HYB: Umbrata trait and origin

Looking at the photos of species cv's on the HIPS "Quick Fix" section of AMAS,
*Iris trojana* and others, I wonder if perhaps what we have been calling
"Umbrata"--the fall-overlay of color in the surface of the fall
tissue--originates from multiple sources.

Many of the first generation tetraploids were Umbrata-type bicolors,
particularly those associated with DOMINION.  I had originally assumed we were
looking at the fall overlay pattern of *Iris variegata* in early discussions
of "Umbrata" patterns, but now I wonder if what we see in *variegata* is
simply an extreme form at one end of a scale that includes the solid fall
overlay patterns on the tetraploids.  The early hybrids would then quite
possibly be inheriting alleles of the same Umbrata series from both parts of
their ancestry.

There is no reason to believe that the genetics of the diploid Eupogons (true
beardeds) is essentially different from those of the tetraploids.  The hybrids
are certainly fertile enough, and do not act like amphidiploids.  The behavior
appears to be a mix of auto and allotetraploid effects.

I think this implies the separation between the ancestral diploid forms behind
the Asiatic tetraploids and the more northern diploid species of *pallida* and
*variegata* represents a substantial passage of time with a high number of
generations of separation--probably dating from early in the European
glaciations.

The growth cycles of the tetraploids and those of the hardy Europeans differ
enough to support that.  Winter-active southerners and summer-active northern
materials are interfertile but sometimes difficult to grow in the same
garden.

Neil Mogensen  z 7  western NC mountains

---------------------------------------------------------------------
To sign-off this list, send email to majordomo@hort.net with the
message text UNSUBSCRIBE IRIS
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index