Buletin USAMV-CN, 63/2006 (-) ISSN 1454-2382 BREEDING FOXGLOVE (DIGITALIS SP.) FOR ORNAMENTAL AND/OR MEDICAL PURPOSES Ardelean, M. 1 , Ana-Maria Costea 2 , Mirela Cordea 1 1 University of Agricultural Sciences and Veterinary Medicine, 3-5 Manastur Street, 400372 Cluj-Napoca, Romania, email: mardelean@usamvcluj.ro 2 City Hall, Municipality of Blaj, Romania Key-words: foxglove, diallel crosses, plant characters, heritability, GCA, SCA. Abstract. Complete diallel crosses were performed, in 2000, involving four foxglove cultivars. Parents and F 1 hybrids were grown in two locations and, based on results obtained, heritability (both in wide and narrow sense) as well as the phenotypic and genotypic correlations among the studied characters were estimated. Values of the general (GCA) and specific combining ability (SCA) were also computed. There have been noted quite a few traits with a high heritability in wide sense (H = 0.70-0.98). In very few instances the high values of wide sense heritability have been accompanied by appreciable values of narrow sense heritability. Additive effects of polygenes, emphasized by high GCA values in several characters, suggest that, in foxglove, for most of the these characters, there might be found distinct groups of polygenes with positive effects and other groups of polygenes with negative ones. SCA showed significant values for most of plant and flower characters under study which could be a proof that, in foxglove, there are fair chances to develop commercial hybrids with an obvious heterosis in the expected direction (negative or positive). Commercial hybrids could be the conventional breeding solution to developing foxglove cultivars exhibiting both high ornamental and medical value. INTRODUCTION Out of the countless “medicine plants”, known and used both in ancient times and nowadays, probably foxglove is the most beautiful flower. Known mainly as a provider of cardiotonic glycosides, foxglove has lately considerably widened its area of use, now covering kidney diseases as well as epilepsy, delirium tremens, acute mania etc. (MIHALEA, 1969; MUNTEAN et al., 1995). Besides these medical utilizations, many horticulturists consider foxglove a valuable ornamental plant (SELARU, 1998). The present paper contains experimental results obtained by testing four foxglove cultivars as well as the F 1 generations obtained through diallel crosses among these cultivars, with the declared intention of creating a valuable new material in which selection could be applied both for medicinal and ornamental purposes. MATERIAL AND METHOD Four cultivars of foxglove have been employed, three (Magurele, Alba and Excelsior) belonging to D.purpurea and one (Lanata 1) to D.lanata. Diallel crosses were performed in 2000, parental and F1 hybrid populations being grown in 2001 - 2002 in two locations (Blaj and Bucharest). Heritability, both in wide and narrow sense, was computed for the most important characters of plant and flowers. Phenotypic and genotypic correlation indices were estimated among all plant and flower characters under study to help with evaluation of