| Genetic variation in development of maize cultivar can be enhanced using genetic transformation. An efficient procedure of genetic transformation ultimately can accelerate the process of cultivar development. Transgenic maize plants have been produced from Agrobacterium-mediated transformation using explants of immature embryos of A188 and HiII. HiII is a hybrid derived from A188 x B73. The objectives of this study were to evaluate the efficiency of maize transformation using strain of Agrobacterium C58C1; and compare the efficiency of transformation using three strain of Agrobacterium, i.e., C58C1, NTL4-Cry5, dan LBA4404. The evaluation was based on GUS transient expression and the proportion of transgenic plantlets. Explants of immature embryos were isolated from immature ears harvested 11-13 days after pollination. Then explants were inoculated with Agrobacterium, cultured in co-cultivation medium for 1-2 days, then in delay medium for 7-14 days, in selection medium for 4 x 14 days, in regeneration medium, and finally in germination medium. Based on assay at 2 days after inoculation, GUS transient expression at scutelar side of explants inoculated with strain NTL4-Cry5 was higher than that of inoculated with C58C1 or LBA4404. However, the results of four experiments indicated that transgenic plantlets were only produced from explants inoculated with strain C58C1, with efficiency 1,3-5,8 %. |