African Journal of Biotechnology Vol. 5 (20), pp. 1894-1901, 16 October 2006   

ISSN 1684–5315 © 2006 Academic Journals        

Full Length Research Paper

Synergistic effects of some plant growth regulators on in vitro shoot proliferation of korarima (Aframomum corrorima (Braun) Jansen)

Wondyifraw Tefera^1* and Surawit Wannakrairoj²

¹Plant biotechnology division, Jimma Agricultural Research Center (JARC), Ethiopian Agricultural Research Organization (EARO), P.O. Box 1161, Jimma, Ethiopia.

²Department of Horticulture, Kasetsart University, Kampaengsaen campus, Nakhon Pathom 73140, Thailand.

*Correspondence author. E-mail: wondyfraw@yahoo.com. Tel: +251-917801708. Fax: +251471111999.

Abbreviations: BA - N⁶-benzyladenine; CW - coconut water, IMA - imazalil; MS - Murashige and Skoog (1962) medium; PBZ - paclobutrazol; TDZ - thidiazuron.

Accepted 17 October, 2005

The synergistic effects of some plant growth regulators was investigated upon shoot proliferation and growth of korarima (Aframomum corrorima (Braun) Jansen), an important culinary and medicinal plant species native to Ethiopia. Cultures were initiated from axillary bud explants of rhizome using Murashige and Skoog (1962) (MS) medium added with 5% coconut water (CW). The use of 0.5 mg/l thidiazuron (TDZ) in combination with 3 mg/l paclobutrazol (PBZ) gave about 26 shoots/explant (about 12.6-fold than the control) within eight weeks time. Shoot multiplication was also enhanced when TDZ at 0.5 mg/l was simultaneously used with either 2 mg/l imazalil (IMA) or 3 mg/l N⁶-benzyladenine (BA) in the culture medium. Subsequent shoot elongation and development of functional roots was attained after one to three monthly-subcultures on a plant growth regulator (PGR)-free basal medium. The protocol developed from the present study could be used for the large-scale multiplication of A. corrorima by tissue culture.

Key words: 6-benzyladenine, imazalil, korarima, micropropagation, paclobutrazol, thidiazuron, Zingiberaceae.