The transverse orientation of stomata



The transverse orientation of stomata

by Butterfass T. (1987)

Botanisches Institut der Johann Wolfgang Goethe-UniversitätFrankfurt a. M. 11Federal Republic of Germany


in Bot. Rev (1987) 53: 415-441 –


The orientation of cell walls co-determines development. The orientation of the slits of the stomata can be used for analyzing the factors involved.

A comprehensive and annotated list is given of those plant species most of whose stomata are known to be oriented transversely to the long axis of an organ or a main rib. Included are also species showing only a trend toward transverse orientation.

Transverse orientation is known from a few mosses, from Bennettitatae, fromAzolla and some other ferns, and from species of about 45 families of spermatophytes. It could be confirmed that succulent species show the trait more often than do other plants.

Two thirds of the species listed belong to the Caryophyllales and Santalales, a few only to Asteraceae, but none to Rubiaceae, Cyperaceae, Poaceae, or Orchidaceae. Hence, the incidence of succulent species or of species with some succulent traits within the two orders and the lack of such species among other taxa may account in part for the distribution.

On the other hand, many succulent species do not show transverse orientation whereas in, e.g., Casuarina and Tamaricaceae transverse orientation goes together with non-succulent xeromorphy; Azolla shows no xeromorphy at all. Various factors, separately or together, may be involved. Proposed mechanisms determining the orientation of cell walls have been compiled from literature and are discussed.


Counting of Stomata



Counting of Stomata from Different Types of Leaves

by Suthar K., Sutariya K., Yadav P., Menon S. (2017)

Kirti Suthar, Komal Sutariya, Pooja Yadav, Sheeba Menon

Biology Department, K.K Shah Jarodwala Maninagar Science College, Maninagar, Ahmedabad


in International Journal of Trend in Scientific Research and Development (IJTSRD) 1(6): 1068-1075 –


Stomata play a vital role in a plant’s life. It helps in the process of Photosynthesis and Respiration. The exchange of gases also occurs through stomata. Thus Stomata is very important part of the plant.

Few plants belonging to class Dicot and Monocot were collected to study the number of stomata present in their leaves. Leaves from Herbs, Shrubs, Trees and Climbers were collected for the study. These leaves were collected from wide areas from Ahmedabad city. As the stomata are located on the dorsal surface of leaf, the chlorophyll was scrapped from the dorsal surface.

The chlorophyll content should be removed to see the stomata clearly. This chlorophyll content was removed using blade/scalpel and water. The number of stomata was calculated using ‘Micrometer slide’. The scale on ‘Micrometer scale’ was 0.01 micrometer.

This ‘Micrometer slide’ was the microscope and the scale was fixed. After that only the number of stomata was calculated. It was found that ‘Tulsi’ had the maximum number of stomata among the dicotyledons whereas ‘Pancreatium sp’ had the maximum number of stomata among the Monocotyledons.

The stomata were calculated in fresh leaves of collected plants. The number stomata were carried out under ‘Compound Microscope’. The number of stomata is directly related to the enhancement of Physiological process.

Stomata in woody plants



Morphological characteristics of leaves and stems of selected Texas woody plants

by Meyer R. E., Meola S. M. (1978)





in USDA Techn. Bulletin no. 1564, 200 pp. –

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Stomatal types

Diagrammatic representation of different types of stoma in dicotyledons and monocotyledons. Guard cells are hatched. The other are subsidiary cells/epidermal cells.


Top 8 Types of Stoma in the Epidermis | Plants

Prateeksha L. (x)

In addition to the above five types of stoma in dicotyledons Van Cotthem illustrated two more types of stoma, which are as follows (Fig. 12.10):

The following points highlight the top eight types of stoma in the epidermis. The types are: 1. Anomocytic 2. Anisocytic 3. Paracytic 4. Diacytic 5. Actinocytic 6. Gramineous 7. Hemiparacytic 8. Hexacytic.

Stebbins and Khush did not propose any terminology to aid their concepts and distinguished them as First type, Second type, Third type and Fourth type which are as follows (Fig. 12.11):



Five types of guard cells of stomata

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Figure 1. A. Dumbbell type (Cyanodon). R. Rectangular type-A (Cyperus). C. Rectangular type-B (Eriocaulon). D, E. Elliptic type (Scilla i+ Mo//uyo respectively). F. Right-angle type (Azolla). y, Guard cell; p, pore; s, subsidiary cell; t, thick-walled areas; th, thin-walled areas.


The taxonomic value of guard cells seen in surface view

by Rajagopal T., Ramayya N. (1977)

T. KAJAGOPAL, Department of Botany, Arts and Science College, Warangal-l, A. P., India

N. RAMAYYA, Plant Anatomy and Taxonomy Laboratory, Department oj Botany, Osmania University, Hyderabad, India


in Botanical Journal of the Linnean Society 74: 57-61 –


Guard cells, as seen in surface view, are classified into five types; dumb-bell type, rectangular type-A, rectangular type-B, elliptic type and right-angle type.

It is proposed that this more detailed classification may have value at higher taxonomic levels, particularly within the Monocotyledones.

The pattern of cellulose crystallinity in stomata of floating plants was altered as a consequence of similar evolutionary pressures

Floating aquatic plants have stomata with an altered pattern of cellulose crystallinity. Crystallinity patterns in the land plant Cyclamen persicum (A,B); and aquatic plant Nuphar lutea (D,E) shown by liquid crystal polarized light microscopy (LC-PolScope). A schematic representation of the regular crystallinity pattern in angiosperm kidney-shaped stomata (C) and the altered pattern in the stomata of floating plants (F). The retardance colour scale bar codes the retardance range. Scale: 25 µm.


Permanently open stomata of aquatic angiosperms display modified cellulose crystallinity patterns

by Shtein I., Popper Z. A., Harpaz-Saad S. (2017)

Ilana Shtein, Zoë A. Popper, Smadar Harpaz-Saad,

Department of Mechanical Engineering, Ben-Gurion University of the Negev, Beer Sheva, Israel,


in Plant Signaling & Behavior 12(7):  – – Article: e1339858 –


Most floating aquatic plants have stomata on their upper leaf surfaces, and usually their stomata are permanently open.

We previously identified 3 distinct crystallinity patterns in stomatal cell walls, with angiosperm kidney-shaped stomata having the highest crystallinity in the polar end walls as well as the adjacent polar regions of the guard cells.

A numerical bio-mechanical model suggested that the high crystallinity areas are localized to regions where the highest stress is imposed. Here, stomatal cell wall crystallinity was examined in 4 floating plants from 2 different taxa: basal angiosperms from the ANITA grade and monocots.

It appears that the non-functional stomata of floating plants display reduced crystallinity in the polar regions as compared with high crystallinity of the ventral (inner) walls. Thus their guard cells are both less flexible and less stress resistant.

Our findings suggest that the pattern of cellulose crystallinity in stomata of floating plants from different families was altered as a consequence of similar evolutionary pressures.

Do corollas have stomata?



Do corollas have stomata?

Teixido A. J. (2017)

Alberto L. Teixido, Federal University of Minas Gerais, Brasil

Evidence suggests that petals have none (Patiño and Grace 2002) or only few stomata and that water loss regulation is very limited and largely depends on their cuticle physics (Nobel 2009). Does anybody know if there is any particular study about this? How do corollas regulate water loss?
Nobel, P.S., 2009. Physicochemical and Environmental Plant Physiology. Elsevier Academic Press, Toronto.
Patiño, S., Grace, J., 2002. The cooling of convolvucaceous flowers in a tropical environment. Plant Cell Environ. 25, 41–51.