Abstract:
The sweet cherry breeding program begun in 1981 at the CMVF-DCA, University of Bologna, was based on 105 crosses of 22 parents, producing an F1 seedling total of 4,725 bred over a 12 year period.
The main aims being pursued are self-fertility (SF) compact (CH) and/or spur (SH) habit, high fruit quality (size, firmness, flavour) (HQ) and early ripening (ER). Fifteen seedlings have been selected to stage-2 screening.
The SF trait, controlled at the monogenic S locus by the allele S4, is transmitted to approximately 50%, 75% or 100% of the progenies, depending on parental alleles.
The new cultivars 'Sunburst' and 'New Star' appear to have both the S4, and S1 alleles.
The CH trait is usually transmitted by compact mutants, whereas SH can derive either from CH or semi-spur cultivars.
The high quality traits are polygenic with a broad pattern of segregation. 'Lapins' and 'Lambert Compact' have so far performed best for firmness, 'New Star', 'DC Vignola' and 'Lambert Compact' for flavour, 'Sunburst' and 'New Star' for size, and 'Bigarreau Burlat' and 'New Star' for early ripening.
|