Arisaema surprise

[P.Bruggeman]

Jim,

I have to agree with you that possible hybrids can indeed complicate
Arisaema taxonomy. Unless we find a way to keep the hybrids separate from
the species we will be in for some trouble. We already have a lot of
problems identifying the new species from China so we have to make sure that
we are looking at the genuine stuff and not at possible hybrids. As more
species make their way into cultivation (and in collections) the chance that
hybrids will eventually occur increases. In a collection several species
will be cultivated in close proximity to each other and often flower at the
same time. Because most AEG-members grow their plants in the garden the
majority of seed formed at the end of the season will be of open-pollinated
origin. No one knows which crosses are possible so every seed could
potentially be a hybrid. I don't think that a Sinarisaema will cross with a
non-Sinarisaema but hybrids between ciliatum and consanguineum do occur,
both in the wild and in cultivation. I have several seedlings from ciliatum
as the mother and they lack ciliae and are non-stoloniferous. I can imagine
that crosses might occur within sections but at the same time Pradhan
reports in his book that speciosum, galeatum and intermedium grow in close
proximity to one another without producing hybrids. Nevertheless, if a
possible hybrid does make it's way into a seedex it will find it's way into
other collections and eventually into the trade and before we know it we
have to figure out what is what and don't know what we buy anymore.
Uncontrolled hybridisation already has made a mess of genera like Primula,
Androsace, Lilium etc. so if we can avoid this with Arisaema it would best
to do it while we still can. Not many known Arisaema-hybrids exist to date
but with the increasing numbers of species we now grow, more and more
hybrids will be produced. I don't think that marking donated seed als open
pollinated will be of much use for the simple fact that all the seeds of
garden origin (from a reasonable collection) COULD be a hybrid. Marking HAND
pollinated seeds as such would certainly be one of the options because you
would then have some assurance that the species comes true from seed. For
all the other seeds I hope that fellow AEG-members try to pick possible
hybrids out of the resulting seedlings as soon as possible and label them as
such. I myself am a species-purist so I already do that but even if you
don't mind growing hybrids I still hope that people will try to keep the
hybrids separate from the species for growers like me. Has any one has
another sollution for this problem? I am aware that there will always be
growers who like to improve on nature and as long as the resulting hybrids
are named and recognisable there is no problem. Knowing who the parents are
of a cross would then be an added bonus. Registering hybrids makes sure that
everybody has the choice whether or not he or she wants to grow hybrids.
Allowing species and hybrids to mix not only makes it hard for growers like
me to buy plants at a nursery but can also create new problems in
identifying species. Questions like "is this plant a variety of species X or
is this a cross between species X and Y and is species X not as variable as
we thought?" can then be avoided. Any other suggestions?

Pascal




-----Oorspronkelijk bericht-----
Van: Arisaema Enthusiast Group (AEG) Discussion List (and other hardy
Aroids) [mailto:ARISAEMA-L at NIC.SURFNET.NL]Namens Jim McClements, Dover,
DE z6
Verzonden: donderdag 3 augustus 2000 17:22
Aan: ARISAEMA-L at NIC.SURFNET.NL
Onderwerp: Arisaema surprise


One of the most enjoyable things that can happen to a seedaholic is to have
something unexpected come from seed. Of course, it's only enjoyable if the
unexpected isn't a weed!

In '98 I planted seed from A. angustatum peninsulae variegata DJH183 that I
had had in the garden since '96. I remember thinking at the time that it was
odd that it made seed, since it was the only one I had, but assumed that
there may have been some male flowers present. The seed were germinated and
raised under lights, with the usual three months in the refrigerator between
growth cycles. They came out of their second refrigeration last month and
were large enough to plant out in a bed.

Yesterday I found that 4 are flowering, almost identical, with a perfectly
white globular appendix, obviously the result of pollination of the "mother"
by A. sikokianum. (which were growing nearby). This is a striking hybrid,
even more attractive than the sikokianum/takedae hybrid that Don Jacobs
produced a few years ago.

However, it points out a fact that we sometime tend to ignore. Now that many
of us are growing many newly-available species of arisaemas, the term
"open-pollinated" will become much more significant. Seed from a given
species, unless it is completely isolated from other pollen, has a good
chance of being a hybrid. In the wild this can certainly occur if two
species
grow in proximity, but most often such is not the case. It's also obvious
that pollination/hybridization can occur without human help!

It might be well for the seedX to ask donors to identify seeds that are
"O.P". Arisaema taxonomy is confused enough without having a lot of garden
hybrids introduced into the mix.

Jim McClements