RE: Another tetraploid SDB

I have been very interested in the Craig's 48-chromosome *Iris aphylla* hybrids for some time, hybrids which range from dwarfs upward toward TB type and height.  What a wealth of material!  I have been very interested in the photos posted recently by Sterling Okase and in those the Craigs publish with their brief but rich catalog.
 
There have been a number of times in the history of our modern iris that *aphylla* ancestry has entered into the development.  Each time, it seems, the heritage becomes richer by the species' addition.  I applaud the Craig's persistance and effort.
 
The *aphylla* hybrids are utterly different from the amphidiploid SDB's developed from TB X *pumila* crosses.  For one thing, the backcrosses to TB's result in a far more fertile type IB and allows inbreeding at the IB level, a previously very difficult option.  Lynn Markham's charming selections illustrate the potential in such crosses.
 
There are a host of possibilities yet to be explored, particularly in incorporating other 12-chromosome genome species such as *timofejewii*, *astrachanica*, *albertii* and the like.  Peyrard's *timofejewii* X *variegata* seedling thrives here in mountain North Carolina, as do Bea Warburton's Astrachanica Kalmikij, the yellow form of *Iris reichenbachii* and Lowell Baumunk's charming PETIT LION clone of *Iris variegata* and to a lesser extent, *pallida* LOPPIO.  My attempts at crosses using these divergent materials is made more complex by many being diploid, a few others tetraploid such as the *aphylla* clones and Marham's hybrids.  I would be tempted to follow Martin Weber's thought about chromosome doubling as a means of facilitating hybridization but I admit to an excess of caution.  I might not live long enough ever to see spontaneous unreduced gametes, the only alternative, as unreduced gametes are presumably quite rare, I believe.
 
A friend working at the local Experiment Station in tomato research first called my attention to Kevin Vaughn's published paper(s) on Oryzalin (Treflan, etc.) as an agent used in polyploidization.  I can count on help from him should I attempt such use, but due to the number of domestic pets in the immediate neighborhood and my own reluctance to work with radically toxic chemicals at this time prevents me from pursuing the possibilities.  So, for the time being, I plod along, tweezers in hand, getting down on my knee-pads my daughter gave me and trying yet again for the near impossible "takes" in such hybrids.  My total so far--one selfed pod on Petit Lion, from which I expect only minor variations on the species.  I intend to keep trying.
 
Neil Mogensen  z 7  western NC

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