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RE: HYB: Tet x Diploid

Reading the history of the development of colorful, hardy modern tetraploids
makes the process of diploid X tetraploid sound easy.  It isn't!

I had the idea of going after small irises by using diploid species
materials then crossing them with *I. aphylla."  In several years I made
hundreds of pollenizations and never got a single pod.

Among the species, and I no longer remember which were the parents, I had
two diploid hybrids from a number of attempted crosses.  One was a
pronounced "butterfly" veined one of delightful form and color, but the
stalk was about 40" tall and snaked all over the ground.  I enjoyed it
anyway, but it was as sterile as could be.  I think it was from Reginae
pollen on one of the anthocyanin-pigmented species, possibly one of the
*pallida* variants.  I did have several others also, such as *perrieri.*
I've forgotten much in the intervening years, and found the whole attempt
frustratingly unproductive--equal to my experience trying to set seed on Wm.
Mohr, Oyez and Present.

Looking at those succesful products of the past, few of them have been from
species materials on the diploid side.  An example is the Cordelia (diploid
hybrid) X Macrantha, one of the collected species tetraploids. DOMINION, in
the ancestry of almost every tangerine-bearded, red, brown or blended iris,
is the only product of that cross of which I'm aware.

and many others are nearly all diploid x tetraploid crosses.

Several significant diploid X tetraploid hybrids were emerging also in
France in those early years, many of them highly colorful and in the
heritages we now enjoy.

SNOW FLURRY is remarkable as it is from a pod on Purissima (tet) X the
pollen from Thais, a tall pallida-pink diploid of high quality for its time.
Ordinarily, diploid pollen on tetraploid pod parent is not a successful
cross type.  It may be that the double-chromosome pollen grain from the
diploid is heavier and slower to grow than the normal haploid, one
chromosome set, pollens, leaving nothing for the doubled grain to fertilize.
Few of the hybrids are of this type, but Snow Flurry is not the only one

Despite its three-quarters diploid ancestry, I found Snow Flurry a difficult
one to keep going in Idaho winters.  It was quite susceptible to Botrytis.
Every year a significant portion of the stock would succumb, despite all
efforts to prevent it.

Orville Fay's use of *pallida* in his pink breeding to attempt to import
virus resistance and that healthy, lovely blue-green foliage of the pallida
types was successful, but how many years, how many tries he made to get the
cross to produce seed he never said to my knowledge.  Snow Flurry and NEW
SNOW, a seedling from Snow Flurry crossed with its hardy cousin, KATHERINE
FAY, are also mixed into the Fay/Moldovan/Rudolph pinks ancestral to nearly
all modern pinks.  The Snow Flurry foliageis quite like the *pallida* types
and contribute hefty qualities of virus resistance, texture, foliage health
and the like to many of its descendants.

Linda Mann's experience with her pallida offspring stirs the imagination.
It may be that stress factors heighten reproductive processes.  Linda's
conditions certainly do provide those stressors, as she has often
remarked--and survived through sheer grit and determination, qualities I
value quite highly in her.

Linda and others speak of reaching back into the collection of hardy,
healthy survivors among the historics as co-parents with the superlative
modern, but often difficult, varieties, approaches the diploid x tetraploid
gain from a different direction.  Those survivors are closer to those
original unbalanced crosses that were successful.  The sought-for qualities
are already present in them, so the strategy of their use builds on the
successes of others, already proven in value, rather than attempting to
recreate them.  I think this worthy of considerable thought.

One of the historics that may be especially useful is BLUE RHYTHM.  It is
only a few generations from species ancestry, although part of its heritage
is either unknown or unrecorded.  One quality that catches the attention is
the bud count and branching, resembling *I. trojana* to a suggestive degree.
I would be surprised if this wildling were not in Blue Rhythm's heritage.

Few of our modern varieties have the combination of luminous color, decent
form (for its time), and superlative growth habits, branching, bud count and
response to quality cultivation that we find already combined in Blue

There is an addition hidden potentil in the variety.  Melvina Suiter's
OCEANIC was extraordinarily wide in the haft, and was a seedling directly
from Blue Rhythm pollen on her own SUN LAKES, one of the sources of her
blue-bearded whites.  One should not have to go generation after generation
trying to recapture modern quality from Blue Rhythm.  The genetic potential
is there--as well as the disease resistance, growability across a broad
range of climates, soils and conditions, and, simply, charm.

Neil Mogensen   z 7  Reg 4  western NC mountains

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