Postharvest treatment with thiabendazole (TBZ) or benomyl reduced the incidence of soft rot or blue mold disease caused by Penicillium expansum Thorn in ‘Mcintosh’ apple fruits. Both materials were significantly effective during cold storage or simulated marketing tests in which the apples were artificially punctured and then dipped in solutions containing rot inoculum and the chemical. All concentrations tested, 250, 500 and 1000 ppm TBZ and 75, 140, and 300 ppm benomyl, yielded rot control without affecting the respiratory activity of the apples.
Received for publication December 22, 1969. Michigan Agriculture Experiment Station Journal Article No. 4941.