Re: What is a carnivorous plant?

Peter Cole (carnivor@bunyip.demon.co.uk)
Fri, 17 Jun 1994 16:58:54 GMT

Steven Klitzing writes:

> What about the world's largest flower, Rafflesia, which grows in the same
> jungles as Nepenthes? It's a parasite that grows on a vine. That isn't
> exactly carnivorous, but it's not symbiotic either.

I believe it does trap insects. But only for pollination, and
then it lets them go again. The David Attenborough documentary
series _The Private Life of Plants_ shown on UK TV earlier this
year had the most spectacular time-lapse photography of a Rafflesia
flower opening, and from inside, of the pollination process.
If it ever turns up on US TV, Don't miss it! Plenty of CPs
in the series as well :)

> I would like to see
> somebody breed, via genetic engineering, a temperate Nepenthes plant that
> you can grow outside in your garden. The only problem is, if you live
> in an area with cold winters, the water in the Nepenthes pitchers would
> turn to ice and explode the plant. So, this Nepenthes would have to
> be capable of producing anti-freeze in its system as well. Perhaps it
> ferments bacteria into alcohol and mixes the alcohol with the water
> inside it. Or, maybe engineer a CP with its own chemical heating like a
> firefly, or grows a fur coat like some succulents and cacti to protect
> it from cold.

Well, my purpureas freeze in the winter, but the pitchers don't die
immediately, and my Darlingtonias must likewise freeze solid, but
they hardly die back at all until new growth starts in the Spring.
The size of a Nepenthes pitcher might prove a problem - the extra
volume of a decent sized one (and if you're going to genetically
engineer it, you might as well increase the trap size just for fun,)
would expand considerably. Unless you bred it into an obconical
trap shape (like a Sarracenia,) the constriction of the neck, being
narrower than the body of the trap, would, as you say, cause
problems.

My solution to this would be simple (!?) :^) - an expandable,
concertina-style neck to the trap, capable of opening to a
diameter greater than that of the body of the trap in response
to the upwards pressure of ice. If the genetic components
governing this were assembled from those responsible for Dionaea's
trapping, the mouth could also be triggered suddenly by
approaching prey and spring from a discreet hole to a gaping maw
in a fraction of a second thus engulfing its victim. Ideally
the trap mouth should emerge at ground level to maximize the
variety of prey available.
Alternatively, a purely electrical system could be employed by
splicing in Mimosa genes instead of Dionaea - this would have the
advantage of allowing more trapping operations to occur in the
lifespan of the trap (the cellular growth mechanism of Dionaea
being an obvious limiting factor.) It might mean foregoing the
excellent double trigger phenomenon of Dionaea though, risking
the trap filling up with twigs and leaves.

Happy hypothesising,

Peter