Larry Dighera wrote:

Anyway, cytokines work differently in different tissues,



That's an interesting bit of information. Are you able to describe
any of the differences?



No, not formally. My last plant physiology class was 15 years
ago... My books are at least that old, and may be out of date.


That may work for the potted plant trade,



How do they use it?



Well, for example, if you want to sell mums or whatever in full
bloom, it wouldn't hurt to tinker with mother nature a bit to get more
blooms (or longer stems, see below). Here are a few concrete examples
(not all pot plants):

Gibberellic acid increases fruit set in blueberry
http://www.ipm.msu.edu/CAT01_fruit/F05-15-01.htm#6
Increasing stem length in pompom mums
http://www.actahort.org/books/167/167_11.htm
Gibberellins help prevent leaf yellowing in mums
http://www.endowment.org/projects/2002/reid02.htm
Improves germination of some seeds
http://www.actahort.org/books/73/73_18.htm

That will get you started... But obviously the effect on the seed
is different than the effect on the flower (blueberry), or stem (mum).


but I'd wager that you are more interested in keeping a specimen around
for a while.



Control of plant growth and enhancement of size could be useful tools,
but I suspect that "deficit spending" of plant resources may affect
future plant performance. However, if the GA-3 induced increase in
growth rate can be sustained with increased light, water, and
nutrients ...



Of course if you can keep a plant at optimum light, water, and
nutrient level, you are better than I... I suspect merely (_merely_!)
doing this would be a substantial improvement, regardless of GA
application. If you can get an improvement over this baseline, then it
is well worth it, however. It is a commercially viable process for a
number of crops, I can't imagine mum growers spending money to spray
with GA if it didn't improve their bottom line.


Rob

--
Rob's Rules: http://www.msu.edu/~halgren
1) There is always room for one more orchid
2) There is always room for two more orchids
2a. See rule 1
3) Always have at least three rules