ABSTRACT
Fruit breeding is a long-term process, which takes a minimum of about a decade from the original cross to a finished cultivar due to two challenges: long juvenile periods and large plant size. Thus, much thought needs to go into which objectives to be emphasized in the breeding. Although certain objectives, such as yield is always important, the overall lifestyle, environmental, marketing, and production trends affects the objectives that breeders emphasize in their programs as they strive to anticipate the future needs of the fruit industry. The importance of each trend varies with the crop and environment. The major trends are to develop cultivars which simplify orchard practices, have increased resistance to biotic and abiotic stress, extend the adaptation zones of the crop, create new fruit types, create fruit cultivars with enhanced health benefits, and provide consistently high quality. In spite of these difficulties, breeding programs have been developed in all important perennial fruit crops, aimed at the improved economic profitability of the crops by increasing yields, altering the harvest window, creating new fruit types, and improving fruit quality while simplifying management. The characterization of fruit quality is always difficult and often controversial. The problem is further aggravated when considering fruits and nuts due to the complexity of their physical and chemical composition and the ongoing metabolism of these components during ripening and postharvest. Differences in consumer preferences make a universal definition of fruit quality difficult, even ephemeral (Janick, 2005). Fruit cultivars can be characterized for commercial quality, industrial quality, sensory quality, and nutritional quality. Commercial quality refers to all aspects related to the external presentation of the product, including size, shape, surface texture, color, and ultimately marketable yield. Industrial quality refers to how compatible the cultivar is with the various handling, transport, processing, and storage practices typical to its preparation for different markets. Sensory or organoleptic quality refers to those factors that determine consumer preference and thus is subjective and highly variable, while nutritional quality refers to the specific nutrients provided and the overall contribution to consumer health.
