IN VITRO TECHNIQUES FOR ORNAMENTAL BREEDING

Breeding of ornamentals requires, more than in other crops, techniques for overcoming crossing barriers because many crosses are made between distant related species and even genera in order to add as much as possible natural genetic variation to the breeding lines. In this review the most commonly used in vitro techniques for pollination, fertilization and embryo culture are presented. The technique of somatic hybridization is applied in several ornamentals. The result of an interspecific cross often ends with sterility problems of the hybrid. Some methods to solve this problem are mentioned here. Also attention is given to androgenesis and gynogenesis in order to develop a regeneration system through sexual gametes useful for the production of hybrid seeds in several important ornamentals. Special attention will be given to the development of a gene delivery system in monocotyledonous ornamentals.