Cysteine and acetosyringone are the two important parameters in Agrobacterium-mediated transformation of rose hybrid (Rosa hybrida L.) cv. Nikita

Abstract

An Agrobacterium-mediated transformation method for rose hybrid Nikita has been developed by using Agrobacterium tumefaciens, EHA 101 harboring the disarmed plasmid pIG 121-Hm with the eukaryotic hpt11 gene, which confers resistance to the antibiotic hygromycin, as well as an intron containing β-glucuronidase (gusA) gene. In order to optimise the conditions for rose hybrid Nikita transformation, several factors known to influence Agrobacterium-mediated DNA transfer were examined using transient gusA gene expression. Nodal segment and leaf segment were examined. Two parameters, different cysteine concentrations (0, 50, 100, 150 and 200 mg L-1) and acetosyringone concentrations (0, 50, 100, 150 and 200 μM) were evaluated to maximize transformation efficiency during co-cultivation in MS medium in both nodal and leaf segments. The inclusion of 100 mg L-1 cysteine and 50 μM acetosyringone in co-cultivation MS medium was proved to increased transient GUS expression in nodal segment and the inclusion of 100 mg L -1 cysteine and 0 μM acetosyringone in co-cultivation MS medium was proven increased transient GUS expression in leaf segment. Overall, the transient GUS expression level in nodal segment was found to higher than in leaf segment. The two optimum parameters concentrations will be applied subsequent transformation work in future with nodal segment as explants to obtained transgenic rose plantlets. © 2007 Academic Journals Inc.