Cherry breeding in the world: current analysis and future perspectives

Modern cherry breeding is relatively recent, as compared to other major crops. Nevertheless, in the last 30 years, numerous cultivars have been released, which has contributed to a significant increase in cherry production. The most important public breeding programs launched during the XXth century remain still active and new programs emerge in countries such as Chile, China or Spain. More recently, private actors are playing an increasingly important role, in particular those located in California, which conduct breeding preferentially for early-maturing and low-chilling cultivars. Nevertheless, cherry production faces significant threats, either related to the consequences of the global climate change (and in particular to the global warming) or to the emergence of new pest and diseases (such as for example the fly Drosophila suzukii). Hence, breeder have to incorporate new traits into their selection schemes, on top of the traditional and unavoidable ones, such as productivity, fruit size and firmness, tasting quality, etc. However, because of specific characteristics and of the length of the juvenility period, breeding has been traditionally limited to a rather narrow genetic base. Thus, it might not be straightforward to find interesting alleles in the breeder’ portfolios for traits of adaptability to biotic and abiotic stresses. For this reason, the preservation and characterization of germplasm resources should be considered as an urgent priority. With the recent technological developments in the area of molecular biology and bioinformatics, the use of DNA-based information, through molecular marker-assisted selection approaches, has become a reality for cherry breeder. Although important research efforts are still needed in order to disentangle the genetic determinism of the main traits of agronomic interest, these methodologies allow already significant reductions in the breeding costs. In this paper, the major goals and methodologies currently considered by sweet cherry breeder will be reviewed, and perspectives with regards to new directions and needs will be briefly developed.