Inheritance of the ‚bud bloomer‘ trait in Calluna vulgaris.
The so-called “bud bloomers” are economically very important cultivars of Calluna vulgaris (Ericaceae), a major ornamental crop of the European horticultural sector. Within the bud bloomer group, the diplocalyx and the polystyla type can be distinguished. Both bud bloomer types have an extended flower longevity. Due to a dysfunction in flower opening, they display a duplication of calyx organs and a loss of petals. However, they differ with regard to flower whorl 3: whereas stamens are missing in the diplocalyx type, stamens show a carpelloid character in the polystyla type. The genetic basis of the bud blooming flower type is still unclear. A series of crosses was performed to evaluate the number of loci and alleles involved in the genetics of the trait ‚flower type‘ in C. vulgaris. From the segregation ratios within the resulting populations, a monogenic inheritance involving three alleles was deduced, assuming that the polystyla genotypes are heterozygous. This hypothesis was verified in additional crossing experiments.
Behrend, A.; Hohe, A. 2016. Inheritance of the ‚bud bloomer‘ trait in Calluna vulgaris. Acta Horticultuae, 1127, 251-258.