Re: shrubbies

Paul Taylor [Falcon] (s882080@minyos.xx.rmit.OZ.AU)
Fri, 7 Dec 90 21:36:22 +1100

>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.

That's what I had in mind (original note was a bit vague). I can't think of
anything special I did to get them to germinate, although the pots might have
been left unwatered a couple of times...

>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.

A "missing" hybrid perhaps?

>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.

Your second point (selective pollinators) is correct in general. In
fact, many orchids are so specific as to the insect that pollenates them
that the extinction of that insect will cause them to also become
extinct. As you say, this ensures that the species will only fertilize
plants of the same species (unless an orchid grower gets in first!), but
is a pretty risky system.

>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.

An alternative to carnivorous use of the sticky dew is to trap any pests
(e.g. aphids) that might try to feed on the plant. Drosera etc. may
have had ancestors that used such a system, then developed a means of
using the traps insects for its own benefit. According to Robert Gassin
of the VCPS, trials where Drosera have been excluded from external
sources of bacteria seemed to get very little benefit from trapped
insects. It seems that air-borne bacteria are
the source of enzymes in the mucilage, but it is not known if the
bacteria get anything from the relationship.

>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.

I've heard of Brocchinia reducta, but not the others. I saw a program
about some crazy parachutists that landed on top of one of the Tepuis
(and were going to jump off again), which showed great stands of
Brocchinia, along with the Utricularia (by colour, I would guess U.
quelchii, but U. nelumbifolia and U. humboldtii are known to live in
Brocchinia also) that lives in them. The flowers on them were HUGE.

>News from my Greenhouse:
>
> My B. gigantea plants (5) and my D. regia (1) seedligs continue
>to enlarge. My babies.

Slime "ate" my D. regia seedling (sounds like a B-grade Sci Fi movie :-)

A new addition to my glasshouse is a Drosera adelae. It wasn't very sticky
when I bought it, but looked healthy, and had several side shoots and is in
flower. After being put inside the fish tank INSIDE the glasshouse with my
two Nepenthes, it is looking very happy. There is about 2" of water
underneath, but not touching, the pots which keeps the Nepenthes happy all
year without heating. They aren't very big, but are getting slightly bigger
each year, which is a good sign.