Re: Hybrids

Barry Meyers-Rice (dunwich%SOLPL@as.arizona.edu)
Thu, 6 Dec 90 18:43:24 mst

Paul writes:
>probably tend to make it slower growing too. You could try a little heat
>treatment to try and trigger the seeds to germinate - 25 to 30 celsius should
>be close to what they would experience in the wild.

I never thought of specifically doing a warm (or heat) treatment on
cold growing plants, although I naturally do that during the summer
months when they are in the toasty greenhouse.

>there are examples of genera being distinguished on lesser details than this.

Oh, let me correct something. There is a third type of Utric with
four calyx lobes, and this is sort of interesting. It has four
calyx lobes, two of which are reduced in size. Secondly, the traps
on this plant are somewhat intermediate between the Polypompholyx and
"normal" Utricularia type subgenera. Sort of a "missing link" but not
missing! This plant, U. westonii, is the only plant in its subgenera.

>flowers here, I had passed them off as "duds". Is cleistogamy a
>genetic trait or is it environmental?

I don't know any more than I've already speculated. I will add one
more bit, though. Usually my chasmogamous inflorescences are many
flowered, are long (up to about 30cm), and tend to flop over after
the first 15 cm or so. My cleistogamous inflorescences have fewer
flowers (one to about 7), and are short (about 5cm) and erect. The
pot of plants that I sowed from seeds from cleistogamous seeds
produced cleist and then chasmo inflorescences, but the chasmo infl.
were short, erect, and few flowered. Sort of an intermediate case.

By petiolaris complex, I mean petiolaris, dilato-petiolaris, falconeri,
and various forms of the above. He sells em in bunches of four. So
that price gives you four plants (all the same species :-(). In the past
I've gone in with Mike, and we've taken two plants each.

>The most likely reason why some genera of orchids can be hybridized
>with other genera is that they are very close genetically, but LOOK
>different enough to

Now, Mike might blow me out of the water on this one, but let's
suppose that in filling ecological niches, it is important for a
species to avoid hybridizing with other species (plausibility
argument: species that are more likely to remain "pure" are less
likely to blend into oblivion wi/other species). We all know that
Sarracenia can hybridize, but that there may be leaky methods to
avoid this as much as possible....i.e. different flower size, colour,
fragrance, flowering times can all attract different pollinators. Throw
in different ranges for each plant and voila! Different species.
Now, if Orchids of different genera have different ranges or are
VERY selective in terms of their pollinators (which they most certainly
are), perhaps it is unnecessary for them to be unable to cross pollinate
because the possibility for that is neatly blocked by these other
factors. I know that this is a hopelessly anthropomorphic
perspective, but one which intrigues me.

Silly Idea: The biological niche which has not been filled. Imagine
a plant which genetically is almost a clean slate, with all recessive
traits. Now, this plant could hybridize with anything, obtain those
characteristics, and then colonize the new ecological niche. Now, it
would need a mechanism in which it could maintain it's own genetic
identity, but that is an exercise left to the reader.

>Are there any Utric. X Utric. hybrids

Not verified, although some are suspected. Given that some Pings can,
I bet it could be done.

>The latest Victorian CP Society newsletter mentions a possible new CP,
>Martynia fragrans. "This shrubby stands perhaps 50cm high, has
>wavy-edged

This is interesting. I know that Martynia lutea is suspected of being
a CP, and that other species are also suspected. There are three
genera of plants, Martynia, Proboscidea, and Ibiscella, which I think
may eventually be combined into one genus. I have grown Proboscidea
parviflora, and can attest to its sticky midge catching leaves. I
was not convinced that this plant was a CP---the dead midges did not
get the steamrolled look that you see with bugs eaten by Pings. They
just looked stuck and dead. Two (possibly more?) spp. of Proboscidea
are weeds in the Tucson area, and are even grown by some Native
Americans as a food crop. Also, Martynia/Ibiscella/Proboscidea lutea
is NOT native to this part of the world, regardless of what you have
read (or as erroneously mentioned in the egotistical THE CARNIVOROUS
PLANTS by Juniper, Robins, and Joel). It is an introduced WEED from
South America.

>I noticed on your plant lists Catopsis berteroniana ... What is it?

You should join ICPS. In CPN we have been told that there are two,
possibly three CP bromeliads. One, Catopsis berteroniana, is an
epiphyte native to Florida, USA. It catches bugs in the slippery nooks
of its leaves. The other one(s?) is Brocchinea reducta (and possibly
B. tatei). These catch bugs in the center well of the plant. I'm
not sure that I spelled the genus right... They are native to S.
America, on and around the Tepuis.

>Some other interesting Aussie plants are the Greenhood orchids (Pterostylis).
>These are terrestrial orchids that flower in late Winter-Spring, dying back

>Plants are probably difficult or impossible to obtain overseas (they're
>aren't showy enough for most orchid enthusiasts), but probably could be
>obtained here as dormant tubers.

Allen Lowrie used to sell these. I'm not too interested yet. I have
my arms full wi/CPs!
************************

Mike writes:

>variability in Drosera X lake Badgerup
> You can expect more variablity out
>of a hybrid. ESPECIALLY if you grow em from selfed seed (Barry, recall the
>D. X californica conversation we had a long time ago). Gemmae is a differ-

Really? Does this apply to a population of genetically identical plants?
I could see the case for variation in the F1 population from plant to
plant, but all from the same plant (barring mutations in gemmae
production)?
I have never gotten any seed from my Badgerups. In fact, pygmaea
is the only one I've gotten to germinate from seed, although I've had
plenty of seed production from pulchella. I doubt you can self Badgerup.

****************************

News from my Greenhouse:

My D. erythrorhiza erythrorhiza (my only tuberous D) is colouring
up very nicely. It hasn't caught any bugs, so I think that I'm going
to start feeding it some so that it has a nice full tuber! My plant is
about 1" in diameter.
My B. gigantea plants (5) and my D. regia (1) seedligs continue
to enlarge. My babies.
I am pleased to see that the alleged "U. reticulata" is forming
an inflorescence. If it flowers successfully I can play with TAYLOR
a bit.
I have some U. striata (aquatic) growing well. Mike grows it as
a free floating aquatic, and I'm growing mine in a submerged pot. It is
interesting that Mike's plants mostly have one type of submerged
stem, that is, with scattered bladders. My plants are more dimorphic.
I have branches completely devoid of bladders, and other branches with
only bladders and no leaves. What is more, the bladderless branches
reach up to the water surface, while the bladdery branches curve back
down (or are horizontal at most), presumably looking for more substrate.
I am convinced that this plant wants substrate in which to grow, and
to prove my point, will make a gentlemen's wager!!!
Even though Mike is better at growing aquatics than I, I bet that
my plants will flower within 8 months, and that Mike's will not!
Mind you, Mike's biomass of this species is about 10X mine! Am I
cocky, or what?! :-) :-) Care to take me up on it, Mike?

Mike, you were wondering about how humid CPs like it? Well, in my
greenhouse at night the humidity is in the 70---80% range, but (if
I trust my hygrometer) during the day it is only 28%!!! I am sort of
amazed, and wouldn't think that my plants would make it there, but I
consider the length of my plant list proof. Of course, Nepenthes are
not in my G-house.