General Conference abstract: Plant Breeding Innovation Showcase, online event, May 30 2022
In ornamental plant production, compact growth is often achieved by application of chemical plant growth regulators. To minimize exposure risks and to establish a more sustainable and environmental-friendly plant production, we aimed to generate new cultivars that are less dependent on chemical growth inhibition. In many genera, plants regenerated from tissue co-cultured with wild type Rhizobium rhizogenes are more compact. R. rhizogenes modifies the host plant nuclear genome by inserting oncogenes (rol genes). Expression of these rol genes results in excessive formation of adventitious roots which are referred to as hairy roots. Plants regenerated from hairy roots typically display dwarfism, extensive lateral branching and reduced apical dominance. These traits are reminiscent to the compactness obtained upon treatment with chemical growth inhibitors. We were able to introduce the rol genes into different types of ornamentals, a.o. Osteospermum fruticosum, Sinningia speciosa and Viola spp. During this presentation we will give an introduction on this Ri technology and show the obtained results for some ornamentals. Moreover some future perspectives for this technology will be introduced.