Re: REB: fall cycle vs other

 Artic Fox is a oncer. Occasional and rare reports of rebloom will not change
that.

What Richard did to determine if bud set had occurred, is cut he leaves off
until he had a clear look at
apical meristem. This is standard proceedure in this type of study. If anyone
has the reproducton of the early AIS bulletins, check Jan 1923. That is
correct, January nineteen twenty three. Issue #7, part 2. Article by Marion
Shull pg 17-19. A good explination of this proceedure, and good drawings of an
initial flower bud.  I have scanned these and could post to Iris photos if
people wish to look at it and don't have their own copy

Oncers and fall cyclic cultivars  need the further flower initiation
trigger(s) to develop flower stalk.
Direct rebloomers (summer rebloomers)  develop flower stalk as soon as flower
bud is set. No rest, no delay. And it does not mattter what temperature is
after the bloom initiation. It is an on switch, and a go.

Whenever Rebloomers don't need the same flower bud tigger. That is they don't
need the 6 days of temperature between 16 and 21 C  to have bud set, They set
flower buds as soon as fan is mature.

As long as proper conditions occur, for summer rebloomers, that is each fan as
it  reaches maturity and it  gets the temperature conditions, it  will produce
a flower stalk.  If min temperature isn't reached, ie too hot or too cold,
then the new mature fans will not set flower bud and will not bloom. Thus in
climates where they get these temperatures through summer the direct bloomers
will continue. Each fan being induced as it reaches maturity and has
temperature trigger.   But, and the big but, is that they won't bloom until
they have the key temperature.  Thus the delay to start rebolom. And if  min
temeratures  is not in target range, rebloom stops. thus in warm climates. An
early rebloom , and then nothing for  awhile, until temperature trigger
occurs.

Whenever rebloomers, don't need these temperature conditions. And can start
rebloom a week after they have finished spring bloom. And will put up further
rebloom, regardless of having or not having triggering temperature range. They
don't need this trigger temperature.

Last year, I followed Immortality and Queen Dorothy through season ,after
spring bloom. we had a warm summer, so good growth.  I took repeated photos of
fans of each. The mature fans just sat there, doing nothing, for about 4-5
weeks. As soon as I got triggering temperatures, they proceeded to develop
flower stalks and increases started to grow. the photo documentation is in
Spring Rebloomer article.  Thus bloom in mid August. The whenever rebloomers
had been blooming since end of June, when TBs were just finishing blooming.

Crosses of Immortality and Forever Blue produced a lot of ugly oncers. As did
all sorts of other crosses of FB with  Summer Rebloomers. Thus differerent
genetics. Thus the search for and explination of what is going on.

A plant that has direct blooming genes and fall cyclic rebloom  genes will
perform as a direct bloomer.

A plant with whenever  genes and summer  genes will perform as a whenever
rebloomer. etc, etc. What  genes are there that trigger bloom first will do
so. the other genes are then irrelevant, and may as not as well be there ( A
deduction, not experimental data)

Betty, Did you get summer rebloomers from crosses of summer rebloomers with
sporatic rebloomers?

Chuck Chapman

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