In his study of the preharvest use of 1-MCP (methylcyclopropene) on apples, Dr. Jim Schupp observed some phytotoxic issues in Golden Delicious that “caused us a great deal of concern.” The University of Pennsylvania horticulturist said that he had never before had any phytotoxicity problems with MCP, so the phytotoxicity issues were alarming. Most of the fruit cracking injury was found from dilute applications using the handgun and air blast sprayer, he explained. Further study showed the phytotoxicity was related to the interaction of MCP and the application of captan/oil made for summer disease control. “It was not anything to […]