How the stomata works and how it can help us.

Discussion in 'Basic Growing' started by daihashi, Mar 10, 2008.

  1. daihashi

    daihashi Registered+

    The stomata are pores on the underside of leaves. These pores are made be cells called Guard Cells or "parenchyma cells" which are used to regulate the size of the opening of the stomata.

    The stomata is used to collect carbon and dioxide and other beneficial nutrients and gases that aid the plant in growth. The stomata is also used in transpiration of water from the plant into the atmosphere.

    In order for plants to take up CO2 for photosynthesis, they must expose the moist surfaces of their leaf mesophyll cells to the air. In doing so, water is lost by evaporation. The evaporation of water from leaves is called transpiration. Under some circumstances, transpiration of water from leaves may act to cool them and prevent damage from high ambient temperature. In general, however, transpiration is neutral or bad for plants. It is an unavoidable loss of water as the plant photosynthesizes.

    To minimize transpiration, movement of gases into or out of a leaf is controlled by the stomata. The stomata are small pores in the leaf epidermis that can be opened or closed. Stomatal opening is highly regulated by multiple mechanisms so as to minimize transpiration. Transpiration is minimized even under conditions of high ambient temperature. (Stomata close at high temperature. They do not open in order to cool the leaf).

    Stomata are composed of two guard cells. These cells have walls that are thicker on the inner side than on the outer side. This unequal thickening of the paired guard cells causes the stomata to open when they take up water and close when they lose water. The opening and closing of stomata is governed by increases or decreases of solutes in the guard cells, which cause them to take up or lose water, respectively.

    In general, stomata open by day and close at night. During the day, photosynthesis requires that the leaf mesophyll be exposed to the air to get CO2. At night, the stomata close to avoid losing water when photosynthesis is not occurring.

    During the day, stomata close if the leaves experience a lack of water, such as during a drought.

    The opening or closing of stomata occur in response to signals from the external environment.

    Light = Stomata open

    Dark = Stomata close

    High CO2 inside leaf = stomata close

    Low CO2 inside leaf = stomata open

    Drought stress = stomata close

    Closure of stomata by drought is caused by abscisic acid, a plant hormone that is synthesized in response to drought. Abscisic acid overrides other signals and closes stomata when saving water is more important than photosynthesis.

    Light causes stomates to open. The minimum light level for opening of stomates in most plants is 1/1000 to 1/30 of full sunlight, just enough to cause some net photosynthesis. Blue light (430-460nm) is nearly 10 times as effective as red light (630-680nm). The wavelengths that are effective in the red part of the spectrum are the same as those that are effective in photosynthesis ie is absorbed by chlorophyll. However, the blue light effect is quite independent of photosynthesis. Photosynthesis will change intercellular CO2 concentrations and may have its effect through number.

    Potassium also plays a large role in the Guard Cells function in opening the stomata.

    Blue-light wavelengths of daylight, detected by zeaxanthin (a carotenoid) activate proton pumps in the guard cell membranes, which proceed to extrude protons from the cytoplasm of the cell; this creates a "proton motive force" (an electrochemical gradient across the membrane) which opens voltage operated channels in the membrane, allowing positive K ions to flow passively into the cell, from the surrounding tissues. Chloride ions also enter the cell, with their movement coupled to the re-entry of some of the extruded protons (Cl/H symport) to act as a counter-ions to the potassium. Water passively follows these ions into the guard cells, and as their tugidity increases so the stomatal pore opens, in the morning. As the day progresses the osmotic role of potassium is supplanted by that of sucrose, which can be generated by several means, including starch hydrolysis and photosynthesis. At the end of the day (by which time the potassium accumulation has dissipated) it seems it is the fall in he concentration of sucrose that initiates the loss of water and reduced turgor pressure, which causes closure of the stomatal pore.

    ABA also seems to trigger a loss of K ions from guard cells. Some workers suggest that in some species, ABA alters turgor pressure without changing solute potential or water potential.

    Potassium is the "plant-preferred" ion for maintaining the water content and hence the turgor (rigidity) of each cell, a biophysical role. A large concentration of potassium in the cell sap (i.e. the liquid inside the cell) creates conditions that cause water to move into the cell (osmosis) through the porous cell wall (Box1).

