Nepenthes and light

Michael (IFMJC@ASUVM.INRE.ASU.EDU)
Fri, 24 Sep 1993 20:49:38 -0700 (MST)

If I understand the running conversation, the theory is that (some)
Nepenthes pitcher better when grown in reduced light. Presumably the
production of more or more colorful pichers results in more insects
caught, and this "makes up" for the reduction in photosynthesis?

This doesn't seem to hold water (no pun intended :-) since the purpose of
photosynthesis is carbon fixation (CO2 --> C6H12O6). As far as I know,
photosysnthesis is the ONLY way a plant can fix carbon (well, aside from
parasitic plants, but they cheat by sucking another plant's photosynthate).
Carnivorous plants can't get C6H12O6 or other metabolic energy sources from
their prey. They can only extract minerals (fertilizer) from prey (as far as
I have been informed).

Increased photosysnthesis (more light) would give the plant more energy
source, and structural building blocks (both glucose), which means the
plant SOULD grow faster/larger, unless increased light/heat compromises
other enzyme systems, photoinhibition, and whatnot. Increased growth
SHOULD increase the need for minerals, thus more pitchers...?

Has anyone actually OBSERVED more vigorous pitchering on plants moved to
the shade? Could this be due to reduced temps or reduced transpiration
in the shady area?

-Michael