Re: Re: squalens, sambucina etc (a bit long) (was Iris pallida cultivars & nomenclatural question)

From: r*@sbcglobal.net
To: i*@yahoogroups.com
Sent: Wednesday, June 30, 2004 9:46 AM
Subject: Re: [iris-species] Re: squalens, sambucina etc (a bit
long) (was Iris pallida cultivars & nomenclatural question)
 
"First off the top of my head many early whites were the result of Iris kashmiriana breeding. I seem to remember that it was believed to be more dominant that what had existed before but my memeory is fuzzy on that. I am not even sure anymore that I really know what kashmiriana is. We have discussed this before."
 
Bob, even though this was addressed to Dave, please let me comment on some specifics involving whites--from tetraploid experience mostly.
 
The early dominant whites of the 'Purissima' sort derive their genetic pattern primarily from 'Kashmir White' which is of uncertain origin.  It *may* be from a white form of *Iris kashmiriana.*  What is certain, however, is that the same dominant inhibitor of *pallida* blue can be inherited either from the non-blue 44-chromosome sterile IB sorts derived from *lutescens* (Lam.1789) on the rare occasions tetraploid offspring can be obtained.  More recent SDB's from TB x *pumila* origin sometimes also contain the factor hidden behind the pumila anthocyanin pigment, so advanced generation hybrids into TB stock can introduce the dominant inhibitor.  On this basis some have speculated that 'Kashmir White' may owe its inhibitor to dwarf ancestry.
 
In support of this interpretation I might mention a cross of 'Garnet Treasure,' an early red-violet SDB from 'Minnie Colquitt,' X a blue Suiter seedling from (Sun Lakes x 'hoogiana,' a blue form I believe) which yielded half odd pale blue near-whites with no pumila fall spot, and half medium violets with the spot.  There were about thirty seedlings bloomed from the cross.  The simplest and most probable interpretation is that the violet SDB brought one dose of the inhibitor into the array.  Since the seedlings were unbalanced sterile IB "arilmeds" the interpretation could not be tested.
 
There appears to have been demonstrated in TB's at least two different whites of recessive origin in addition to the "glaciata" type, which, when crossed, do not yield all whites.  One of the whites is exemplified by Melvina Suiter's 'White Satin,' a sib to 'Sun Lakes,' a blue from blue parents.  'White Satin' was registered in 1950 and is from (Blue Champagne x Sylvia Murray).  'Sun Lakes,' due to an oversight, does not appear in the registry until the *Iris Check List* 1979, but is from the same time period. A cross reported by Vallette of 'White Satin' with 'Matterhorn,' a glaciata, yielded a variety of anthocyanin color types and a couple of plicatas and whites.  There are other derivitives of 'Gloriole' of the same type white as exemplified by 'White Satin.'
 
The other recessive, non-glaciata, white is typified by 'Dayspring.'   The *aphylla* clone 'Ostry White' may be the same as one or the other of these, or be of a third type.  A post to "Iris-talk" some months ago mentioned a cross of a white with 'Ostry White' which did not produce whites.  I cannot for the moment recall with certainty whether the post originated with Harald Mathes or what was the identity of the other white. 
 
There is a discussion of the question of various whites (rather, non-blues),  in TWOI on pp. 401-403 and ff., probably authored by Keith Keppel.  He is one who can speak with authority on this matter, incidentally, and probably can point one to the taxonomic data you seek.
 
I have assumed the whites of the 'White Satin' type to have derived their genetic white type from *Iris pallida,* although I know of no simple way to test that assumption.
 
On a related matter to the above, I might comment that the karyotypes I've seen published for *Iris variegata,* *pallida,* and *kashmiriana* are very similar, suggesting that these Eupogons, and probably many other of the Asiatic tetraploids, are of very close evolutionary relationships.  An exception might be *Iris trojana,* which has some characteristics of a rather distinct sort.  The clone I had from L. F. Randolph resembled a more primitive 'Blue Rhythm,' with the same deep branching and very similar form.  It would not surprise me if part of the unknown part of the ancestry of 'Blue Rhythm' did not include one or more inclusions of *trojana.*  Other than this exception, it would surprise me if all the other collected tetraploids were not actually variants of the same species, even though they originated from areas as remote from one another as Afghanistan, Turkey and the European mainland.
 
I am in the hope that the molecular studies you mentioned recently can eventually untangle the nomenclature and affinities of the various collected tetraploid Eupogons and their relationship(s) to the *pallida/variegata* complex.   Even though many of the actual species clones are no longer extant, their first generation hybrids are, and might possibly be useful in determining the relationships..
 
Neil Mogensen  z 7 western NC

Yahoo! Groups Sponsor
ADVERTISEMENT
click here

Yahoo! Groups Links
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index