IN-VITRO CULTURE OF ZYGOTIC EMBRYOS OF TAXUS SPECIES

An embryo culture method overcomes the lengthy dormancy requirement of Taxus L. spp. (yew) seeds. When zygotic embryos excised from mature T. brevifolia L. seeds were cultured in darkness for 4 weeks on one of three basal salt media (B5, Litvay, and Murashige and Skoog), radicle emergence and seedling development was highest on B5 basal salt medium. After 1 to 2 weeks on B5 basal salt medium, seedling development of T. brevifolia, T. cuspidata L., T. baccata L., and T. baccata stricta L. ranged from 2 % to 36 %. BA at 2.25 mum had no effect on radicle emergence; 22.5 muM prevented it. Embryos excised from mature or nearly mature seeds had the highest frequency of radicle emergence and seedling development. Cultured embryos developed seedlings in only 8 to 10 weeks.