sterilization with UV lamp?

[Nepenthesguy]

I'm going to venture into flasking soon and was wondering if anyone has used a germicidal lamp to sterilize their media and flasks before sowing the orchid seed? Would it work or could it alter the media?? (seed would be sterilized via a chemical method and not be exposed to the UV light)

[WhiteRabbit]

[Fairorchids]

Lamp is surface treatment. You need to treat a sigbificant volume (= thick layer). Heat is the way to go.

If U do not have pressure cooker, consider baking in oven.

[Subrosa]

Originally Posted by Fairorchids

Lamp is surface treatment. You need to treat a sigbificant volume (= thick layer). Heat is the way to go.

If U do not have pressure cooker, consider baking in oven.

I don't think uv can replace heat sterilization, but in conjunction with heat it could definitely provide another level of protection against contamination. Assuming that the media is properly heat sterilized and hot enough when it goes into the flask any subsequent contamination is most likely to occur on the surface of the media during sowing. The basic premise behind uv sterilization is the old adage about the difference between medicine and poison is dosage, and the fact that different organisms require greatly varying dosages to eliminate. Molds and fungi tend to require fairly high doses compared to bacteria and viruses. The $64,000 question is what dosage is required to mess up orchid seeds. If orchid seeds can tolerate sufficiently greater uv exposure then uv could be very helpful indeed. I don't know if any work has been done on this subject.

[Nepenthesguy]

Originally Posted by Fairorchids

Lamp is surface treatment. You need to treat a sigbificant volume (= thick layer). Heat is the way to go.

If U do not have pressure cooker, consider baking in oven.

At what temp and for how long would I bake the flasks?

Originally Posted by Subrosa

I don't think uv can replace heat sterilization, but in conjunction with heat it could definitely provide another level of protection against contamination. Assuming that the media is properly heat sterilized and hot enough when it goes into the flask any subsequent contamination is most likely to occur on the surface of the media during sowing. The basic premise behind uv sterilization is the old adage about the difference between medicine and poison is dosage, and the fact that different organisms require greatly varying dosages to eliminate. Molds and fungi tend to require fairly high doses compared to bacteria and viruses. The $64,000 question is what dosage is required to mess up orchid seeds. If orchid seeds can tolerate sufficiently greater uv exposure then uv could be very helpful indeed. I don't know if any work has been done on this subject.

The times for fungal spores do very but they are recorded (had info on it before). If one of my more common plants produces seed I'll test the exposure limits, seems like it would be good info to have

[Fairorchids]

My dad used oven, but I do not recall time or temp. I am guessing at 350-400 for min 1 hour.

If you flask on kitchen counter and get minor contamination, you can burn the mold/bacteria away with sunlight + magnifying glass as a lense.