Supervisory authorities

CNRS UPS Enseeiht

Search




Home > News

Maxime BAFOIL’s Thesis Defense

by Laurence Laffont - published on , updated on

Maxime BAFOIL’s thesis defense intitled Stimulation de la germination des graines et de leur croissance par plasmas froids à la pression atmosphérique (Stimulation of seeds’ germination and growth by cold plasmas at atmospheric pressure) will be taking place on Monday, November 2nd 2020 at 10 am at the LAPLACE, UPS site, 118 Route de Narbonne 31062 TOULOUSE Cedex 9.

The thesis was supervized by Mr Mohammed YOUSFI et Mr Christophe DUNAND.

According to the currect circumstances, the defense will by held through video.
Anyone may access it using Zoom (updated on 11/02/2020) :

https://zoom.us/j/99056759720?pwd=MUZOdG03VXJGRHUxd3hacEN0KzloZz09

ID de réunion : 990 5675 9720
Code secret : 7cwvtp

The aforementioned link will be working 15 mn before the thesis defense begins. Please, do not forget to turn off your microphone and camera.

Jury:
Mr Mohammed YOUSFI - Université Toulouse III - Paul Sabatier - Thesis co-supervisor
Mrs Farzaneh AREFI KHONSARI - LISE - CNRS UMR8235, Université Sorbonne Université - Rapporteur
Mr Loïc RAJJOU IJPB, Institut Jean-Pierre Bourgin (INRA, AgroParisTech, CNRS, Université Paris-Saclay) - Rapporteur
Mr Thierry DUFOUR - Sorbonne Université - Reviewer
Mr Christophe DUNAND - Université Toulouse III - Paul Sabatier - Thesis co-supervisor
Mr Nofel MERBAHI - Université Toulouse III - Paul Sabatier - Reviewer

Abstract :

This work is part of the convergence of the fields of plasma physics and plant biology. The aim of this thesis is to provide answers regarding the mechanisms involved in the effects of cold plasmas at atmospheric pressure upon the germination and development of plants.

The model plant in plant biology Arabidopsi Thaliana is used in this work. The plasmas used are air or helium plasmas in direct or indirect treatment. The effects are noted on the germination of the seeds for the direct treatment and on the development of the aerial parts for the indirect treatment via plasma activated water (PAW).

The first results show a positive effect of the air plasma treatment initiated with a dielectric barrier discharge on a floating electrode (FE-DBD). Indeed, this treatment allows an increase in the germination rate but above all an increase in the speed of germination. Analysis of the seed permeability revealed a change in the surface of the seeds. Subsequently, observations of the surface of the seeds make it possible to observe a physical effect of the plasma on the surface. Analysis of the surface residues shows a change in lipid composition. This being strongly correlated with germination; these results allow the identification of a way of understanding the effects of plasmas on germination.

In another part, the indirect treatment of plants with PAW has the effect of increasing the growth rate. Since plasma creates a certain number of reactive oxygen and nitrogen species, this treatment would act as a plant-stimulating fertilizer.

Keywords:

Cold plasma, Germination, Arabidopsis Thaliana, Reactive species, Plasma-agriculture