Abstract

Agrobacterium tumefaciens strain LBA4404 carrying the pBI.121 binary plasmid was used in transformation to introduce the gus (ß-glucuronidase/GUS) gene into teak shoot-tissues. In vitro regenerated shoots from various teak clones, i.e. the ITB, GT, P97, P96, P75, P20, and P108 clones were vacuum-infiltrated for 5 min in the suspension culture of A. tumefaciens. Seven days after selection period, the evidence of GUS activity in inoculated teak shoot-tissues was histochemically confirmed. The percentage of GUS-positive shoots per total numbers of evaluated shoots was calculated to estimate the efficiency of transient-transformation. Results indicated that the percentage of GUS-positive shoots varied among teak clones. The highest percentage of shoots with GUS activity (94.6%) was observed from the P108 clone and the lowest percentage (38.9%) was from the P20 clone. High frequencies of GUS expression were observed mostly in leaf and internodal tissues of teak shoots and less detected in young tissues of shoot-tips.

Key words: Agrobacterium-mediated transformation, Tectona grandis L.f., teak shoot-cultures.

Abbreviation

Abbreviations: GUS, b-glucuronidase; PT, Putative transformed-shoots; TE, Transient-transformation efficiency.