Re: Giberillic Acid

>Steve Pushak - spush at hcsd_hac.com - Vancouver, BC, Canada said:
> The TAG  Vol 8 No. 5 (Sep-Oct 95) issue contains an interesting
> article on the use of Gibberellic acid, GA3 "plant growth regulator".
> Is this a kind of hormone for plants? 


> ...mentioned the use of GA3 or in conjunction 
> with plant growth regulator benzyladenine to break the dormancy phase
> of Aponogetons. It is said that Gibberellic acid is available in many
> garden supply stores.

> This sounds very promising for use with Aponogeton madagascariensis!! :-)
> Comments??

I'm playing hookie from a meeting, so I'll make this short.
If anybody cares, I'll dig up more from my books.

There are only a few hormones that regulate plant physiology.
This is very fascinating (to me), because for most animals
we have hormones for everything.  Plants on the other hand
rely upon the relative concentrations of only a few hormones
to regulate all their morphology and biology.

I'm remembering back eight years, so here goes:

IAA - Indol Auxillic Acid is a plant hormone produced at the
      terminal meristem at plants, inhibits lateral shoots.
      That's why cropping the top of your apple tree gives
      you a bushier tree.  Also, the hormone breaks down
      farther down into the plant, which is why Bacopa
      sends out lateral shoots at the base when it gets tall
      enough (the terminal meristem is far enough away).  Also,
      cropping the top of your anacharis allows TWO shoots to
      form at the fork, because IAA is temporarily absent.
      The taller one will produce more IAA and suppress the
      shorter, until they both get tall enough to not impact
      each other.  This is a (very) important hormone that I 
      think of regularly in my pruning. 

CAA - Trying to remember

GA - Giberillic Acid, I think is a growth inhibitor.  It is
      sprayed on potatos harvested in the Fall to keep them
      from spouting over the winter.

AA - Abscisic Acid, concentrations higher in Fall forces tree
     to cut nutrients to leaves (abscise) and fall.

Again, proportions of all of these to each other is what's
important for plants.