Gladiolus xgandavensis
Tue, 23 Aug 2005 00:08:09 PDT
Jim McKenney wrote>
> Was it such an important point I missed? I would say in rebuttal that
> perhaps the taxonomists missed an important point. When two plants which
> nominally the same species produce such different progeny, that should
> into question the taxonomy. It seems to me that the disparate breeding
> results ought to be telling the taxonomists something, perhaps something
> they do not want to consider.

I think the point here is that although versions of one species, G. dalenii,
were used to create hybrids and to form at least two lines of descendants
("x gandavensis" and "Primulinus"), they were crossed onto previously
existing hybrids, so that it is very difficult to predict how the genes will
be expressed in such cases. I also think that selection must have played a
big part in maintaining the petite form of the "Primulinus" cultivars,
because it is clear that the yellow coloration was also speedily passed into
the large-flowered cultivars in which there is no visible trace of the
hooded flower of G. dalenii. One must never overlook the powers of
artificial selection in causing rapid divarication in lineages of
domesticated plants or animals, neither do we see the forms that have been
discarded along the way.

As for the taxonomic unity of the protean G. dalenii, the species has an
extremely recognisable look in all its forms, deriving from that famous
hooded segment, arching over the reproductive parts. I've seen it in
numerous places in eastern Africa, from the Drakensberg to northern Kenya
and have never been in doubt as to its identity.

Interestingly, the G. garnieri mentioned in a post by Brian Whyer, is
another version of G. dalenii. The name pertains to plants originating in
Madagascar - if the plants also come from there this stock is the only hardy
plant I know from that extraordinary island.

John Grimshaw

Dr John M. Grimshaw
Garden Manager, Colesbourne Gardens

Sycamore Cottage
Nr Cheltenham
Gloucestershire GL53 9NP

Tel. 01242 870567
Mobile 07 919 840 063
Fax (Estate Office) 01242 870541


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