General Conference abstract: The 22nd International Conference - Life Sciences for Sustainable Development, Romania, September 28-30 2023


Oral presentation

Adriana Aurori, Raluca Dumitrița Lazar, Rodica Pop, Cristian Radu Sisea

Introduction: The composite plant system, consisting of wild type shoots and transformed roots, is a useful tool for analysing the transformed roots functionality when the availability of fully transformed plants is restrictive. Very often, a composite system is considered as such if even a transformed root is present, but, in order to be meaningful, it is desirable that the transformation efficiency, defined by the ratio of transformed/non-transformed roots, to be as high is possible. This condition is difficult to be achieved using the protocol of transformation with Rhizobium rhizogenes (Parks and Yordanov, 2020), the only one available for sunflower up to now.

Aims: The study aimed at optimizing the transformation protocol for sunflower, in order to increase the efficiency of regeneration of transformed roots in the composite plants (Ri roots).

Materials and Methods: The injection of wild type R. rhizogenes suspension in the hypocotyl of one week old plants, at one cm above the natural roots, leads, within a week, to the callus growth, at the wounding site. After obtaining the callus, the natural roots can be removed allowing the adventitious roots to develop. After two weeks the tips of the newly formed roots, ten for each plant, were collected and subjected to qPCR analysis.

Results: From the tested plants, 100% were transformed with a transformation efficiency of up to 80-100%. Only the first developed roots were analysed, so overestimation of transformation efficiency is expected, since new roots can grow from the non-transformed tissue. Following their development, the composite plants show more vigour than the control, with better developed foliage, suggesting that the transformed roots are functioning well.

Conclusion: This is a new non-GMO technology method for sunflower transformation and it seems promising for obtaining a good composite system. This would facilitate the performance analysis of the Ri roots in normal and water deficient conditions, allowing for future developments regarding sunflower tolerance to drought.

Keywords: genetic transformation, non-GMO plants, root traits


  1. Parks T., Yordanov Y.S. (2020). Composite plants for a composite plant: an efficient protocol for root studies in the sunflower using composite plants approach. Plant Cell, Tissue and Organ Culture (PCTOC). 140:647-659.

Acknowledgements: This work was supported by FACCE-JPI and RootsPlus, a SusCrop –

ERA-NET project funded by the national funding agencies of partner countries, including the

Executive Agency for Higher Education, Research, Development and Innovation Funding (UEFISCDI)