Production and rooting behaviour of rolB-transgenic plants of grape rootstock ‘Richter 110’ (Vitis berlandieri × V. rupestris)

Abstract

Production and rooting behaviour of rolB-transgenic plants of grape rootstock 'Richter 110' (Vitis berlandieri 3 V. rupestris) Abstract Genetic improvement of grape rootstocks is aimed at protection against grape phylloxera and other soil-borne pests and diseases, good rooting and graft compatibility as well as adaptability to a wide range of soil and climatic conditions. Apart from the long evaluation period required, breeding is complicated by the high heterozygosity in grapes. As an alternative to traditional crossing, gene transfer permits addition of single traits, largely without affecting the genetic background of existing valuable cultivars. Here we report on the production and rooting behaviour of transgenic grape rootstock 'Richter 110' carrying the Agrobacterium rhizogenes rolB gene, which is known to promote rooting. Transformation was achieved by co-cultivation of somatic embryogenic callus with Agrobacterium tumefaciens LBA4404 harbouring plasmid pHrB. The T-DNA of pHrB contains the hpt gene, conferring hygromycin resistance, and the rolB gene under control of its own promoter. PCR using transgene-specific primers verified the presence of hpt in all 36 hygromycin resistant clones selected, while only 24 clones also possessed the rolB gene. Rooting behaviour was examined in vitro, using tip, node and internode explants, and in aeroponic culture in the greenhouse, using single-node cuttings. Compared to internodes of non-transgenic 'Richter 110', those of rolB-transgenic clones in general showed significantly higher rooting ability and, in contrast to the former, were able to root profusely even in the absence of auxin. Cuttings of three rolB-transgenic clones in aeroponic culture produced almost twice as many primary roots as those of the non-transgenic control.

Plant Cellular and Molecular Biotechnology: Following Mariotti’s Steps

“…RT-PCR analysis revealed that neither the rolB gene nor its mRNA were detectable in the scion, indicating no translocation from the rootstock to scion. Similar results have been observed in the pear rootstock [88] and in grapes [80]. RolC gene insertion into kiwifruit ( A. deliciosa A. Chev) generated yellow leaves, stunted growth, and reduction of fruit size and flower number, thus was unsuitable for commercial uses [99].…”

Transient GUS and GFP Expression in Spanish Red Cedar (<i>Cedrela odorata</i> L.) Somatic Embryos. Optimization of Bombardment Conditions and Evaluation of Selective Agent Lethal Dose

“…PPT was the most toxic agent, requiring a concentration of 5 µM to kill 100% of calli, followed by 20 µM HYG, 500 µM SPE, and 1 mM KAN. Similar concentrations have been reported to inhibit embryo regeneration of chestnut (Rothrock et al, 2007), grape (Geier et al, 2008), oil palm (Parveez et al, 1997), Eucalyptus (Sartoretto et al, 2002) and poplar (Okumura et al, 2006). The obtained lethal doses could be considered as common for several plant species, however it was very important to establish them for C. odorata because sometimes even slight variations in the physiological conditions of a particular tissue or in its the genetic background may change its susceptibility to the toxicity of a given selective agent (Duke, 1996).…”

Regeneration of transformed plants from hairy roots of Plumbago indica

“…The effect of rolB integration into plants has been extensively studied and is implicated in extensive rootinghairy roots whereby the transformed plants show profuse rooting in the absence of an external auxin supply (Geier et al 2008). rolB has been reported to enhance shoot organogenesis (Altamura 2004).…”