In vitro regeneration of Acacia mangium via organogenesis

Plant regeneration of Acacia mangium was achieved through organogenesis in callus cultures. Calli were induced from five types of explants (embryo axes and cotyledons of mature zygotic embryos as well as leaflets, petioles and stems of seedlings) of A. mangium on MS (Murashige and Skoog, 1962) basal medium containing 9.05 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 13.95 μM kinetin (KT). Green or green purple compact nodules containing clusters of meristematic centers were induced in these calli after transfer to MS basal medium containing 1.14–22.75 μM thidiazuron (TDZ) and 1.43–2.86 μM indole-3-acetic acid (IAA). A combination of 4.55 μM TDZ and 1.43 μM IAA promoted the highest percentage of calli to form nodules, in 8–11% of calli derived from cotyledons, embryo axes, leaflets or petiole and in 4% of calli derived from stems. Twenty-two percent of the nodules formed adventitious shoots on MS basal medium containing 0.045 μM TDZ. Shoots were elongated on MS medium containing 0.045 μM TDZ supplemented with 7.22 μM gibberellic acid. The medium containing 10.75 μM NAA and 2.33 μM KT promoted rooting of 10% of the elongated shoots. Plantlets grew up well in the green house. This revised version was published online in June 2006 with corrections to the Cover Date.