Reduction of green mold on grapefruit after hot forced-air quarantine treatment

Lesions on grapefruit developing from wounds inoculated with a spore suspension of Penicillium digitatum just prior to heating for 300 min in 46 degrees C moist, forced air developed less rapidly during 4 days of storage at 21 degrees C than lesions formed from inoculations made after the fruit were heated or lesions on non-heated fruit. Since the lesion size on fruit inoculated after heating was similar to that on fruit that were not heated, induced host resistance via lignification or accumulation of phytoalexins probably did not occur. Results from this research demonstrate that development of green mold on grapefruit caused by P. digitatum is inhibited by time and temperature regimes of moist, forced air that are known to provide quarantine security against Mexican fruit fly.