Embryo rescue, for the production of F1 hybrids, in English rose

Abstract

The ability to recover embryos from achenes resulting from two sexual crosses of English rose varieties was investigated. Functional germination of recovered (rescued) embryos was considerably higher than for seed material when germinated conventionally. This technique also enabled the germination process to be fully controlled, and the aseptic techniques employed, avoided death of the germinating embryo due to fungal or bacterial infection. Seedlings, produced from recovered embryos, were successfully transferred to glasshouse conditions and matured to flowering plants. Many such plants exhibited combined floral characteristics of the two parent lines. The effects of media type, carbohydrate source and specifically the growth regulator BAP on the germination of recovered embryos was also assessed. The low percentage germination observed for achenes as used in this study, was due to both physical and chemical restrictions on the embryo. It is now therefore possible, to use embryo rescue techniques on English roses to recover flowering plants, of potential commercial value, that would normally be lost after sexual crossing.