Know more

About cookies

What is a "cookie"?

A "cookie" is a piece of information, usually small and identified by a name, which may be sent to your browser by a website you are visiting. Your web browser will store it for a period of time, and send it back to the web server each time you log on again.

Different types of cookies are placed on the sites:

  • Cookies strictly necessary for the proper functioning of the site
  • Cookies deposited by third party sites to improve the interactivity of the site, to collect statistics

Learn more about cookies and how they work

The different types of cookies used on this site

Cookies strictly necessary for the site to function

These cookies allow the main services of the site to function optimally. You can technically block them using your browser settings but your experience on the site may be degraded.

Furthermore, you have the possibility of opposing the use of audience measurement tracers strictly necessary for the functioning and current administration of the website in the cookie management window accessible via the link located in the footer of the site.

Technical cookies

Name of the cookie

Purpose

Shelf life

CAS and PHP session cookies

Login credentials, session security

Session

Tarteaucitron

Saving your cookie consent choices

12 months

Audience measurement cookies (AT Internet)

Name of the cookie

Purpose

Shelf life

atid

Trace the visitor's route in order to establish visit statistics.

13 months

atuserid

Store the anonymous ID of the visitor who starts the first time he visits the site

13 months

atidvisitor

Identify the numbers (unique identifiers of a site) seen by the visitor and store the visitor's identifiers.

13 months

About the AT Internet audience measurement tool :

AT Internet's audience measurement tool Analytics is deployed on this site in order to obtain information on visitors' navigation and to improve its use.

The French data protection authority (CNIL) has granted an exemption to AT Internet's Web Analytics cookie. This tool is thus exempt from the collection of the Internet user's consent with regard to the deposit of analytics cookies. However, you can refuse the deposit of these cookies via the cookie management panel.

Good to know:

  • The data collected are not cross-checked with other processing operations
  • The deposited cookie is only used to produce anonymous statistics
  • The cookie does not allow the user's navigation on other sites to be tracked.

Third party cookies to improve the interactivity of the site

This site relies on certain services provided by third parties which allow :

  • to offer interactive content;
  • improve usability and facilitate the sharing of content on social networks;
  • view videos and animated presentations directly on our website;
  • protect form entries from robots;
  • monitor the performance of the site.

These third parties will collect and use your browsing data for their own purposes.

How to accept or reject cookies

When you start browsing an eZpublish site, the appearance of the "cookies" banner allows you to accept or refuse all the cookies we use. This banner will be displayed as long as you have not made a choice, even if you are browsing on another page of the site.

You can change your choices at any time by clicking on the "Cookie Management" link.

You can manage these cookies in your browser. Here are the procedures to follow: Firefox; Chrome; Explorer; Safari; Opera

For more information about the cookies we use, you can contact INRAE's Data Protection Officer by email at cil-dpo@inrae.fr or by post at :

INRAE

24, chemin de Borde Rouge -Auzeville - CS52627 31326 Castanet Tolosan cedex - France

Last update: May 2021

Menu Institut Sophia Agrobiotech Logo Marque Etat - République Française Logo_INRAE_noir Logo Université Côte d'Azur CNRS

Home page

Institut Sophia Agrobiotech

UMR INRA - Univ. Nice Sophia Antipolis - Cnrs

http://www.paca.inra.fr/institut-sophia-agrobiotech_eng/

Soutenance de thèse - Antoine PASQUIER

Vendredi 10 Décembre 2021 - 14:00 - Visioconférence par ZOOM

Soutenance de thèse
Antoine PASQUIER : "De la preuve de concept à l’optimisation : L’utilisation d’une espèce d’acarien prédateur pour contrôler la population de la Chrysomèle des racines du Maïs (Diabrotica virgifera virgifera) (LeConte, 1868)"

devant le jury composé de :

Président du jury :

  • Anne-Marie Cortesero : Professeur, Université de Rennes, France 

Rapporteurs :

  • Outreman Yannick : Professeur, Agro-campus Ouest, France
  • Gard Benjamin : Ingénieur de recherche, CTIFL, Bellegarde, France
  • Toepfer Stefan : Directeur de recherche, CABI, Hongrie. 

Examinateur : 

  • Cortesero Anne-Marie : Professeur, Université de Rennes, France 

Invité :

  • Andrieux Thibault : Ingénieur de recherche, Bioline Agroscience 

Directeurs de thèse :

  • Vercken Élodie : Directrice de recherche, INRA UMR 1355, Sophia Antipolis, France

 

Abstract :

Maize is the most important cereal crop in the world (162 million hectares). It plays a major role in human and animal nutrition and its cultivation occupies about 9% of the useful agricultural area in Europe. Since its arrival in Europe in 1992, the corn rootworm, belonging to the order Coleoptera, has threatened this important crop. The larval stage of this organism is particularly harmful to plants because it attacks the underground parts of this cereal causing yield losses that can reach 80% of the crop's potential in the most critical cases. Chemical pesticides, the use of Bt GMOs and crop rotation alternating soybeans and corn are the main control methods for this pest currently. However, studies have shown that some populations are resistant to these insecticides and are able to (i) persist in the soil longer and (ii) expand their host range by attacking soybean roots. In this context, there is a need to explore new crop protection methods that will allow a more integrated control of this pest. A study recently demonstrated the potential role of soil predatory mites as biological control agents. These organisms are at the top of trophic chains in agricultural systems and have already shown strong abilities to control populations of subterranean pests. The main objective of my thesis is to develop a biological control strategy agronomically  and economically viable to control corn rootworm. First, I evaluated the predation capacity of three soil mites (Stratiolaelaps scimitus, Gaeolaelaps aculeifer and Macrocheles robustulus) on the early developmental stages of western corn rootworm in the laboratory. These results were conclusive and one of the three candidates particularly attracted our attention: G. aculeifer. This predatory mite showed a higher predation capacity on the first larval stage of the pest.  In a second step, I studied the effect of the presence and the density (100, 500 and 1000 mites per corn plant infested by the pest) of these predatory mites on the western corn rootworm population under semi-controlled conditions.This experiment showed that the mite densities tested were all effective in protecting the maize plant. Finally, and in order to optimize the effectiveness of these predatory mites as a biocontrol agent, I studied the population dynamics of these predators when a low density of predatory mites has been introduced at the time of seeding (Predator-in-first method) and in the presence of alternative food, in a field naturally infested by corn rootworm. These experiments allowed me to identify an application method that would facilitate the introduction of the biological control solution and reduce its cost. My work will provide essential information in understanding the biological control potential of these previously understudied soil organisms. 

Keywords : Predatory mites, Gaeolaelaps aculeifer, biocontrol, predator-in-first