Phytophthora Root and Stem Rot of Apple Rootstocks from Stool Beds

(...)Field applications of fosetyl-Al and metalaxyl to apple rootstocks reduced disease severity in the field, reduced lesions on excised stem pieces inoculated with P. cactorum and reduced disease development on apparently healthy rootstocks while in cold storage for 3-9 mo. Short-duration root dipping of healthy or mildly infected rootstocks before cold storage in high concentrations of benalaxyl, etridiazol, fosetyl-Al, or metalaxyl reduced disease, but the degree of reduction varied. Fosetyl-Al and metalaxyl consistently produced the best results. None of the materials were phytotoxic