Resumo

VEGA, Rafael et al. Histology of somatic embryogenesis in rice (Oryza sativa cv. 5272). Rev. biol. trop [online]. 2009, vol.57, suppl.1, pp. 141-150. ISSN 00347744.

Rice (Oryza sativa cv. 5272) embryogenic calli were obtained from mature zygotic embryos culture on Murashige & Skoog (1962) medium supplemented with 2.5 mg/l 2,4- dichlorophenoxyacetic acid. Histological analysis of somatic embryogenesis revealed that after two weeks of culture of explants on the callus induction medium, somatic embryo development began with a cluster of proembryogenic cells in the peripheral region of the calli. The outer cell layer of embryogenic calli consisted of small and isodiametric cells with a dense cytoplasm and a prominent nucleus and nucleolus; whereas the inner cell layer is composed of large cells with small nucleus and large vacuole. These embryogenic cells underwent a series of organized divisions and formed the proembryo with a well-defined protodermis. Rev. Biol. Trop. 57 (Suppl. 1): 141-150. Epub 2009 November 30.

Palavras-chave : Oryza sativa; rice; in vitro culture; histology; somatic embryogenesis; morphogenesis; Costa Rica.