ABSTRACT
This chapter covers a wide range of issues pertaining to the many aspects of fruit and vegetable tissue physiology and changes that occur during postharvest handling and storage. Understanding the specic ethylene biology, respiration behavior, and developmental or maturity stage at harvest can provide great insight to postharvest quality retention characteristics of a fruit or vegetable. Ethylene itself is one of the most important factors determining quality retention, with different fruit and vegetable classes having differing production rates and sensitivity to the levels of ethylene present. Numerous disorders and quality defects can be attributed to exposures to ethylene in postharvest systems, and these are discussed. Respiration behaviors can be separated into two classes: (1) climacteric and (2) nonclimacteric. The classication of respiratory behavior will have an impact on postharvest approaches required for optimal handling of a particular fruit or vegetable in question. The anatomical structure and developmental maturity of a fruit or vegetable can range from an immature vegetable tissue all the way to a ripe fruit tissue, and this will also determine which postharvest procedures will be successful for handling and storage life potential. The importance of temperature, humidity, and atmosphere management on quality retention is discussed in a mechanistic manner to explain the physiological responses to these postharvest interventions. Finally, endogenous and exogenously applied phytohormones are important to signaling metabolic shifts that inuence quality retention, and these implications are explored. The discussion in this chapter is intended to provide a basic and mechanistic understanding of how and why quality changes occur in postharvest handling of fruits and vegetables that have contrasting physiological characteristics. The discussion culminates in discussion on improving quality retention of fruits and vegetables through multidisciplinary cooperation of plant breeders, physiologists, biochemists, and molecular biologists, leading to more robust solutions to postharvest problems.
