Embryo development and germination of Cyclamen persicum have been comparatively characterized for zygotic and somatic embryos with regard to mitotic activity and morphology in order to identify developmental abnormalities in somatic embryogenesis. Zygotic embryo development proved to be highly synchronous with distinct periods of cell division, cell elongation and embryo maturation within a total period of 17 weeks of seed development. Somatic embryo development was accomplished within only 3 weeks, resulting in a mixture of morphologically highly variable embryos. No distinct developmental periods could be identified and no reduction of the mitotic activity was discovered for non-desiccated somatic embryos. Controlled desiccation of somatic embryos severely reduced their germination rate, demonstrating resemblance of somatic embryos to recalcitrant seeds, whereas zygotic Cyclamen seeds could be characterized as typically orthodox.

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In order to introduce valuable traits from wild species of Cyclamen into C. persicum cultivars, crosses were made between C. persicum 'ReinweiB' and C. purpurascens. Crossing barriers between C persicum 'ReinweiB' and C. purpurascens were due to late-acting incompatibility reactions. Interspecific hybrids were obtained by using ovary culture. The highest number of embryos was achieved from placentas excised 21 days and 35 days after pollination and transferred to MurashigeSkoog (M.S.)-medium containing 6% sucrose and 1% agar. The hybrids showed a habit and a chromosome number intermediate between the parents. The fragrant fiowers were pale red-purple. The chromosome number in root tips was determined as 2« = 41 while in C persicum it is 2« = 48 and in C purpurascens 2n = 34. Due to the different parental chromosome sizes, chromosomes of distinct size were still observed in the hybrid. Pollen viability varied between 0.3 and 34.0%. Parents and interspecific hybrids also showed differences in the DNA content of leaf tissue. Flow cytometric analyses were useful in the early identification of hybrids.

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