Comparative analysis of transgenic rice plants obtained by Agrobacterium-mediated transformation and particle bombardment

Abstract

We compared rice transgenic plants obtained by #Agrobacterium-mediated and particle bombardment transformation by carrying out molecular analyses of the T0, T1 and T2 transgenic plants. #Oryza sativa japonica rice (c.v. Taipei 309) was transformed with a construct (pWNHG) that carried genes coding for neomycin phosphotransferase (nptII), hygromycin phosphotransferase (Hyg(sup)r), and Beta-glucuronidase (GUS). Thirteen and fourteen transgenic lines produced via either method were selected and subjected to molecular analysis. Based on our data, we could draw the following conclusions. Average gene copy numbers of the three transgenes were 1.8 and 2.7 for transgenic plants obtained by #Agrobacterium and by particle bombardment, respectively. The percentage of transgenic plants containing intact copies of foreign genes, especially non-selection genes, was higher for #Agrobacterium-mediated transformation. GUS gene expression level in transgenic plants obtained from #Agrobacterium-mediated transformation was more stable overall the transgenic plant lines obtained by particle bombardment. Most of the transgenic plants obtained from the two transformation systems gave a Mendelian segregation pattern of foreign genes in T1 and T2 generations. Co-segregation was observed for lines obtained from particle bombardment, however, that was not always the case for T1 lines obtained from #Agrobacterium-mediated transformation. Fertility of transgenic plants obtained from #Agrobacterim-mediated transformation was better. In summary, the #Agrobacterium-mediated transformation is a good system to obtain transgenic plants with lower copy number, intact foreign gene and stable gene expression, while particle bombardment is a high efficiency system to produce large number of transgenic plants with a wide range of gene expression. (Résumé d'auteur