Green-podding Nepenthes & Sterilization Procedures

Rick Walker (
Sat, 19 Nov 1994 15:27:48 -0800

> On the in vitro thread: although it's pretty common with
> orchids, I've yet to see green pod seed sowing done with CP's,
> possibly due to the size difference, maybe not...

Yes. I have done it with _Nepenthes macfarlanei_ pods. My protocol
was 5 minutes of isopropol alcohol, 5 minutes of 10% Clorox bleach with
a photo-flo wetting agent, and a rinse in 3% hydrogen peroxide. No
multi-stage peeling was done. I just split the sterilized pod, tweezed
out the seeds and sowed on 1/2 strength MS media. I had two infected
flasks out of a total of 8. This could be attributed to my transfer
chamber which is simply an aquarium turned on its side with a plastic
sheet over the open end.

> I'd just take a few canning jars full of soil, and drop them into a
> pressure cooker at 15 psi, and (someone help me here) half an hour?
> Hmmm....

I definitely recommend using a pressure cooker rather than baking,
microwaving, or bleaching. You can also use a sterile media like
perlite or vermiculite with a nutrient solution such as 1/4-strength
Miracid fertilizer. This usually works best for me for preventing rot,
instead of trying to use a peat-based mix.

For agar-based in-vitro media, I use 20-30 minutes of pressure cooking
at 15 psi (20-minutes for small babyfood jars, 30 minutes for big jars,
or multiple layers of jars).