Breeding low-chill blueberries and peaches for subtropical areas

Breeding to adapt temperate-zone fruit to subtropical production areas has been a formidable objective because so many different characteristics have to be changed, most of which are controlled by many genes. Recurrent selection is the only breeding method that can accomplish the required wholesale reorganization of the physiology of the plant. The principles of recurrent selection, developed and tested using short-generation organisms like fruit flies, rats, and maize, have been applied to the development of low-chill highbush blueberry (V corymbosum L.) and peach [Prunus persica (L.) Batsch.] cultivars for northern and central Florida. These principles include using many parents per generation of crosses, minimizing the time between cycles of selection, and selecting simultaneously for all heritable traits that are important in the final product, with traits of highest economic importance and highest heritability being given the highest weight in selecting parents. Many characteristics changed during the breeding of low-latitude peach and highbush blueberry cultivars, including chill requirement, photoperiod response, resistance to various disease and insect pests, fruit chemistry, and growth patterns during a long growing season.