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Re: HYB: Selection Ratios

--- In iris-talk@egroups.com, Sharon McAllister <73372.1745@c...> 
> Betty in Bowling Green wrote:
> <<
> Once upon a time, people said you could expect about 1 in 1,000 to 
> introduction material.  That is, of course, if introduction is your 
> Now "they" say you can expect more like 1 in 100. If you read the R 
& I's 
> carefully, you may have reason to question even those figures. >>
> I've heard different stats quoted for different types, which 
strikes me as
> quite logical.   Of course, a beginner should NOT expect the same 
> that someone who's been working 20 years would get -- because 
there's a
> learning curve to contend with. 
> Henry Danielson, who worked for decades with both TBs and ABs, gave 
me the
> 1 in 1000 rule of thumb for TBs and 1 in 100 for ABs.  I'll leave 
the TB
> discussion to those with more experience, but from personal 
experience I
> can tell you a lot more about working with ABs.
> I analyzed Gene Hunt's records for roughly the last 10 years of his 
> decades of hybridizing.  This was after the impact of his ESTHER, 
> on the arilbred world had become obvious and during the period in 
which he
> had focused his work on arilbreds.  I found his selection ratio to 
> consistently better than 1 in 100, but never as much as 1 in 50.  
> After that, I not only went back to analyze my own early records and
> started running stats of my own results.  I hasten to add that I 
> these when I FINISHED evaluating the seedlings from a given year, 
so that
> my "to introduce or not to introduce" decision will not be 
influenced by
> the numbers. These records show that I grew thousands of seedlings 
> introducing the first one and it took me more than ten years to 
reach the 1
> in 100 level.  [I should probably add that I believe it would have 
> much longer, had I not had Gene's stock to work with.]  
> As the years have passed,  I've also gone back to play with 
some "what if"
> scenarios.  Looking at a year in which the number of final 
selections was
> influenced by the space available:
> 1.      How many contenders were in the final round?  How many 
would have
> been kept with unlimited space and resources?
> 2.      How many were in direct competition?  [Same type, similar
> appearance, so only the best performer would have been introduced.]
> Even this hypothetical ratio has never been better than 1 in 50. 
> Individual crosses, yes.  Some have produced less than 50 
seedlings, with
> one or more introduced.  BUT these were balanced by other crosses 
> produced NOTHING worthy of introduction.  
> I could go into detail about the differences between line-breeding 
and wide
> crosses, but doubt that many would be interested.  If you want to 
see some
> of this for yourself, I've posted my Breeder's Digest and some other
> records on my website:
> http://www.geocities.com/~smcallister
> That's the home page, where you can choose between cultivar lists 
> photos], hybridizing, reference material, or a photo gallery.  In 
case it
> isn't obvious, breeding records are in the Hybridizing Section!
> Sharon McAllister

Sharon --

I for one would be VERY interested in the differences you found in 
this regard with line breeding vs. wide crosses.  The consensus seems 
to favor the former, but the latter interests me more.  Without 40 
more years to spend at hybridizing, though, what do you think my 
chances are?  (My hybridizing goal is pink TBs without tangerine 
beards, even in the throat.  Preferably blue, white, or true pink 

Patricia Brooks

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