Re: [SpaceAgeRobin] HYB; Questions

You forgot the third possibility. That is partial dominace. Under this theory  the protohorns would be 2 sa genes and horns three and possibly flounces four sa genes. As the genes have been around since like, forever, they would be thouroghly distributed so many plants ( as with pbf) will havesome genes and like PBF, was considered to be dominant until a closer look was made of it.

As the the Thornbird pedigree. Only the crosses producing SA plants were used. Any crosses not producing SA plants were not used so data does not suport dominance. I could build a similar chart with PBF.

The ratios produced fit a partial dominance idea better then a complete dominance theory, without invoking a second set of genes ie: Normalizer gene or suppressor gene. The variation of  expression also fit this idea as with PBF were the expression of feature depends on environment and climate. This variation in expression is not seen in dominant gene or recessive gene control.

Chuck Chapman 

"Neil A Mogensen" <neilm@charter.net> wrote:

>Bob, for the most part I am in complete agreement with Chris in his response
>(where he typed before "Send."---my typical error of this type is to go hit
>the X in the square box in the upper right INSTEAD of the "Send."  That
>doesn't work so well, and the material just typed can't be retrieved (no
>trash can for this--that is, unless someone else knows something I don't
>about Outlook Express....which wouldn't surprise me a bit).  So I either
>forget about sending, or I start over and do it all again.
>
>The SAGE project is designed to look at questions of development and
>inheritance in SA's.  You might very much enjoy taking part, and produce
>some name-worth SA's while doing so.
>
>This is a multi-year, multi-national project in which we are in our very
>first stage looking primarily at two questions so far:  dosage, and the
>possible presence of an Inhibitor or Suppresor (Normalizer) enzyme system or
>set of genes that prevent SA expression.
>
>The reason for suspecting the "normalizer" thing is that the SA condition is
>quite clearly a dominant.  Provided one counts the "protohorn" as showing in
>ADVANCE GUARD, one of the Austin-used ancestors of most SA's in existence as
>being the minimal evidence of SA presence, cross-result counts rule out
>recessives as the primary factors in SA inheritance.  The percentages of
>SA's is too high, and the OTHER, non SA parent when crossed with some other
>non-SA parent that does also throw SA seedlings when crossed with them,
>don't produce SA's.  If it were a matter of recessives, some or most would.
>
>Austin noted that odd appendage at the end of the beard (present on many
>irises, especially those heavy to Sass-bred varieties in their ancestry).
>He took ADVANCE GUARD and a closely related seedling that had the same
>"protohorn" and began inbreeding them and came up with the first publicly
>offered, registered and named horned, spooned and flounced irises.  There's
>reason to believe that SA's had been showing up on occasion for quite a long
>time here and there, especially in the Sass seedling fields in Nebraska.
>But there are even suggestions in some very old records about diploids in
>Europe that suggest SA phenomena were showing up from time to time centuries
>ago.
>
>Horned, Spooned and Flounced irises--i.e., any obvious SA--when crossed with
>almost all mainline (non-SA) irises produce at least some SA seedlings.
>That says "dominant," but there are complicating factors, as Chris mentions,
>the percentages of SA seedlings that are obvious are lower than they should
>be for a "dominant."
>
>There may be several reasons for that.  1) the SA condition may well be a
>combination of genetic factors rather than a single "gene." [highly
>probable].  2) there may be a single dose of the possible "Normalizer"
>factor or set of factors that prevent SA expression in half or even
>three-quarters of the seedlings--perhaps. [almost certain:  evidence for
>this is a single fall of a single flower one time in Sutton's growing fields
>of a full-blown flounce on one fall, one flower, in their very large growing
>fields.  That cannot have occurred if the variety, WILD WINGS of Keith
>Keppel's, did not already possess all that is required to be a flounced SA.
