permanent clones??

Jim McKenney
Mon, 05 Jul 2004 14:45:12 PDT
This is one of my favorite topics, and I'm glad that someone else has
raised these questions again. 

I used to receive a catalog from a well-known commercial supplier of fruit
trees. In that catalog, not only was the variation in clonally propagated
material noted, but furthermore the variations were identified (somewhat
confusingly to those of us used to the usual meaning of the term) as
strains. For those of you not into this stuff, the term strain typically
refers to seed propagated material (rather than clonally propagated
material) which varies within only narrow limits. Or am I mistaken: is
there a parallel history of usage of the word strain among those such as
nurserymen and tissue culturists who deal with clomally propagated material?

At any rate, as I pointed out in an earlier post, the meaning of the term
clone seems to be changing. The older, seemingly original, meaning is being
abandoned in favor of a meaning which emphasizes the purportedly absolute
similarity of the elements which make up the clone. Yet as anyone who works
with clonally propagated material knows, such absolute similarity is an

These two different meanings not only introduce an element of ambiguity,
but they are also in some respects mutually contradictory. 

Jim McKenney


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