LC to agar first or straight to grain jar?

Greetings,

I will be purchasing a syringe of liquid culture (LC) that is supposed to be sterile, should I expose it to sequential agar plates to isolate a strain or inject the LC straight into my prepared grain jar?

Thank you, Sir-Shrooms-a-lot

Hello,

In an ideal world, Liquid Culture (LC) should be made from a clean isolated culture. In reality? (I mean shop-bought cultures)... Who knows!?

The best practice (recommended, but not required, especially for beginners) is to check any new culture on agar to be sure if it's 100% contam-free. However, if you're not experienced with agar, better to skip this step, as it can lead to false positives. In that case, go straight to grain!

The pattern of mycelium growth on agar will also indicate whether it's an isolated culture or a multispore culture.

Even, snowflake-like, rope-like growth is an example of an isolated culture (see photos):

Different patterns of growth, both fluffy and rope-like growth, borders between different types of growth within one plate is a multispore culture (see photos):

All the best, Shroomok

Thank you! That was a great answer, with pictures too! I do have some experience with agar, so I think I am going to check out the LC on a plate first. I have a laminar flow hood, and I do my sterile business in a large tent and in front of the hood. I am a nurse so I am meticulous about my sterile technique! I shouldn't get a false positive, but it is always possible. If it fails, and I cannot isolate a strain from contamination then I will just put it to grain and go from there. I will post images as I go along. Thank you kindly for the supurb answer and your wisdom. More to come.

I'm so excited to see your results on agar! 🤞

It's great you're already experienced with agar, have a deep understanding of what a "sterile technique" means from another field and all necessary equipment. Superb!

Feel free to ask if you have any questions along the way or just share your insights with others here on the forum. I appreciate it!

Best of luck :-)