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HYB: Selection Ratios


Betty in Bowling Green wrote:

<<
Once upon a time, people said you could expect about 1 in 1,000 to be 
introduction material.  That is, of course, if introduction is your goal!  
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 results
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 four
decades of hybridizing.  This was after the impact of his ESTHER, THE QUEEN
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 be
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 compiled
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 before
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 taken
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 that
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 [with
photos], hybridizing, reference material, or a photo gallery.  In case it
isn't obvious, breeding records are in the Hybridizing Section!

Sharon McAllister


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