State of the Art and Challenges of Post-harvest Disease Management in Apples

Abstract

Despite modern storage facilities, losses from 5 to 25% of apples are still being recorded in storage room. Fungal pathogens such as Botrytis cinerea, Penicillium expansum and Gloeosporides group are mainly responsible of important economical losses even if physiological disorders (bitter pit, water core and storage scald) cannot be neglected. Post-harvest disease control is a complex problem which cannot be solved by a single solution. The control of factors affecting the fruit physiology with pre- and post-harvest handling practices, the sanitation and the application of synthetic fungicides in pre- and post-harvest treatments are the primary means of controlling post-harvest diseases. However, the future use of fungicides is uncertain due to the development of pathogen resistance, the consumer reluctance to chemical residues in food and environment and the consequent growing scarcity of fungicides aimed at post-harvest situations. Several novel approaches (including biological control agents, natural biocides and induction of fruit defence mechanisms) are emerging as possible alternatives to synthetic fungicides. However, the complete replacement of the chemical pesticides by one of these alternative methods is unrealistic because of their lack of efficacy in case of high disease pressure. These alternative methods must be integrated in association with limited quantities of fungicides, as well as efficient management and handling practices to combat diseases in harvested apples. This novel IPM approach should be completed by further studies on predictive models of post harvest disease development and genetic resistance.