>It isn't however.  The only explanation that is "Occam's Razor"-proof is
>that there is in WILD WINGS a condition that prevents departure from normal
>form.  A stray bit of radiation zapped a short piece of DNA essential to
>that prevention in the embryonic development stage of the stem tissues that
>developed into that fall with a flounce.  "Zaps" from radiation don't
>add--they either disrupt "codon" order, changing the gene, or delete it.
>Further suggestions of a "Normalizer" condition is that there are some
>varieties that NEVER or almost never produce SA offspring in the first
>generation.  Apparently WILD WINGS's papa, ROMANTIC EVENING is one such.
>
>Mike Sutton suggested several others from his memory, not his records, as
>having few or no SA's in their offspring, DYNAMITE being one.  There are
>several others in the SAGE project plan, back several months in the archive
>(hort.net) and in the AIS *Bulletin* article, "Getting Serious about ...."
>SA genetics, which lays out the plan in its initial stage for SAGE and
>mentions several non-producing varieties.]
>
>As to the Dominant status of the SA condition, I suggest you look at the
>THORNBIRD pedigree chart on the HIPS website.  You can find it as a
>subordinate page either from the Dykes list or from "Quick Fix."  Once you
>access the photo of THORNBIRD, you will see a link to "pedigree" or
>something like that.  That brings up a .jpg chart that gives the ancestral
>tree back quite a few generations.  It is marked both for rebloomer parents
>and for SA's.  Beginning from early Austin SA's, every one, or at least
>most, of Thornbird's ancestral crosses was an OUTCROSS to a non-SA parent.
>That says "dominant" in spades.
>
>The SAGE plan includes four cross types which look for both the "normalizer"
>and for dosage effects.  Counts and counts broken down by appendage type in
>probably about an eight-division set of a lot of seedlings from each cross
>type should give some ammunition and information about what we are dealing
>with.
>
>Early SA X SA crosses gave so many distorted or messed up flower formation
>that the cross-type was basicly abandoned.  More recently, however, good
>SA's have come from multi-generation crosses including both outcrosses to
>"normal" irises and to other SA's.  The screwed up flower structure still
>does occur from time to time, but it isn't the issue it was once.
>
>As to breeding for quality SA's, I would suggest--get the best SA's you can
>find, watching for consistency of appendage as a significant issue, then
>cross these with the very best of the best of the mainline non-SA
>irises--branching, budcount, color, substance, width of haft (especially)
>and such.  YAQUINA BLUE has been very productive of SA's--including flounced
>varieties, for instance.  That means it would be worth trying SEA POWER
>too--it's a seedling from YB.
>
>Suttons are getting beautifully branched pink SA's with lace and all sorts
>of other qualities.  They've followed the idea of crossing out to the best,
>and inbreeding also among the best of the seedlings (as in Mike Sutton's
>BOTTOMS UP, a blue "dark top" progress step).
>
>Take a look at the Burseen offerings, by the way, and also Christopherson,
>Lauer and quite a few other folk  We don't have to do what every one else is
>doing.  How about a BLACK SA?  If you run into one of those non-producers
>and get no SA's in the offspring, USE those seedlings in breeding.  You will
>recover, almost for sure, from at least some of them, the SA condition in
>the next generation.  IF it is "normalizer," the gene(s) can be flushed out
>by going one, perhaps two more generations.
>
>As you suggested, using the best X the best is the way to go, but it doesn't
>have to be SA on both sides of the X.
>
>I hope you find some of this helpful.  Bill Burleson (Oneofcultivars) is no
>great distance from you--in NE Mississippi, E of Tupelo, and is involved
>both with this Robin and the SAGE project.  He's a wonderful resource.  If
>you haven't already made his acquaintance, you would find it profitable to
>do so, I believe.
>
>Neil Mogensen  z 7  Reg 4  western NC mountains
>
>SpaceAgeRobin Home Page at http://groups.yahoo.com/group/SpaceAgeRobin/
>The Robin's archive is at  http://www.hort.net/lists/spaceagerobin/
>
>

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