Please help. Is this the beginning of a parasite attack or could it be fertilizer sun burn ? Some leaves, not all, have brown stains on them.
http://postimg.org/image/uajpua93z/
http://postimg.org/image/krwmpkk91/
http://postimg.org/image/uajpua93z/
http://postimg.org/image/krwmpkk91/