ORIGINAL PAPER Regeneration and genetic transformation of Hagenia abyssinica (Bruce) J.F. Gmel. (Rosaceae) with rolB gene Tileye Feyissa Æ Li-Hua Zhu Æ Legesse Negash Æ Margareta Welander Received: 8 June 2006 / Accepted: 22 December 2006 / Published online: 23 January 2007 Ó Springer Science+Business Media B.V. 2007 Abstract The effects of growth regulators, wounding and antibiotics on regeneration of Hagenia abyssinica were investigated and the rolB gene was introduced into this species by Agrobacterium-mediated transformation. Regen- eration was affected by type of growth regula- tors, wounding and antibiotics. Up to 100% regeneration could be obtained. Three trans- formed clones (T1, T2.1, T2.2), confirmed by PCR and Southern blot, were obtained only by excluding kanamycin from the selection medium 6 weeks after culture, followed by selection during shoot multiplication. RT-PCR revealed strong expression of rolB gene in shoots and roots of all the transgenic clones, but from leaf samples, it was detected only in T1. Rooting frequency was 77% (T1), 50% (T2.1), 57% (T2.2) and 0% for control shoots on growth regulator-free rooting medium. Keywords Agrobacterium-mediated transformation Á Antibiotic Á Growth regulator Á Rooting Á Wounding Abbreviations 2,4-D 2,4-dichlorophenoxyacetic acid BAP 6-benzylaminopurine IAA indole-3-acetic acid IBA indole-3-butyric acid MS Murashige and Skoog NAA a-naphthaleneacetic acid nptII neomycinphosphotransferase II rolB root locus B Introduction Hagenia abyssinica (Bruce) J.F. Gmel is a multi- purpose dioecious tree belonging to the family Rosaceae. It is the only species representing the genus Hagenia. It has short trunk, thick branches, compound leaves, with tree height reaching up to 20 m. The female and male trees are distinguished with certainty only after flowering. Since the species is confined to the mountains of tropical Africa, it has been characterized as a typical example of Afromontane endemism (Friis 1992). Owing to the high demand for its timber, H. abyssinica is one of the most endangered tree T. Feyissa Á L.-H. Zhu (&) Á M. Welander (&) Department of Crop Science, Swedish University of Agricultural Sciences, P.O. Box 44, 230 53 Alnarp, Sweden e-mail: Li-Hua.Zhu@vv.slu.se M. Welander e-mail: Margareta.Welander@vv.slu.se T. Feyissa Á L. Negash Department of Biology, Faculty of Science, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia 123 Plant Cell Tiss Organ Cult (2007) 88:277–288 DOI 10.1007/s11240-006-9200-5