Back To Top

Molecular and physiological regulation of adventitious root (AR) formation in Petunia cuttings in response to nitrogen preconditioning and dark exposure


2012 - 2016

In recent studies of our group it was demonstrated that adventitious root (AR) formation in cuttings of several plant species can be enhanced by high nitrogen supply to the stock plants and in case of petunia can also be stimulated by temporary dark incubation of cuttings. However, the molecular physiological processes behind these effects are still unknown which limits a systematic use in horticulture.

Cooperation Partners

Dr. Mohammad-Reza Hajirezaei
Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung (IPK) Gatersleben

Based on the established microarray for transcriptome studies, a biochemical and a transformation platform, Petunia hybrida will be used to investigate the molecular physiological regulation behind modulation of AR formation in shoot tip cuttings via nitrogen preconditoning and temporary dark exposure of cuttings. The concept relies on the fact that AR formation depends on establishment of the new sink in the stem base and is restricted by competition with the shoot apex for assimilate and nutrient provision. Leaves are considered as potential source organs and auxin is expected to be a key factor. The project follows the hypotheses, that high nitrogen supply to donor plants and dark exposure of cuttings promote AR formation by enhanced nitrogen remobilization within the cutting and enhanced translocation and accumulation of the signalling molecules auxin or nitric oxide in relation to cytokinins. Analysis of auxin and cytokinin levels by GC- and UPLC-MS/MS will be complemented by histochemical localization of auxin activity via the DR5 auxin reporter. The regulatory role of components will be verified by physiological and pharmacological treatments and in transgenic Petunia with a modified expression of candidate genes (gefördert durch die DFG).

Other Projects

Quality assurance in the production of ornamental cuttings

The quality of cuttings is currently being evaluated in young plant production only by external parameters. For direc...

Read More

Molecular physiology of chilling tolerance of Petunia and Euphorbia pulcherrima

Future greenhouse production of ornamental crops in Central and Northern Europe depends on the reduction of energy inputs. Plants with a higher tol...

Read More