Re: Genetic Diversity

Nigel Hurneyman (NHurneyman@softwar1.demon.co.uk)
Tue, 17 Dec 1996 13:26:46 -0000

I think I agree with the conventional view that plants brought into captivity
will generally evolve to suit the conditions of the captivity, generally with
loss of genetic diversity (although I have anecdotal evidence that this isn't
always the case).

For a hobbyist, this can be a good thing - there seems to be a theory that
one strain of Darlingtonia has proved more amenable to horticulturists, so
more people can now grow and enjoy these plants.

For a reference collection, this sort of evolution is dubious. If it helps to
keep the plants in cultivation that is good, but not at the expense of their
botanical characteristics diverging significantly from wild populations.

As a security against wild populations becoming extinct, this sort of
evolution is clearly undesirable - I believe that reestablishing plants
in the wild is the only long term solution and that can only be harmed
by allowing genetic divergence from the original wild material. The
importance of the wild ancestral potato recently came to prominence
because it has disease resistance that has been bred out of current
cultivars.

Dave Evans expressed the thought that 'Even a very small population can
become very different from other populations within only several generations'
- can anyone put some sort of figure on any instances of the number of
generations?

Regards, Nigel Hurneyman