    Turgid cells maintain the leaf’s vigour so that photosynthesis proceeds efficiently.

    The plant controls the opening /closing of the stomata by regulating the concentration of potassium in the guard cells. A large concentration of potassium ensures turgid cells and open stomata. When the potassium in the guard cells is lowered, they become limp and the stomata close.
  2. daihashi

    daihashi Registered+

    These are excerpts from several articles I read. Or parts of articles that have been put into my own writing.

    Another research article stated the following:

    changes in stomatal aperture caused by decreasing or increasing humidity were followed only after a delay by changes in the potassium content of the guard cells. By comparison, if stomatal movements occurred in response to changes in illumination the relative potassium content of the guard cells correlated continuously with the changes in stomatal aperture. Since the potassium content of the guard cells changed only after most of the stomatal movements in response to changes in humidity were completed changes in potassium content and humidity responses of stomata can be described as following a hysteresis curve.

    With that said I am curious if we can manipulate stomata opening and closing by spraying a very fine mist (almost atomized) of PH'd water with a very small amount of potassium.

    This would increase humidity, add rigidty (through potassium uptake)to the Guard cells which would in turn keep the stomata open longer. This would of course also increase the transpiration rate but as long as you stay on top of watering I think everything should be fine.

    It was also interesting to read that the stomata opens much better under blue wavelength light than it does under red.

    I know there are products such as liquid light that do something similar but I was curious as to how/why it worked and if there is something similar we can do on our own much cheaper.

    I decided to start researching the stomata.

    I'll continue to update this thread as I come across more information.

    Sorry if this was widely known information; just thought I could contribute something to those who were not aware.
  3. CashandPrizes

    CashandPrizes Registered+

    useful info. thanks for takin the time to post it. :thumbsup:
  4. turtle420

    turtle420 Banned

    Long time has passed since cool new info came along!

    Will read this now and let you know my feedback!
    Thanks for this! :)
  5. turtle420

    turtle420 Banned

    Wow... very, very good information in there!!!

    I have a whole bunch of questions for you... but I am running out the door.

    Your idea of opening the stomata with water + K, sounds interesting.

    As I read your article, it kept ringing in my head the NutraMist.
    Have you seen those?

    Their water "mist" is produced by ultrasonics, so the droplette size is reduced to constitute "dry fog" (as opposed to "wet". Wet would be if you put your hand to the mist and it gets wet. Dry, inverse.)

    That little machine might help you with your idea.

    The other thing I thought about was the "SonicBloom" products.
    It is a classical music CD, that has various high-frequency wave forms, and noises from "happy healthy insects". Birds, insects, crickets. Cool stuff!
    It "stimulates" the plants to open up their stomata, thus helping the transpiration. :)

    Anyway, will re-read, and post up them questions!



    -turtle420 :cool:
    Last edited: Mar 11, 2008
  6. daihashi

    daihashi Registered+

    I looked into the nutramist and it looks ideal the problem is with the price tag. $400 is a bit much. I'm going to see if I can find something similar.

    I don't think that wet would be horrible so long as the particles were fine enough.

    I'd like to get a microscope or something to monitor the stomata and possible measure it with and without a very weak potassium water mixture.

    This will probably take a while but I'm sure we can benefit somehow by manipulation of the stomata.

    Let me know your questions. I'd really like alot of feedback/input. We manipulate the plant by ways of training, light, and feeding to recreate a naturally occuring enviorment.

    I don't see why we can't train plants on a micro level as well to get even greater benefits out of it.

    If nothing else I'll learn alot. :thumbsup:
    Last edited: Mar 11, 2008
  7. stinkyattic

    stinkyattic CultiModerVatorAtor

    Good thread; would you mind posting up links to your references? I might make this a FAQ item.
  8. daihashi

    daihashi Registered+

    Sure, I'll post them up as soon as I get home.

