Effects and Possible Mechanism of Pre-storage Heat Treatment on the Blue Mold in 'Gala' and 'Red Fuji' Apple Fruits

摘要

Hot air treatment at 38°C for 4 days was tested as pre-storage heat treatment method to control blue mold in 'Gala' and 'Red Fuji' apples. Results revealed that no decay can be observed in apples that inoculated with Penicillium expansum before treatment However, heat treatment could not completely kill P. expansum spores either in vitro or in vivo experiment Artificial wounds healed at 20°C or 38°C for 4 days before inoculation could increase the disease resistance compared to fresh infected wounds. The possible mechanism of heat treatment completely controlling blue mold is because of reduced fungal population and increased wounds resistance towards pathogen. Compared with healing at 20°C, heating at 38°C accelerated the wound healing by significant enhanced phenolic compound and lignin around the wounds in 'Red Fuji' apples. For 'Gala' apples, heating significantly reduced these materials and retarded the wound healing.