Physical and Chemical Control of Postharvest Diseases

Microbial decay is a major factor responsible for postharvest losses and compromises to the quality of fresh produce. In the past, the use of new fungicides has extended the shelf-life of fresh fruits by reducing losses, but in the last two or three decades, concerns about public health and the environment has considerably limited their use after harvest. Future scenarios are tending increasingly more towards integrated crop management and organic fruit production, with a consequent reduced use of fungicides, for a sustainable agriculture system. This goal requires new technologies to control postharvest disease. Intense research in the last 30 years has produced numerous studies that show significant progress in the reduction of pesticide use for disease control, although some critical points have still to be considered. It is unrealistic to assume that the physical and chemical methods described above have the same fungicidal activity as pesticides, and an integrated approach appears the best method to obtain acceptable results. However, further research is needed to investigate the activity of GRAS compounds, natural compounds and VOCs, in large-scale experiments, their mode of action and their degradation in organisms that are still not fully understood. Physical methods probably have a better chance of prompt application on a commercial scale since some of these, like heat, do not require any registration. Nevertheless, also in this case, more investigations have to provide additional information on appearance, texture, flavors, and storability of treated fruit. Finally, research should lead to the development of appropriate tools to tailor a complete integrated disease management strategy specific for each situation that takes into account factors such as species, climate and seasonal conditions, and the market destination.