Oh dear, that looks a bit messy. Anything on the backs of the leaves? Any ants?
I always look for mites or scale first. Little beggars spread a lot of woes around, so even if you lose the infected plant, at least the bugs won't get around. My next attempt on that one would be a dunk in BanRot. I think it's the one that combines ThioMyl and Truban which gives you a broad-spectrum fungicide.
My next-door mentor on pesticides says he would never spray Daconil on anything - which really surprised me. His exact words when I asked him about it were "Yeah, Daconil will kill everything, including you." Now, this guy has a Masters in Hort from UF, was a County Extension agent for 9 years, and more recently worked as a Pesticide Inspector for the state for several years.
