干旱区生态环境知识资源中心

A procedure is described for micropropagation of Acacia tortilis subsp raddiana (Forsk) Hayne (Mimosoideae) using embryonic explants. Shoot bud formation from cotyledonary nodes was observed on Murashige and Skoog (MS) medium containing various doses of cytokinins (2.5-5.0 mg/l) viz6-benzyl adenine (BA) and kinetin, with or without incorporation of auxin (0.1-0.25 mg/l) viz 1-naphthalene acetic acid (NAA) and indole acetic acid (IAA). Multiple shoot regeneration (13-15) was achieved on MS medium supplemented with NAA (0.1 mg/l) and BA (5.0 mg/l). Incorporation of auxin, eg, IAA and NAA promoted callusing in the explants. Shoot bud formation was restricted to the cotyledonary node and proximal region of the cotyledons. Scanning electron microscopy showed that shoot bud induction was visible after 5 d of culture. No regeneration of shoot buds from the hypocotyl explants was observed with any treatment used. Half-strength MS medium containing indole butyric acid (3.0 mg/l) was found suitable for rooting in regenerated shoots. In vitro developed plantlets were transferred into soil.