spongeofore
it finally happened… a bizarre black contaminant made its stinky way into my production line.
See the thread-like lines with balls at the end?
It’s Friday evening. I’m doing my routine incubation check and find this… scary contaminant… growing on a couple different masters mix oyster bags. From the macro, they appeared to be long thread/tubule-like structures with a black ball at the end.
me being me, I took a sample to the scope
I mean… these microstructures are really interesting (and disturbing). Is the mycelium being attacked by black bacteria? Am I the only one who’s faced this? How do I even begin my search on this?
Desperately curious, I turned to a forum that night for a back-of-the-envelope-answer. Explaining my process—that I pressure cook for the usual 2 hours, etc but noted I am using new (mesquite) pellets and suspect I may need to go longer. It could also be my sealing method, admittedly it was a little sloppy in this batch. I don’t suspect it was an oxygen issue— after all, you shouldn’t over circulate during incubation. I lean towards the first because this happened across multiple species, same substrate. Another factor is I have never seen this contaminant before— the only thing I changed was pellets, thus I think these were introduced from the new substrate stock. believe this to be an artifact of the pellets since this is in two separate oyster strains I'm working with.
After linking the video and photos, a fellow user was kind enough to inform me these microstructures are the sporangiospores of some zygomycete. After further independent research, I found out those tiny black balls from the large one are spores that are released by the sporangiophore, through the tube and this is how they asexually reproduce.
Sad for my babies who got infected— we had to let go of a few bags we were really looking forward to seeing. Since I suspect the pellets, I will pressure cook for 3 hours and obviously comed own hard on our sterile technique to ensure no human error. Honestly, I was suspicious of Mesquite but we did have a lot more success than failure — better luck next time to these strains <3 I learned from you.
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