Abstract: Syringa L. is the famous ornamental shrub in China, but its embryo always dies before seed mature during cross breeding, and hence, the breeding work is very difficult. The main object of this study is using embryo culture in vitro to get the seedling directly and to improve the succeed rate of cross breeding. The factors that influenced the embryo culture were researched in detail. The results showed that the optimal medium for embryo culture was Monnier, and the second was MSor LS, which meant that the embryo of Syringa needed abundant macro elements and microelements, especially Ca²⁺ and K⁺. The optimal sugar concentration was 50 g·L^-1 . At this level, the sugar could offer enough nutrition and high osmotic pressure for embryo. When the embryo age was 50～60 days, the culture was easy to be succeed. At this time, the cotyledon in ovule began to form, or organ began to differentiation, so, the embryo was very easy to germinate, and the seedling was very easy to form. Proper coconut milk, glutamic acid or glutamine, and activated charcoal could improve the germination and growth of the embryo. When the BA of low concentration (0.01 mg·L^-1) was joined in the medium, the germination rate could be improved. The best NAA concentration was 0.01 mg·L^-1 .

Key words: Syringa L, Embryo, Culture in vitro , triclosan, metabolites, ecological risk., toxic effect