My name is Linda and I'm not an expert but I did find an article about caring for fruit trees and how to help prevent the most common diseases for various types of fruit trees. I hope this helps you.
Hi Steven, we've used hydrogen peroxide on our cherry trees and it worked great. https://homeguides.sfgate.com/hydrogen-peroxide-treat-fungus-fruit-trees-36492.html
'Evergreen Pear' trees (non fruiting) are known to get blight easily. Be sure to keep any trimming tools very clean in between cutting branches or you can spread it.