    Does anyone know of a very fine mister/spray bottle that doesn't cost an arm and a leg (sub $50.. preferably sub $20).
  9. stinkyattic

    stinkyattic CultiModerVatorAtor

    For the finest spray from the cheapest bottle, I'd look into a surprising source... the girly-products aisle of the supermarket!!!

    The finest re-fillable mister I've found comes on a product made by Neutrogena to treat dandruff overnight- it's their salycilic acid anti-inflammatory spray ("Neutrogena T-Gel Overnight Dandruff Treatment") and has a weird-lookin' nozzle on it that supposedly gives a VERY fine mist for a non-aerosol product. Hang on let me see if I can find a pic of the shit. There. Lots of specialty hair products come with very high-quality, low-droplet-size misters. I'm not saying they are as good as an ultrasonic mister but certainly better than a regular spray bottle for small applications.

    Attached Files:

    Last edited: Mar 11, 2008
  10. daihashi

    daihashi Registered+

    Come to think about it i remember growing up a hair spray that came out with a pump instead of aerosol. It also had a decently fine mist.

    I take it you've used this neutrogena bottle before?

    I bet something like this would work equally as well since this is going to be a foliar application. I could setup a bottle with a fan/cap/hose at the top to be able to mist the plants.

    Cheaper Mister

    crap I don't remember if we aren't allowed to link or if that is just for seed banks and stuff. This place is a science supply store. If it's not supposed to be there I apologize and a mod can remove it.
    Last edited: Mar 11, 2008
  11. stinkyattic

    stinkyattic CultiModerVatorAtor

    Generally I enforce the no-hot linking rule in cases where our vendors' industries and the linked sites' industries are too closely matched. In the grow area, where equipment is concerned, sometimes ya gotta do what ya gotta do, lol! Until I hear otherwise from da bossmans, anyway ;)

    I've used the neutrogena bottle before, just not on plants yet, lol! The dry winter air around here makes my skin angry... I'll let ya know how it is as a foliar applicator as soon as I use one up, hahaha! But I DO use hair-shine product bottles for feeding my Micro foliar and for giving AVID (systemic pesticide).
  12. daihashi

    daihashi Registered+

  13. stinkyattic

    stinkyattic CultiModerVatorAtor

    Very cool, and you have created a FAQ-worthy thread fo sho!
  14. CashandPrizes

    CashandPrizes Registered+

    I looked up the nutrimist ultrasonic fogger. I need to learn more but there might be a way to make your own.

    The only problem that came to mind was, even though its a "dry fog" it still might not be good for your grow lights?
  15. daihashi

    daihashi Registered+

    raise the lights when you apply. Shouldn't be an issue if you use LST.

    I suspect that really this would only be useful as a mid day application. The water + potassium that is. After the plant has lost some turgidity in it's guard cells.
  16. daihashi

    daihashi Registered+

    Thanks. I just wish I had the space to start a new crop. I'll probably start expiermenting on a set of plants during my next grow.

    2 plants for variables and 2 plants grown as I would normally do it. For a constant.

    I have a 400x-900x microscope on order. I think I should be able to see the stomata at 400x magnification.

    edit: Actually I have some herbs and small fruiting plants I could probably test this on. I just need them to grow a little bit larger so I can manipulate the leaves and stuff for the microscope.
    Last edited: Mar 11, 2008
  17. fiddyonefiddy

    fiddyonefiddy Registered+

    im trying the same thing, with the stomatas but opening them even the morning this gets played the bird chirps open the stomata bigger YouTube - The Rainforest just using sound waves, not heavy metal, but thunder b4 watering rain storm while watering YouTube - Sounds of nature - Thunder and rain and draining, just stuff on you tube easily gonna try all of this in my first round of flower. this particular piece was very interesting. kinda on the same page as me just going a different way. also im reading how certain sound waves can trigger celluar growth in the plants.
    Earthpulse Press
    this is also a good read .
  18. daihashi

    daihashi Registered+

    Interesting. I'll be reading up on that as well.
  19. fiddyonefiddy

    fiddyonefiddy Registered+

    yours was a good read too.
  20. SnSstealth

    SnSstealth Registered+

    I have dabbled into stomata research myself, mostly with sound and light triggers.

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