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HYB: 'A roll of the dice' augmented

From: Sharon McAllister <73372.1745@compuserve.com>

Mike Lowe wrote:

>  In studying thousands of tall bearded pedigrees I am struck with the
>  degree of randomness implicit in the actual pedigrees versus the focus
>  suggested in talk and articles about breeding goals.

The true test of this would involve the analysis of an individual's plans,
actual crosses, and final selections.  More about that later -- but I can
think of a couple of things that do contribute to Mike's perception.

1.      Some hybridizers talk or write at length about plans, but then find
they can't follow through.

As Keith Keppel described the problem in the April 1968 AIS Bulletin: 

"Once upon a time I would make copious notes during the winter time,
listing all the crosses I would make in the spring.  Of course the desired
varieties almost invariably failed to bloom at the right time.  Or bloom at
all.  Or have pollen.  And very often when I went to make the specific
cross, I would suddenly realize that both of the projected parents carried
undesirable traits."   

And his solution:

"Now instead of planning to cross specific varieties, I plan crosses of
lines.  My notes will give instructions to 'cross best of plicata-blooded
bicolors X strongly marked yellow-ground plics', or 'cross least ugly
ice-whites'  (the scientific urge coming to the fore -- experimental cross
material!), or 'use best MORNING BREEZE-BABBLING BROOK cross blues with
red-bearded whites and orchids'.  These notes tell me on which lines to
concentrate without pin-pointing specific impractical or impossible

2.      Some hybridizers put a great deal of study into developing their
plans, but are highly secretive.   

No published quotes supporting this, obviously -- but think about how many
hybridizers don't write for publication.  Or even include pedigrees on
seedling labels, lest a garden visitor learn some secrets.

Now to return to the analysis of one hybridizer's records....

If you carefully examined the pedigrees of all of my registrations and
introductions so far, without access to my hybridizing plan or seedling
records, you'd probably conclude that I like to spread pollen about at

If you compared the comprehensive plan I wrote in the mid-1970s with my
introductions through the 1980s, you'd probably decide that I'd given up on
much of my program.

But if you had the original plan and complete records of crosses, as well
as the seedling evaluations that led to all of my R&I's to date -- you'd
understand a lot more.  You'd spot the line I abandoned, and know when &
why.  You'd see which ones turned out pretty much as expected.  And you'd
notice a few that bore unexpected breakthroughs.

In my opinion, the true test of a hybridizer is the ability to recognize an
unexpected breakthrough and take advantage of it.  Case in point:  Paul
Cook and PROGENITOR.   

Cook's overall program was a model of carefully planned, practical
experimentation.  He delved into the genetics of iris and was one of the
first to recognize the importance of tetraploidy and undertake a planned
program to produce a new race of improved tetraploids.  

TWOI tells the story but, briefly -- PROGENITOR was an unexpected
breakthrough in a program designed to create bluer TBs.  Some of the I.
mellita Cook had obtained turned out to be I. reichenbachii.  Many
hybridizers would have simply discarded seedling #1346 because it didn't
fit in with the program's objectives [and it's often been described as an
iris only a hybridizer could love], but Cook recognized it as something
previously unseen -- a dominant amoena -- and aptly named it PROGENITOR. 
Today, it's hard for us to imagine the world of iris without this line.

>  I am coming to the reluctant belief that this dichotomy is a result of
>  tetraploidy. We really are rolling dice. When examining diploid
>  whether animal or plant, a clearly discernible structure can be posited
>  pedigree research. This structure is just not there in tetraploids.

I do like the analogy of rolling dice -- but in my experience a structure
does exist in tetraploids.  The catch is that it's so much more complex
than that of diploids that it's extremely difficult to discern and quite
challenging to use.  Personally, I think the effort is worthwhile but do
admit that there are times when total disregard for structure turns out to
be an advantage.  Just think of  the beginner who makes a cross the experts
would dismiss because the odds are overwhelmingly against success -- and
succeeds anyway.

Sharon McAllister

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