HYB: question - aphylla, black, hafts

I have a reputation for telling folks "more than they ever wanted to know."--a
quote from my pre-seminary evaluation in the parish in Oregon I belonged to.
They meant it both seriously and in good fun.  "Never ask Neil a question,
he'll tell you...."

I laughed.  It was true.  So to your question:

It may be helpful in looking at your question to look at the mechanism of
"blacks" that appears to come from aphylla.

The anthocanin molecules in "blacks" and intense purples is due to two pieces,
one structural, the other biochemical.

First, the cell surface appears to have a lens-like effect focussing the
light--and the eye on an elaborate cluster of anthocyanins just at the focal
point.

The second is that a particular protein lies at that point that acts like a
pin-cushion for attachment points for the anthocyanin-sugar-protein combo that
makes up our pigment(s) in the anthocyanin cluster of variants.  The effect is
a dense, large clump of anthocyanins called an "Anthocyanin Vacuolar
Inclusion," AVI for short.

This is in addition to the normal violet pigment distribution.

Because of a surface cell difference(s), I suspect, between falls and
standards, the effect is significantly more visible (if not significantly more
developed as well) in the sepals/falls than in the true petals/standards.

Keppel's work with the "black plicatas" shows that AVI's can and will occur in
plics as well, but he must really have gone through a lot of compost to get
his results so far, I think.  Talk about persistence!

Now, about half markings.  We're talking about several different genetic
elements, I suspect.  One of those is the variegata-derived linear array of
fall anthocyanins being in the mix.  This being present is a sure way to have
significant haft markings.  Many blacks may be occult (ie. hidden) umbratas in
addition to what else they are.

From my own observations with clean falled-darks, and in Romantic Evening and
its children, grandchildren, is that there are two concurrent pigment
distributions in the seedlings.  One of them has no marks, the other does.
Looking closely at the hafts, there is a pattern of slighly lighter coloring
where one would normally have plain white lines if the other, more-or-less
concealing pigment, were not present.  The two combined do give a very clean
effect.

Probably the cleanest, nearly perfectly unmarked black I've looked closely at
is Wild Wings.  It is extraordinarily clean, as I recall.

Most blacks seem to have the at-least-double distribution of anthocyanins
involved, one of them being the one involving the AVI's.  I think both
contribute to the depth of color.  They are most likely linked, the AVI not
likely to be present in the absence of a fairly full violet-purple to start
with

Have I illuminated the question?  Or clouded it further....

Neil Mogensen  z 7  Reg 4  western NC mountains

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