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  GA3 in seed germination
From: Iza & Carol Goroff goroff at idcnet.com> on 2001.05.24 at 22:25:06(6553)
A typical dose for seeds is from 250 to 1000 parts/million. 1 gram should last much, much longer. The use of GA3 was thoroughly investigated by Dr. Norman Deno in his Seed Germination and Practice (and in two subsequent supplements), where he investigated various
approaches for germinating over 5,000 species of plants. GA3 does not easily dissolve in water. I cannot find my copy of Seed Germination and Practice to give the the procedure for its dilution, although in the supplements he has no problem germinating the aroids listed
without the use of GA3, instead using different temperature/time patterns.

My suggestion is to NOT put all of your eggs (seeds) in one basket. While GA3 works wonders with some species, others are killed.

Iza Goroff

From: "Nyles" metopium at hotmail.com> on 2001.05.25 at 03:30:14(6562)

I always make a potassium salt of GA.
It's been shown to be more active than other salts, or even pure GA.
GA is not freely soluble in water, so the easiest way to do this whole
procedure in your living room is to measure out the amount of distilled
water into any glass container under a good light.

Add the amount of GA that you want.

You'll see the powder floating on top of the water.
(A good conversion from parts per million (ppm)to something you can deal
with is to change it to milligrams per liter...not exact but VERY close)

Slowly add potassium hydroxide (KOH) to the mixture while stirring gently.
Use very small amounts at a time.

At some point the powder will suddenly disappear and go into solution.

The Ph should be OK if you haven't overused the potassium hydroxide.
If your worried, use litmus paper or a pool Ph test kit.

Hope that this helps!


From: mburack at mindspring.com on 2001.05.25 at 15:02:49(6566)
Dear Nyles,

Many thanks for the info....but as far as pH goes... what number should I be looking for? "7" or is there an acceptable deviation higher or lower?


From: Ted.Held at hstna.com on 2001.05.26 at 06:06:44(6569)
GA is supposed to be freely soluble in ethanol (Merck Index). So you could
dissolve your appropriate amount in alcohol (try gin or vodka) and add that
to your water. That will save you messing around with potassium hydroxide
and pH.

From: magrysbo at shu.edu on 2001.05.26 at 06:07:11(6571)
Can you dissolve in a little bit of alcohol and then dilute with water?

From: "Nyles" metopium at hotmail.com> on 2001.05.26 at 15:10:34(6578)
My only hesitation with dissolving GA in ethanol and then mixing in water
would be the GA precipitating out of solution. Since your using so little
you may not see it, in which case you might as well just use water.
Needless to say, if you use alcohol of any kind, use very little.

Any chemists out there?

Regarding Ph, you're always safe around 7 give or take.
We have very basic water here in Tucson and all my plants do well...
..except that one protea.


From: Ted.Held at hstna.com on 2001.05.29 at 13:23:31(6596)
The GA will precipitate out if you put in more than is soluble. The idea is
to target your one gram per liter, dissolve that in alcohol, and dilute
with water to make a liter. If GA is soluble at 1 gram per liter, it will
not precipitate at this level, alcohol or no alcohol. Merck reports GA as
"slightly soluble". This is not specific. But if literature suggests using
it at 1 gram per liter, it probably means that GA is soluble to this
extent. Using the alcohol route just speeds the dissolution process and
avoids the possible problem of some of your GA ending up on the container
sides, insoluble and not noticed, wasted. Potassium hydroxide (or sodium
hydroxide, or any number of other bases) will help things along. The
problem with these is achieving a nice, neutral pH. Hardly impossible, but
a pain for the basement or backyard gardener.

I am a chemist, though not a specialist in GA. But what I write is pretty
elementary chemistry.

From: "Nyles" metopium at hotmail.com> on 2001.05.29 at 20:57:54(6598)
Not to beat a dead horse.

In my personal experience, I've never gotten GA to disolve in any amount of
water, certainly not at 1gm/liter.
I'm not saying it can't be done, just that I haven't been able to do it.


From: magrysbo at shu.edu on 2001.05.30 at 02:00:28(6603)
Biochemist/Molecular Biologist.

"Nyles" @mobot.org on 05/26/2001 11:10:51 AM

Please respond to aroid-l@mobot.org

Sent by: aroid-l@mobot.org

From: "Ron Iles" roniles at eircom.net> on 2001.05.30 at 13:33:39(6610)
Some of the cultivars of Spathiphyllum we get in Ireland from Holland are
flowering as though there was no tomorrow, and there can be as many as
twenty inflorescences on one small clump plant (like Chopin) maybe due to GA
or something even more potent, the spathes even look tortured, and some of
the leaves are white streaked! I recommend giving plants just what they
need and oppose all green witchcraft which causes floral madness. And
maybe the potions could turn biological predators into vegatarians. It's
not nat'ral. Nope!

From: Ron McHatton rmchatton at photocircuits.com> on 2001.05.30 at 14:35:47(6613)
Not to continue beating the dead horse, but I can't stand this anymore. GA
is slightly soluble in water and should dissolve on its own to levels which
will be effective. The problem is the rate at which it dissolves, and the
fact that the powdered free acid is hydrophobic which makes wetting of the
salt difficult. The free acid is soluble in methanol, ethanol, acetone and
aqueous solutions of sodium bicarbonate. If you go the route of dissolving
first in alcohol, you should dissolve the GA in a very small amount of the
alcohol (if you use drinkable stuff, you need the proof as high as possible
or its just trying to dissolve GA in more water), then dilute to final
working strength. At concentrations in the ppm range, the GA will not
reprecipitate when water is added. That trick is used with alot of
sparingly to slightly water soluble organics. You can't get them to
dissolve, but once you do dilute solutions are pretty stable.

GA is also soluble in water solutions of sodium bicarbonate. I believe
this or sodium acetate is the medium that formed the basis of the water
miscible material someone else wrote about. Anyway, sodium bicarbonate is
easier to get than potassium hydroxide and no where near as corrosive. The
pH of a 7 gram per liter solution of sodium bicarbonate is about 8.4. You
can double that concentration and not move the pH very much. Its a
little high, but not so high that any plants would be damaged and you don't
get into the vicious cycle of pH up and down trying to control KOH.
Solubility as well as the rate at which the material dissolves is
dependent on temperature and the bicarbonate solution. You shouldn't have
a problem with a final bicarb concentration around 7 g/l. I would prepare
a small amount of sodium bicarbonate solution that is on the order of ten
times that concentration, warm it slightly and dissolve the GA in that
concentrated solution. Dilute the concentrate by a factor of 10 and apply.

Ron McHatton

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