Last year i had a lot of success with my fungus susceptible plants by using a system fungicide. Even my blighted quince trees seem to be making a comeback. Btw Karps sweet is not that sweet but it does resist pine rust. My plan is to proactively douse the quinces, apples, pears and the mangos and probably the persimmons too. I had some kinda nasty on my sugar apples but neem knocked it out.