Control of Citrus Postharvest Diseases by Physical Means

Economic losses due to fungal postharvest diseases are among the most important concerns of the citrus industry worldwide. Typically, these diseases have been successfully controlled by the application of synthetic chemical fungicides. However, human health risks and environmental contamination associated with chemical residues and the proliferation of resistant strains of the pathogens are major problems associated with the continuous and widespread use of conventional postharvest fungicides. There is, therefore, an increasing need to find and implement alternatives such as physical, chemical, or biological postharvest treatments as part of integrated management programs for disease control. In this article, extensive research work based on the evaluation of physical means used alone or in combination with other control methods for citrus decay control is reviewed. Efficacy, general performance, direct and indirect modes of action, potential benefits, advantages and disadvantages, and commercial feasibility of direct antifungal physical treatments, such as heat (curing, hot water dips, and hot water rinsing and brushing) and irradiation (UV-C illumination and ionizing radiation), are discussed. The role of complementary physical means such as storage at low temperatures or in controlled atmospheres to minimize decay losses is also described. _____________________________________________________________________________________________________________