So what is wrong here? Tried germinating 5 different kinda spores and they all look like this. It started out by growing white dots - thought everythinhg was fine. Next time it was checked every white area is surroundet by green mold. Does this mean the spore solutions are contaminated? A flowhood was used, so I find that highly unlikey.
At first spores wouldn't germinate on plain agar, so they were rehydrated in syringes.
Maybe the spored are bad? Guess Its best to start over!

Did you inoculate in just one place on the dish or would all of those spots be from the spores you used ? Those look like mostly individual contamination sites as opposed to one point of contaminated mycelium spreading outward. It could be from airborne contaminants or insufficient sterilization. These definitely don't look like they all came from one spot on each dish. There could be dozens of reasons though, a little more info on your technique might help a little.

pardon me. I should have been more specific. Haven't practiced this hobby inna while..
It was incoculated once and nothing happened, so the second time sporesoluion was deposited all over the dish. Obviously something went wrong on each inoculation point. Which leads me to think it had to be the spore solution itself. But then again its highly unlikely that it happens in five different syringes. Like you say, there could be dozen of reasons. Next test will be with fresh needles and only one inoculation point.
Thank you!

Looks like your sterile procedure needs work, or your dishes weren't sterile. Are you sure your FH works properly?

Was the sporeprint made from a mushroom you picked outdoors? Green mold and other contaminants are more common on wild mushrooms.

The green in green mold are the spores, the mycelium is white, so my guess is that all you got there are green mold.

When growing on petri dishes, a good technique is to cut out small sections of good mycelium and transfer to a new petri dish and do this a few times to clean it from possible contaminants. But you need a culture from the wanted species growing from the beginning... Keep trying.

oetzi13

The reason for the different growth points is that you did the right thing = You pressed the syrynge hard enough that the solution sprayed out instead of droped out . That means that you then have clearly different growth points that you could then keep transfering untill you get a clean culture .

Why are you wasting time with petri dishes ? That went out of fashion at the latest when PF tek came out . The advance was that one cut the petri dish stage out because it was not needed by the most growers and because it was an extra step = an extra chance to get contamination .

Whatever ....... you have problems . SO ...... get yourself some spores from a reputable spore dealer and then do PF tek . Dont complicate things do one type of spores at a time .

Only use sterile syrynges and needles . That means each one once .

Make sure that your flowhood is blowing and not sucking ?

If you get contamination in any containers .......throw them away without opening them .



I used to grow with no sterility . So did a friend of mine . It worked for years with no problems . Then we got contamination . Now neither of us can grow in our apartments without sterility . If we try we get masive contamination . In my apartment its green / green blue mold and a nasty black mold = Maybe Aspergillus niger = B-A-D . Now if i dont dry the shower for a few days black mold grows in corners . My landlord freaked out and gave me some nasty chemicals to get rid of it . They work ....... for a few days .......... but they dont get rid of spores or growth that one cant see .



If you give some more details it would maybe help people to help you . For instance ...... Where did you get the spores from ?

My FH works probably as it is brand-new. The prints were all from reputable sellers, albeit some of them are like 12 years old. I don’t know if that matters. Yes, the idea was to transfer some good sections. There just wasn’t one!
I had no idea petri dishes are out of style. How else does one get a pure culture? Many years ago I used the PF tek. I just wanted to step up my game this time.
Imma gonna try using fresh needles instead of sterilizing them and see how that turns out.
If that fails it’s got to be the spores themselves..!

thank you all!

Petri dishes are great man, for modern growing setups. PF is really for beginners, if you've got a flow hood then I assume you're past that level. Agar to grain jars to coir/verm monotubs is what I'd consider the modern edge of home growing and much more effective and efficient than PF, and there are other more innovative methods being developed everyday too.

If you've been out of the hobby for awhile and want to get caught up here's where I'd recommend you start reading: Franks teks

Try opening a clean dish in your flow hood and see what you get without any innoculation. Also maybe open one in the room without using the hood for comparison purposes.

If your sterile procedure is good, then you may be fighting contams on your prints, or your rehydration process. Probably worth re-investing in some fresh spores, or you can just keep scraping those to agar, you should get something eventually.

good luck!

oetzi13

There are only two posibilitys = The spores are contaminated or you didnt get the sterilty right .

Did you open those spore prints outside of the flowhood ?

12 year old sterile spores should be OK ....... BUT ...... how long did the suplier have them before that ?


" the idea was to transfer some good sections. There just wasn’t one! "

Thats what i see from the picture . How could you clean up those cultures ? Is it posible seeing how much contamination is there ? Can you see any myceleum you want in them ?

You undestand that when you opened those contaminated petri dishes you spread " zillions " of spores in the room ? Never open contaminated cultures throw them away .

You understand that every time you cut a piece out and grow it you are introduceing an extra step that could get contaminated ? AND that untill youve done it enough times to clean it up you are also growing contamination ? How many times would one have to cut and grow those culture to get a clean one ?

Its easier , safer , quicker and cheeper to get a new clean spore print ...... unless your aim is not to grow mushrooms and you only want to play / experiment .


" I had no idea petri dishes are out of style "

Yes . Except with beginners , people who want to play / experiment and people who live on mars = they cant get a new clean spore print . OR ....... when someone finds a single mushroom and wants to grow it . Then they either go for a tisue culture or a spore culture . Can anyone think of another reason why someone would want to clean a spore print up ?


" Imma gonna try using fresh needles instead of sterilizing them "

That means that you dont sterilize the syrynges ? And it means that you have a glass and metal syrynge and needle ? Because you cant sterilize plastic needles and syrynges ......... wich are easy and cheep to get packed in a sterile pack . They get used one time and then get thrown away .

Thanks GOD, I think you nailed it! I obviously haven’t been doing this in a while cause I was under the impression that you CAN sterilize plastic syringes. No wonder it comes out that way then! Duh..
I’ll just get new prints and start over. I was very careful otherwise, thats why this surprised me.
Something had to be very wrong!
My bad..time to do some much needed reading.
Thanks for the link, SinysterKyd, that looks like a lot of fun!

oetzi13, you should definitely try to systematically analyze your sterile process like other people suggested. Read the blue Stamets book on mushroom growing, it has some nice information on sterile workflow systematics.


If petri dishes are out of style since PF tek came out, then spore prints are out of style since preinoculated grow kits that you can buy online came out.

There are many good uses for petri dishes other than cleaning up unclean prints. Selecting a good strain from a multispore inoculation is one. Cloning a mushroom fruitbody for later propagation onto grains is another.

Agreed, they are necessary for those things. The problem is people see fume hoods and petri dishes and gloveboxes when doing their initial research, and certain forums and sites are notorious for giving conflicting info. None of that stuff is needed for basic teks at all.

Anyway, they shouldn't be necessary here, from a reputable place the spores or spore solution should be sufficiently sterile to inoculate substrate straight away. Other than that it can only be a sterility issue.

Then how were they sterilised in the first place?


I've successfully steam-sterilised plastic syringes for re-use, but I wouldn't encourage it as a habit.

Usually with ethylene oxide. Gamma irradiation is also a possibility. It should say on the packaging what method was used: e.o. is ethylene oxide.


Me too. The plastic does deform a slight bit, causing the plunger to not move as easily about the place where it sat while pressure cooked.

For health and safety reasons, it is not advisable to try ethylene oxide or gamma irradiation at home.