if those were my plants i wouldnt worry about it too much. if its gonna put your mind at ease give them a check up, look under the leaves and stuff but it looks fine.
Not going to worry aboutit. Does not look to be spreading. I'm thinking it's a water issue. I was trying to dry them out a bit after a BIG rain. Then I let the top 2 or 3 inches of dirt get dry.
Looks like a little too much N in her feed. Back off it for a week and then start her back on a light diet.
Nothing major just cut back a bit
Happy growing.