I was thinking of trying again regalia biofungicide for mango mbbs with copper, maybe on soursop?Their is a lot of biofungicides on the market ,but hard data on efficacy has been sketchy on vegetables ,let alone tropical fruit ,even less controlled studies.
Some wall street ex fund manger stopped here a few times the last few months wants to grow a lot of soursops here.I told him it would be quite a challenge for many reasons.Turn out he had grown them commercially in panama.Told me they sprayed with bordeaux mixture for anthracnose.