Programmed cell death and postharvest deterioration of fresh horticultural products

Postharvest performance of fresh horticultural products is largely affected by processing and storage conditions. Various practices such as chemical and physical treatments and controlled or modified atmosphere storage can delay the senescence and reduce deterioration. However, the treatments and storage environment may also be stressful and induce detrimental physiological, metabolic and molecular changes resulting in quality loss. The macroscopic symptoms of quality decline have gotten an appropriate attention, but the processes underlying the defects at the cellular level are not well understood. It is suggested that some of the postharvest disorders may involve programmed cell death (PCD): a genetically determined process of cellular suicide indispensable for normal plant development and an important mechanism for survival in response to stressful environmental factors of biotic and abiotic origin. In this review the contribution of PCD to postharvest senescence and storagerelated deterioration of perishable horticultural products is discussed. For better comprehension of plant PCD, the major concepts are outlined. Senescence is considered as a specific form of PCD. Examples of recent and earlier findings demonstrating the incidence of storage-related PCD are presented. It is suggested that revealing the implication of PCD in postharvest disorders may trigger the development of new or optimized preservation strategies addressing cell death. Identification of PCD related markers can be a promising tool for predicting the shelf life of harvested products. The control over postharvest stress-induced PCD may be beneficial for the postharvest industry in sustaining the quality in the supply chain as well as in breeding programs for obtaining products with improved tolerance to storage-induced stress.