HYB: Tetraploid Nomenclature

Tom Tadfor Little wrote:

:   I. pumila is not a very good
:   example of an autotetraploid, because it apparently resulted from a natural
:   hybrid of I. attica and
:   I. pseudopumila, so that two of its chromosome sets are noticeably
:   different from the other two (refer to the idiogram on p.152 of _TWoI_). A
:   purist would probably describe I. pumila as an amphidiploid or at least an
:   allotetraploid. However, the attica and pseudopumila sets apparently pair
:   very readily, so for practical breeding purposes I. pumila behaves like and
:   autotetraploid.

Guess that will teach me to write about non-aril/arilbred iris from memory!  Tom
Wilkes once described Stol-pums as true amphidiploids.  Perhaps this was because
I. pumila BREEDS LIKE an autotetraploid, even though it really isn't one.  I bow
to the median experts on this subject....

:  What breeders need (and don't have) is a standard terminology for plants
:  that _breed like_ autotetraploids, amphidiploids, or unabalanced
:  tetraploids, even when those terms are not technically applicable because
:  of the multiple species involved in their background.

Well, we do have the tongue-twister "amphidiploidlike-hybrids" for the ones that
behave like amphidiploids, and "homologous tetraploids" that behave like
autotetraploids even though they are derived from different species....   And I
rather like Ben Hager's "heteroploid" for the unbalanced ones.

Sharon McAllister (73372.1745@compuserve.com)
Who doesn't have any easy answers on this one, either.
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