Re:HYB: another blend (photo posted

Chuck Chapman's notations are excellent study material here.  His
reference to Kenneth Kidd's chapter in TWOI is very important, even
though the material there is guaranteed to give one a headache at first
(if not forever!).

Chuck's material here is worth printing off and putting beside one's TV
chair to read during commercials, the sound off.  That's the reason for
the "mute" button!  Make that near-half-the-time useful......

The inheritance in tetraploids is *very* complex and depends, among
other things, on whether the pairing is selective (one chromosome will
pair only with one of the other three from the set of four) or not
selective (any combination of the four--including multiple or complex
joining that includes three or even four of the chromosomes in the set,
linked together in complex ways), as well as the distance of the DNA
sequence for the factor from the centromere (the wasp-waist "middle" of
the chromosome, regardless how unqual the two "arms" are).  The
illustrations in TWOI are minimal, and may or may not inform the reader
adequately.

This complexity is the result of the close evolutionary relationship of
many of the ancestral species involved in our modern hybrids--and the
somewhat more distant relationship of *Iris variegata* and its
subspecies from *pallida* and the Asiatic tetraploids, which seem rather
closely related to each other, despite phenotypic differences
(=differences in type, or appearance, such as in branching type, paper
spathes in *pallida* but not in the wild tets I have seen).

Species *pallida* obviously has adapted to a different climate, or be a
separate development from the diploid ancestoral type that lies behind
the entire Eupogon array.

The x=12 Balkan dwarfs, along with *aphylla,* are a divergence.

The Mediterranean x=8-chromosome dwarfs (*attica,* pseudopumila* and
*pumila*) add further complexity, but clearly are related in an
evolutionary way to the larger Eupogons.  It would seem they may be an
early or older divergent type, suggested by the chromosome reduction
from x=12 to 8.

On the IMM seedling being a Progenitor-type amoena, Chuck's
interpretation makes more sense than that of a pale umbrata.  The
presence of the factor in the ancestry is suggestive, and certain would
be hidden behind the dominant reduction of anthocyanin involved (what
used to be known as "I") in the intermediate generations would indeed,
as Chuck points out, mask the presence of the factor.  He is quite right
that it may be TTTt, yet still produce tttt offspring.  The event of
that type is rare, however.

It is possible for a flower to have both a faint cream, or faint cream
amoena yellow at the same time as a banded yellow pattern.  A number of
varieties have this.  The lack of significant yellow in the standards
except in the base and right at the edge, although pale, says "banded"
to me.  The pinkish anthocyanin color often is the result of the violet
(pale) anthocyanin combined with a pale yellow wash.

Yellow genetics is complex.

Neil Mogensen  z 7  Reg 4  western NC mountains

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