Are you sure it's not just what's left of the cotyledons?
I was wondering if others had this on the stems. It is only on certain strains and just want to make sure it is not a fungus or desease. Anyone else have this stuff on the stem of certain strains?my plants stem is like that, its fine
Have Actinavate and will give that a go but will probably pick up Serenade as a second treatment option. If it is some type of epidermal fungus wonder if anyone else has a thread on this attacking plants.Actually after looking for a bit longer my professional guess is it is some sort of epidermal fungus. Try spraying with Serenade.