Plant Hormone Production

We don’t talk much about plant hormones, or at least we haven’t in a while. There are six (by some counts): auxin (IAA), gibberellin (GA), cytokinin, abscisic acid (ABA), ethylene, and brassinosteroid (Br). I haven’t read up on the Br but of the remaining five I’d like to talk about IAA, GA, and cytokinin.

Specifically, is there a way to introduce more of GA or cytokinin, or is there a way to induce more production of GA or cytokinin?

There is some school of thought about how the ratio of these three hormones, IAA, GA, cytokinin, (and even the others), will induce predictable results through measured application. I’m curious how the average farmer, if she so chose to do so, would know how to regulate the application of, or the introduction of materials promoting IAA, GA, and cytokinin such that abnormal results would not occur.

So, how can we promote production of GA and cytokinin and can we do so in a regulated manner? I’m comfortable with my current understanding of auxin, the role it plays, and how to manage it in an indoor garden. GA and cytokinin, I’m not sure about. But we all need to know.

 

Nice links and both show the benefit of using PGR's selectively. And they also indicate a lot is to be learned about PGR's in general. From what little I've researched thus far the control of hormones, specifically GA and cytokinin, are predominanty genetically controlled and managed. Am I understanding that correctly? If so it seems the only 'simple' way to override that is through the use of one of the synthetic PGR's.

Has there been research on how to invoke, or provoke perhaps, an environmental stressor or variable that is known to cause a plant to produce one or the other of GA and cytokinin. I do believe I recall a dialog long ago in the past about certain organic ammendments we add to our mixes that are thought to promote cytokinin response but I'm fergetting ATM . STM loss being what it is and all.

I've noticed various grades of GA are available for purchase but personally at this point I'd be leary of using it because I don't understand it completely or how its ratio to other hormones can cause a negative consequence. Frequency, dillution rate and all of that. I am interested in any environmental variables that I could tweak to encourage production of one or the other. Such as, it is thought that intense blue light spectrum is thought to stimulate cytokinin production. Or, if there are materials I could add that would foster plant production of either hormone.

And then I guess one has to decide, "Is this a safe practice to employ on a consumable product?" if we use a labeled, manufactured product.

Seems like a good discussion point.

 

Sure haggard here ya go. My connection is pretty slow so I'm gonna include only a couple as I have a difficult time downloading large files.

These are basic introductions to the different plant hormones. Note that only recently was brassinosteroid given to a sixth class where previously there were only five classes of plant hormones. IDK when the sixth class was added.

Plant growth and hormones, -Master Gardener Training, Oregon State University

Plant Hormones

Now that you know each hormone you can enter a search string for each one and receive 10's of thousands of hits. Limit your search to .edu sites for the latest and most meaningful research.

As comfrey has pointed out Plant Growth Regulators, or PGR's, are employed on a massive scale both in agriculture but most notably in horticulture. The latter group using perhaps the most of the many different types of PGR's in order to benefit their industry and their crops - ornamental and flowering plants!

Whereas my OP was to understand if we could incite or otherwise encourage hormone production versus that of applying a topical spray or soil drench, we can also see that there are products that allow for this. I'm not hawking or pimping any particular product, rather I want to try and work with what naturally occurs albeit on a larger scale that what a normal plant might produce. Scientists and academics continue to discover new hormones within the classes of the currently known hormones so research continues, ala number "six", brassinosteroids.

ABA and ethylene are both important hormones and I think it does us indoor growers to know about and understand both of these as well. In particular those folks that choose to place rotting fruit in their gardens in order to "produce CO2". While CO2 is certainly produced so is ethylene gas. Read up about what ethylene gas does to fruiting plants and one might decide placing rotting fruit in their indoor garden is probably not a good idea when attempting to flower their 10lb indoor monster.

ABA is an interesting hormone and is also a very important part of understanding plant physiology. Absiscion is what causes leaves to drop off and a whole bunch of other stuff with seed and plant roots. And then it gets a bit more complicated when applying and using third-party hormone products containing one of either of the three main hormones auxin, GBA, and IAA. Crop disaster or a side show in the phreak section of the traveling carnival might result - The Tomato that Grew a Beard or sumpin.

Anyway, what we want - all of us - is to create an environment whereby the plant prodcues what it needs in the form it needs it. I'm just trying to figure out if we can trigger/manipulate/force/icite/provoke or otherwise encourage the plant to produce more of a particular hormone. We manipulate plant created auxin when we pinch off or tie off the meristem growing tip forcing auxin back into the lateral branches. When we pinch off the top the auxin is forced downward and the race is on for the lateral branches to produce a new, single, dominant growing tip. Right now, for example, I have in excess of 25 'dominant growing tips' just by canopy management. I want to know how to manipulate the IAA and GBA hormones in a similar yet appropriate manner.

Good stuff if you can get your head around it. Some dewwde posted a thread about "where do you learn what you know (sic)". This is where we can start. As unseeming as it may appear, plant hormones are the basics of plant physiology and we, the indoor growers, simply must know what they are, what actions they cause to occur in a plant, what can we do as tenders to help manage that. That's IMO anyway.

 

Very nice link. Select a chapter, enter a search string. Better, read all the chapters

CQ maybe "you" weren't around here a couple years back, IDK, but I recall a thread where there was some spirited discussion around cytokinin specifically and amendments the gardner could use that helped to promote cytokinin development. Am I confused... again? I'm not thinking chitin. I'm thinking cytokinin. Maybe I just ain't tinking

 

CQ

I've read a little bit about synthesized GA and enough reading to understand that use of GA should be in the hands of trained applicators IMO. One student study I read hypothesized that GA application could be passed on as a heridtery trait in seeds created by application of GA to the buds of flowering plants. Subsequent generations of plants grown from those seeds were observably different in pheno characteristics than generations of their control. I'm not suggesting that is emperical evidence but it was interesting and definitely GA has a role in commercial horticulture. But let me try to restate my original whimsical thought another way.

Another hormone, jasmonic acid, is thought to be the hormone triggered when a plant suffers a wound (it took me a long time to find that one and I found it quite by mistake I might add). So, for example, if for whatever reason we wanted to do so, we could induce the plant to produce the hormone jasomnic acid by simply severing a leaf stem. It's an action we can physically take to force the plant respond with a hormonal response to heal the wound. This would perhaps be considered a genetically encoded response of the plant to deal with that situation.

In that spirit - inciting a response - is there a known way to incite a plant to over-produce GA? I don't want to put a GA product on my produce or my smokeable, I'm just curious if the science guys ever figgured out a way "to poke that dog with a stick" and make it produce GA in extrodinary (above normal) amounts.

 

Howdy chunk. I tell you what. I was poking around in the local GoodWill looking for jars with lids one day back and picked up a 5th edition World of Biology text for $1. LOL. It's an interesting textbook and reference. Very well written and weighs at least 8lbs.

Good deals to be had if we think outta the box sometimes .