Читать книгу Principles of Plant Genetics and Breeding - George Acquaah - Страница 367

Gynogenesis, using ovules or ovaries, has been achieved in species such as barley, wheat, rice, maize, tobacco, sugar beet, and onion. The method is less efficient than androgenesis because only one embryo sac exists per ovary as compared to thousands of microspores in each anther. Ovaries ranging in developmental stages from uninucleate to mature embryo sac stages are used. However, it is possible for callus and embryos to develop simultaneously from gametophytic and sporophytic cells, making it a challenge to distinguish haploids from those of somatic origin. Generally, gynogenesis is selected when androgenesis is problematic (as in sugar beet and onion).