Day 4 of growing Pleurotus ostreatus cultures from spore. Only one plate got contaminated, but it was bad. There are two contaminant fungi going to battle, and around three possible bacterial colonies. I must have been losing it at the end, haha! Can’t wait to see how they progress!

  • SalamanderM
    link
    fedilink
    32 years ago

    Side thought: a lot of people recommend the z-shape swabbing, but it seems kind-of counterproductive if you’re trying to select for the apparent speed and strength of mycelium growth.

    Thanks! Interesting to see a line like this :-)

    I like preparing a dilutions series and then preparing two or three plates per dilution by adding 1 mL of liquid into the plate. Usually one of the dilutions has a good spore density to get well-separated colonies.

    • @lightingnerdOP
      link
      22 years ago

      Oh, that’s a great idea! I’m clearly new to mycology, so I’m just kind-of experimenting–but you’re right, we’re talking billions of spores, and only two need to meet in order to form a strain. Hmm…

      • SalamanderM
        link
        fedilink
        32 years ago

        only two need to meet in order to form a strain

        Yeah! And when they do meet, they form a new anatomical structures called ‘clamp connections’, so if you have a microscope it is easy to check if the mycelium has already mated.

        There is a nice series about breeding and how to isolate single-spore haploid mycelium here: https://www.youtube.com/watch?v=vsJpjQhsDIM

        The idea is that if you manage to grow plates from single un-mated mycelium, you can then control their breeding, and this is how you can make new strains and have more control over their genetics. It is a more advanced topic in mycology, but a very interesting one to learn about!

        • @lightingnerdOP
          link
          12 years ago

          I went and skimmed through that whole series, and then I found another video where he discusses the problems of going spore to grain, and even assuming I did get some viable mycelium on these plates, I’m thinking it’s going to be nearly impossible to select them properly. I suppose I could just rinse and repeat into new plates, but then I won’t know if it’s a viable diploid/dikaryon or not.

          Yet, the video I initially watched https://www.youtube.com/watch?v=tYK0hLeanVc demonstrated just grabbing some spores with a sterile blade and wiping that across agar. So maybe it is a reasonable method? One thing’s for sure, there’s a lot of colonies along the inoculation line, and it’s already probably too late to start isolating like you would with the method demonstrated by Fresh From the Farm.