I normally stratify my seeds in coir & then plant in a very fine peat/perlite mix. Currently I’m planting sprouts from seeds that had been bagged for a year or two. I’ve noticed a fuzzy white mold looking something like candyfloss attacking the seedcoat of a sprout after it had broken the surface of the soil. (That sprout is history now.) I’m thinking its an airborne pathogen. What could it be?
I believe the mold is helping the seed coat break down, making it easier for the sprout to come out.