Quote:
Originally Posted by SouthPark
True Roberta. Although - if cost and effort etc wasn't a factor (eg. even massively expensive equipment and incredible cost of testing), then the question I'd like to ask somebody out there is --- would some particular lab in the world today have the capability of doing a DNA comparison match between a confirmed cultivar and a under-test plant?
That would be my question to anybody that can answer that one.
Naturally - if prohibitively expensive (and things like that) ------ then this will be a good reason for the no-id verdict, with current technology.
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The answer is that there are many impediments to establishing a cultivar’s genetic identity that do not exist with pure species.
As a rather contrived example : Most orchid cultivars are complex. If a test establishes that a certain hybrid is ,say, 30% Cattleya Labiata, does that mean that it’s ancestry featured one crossing with a parent of that species, or 3 crossings with different hybrids which themselves were 50% C. labiata, or something in between. And remember that these various crossings with a parent with C. labiata may have occurred at any time in the long and complex history of a cultivar and all of its antecedents.
In other words, there are many ways to achieve a 30% mix of C. labiata and all of them will be different cultivars.
So from that necessarily reductionist example we can see that the only time the genetic test would be definitive would be if we could absolutely guarantee that both subjects had only two parents and no more, and each of those parents must have been a pure species. If we knew that, it’s unlikely we would need the test anyway.