upper Silurian ◽  
Lateral Branches

A computer model is presented which is capable of calculating both the photosynthetic efficiency (I) of any specified plant shape and the stress related to the total moment arm (M) imposed on vertical branching patterns. Computer simulations indicate that a flattened plant thallus and an erect branching growth habit are two plant shapes capable of optimizing photosynthetic efficiency during indeterminate growth. These two morphologies have geometric analogues in the dorsiventral thalli of some bryophytes and in the vertical axes of mosses and tracheophytes, respectively.Extension of the model to complex, three-dimensional branching patterns indicates that I and I/M are maximized when branching is overtopped (treelike, with lateral branches on a main axis) and when lateral branching systems are planated (frondlike). Geometric alterations of branching patterns that result in optimization of I and I/M can be simulated by computer and are shown to be similar to morphologic alterations attending the early evolution of vascular land plants. It is suggested that a number of major evolutionary trends seen in Upper Silurian to Upper Devonian times can be expressed in terms of optimizing the display of photosynthetic tissues (I) or the balance between photosynthetic efficiency and incurred moment arms (I/M).

A silicified semiaquatic dicotyledon from the Eocene Allenby Formation of British Columbia

1973 ◽  
Vol 51 (7) ◽  
pp. 1373-1377 ◽  
Author(s):  
Coleman R. Robison ◽  
Christopher P. Person
Keyword(s):  
British Columbia ◽  
Adventitious Roots ◽  
Single Layer ◽  
Salient Feature ◽  
Anatomical Structure ◽  
Main Axis ◽  
Epidermal Cells ◽  
Coal Basin ◽  
Lateral Branches ◽  
Air Cavities

A silicified dicotyledon rhizome is described from the Eocene Allenby Formation of the Princeton Coal Basin, British Columbia. The primary and secondary vascular tissues of the rhizome form a narrow cylinder around a broad, parenchymatous pith. The rhizome's salient feature is a wide cortex in which there are numerous air cavities. In most specimens the cortex is surrounded by a single layer of epidermal cells but in some there is evidence of periderm initiation. Small lateral branches are borne on the main axis, and both the main and lateral axes bear broad, clasping leaf bases and adventitious roots. The affinities of this rhizome are presently unknown, but its anatomical structure is indicative of a semiaquatic plant.

scholarly journals Callose formation in injured cells of the vegetative and generative thallus of Chara vulgaris L. Absence of callose in the process of cytodifferentiation

2014 ◽  
Vol 57 (1) ◽  
pp. 21-30 ◽  
Author(s):  
Mirosław Godlewski
Keyword(s):  
Water Potential ◽  
Protective Role ◽  
Sudden Increase ◽  
Callose Deposition ◽  
Chara Vulgaris ◽  
Callose Formation ◽  
Extracellular Environment ◽  
Vegetative System ◽  
Generative Organs

In an alga <em>Chara vulgaris</em> L. the processes of differentiation of vegetative system cells of the thallus, and initiation and development of generative organs are not associated with callose formation. It was demonstrated that damage to any of the somatic cells and also generative and nongenerative cells of the antheridium and oogonium are capable of callose formation independently of their developmental stage. The localisation and thickness of these layers depend on the way the cells are injured and on their size. The protective role of callose in such cells may consist, beside strengthening the damaged walls, in protection of the symplast by formation of callose deposits on the walls with plasmodesmata; it may also consist in increasing the water potential of the cells. Experiments in which callose deposition was provoked by pressing of the cells or damage leading to a sudden increase of the water potential of the extracellular environment suggest that a sudden increase of tension in the cells may be a factor triggering the "callose effect".

Xylary union between elongating lateral branches and the main stem in Populus deltoides

1983 ◽  
Vol 61 (4) ◽  
pp. 1040-1051 ◽  
Author(s):  
Philip R. Larson ◽  
David G. Fisher
Keyword(s):  
Populus Deltoides ◽  
Secondary Xylem ◽  
Cambial Activity ◽  
Main Axis ◽  
Main Stem ◽  
Leaf Trace ◽  
Primary Xylem ◽  
Lateral Bud ◽  
Lateral Branches ◽  
Secondary Vessels

The vasculature of elongating lateral branches was examined to determine how vessels produced in the branch unite with those produced in the main stem axis to form a continuous transport system. In a previous study it was found that differentiation of both primary and secondary xylem in a lateral bud or branch is independent of that in the main axis; i.e., xylem does not differentiate into the bud or branch from the main axis. When serial sections of the nodal region are followed downward, the bud vascular cylinder merges with that of the main axis and the adaxially situated bud traces (those nearest the stem) enter the bud gap margin first. The primary vessels of these bud traces differentiate in an oblique downward path along the margins of the bud gap, and they form radial files of primary vessels that lie adjacent to primary xylem of leaf traces in the stem. Traces situated more abaxially in the bud (those farther from the stem) contribute to other radial files of primary vessels, each of which lies progressively closer to the bud gap. Secondary xylem is initiated in the stem before it is in the branch. Consequently, the last-formed metaxylem vessels of the bud traces are continuous with secondary vessels of the stem. These latter vessels lie in the stem secondary xylem immediately external to primary xylem from the bud. Secondary xylem in the branch is initiated when foliage leaves and internodes mature. Secondary vessels formed in the branch traces are continuous with secondary vessels in the stem; these vessels are embedded in a matrix of fibers. Because cambial activity is more vigorous in the stem than in the branch, two vessels that are radially adjacent in the branch may be widely separated by fibers in the stem. The central trace of the axillant leaf enters the gap immediately below the last branch traces; at this level in the stem the leaf trace vasculature is entirely primary. The stem secondary xylem that overlies the leaf trace is continuous with that in the axillary branch.

