Date: 22 Jun 1998 13:08:20 +0100 From: Loyd Wix <Loyd.Wix@unilever.com> To: cp@opus.hpl.hp.com Message-Id: <aabcdefg2130$foo@default> Subject: Yet more on Nelson
Dear Jan, Michael et al,
thanks for the lively discussion!
>What is a subsp., var. or f. is not defined anywhere in the
>ICBN (OK, they are infraspecific ranks, but not even the
>meaning or significance of this fact is explained to any
>sensible degree).BTW: Yes, Michael, Stuessy writes a lot.
>But unfortunately (or rather, fortunately?) Stuessy is not
>a collection of rules that *must* be followed but only one
>of the numerous possible *opinions*.
And given so many options on interpretation inconsistency is
inevitable, if its problematic for plant taxonomists the
situations even hazier for the rest of us. What does appear
to be case is that this subject (f.chinopetra) is emotive
enough to induce an expression of opinion, in some cases
even without first considering the paper (Nelsons).
>Yes, the ICBN states the rules of nomenclature (the proper
>application of names to taxa), but the ICBN does not
>elaborate on how taxa are to be defined. I think Mr. Wix's
>discussion concerns the issue of whether it is reasonable
>to define anthocyanin-lacking mutants as taxa
Michael, first of all I apolgise for not acknowledging you
in my previous mail, but am pleased to see you have
continued to contribute anyway. My main discussion point is
the information provided in Nelsons paper on
P.g.f.chinopetra or P.g 'white flowered Irish mutant' if you
prefer. I am familiar with white flowered forms of other
plants a good example would be Orchis morio, the
Green-winged Orchid. The last remaining populations of these
plants in my locality (East Northamptonshire, North
Bedfordshire, England) consist of circa 10% white flowered
plants, but this is typical of this species else where in
England and I believe this is the case also on Continental
Europe. This fact is known and recognised so few are
surprised to find such white flowered individuals. (As a
digression for the Eco minded these last surviving plants of
this species in my locality are not found in pristine
country side but in an industrial setting - part of the
mainline Sheffield to St Pancras London Rail line. The
plants have only managed to survive at this site due to the
grazing activities of an introduced species the rabbit !).
The aspect which interests me over Nelsons paper is why pure
white flowered plants of P.grandiflora have only ever been
recorded from South Western Eire, and never from elsewhere
in the range of P.g. Afterall it has already been suggested
that such things are transitory mutants which will
eventually disappear for reason previously cited. However
the Burren plants have been going for at least 32 years
(compared to 160 years for f.pallida). They are
reproductively active and so their mutation (even if
recessive) will appear in future generations of the Burren
plants.
>If it could be demonstrated that such a reproductive
>mechanism in fact leads to separation of taxa (i.e. if
>other, genetically independent and distinct features are
>correlated with different flower colour), I would tend to
>believe that it has some taxonomic relevance.
Well for the curious this would be an interesting subject
for study and if in the fullness of time these studies
conclude there to be no taxonomic relevance then fine. Our
appreciation and knowledge of P.g. can only be enhanced even
if it is to be a simple line like 'in the Burren of South
West Eire pure white flowered P.g. may be found' in some
future revised monograph. What has concerned me is the 'knee
jerk' reaction that naming plants on flower colour is
incorrect in the opinion of some without always considering
all the details and relevant information in the paper first.
>You can certainly examine the ultrastructure or the
>chemical compounds present in a photograph, but I predict
>the results to differ significantly from those obtained
>with dried specimens.
And probably differences between different film brands,
slides, prints etc. Is there really no alternative to
removing living specimens? As a compromise could Nelson have
preserved (and sacrificed) a single flower without
condemning the whole plant - or would this approach be
considered rather too eccentric also.
>I would not recommend this kind of innovation for future
>taxonomic work. It prevents the application of other
>innovative methods.
Presumably methods which require preserved (dead) plant
material, I would be interested if you could elaborate on
these innovative techniques. I accept that photographs have
limitations, but realistically what do you do when faced
with a relatively small population? So when someone finds
Pauls suggested elusive pale flowered (and unique)
S.purpurea does the finder squash it for posterity's sake?
Or do they recognise the horticultural value, decide the
taxonomists will (for the most part) dismiss it as a mutant
and out comes the pot and spade and hay presto the plants in
cultivation - and protected by the finder by some form of
copyright providing exclusivity in the CP market place.
>RE: f. chionopetra and conservation
>My personal impression is that anthocyanin-negative mutants
>are far more likely to be pollinated, propagated, and
>preserved by some weird humans commonly called cp growers
>than by an (at the moment purely hypothetical) insect
>exclusively visiting white flowers. Therefore, the best
>measure to protect the mutant would have been to establish
>it in cultivation and to select the plant as a cultivar.
You are absolutely right - these discussions were initiated
as a result of interest in whether this plant is in
cultivation. There would be a market for this cultival and
others I suspect though I also have sympathy with John
(Wildens) comments about the Sarracenia anyplace scenario
(BAMR's Clods syndrome I believe). Here the last thing which
is desired is a cv, the most marketable commodity in a plant
is the location details. BTW John didn't we do a swap
several years ago? If so I would love to hear if you had
long term success with the P.leptoceras. I do not grow
F.chinopetra - a pale flowered P.g. I had on display at Stan
Lampards open day was P.g.ssp rosea.
>If the Burren is threatened (is it?) in its being a _P.
>grandiflora_ biotope, naming a mutant as a taxon of
>disputable value will not help much.
I am not aware of any current direct threat to the Burren. I
will be in Eire in a few weeks time, my main centre of
operation outside of Dublin will be Tralee so I may be able
to visit the Burren whilst I am out there. However given the
time of year I guess the only white thing I am likely to get
a real close look at will be the head on a pint of
Guinness!
Regarding the P.hirtiflora f. pallida ( incorporated within
P.crystallina ssp hirtiflora), a chum of mine sent me a post
card from Greece recently. He has observed a few white
flowered plants at Mt Smolikas - these individuals were
always found in the most heavily shaded locations - possibly
the colour of these plants (or the lack of it) is due to
low light intensity?
Kindest regards
Loyd
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