Abstract

MICHELANGELI DE CLAVIJO, Claret C.; ARTIOLI G., Paola I.  and  MEDINA M., Ada M.. Embriogénesis somática en onoto . Agronomía Trop. [online]. 2002, vol.52, n.4, pp.523-541. ISSN 0002-192X.

SUMMARY     Floral buds 0.7 cm in length with uninucleate pollen grains, were removed from 19 annatto, Bixa orellana L., genotypes from the Agronomy Institute’s experimental field, Faculty of Agronomy, Universidad Central de Venezuela, in order to induce callus, somsatic embryos and plantlet regeneration. Anthers were aseptically removed and subjected to five temperature regimes: 8 °C during 0, 2, 4, 6 and 8 days. The effect of three medium cultures Murashige and Skoog (MS), Nitsch and Nitsch and B5 and different growth regulators alone or in combination (naftalenacetic acid (ANA), Kinetine (Kin), 2,4-dichlorophenoxiacetic (2,4-D), Picloram (Pic), indolbutyric acid (AIB), 6-bencilaminopurine (BA) y Thidiazuron (TDZ)) were tested both under ilumination and dark conditions. Somatic embryos were formed on MS medium supplemented with ANA (4 mg l^-1) and BA (2 mg l^-1), under dark conditions at 30 ± 1 °C from the genotypes identified as ‘G1’, ‘41’ and ‘I’. There were no differences among thermal shock treatments. On the other hand, the development of somatic embryos to plantlets was achieved on half MS medium, sugar (20 g l^-1), without growth regulators. Therefore, the efficient regeneration to plantlets through somatic embryogenesis from annatto anthers was achieved with the protocol obtained.

Keywords : Anther; Bixa orellana L.; in vitro culture; embryo; somatic embryogenesis.