RE: Hyb Daylight Independent Correction

The study I was mentioning is
"The genetic architecture of reproductive isolation in Louisiana irises: flowering phenology".
Martin NH, Bouck AC, Arnold ML.Genetics. 2007 Apr;175(4):1803-12. Epub 2007 Jan 21
It can be found online at http://www.genetics.org/cgi/content/full/175/4/1803
The species involved are I.fulva and I.brevicaulis.That's what happens when you write late at night.
They have some nice graphs of the blooming histagrams, of how many bloomed at what times, in two locations, one wet one dry.
They also anlalysed factors involved in determining bloom time. It was done following an analysis of the genetic code. they found 16 factors, four were acountable for most of the variations. Ther were four factors working against the others. If it was just one gene, then it would have sorted out into two distint groupings in the back cross of F1 to parents.
Thus we have a multifactor model of bloom time controlers. This is only on the one of the contolling factors, the timing of the bloom.
As palnts differentiate into species. as iris has done, there is over time some changes in the many bio-chemical pathways. The crossing of species results in some interesting miscommunications. Particularly as over time you can get in one plant the receptor genes from one species and the signal genes from another. The biological signal may have some differnce, such as replacement of a -OH molecule with a rhamose sugar molecule ( as happens with anthocyanins) and receptor just can't use the signal. There are also several variations of the vernalization gene that have been identified (no information available for iris) in several plants. Thus signal to prevent blooming in some circumstance just does not work, and plant blooms at a time it norml wouldn't.
If you check write up on Rebloomers in World of Iris you will find a long list of iris species for which rebloom has been reported at some time or other. I had a cultivar of I. variegata here that rebloomed quite regularly as a fall cyclic rebloomer.
So, bottom line, I don't think that we can point to any particular species as contributing rebloom. I suspect that it is more an effect of interspecies mix of bloom signals, the ones initiating and the ones inhibiting bloom. 

Chuck Chapman

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