let me introduce some experimentations i follow with naive terrestrial orchids and local soil / fungus.
(https://i64.servimg.com/u/f64/18/58/12/07/germin10.jpg) (https://servimg.com/view/18581207/742)
all the species i have sowed by this way show after a few weeks inflated nuclei and i have good hope that a fungus is not stranger to this step.
when the seeds will have formed leaves, i think i could try to put some onto malt agar media and "harvest" in a first time some fungus, and in a second time isolate interesting strains.
Lazzaret, how did You isolate the fungi and where did You found them?
i haven't isolated any fungus yet. I only see under microscope that fungus are present and that the seed are inflated, and the integument broken (in some case), as this one with dactylorhiza maculata.
the seed with its typical mycelia connected
(https://i64.servimg.com/u/f64/18/58/12/07/macula10.jpg) (https://servimg.com/view/18581207/744)
to find fungus in the soil is easy. I used local soil of the meadow behind the house. It's not a referenced strain, so i can't say if it is B1 or another one.
to isolate the fungus, i let them grow untill there are leaves, i choose a young plant et i replate it on malt agar media. I let the fungus grow and i will isolate by selection a new fungus