*Author for Correspondence.
Forest Research Institute Malaysia,
52109 Kepong, Selangor Darul Ehsan,
Malaysia.
Telephone: 603-62797151, Telefax: 603-62804614,
Email: norwatia@frim.gov.my

Abstract.
A biolistic particle delivery system was used to transform nodal segments of teak (Tectona grandis). The introduced DNA contained a β-glucuronidase (uidA) and hygromycin phosphotransferase (hpt) genes each fused to the CaMV 35S promoter. Merely 70% from the bombarded nodal segments survived at the first screening and the survival rate was further reduced to 15% following the second screening. Subsequently, only 8% of the plants derived from bombarded nodal segments reached the nursery stage. Expression of the uidA gene was detected histochemically in putative transformed tissues and subsequently in regenerated plants. The presence of the uidA gene and its integration into the teak genome was demonstrated using PCR and PCR-Southern hybridization. PCR analyses using uidA primers showed that 59% of the putative transformed plants selected for hygromycin resistance were transformed with the gene encoding β-glucuronidase. The expression of uidA gene in transformed plant was again confirmed by RT-PCR analysis. This is the first report of a method to transform genetically teak.