The use of diphenylamine and other chemicals to control superficial scald of apples

Abstract

Summary Dips of diphenylamine 1,000 p.p.m. in aqueous alcoholic solution controlled superficial scald on 11 varieties of apples, but not on Statesman. A similar formulation applied as a spray to fruit in cases was equally successful, but some damage occurred to the bottom fruit where drainage was incomplete. Paper wraps containing DPA completely controlled scald in Granny Smith apples. Oiled wraps did not give adequate control of scald in immature, early pieked fruit. Phenothiazine 1,000 and 2,000 p.p.m. did not control scald and caused damage to some varieties. Several other unsuccessful materials are noted. Diphenylamine does not aggravate other storage disorders, and there is some evidence that it may reduce both internal breakdown and core flush.