Re: fertility of mixed crosses with aphylla based iris

 

Dear Vicki;

 

            I am probably just being a curmudgeon. Obviously we both understand the term Amphidiploid. Of course defining it for other lurkers learning on this list is good. One point, although amphidiploids are not a strict 4X chromosome number, some geneticists define it as a special case form of tetraploidy, since they have four sets of chromosomes. This is why I was unsure as to how it was being used.

            I looked at the parentage of ?Arrival? and it seems very very likely that it is a 48 chromosome plant. The scientist in me says never assume too much, so I suppose it is dangerous to say that absolutely, until it has actually been counted.

            The point I was trying to bring forward in my clumsy way was this is not what one expects from an SDB and is not part of the fertile family that composes most SDBs. It obviously is an innovative hybrid and should be celebrated as such, but maybe we should be using another term. Of course the category SDB is based on size. And no doubt this fits that qualification, but considering its background, would it be more logical to retain it in a SPEC-X category. Because, as I pointed out, it probably would produce less fertile offspring when crossed with normal SDB?s.

            As hybridizing becomes more sophisticated and complex perhaps we need to re-evaluate some of our traditional classes. It seems to me we already have some huge disparities when including horned TB?s with Classic TB?s. In the eyes of some they are anathema. This is their problem, but I do understand that people expect a certain model for each classification. Perhaps we need a larger number of categories. When I present a judge?s training, one of the most important points I try make is how to evaluate a plant as a garden plant without using a formula for each class. The formula for each class tends to create paradigms that create a cookbook effect, following a recipe laid out for a particular classification. This tends to minimize the underlying fundamentals which is the basis for the cookbook originally. Since I do lots of judge?s trainings on species and species crosses no formulas can be applied which cover all types of Irises in these groups. They resist working as recipes for evaluation and judges are forced, possibly unsuccessfully, to think..

 


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