Re: Bearded-beardless crosses
- To: Multiple recipients of list <i*@rt66.com>
- Subject: Re: Bearded-beardless crosses
- From: B* S* <B*@hsc.edu>
- Date: Mon, 23 Feb 1998 12:59:21 -0700 (MST)
> On one occaision, I crossed several pallida flowers with cristata in
>both directions and did not wind up with any seed. I also do not know
>of anything other than a paltec, the pallida tectorum cross. I though I
>heard Tomas Tamberg mention using gracillipes in some crosses he made
>with beardless, but I may be inventing it.
> Enough of musing, here is the conjecture: If the pollen could manage to
>fertilize the egg cells and seed was obtained, the odds of that seed
>being viable is pretty slim due to sheer amount of genetic material that
>is different. When speaking hypothetially of Bearded\Beardless crosses,
>it is my belief that these kinds of plants have the potential to
>increase negative traits as well increase positive traits. For example,
>Paltec is, from what I have observed, more succeptable to rot than its
>parents. It would be nice to have water tolerant bearded-looking iris
>(If you like that kind of flower), but the liklihood of the genetic
>crossover creating a plant that can grow in neither environment seems
>the most likely result.
> Just a thought. Was that hard to follow?
>Andrew
A few additional crested-bearded hybrids have been produced but none have
made it into the commercial world. Just based on looking at plants,
tectorum and milesii seem to represent a separate branch from the
cristata-japonica family with their thin, stoloniferous rhizomes. Perhaps
the tectorum lineage is closer to the bearded clan.
Andrew's thoughts are right on the money from a genetic standpoint. The
liklihood of a cross diminishes exponentially with the genetic
differentiation between the parents, and the chances of getting a
successfully developing seed are still slimmer.
Species exist to protect highly coadapted gene complexes. When those
complexes are broken down by hybridization, the usual result (at least in
the first generation) is a poorly adapted or sterile individual. There
are, of course, exceptions.
I'm afraid that without some form of new biotechnology (protoplast fusion?)
bearded-beardless hybrids are just pie-in-the-sky.
Anyway, do we really want them?
Bill Shear
Department of Biology
Hampden-Sydney College
Hampden-Sydney VA 23943
(804)223-6172
FAX (804)223-6374
email<bills@hsc.edu>
