The only fungicide I use is Horsetail tea made from Equisetum arvense. Works especially well on Beans.
https://en.wikipedia.org/wiki/Equisetum_arvense
If you are interested, I'd be happy to explain how to make a concentrated tea and how to use it. Claud
Rattlesnake Pole Beans Grown in Sand - No Commericial Fertilizers - No Animal Manures - No insecticides - No Commercial Fungicides - No Herbicides - No irrigation