Phenotyping Protocol for Sour Cherry (Prunus CerasusL.) to Enable a Better Understandingof Trait Inheritance

A phenotyping protocol for sour cherry (Prunus cerasusL.) was developed to include evaluations of phenology, productivity and fruit quality. Traits of particular importance for mechanical pitting for processed sour cherries were included such as estimates of fruit and pit shape and pit freestone/clingstone. To evaluate the correlations among the phenotypic traits in the protocol, the traits were evaluated on sour cherry germplasm included in the RosBREED project ( www.rosbreed.org). Correlations among the values of these phenotypic traits supported the need to evaluate linear measurements of the fruit and pits as fruit and pit weights were weakly and not significantly correlated with fruit and pit shape, respectively. Highly significant correlations between some traits suggested a genetic correlation as opposed to a correlation based on shared tree/fruit growth and development. These include highly significant correlations between fruit firmness and bloom date and between yield and fruit flavor (measured as soluble solids concentration and acidity). This phenotyping protocol will enable the collection of trait data that can be used in future studies to determine the genetic control of traits important for new sour cherry cultivars.