Breeding work and floral biology research in cherries at Fruit Research Institute, Cacak – achieved results and new perspectives

Abstract

Decades-long cherry breeding work at Fruit Research Institute, Čačak (FRI), implies the use as a main method planned hybridization within P. avium and P. cerasus. Combined with the selection from the natural populations, the method resulted in realization of two sweet cherry ('Asenova Rana' and 'Čarna') and five sour cherry cultivars ('Čačanski Rubin', 'Šumadinka', 'Sofija', 'Nevena' and 'Iskra'), three hybrids in the procedure of recognition, and numerous being intensively studied. Current sour cherry breeding work is based on the use of domestic genotypes, well adapted to the environmental conditions of the area (either obtained by planned hybridization or indigenous), and foreign genotypes – tolerant to diseases, with high cropping potential and good fruit quality. Different aspects of reproductive biology in cherries – flowering phenology, pollen tube growth in vitro and in vivo (pollen tube growth dynamics, pollen-pistil interactions in the style and ovary), cytoembryology (ovule development stage, viability of ovule and embryo sac, early embryogenesis), are among the main research activities at FRI. Within the past decade, the research on gametofitic self-incompatibility (GSI) in cherries has been advanced by identification of S-haplotypes in cultivars, landraces and hybrids using consensus, specific and dCAPS primers to reveal S-RNase and SFB functional/non-functional variants. Besides the GSI, other possible types of pollen-pistil interactions have also been considered, primarily in the context of temperature conditions during the flowering. Nowadays, within the CherrySeRB project whose FRI is the leading institution, characterization of the indigenous genotype potential for desirable reproductive properties and defining ʻgood reproductive behaviour cherry modelʼ that can face warmer temperature conditions during the flowering are in focus. The main CherrySeRB idea is connection of production challenges arising from climate change and the richness of Serbian and Balkan cherry germplasm that is still unused enough, which represents a novelty in breeding approach, applicable to other fruit species.