I primarily grow Ganoderma in sculptural glazed ceramic "vessels"
Over the past year I've experimented with this process. There isn't a lot of information on ceramics+cultivation, so a lot of this is trial and error. When I can I follow standard lab procedures to a T, obsessively scrubbing my flowhood and work surfaces with hydrogen peroxide, bleach, and alcohol. My lab work got better... a number of exciting pieces were made successfully in the fall (photos on my account)
But my contamination rates are suddenly high again (98% of the time to trich). I work hard to keep everything clean sterilized.... and have low contam rates for inoculated 5lb bags, agar cultures, grains, spawn. But now I've lost months of work with some of these and I'm desperate for advice. Can anyone help me? I cleaned my pieces out and soaked them in bleach. Hopefully this forum is helpful for others too trying to understand contamination.
Here's what I think might be happening (obviously there could be a number of issues, but here are the details that seem salient):
1) filtration: In the beginning, my early experiments were successful probably because my pieces were small enough to fit inside a 5lb autoclave filter bag. I kept them in the bags until healthy pins formed. Now that I'm experimenting with larger ceramic pieces that don't fit inside autoclave bags I've resorted to putting micropore medical tape over the large openings... some of which are about 3" diameter holes. I try to keep the tape dry during sterilization with tin foil. I use two layers of tape on top of each other for extra filtration. After a number of pieces were lost to contamination, I'm starting to doubt my micropore tape. Tyvex would be better I bet, but I'm not sure how to create an air locked seal. Polyfill doesn't seem to be an option since the openings are so large. How can I create large seals for holes in the top of my ceramic pieces. Is there a product I'm missing? Some of my ceramics are smooth some have glazes that are a little bumpy. I leave the micropore tape on these pieces untouched in a dim "clean room" until pins push against the tape or I suspect contamination.
2) Ceramics themselves. Obviously it has occurred to me that my glazed ceramics might be too porous and storing/breathing contamination through the walls of my sculptures (about 1/8" of glazed ceramics typically). I find a way to get almost all of the ceramics directly into the PC or autoclave (recently gained access to one) with my supplemented sawdust already inside. I wash them with hydrogen peroxide before filling them 70-85% full with supplemented sawdust. the glazed vessels all can hold water indefinitely without leaking. I've had success with ceramic sculptures that are filled with sterilized spawn in the flowhood using a funnel, pouring from 5lb blocks of sterilized sawdust substrate. Some of these ceramic pieces didn't even go through the autoclave and were still fine. Are these just lucky flukes? Or is there another explanation as to why some colonize and others get contam?
3) My sawdust mix. I add gypsum to a masters mix of 50% soy bean hull 50% hardwood sawdust. Can I fight the trich more effectively for ganoderma with a different mix? I've never had much success with verm or lime in anything.
4) improper air exchange. I've noticed that when I pack my spawn into a long cylindrical piece using a sterilized metal plunger my mycelium grows too slowly. I wonder if this is why my spawn loses the race to contamination. I'm assuming the tighter I pack my substrate the harder it is for the mycelium to spread. Also, I'm still finding it difficult to calculate how much air my mushrooms actually need after inoculation. As an experiment I tried to inoculate and fruit a Ganoderma lucidum out of a metal tea pot spout. A small 1/2" diameter opening being the only source of oxygen (through micropore tape) This didn't work. My guess is the mushrooms aren't getting enough air when I use these small air ports. But how can I calculate my air exchange.... even when I'm making my sculptures. Can one 2" diameter opening offer enough air for inoculated 10lb sawdust. What about 1"? Where can I find more information that might help me calculate these things in the future?
I'm really excited about these experiments and would greatly appreciate any feedback. Thanks Shroomery
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