New occurrences of trimerophytes from the Devonian of eastern Canada

1978 ◽  
Vol 56 (24) ◽  
pp. 3052-3068 ◽  
Author(s):  
Jeffrey B. Doran ◽  
Patricia G. Gensel ◽  
Henry N. Andrews
Keyword(s):  
Middle Devonian ◽  
Early Stage ◽  
Lateral Branch ◽  
Main Axis ◽  
Eastern Canada ◽  
Morphologic Variation ◽  
Lateral Branches ◽  
Branch Type ◽  
Established Species ◽  
New Occurrences

Pertica dalhousii n.sp. is described from the late Lower or early Middle Devonian of New Brunswick. The plant is known from a central axis with spirally arranged, mostly dichotomous lateral branches. Some lateral branches terminate in erect clusters of 32–128 fusiform sporangia. Spores are circular, trilete, with a detachable outer sculptured layer, and resemble the dispersed spore genus Apiculiretusispora Streel. A trimerophyte from Gaspé is described and provisionally designated as cf. Pertica sp.; the specimens are too incompletely preserved to be assigned to any established species, but they add further information about morphologic variation in the genus Pertica.With the addition of new plant types referable to the trimerophytes, distinctions between genera and species are becoming less readily apparent, supporting the suggestion that the trimerophytes are a group of closely related plants in which considerable evolution was occurring in late Lower and Middle Devonian times. Additionally, these plants appear to represent an early stage in the differentiation of a distinct main axis – lateral branch type of organizaiton that probably led to the later evolution of megaphyllous leaves.

scholarly journals Effects of gibberellic acid and AMO-1618 on the development of vegetative systems in generatively matured thalli of Chara vulgaris L.

2014 ◽  
Vol 49 (4) ◽  
pp. 445-458 ◽  
Author(s):  
Maria Kwiatkowska ◽  
Mirosław Godlewski
Keyword(s):  
Gibberellic Acid ◽  
Mitotic Activity ◽  
Main Axis ◽  
Chara Vulgaris ◽  
Cell Divisions ◽  
Lateral Buds ◽  
Apical Cells ◽  
Axenic Conditions ◽  
High Level ◽  
Amo 1618

Effects of GA<sub>3</sub> (10<sup>-11</sup>-10<sup>-4</sup> M) and AMO-1618 (10<sup>-6</sup>-10<sup>-4</sup> M) on the development of generatively matured thalli of <em>Chara vulgaris</em> were investigated during 21-day culture of plants in axenic conditions. It has been found that in the main bud the divisions of apical cells of the thalli are not stimulated by GA<sub>3</sub>, whereas in the lateral buds the cell divisions are stimulated by higher GA<sub>3</sub> concentrations. Subsequent mitotic activity of the apical cells in the branches of the main axis is not stimulated by GA<sub>3</sub>, whereas the lateral buds of these branches are activated. The development of rhizoids in younger nodes is accelerated by high GA<sub>3</sub> concentrations. The elongation of the polynuclear, internodal cells of the main axis and that of pleuridia are inhibited proportionally to the GA<sub>3</sub> concentration. AMO-1618 stimulates the development of new nodes, elongation of internodes and delays the activation of lateral buds as well as the formation of rhizoids. These results suggest that the GA<sub>3</sub>-induced inhibition of elongation of the thalli and diminution of the apical domination is connected with a high level of endogenous gibberellins in the generatively matured thallus.

Structure and development of shoots in Cytisus scoparius

1990 ◽  
Vol 68 (12) ◽  
pp. 2576-2582 ◽  
Author(s):  
Tian Su Zhou ◽  
Noboru Hara
Keyword(s):  
Growing Season ◽  
Lateral Branch ◽  
Main Axis ◽  
Leaf Primordia ◽  
Axillary Meristem ◽  
Cytisus Scoparius ◽  
Lateral Branches ◽  
Winter Buds ◽  
The Relationship ◽  
Characteristic Manner

The vegetative winter bud of Cytisus scoparius Link contains about nine leaf primordia. It grows into a main axis during the current growing season. At the end of the growing season, a shoot system consisting of a main axis and many lateral branches is formed. The lateral branch originates as a primordium when winter buds expand in spring, from the axil between the sixth and eighth leaves (numbered from the base of the bud), following which the succeeding primordia of branches appear sequentially. These lateral primordia continue to extend synchronously with the extension of the main axis during the growing season. By the end of the growing season, the lateral branches have reached various lengths and are arranged in a somewhat characteristic manner on the main axis; the relatively long branches are often located on the portions with ternately compound leaves and are associated with the vigorous elongation of the main axis. The relationship between the growth of the lateral branches and the main axis is discussed. Key words: axillary meristem, Cytisus, proleptic shoot, sylleptic shoot.

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