Resumen

PEREZ H, Galid Y; MICHELANGELI DE CLAVIJO, Claret C  y  MEDINA M, Ada M. In vitro morphogenesis of dracena. Agronomía Trop. [online]. 2006, vol.56, n.4, pp.577-583. ISSN 0002-192X.

In order to study in vitro morphogenesis of Dracena sanderiana, two different explants in MS medium at 29±2 ºC were evaluated. The effect of 2,4-D plant growth regulator alone (0,5; 1,0 and 1,5 mg l^-1) or in combination with kinetine (0,5 mg l^-1) in dark conditions, and BA (0,5; 2,0 and 3,5 mg l^-1) containing myo-inositol (200 mg l^-1) under illumination (16-h photoperiod) were tested. Shoot explants produced callus and roots on 0.5 mg l^-1 2,4-D medium after 60 days of cultivation. Callus tissue was formed on leaf sheath and shoot explants at a rate of 20% on a medium supplemented with 2,4-D and kinetine. On the other hand, adventitious shoot buds were developed on nodal explants both on a growth-regulator-free medium and BA-containing medium. At higher concentrations, BA enhanced the number of adventitious shoots but smaller in size. After 210 days, the regenerated shoots were rooted either on MS medium containing 0,5 mg l^-1, or briefly immersed in ANA solution of the same concentration and directly potted in a sterilized perlite-vermiculite mixture under mist conditions. The regenerated shoot buds cultured from 3,5 mg l^-1 BA medium failed to stimulate rooting, probably due to a residual effect of BA. However, all the other treatments were effective. Roots were formed at a 40-80% rate on ANA containing medium and up to 100% of the shoots rooted under mist conditions; the number of roots regenerated were highest when shoots were greater than 4 cm in length.

Palabras clave : Dracena sanderiana; in vitro culture; morphogenesis.