Know more

Our use of cookies

Cookies are a set of data stored on a user’s device when the user browses a web site. The data is in a file containing an ID number, the name of the server which deposited it and, in some cases, an expiry date. We use cookies to record information about your visit, language of preference, and other parameters on the site in order to optimise your next visit and make the site even more useful to you.

To improve your experience, we use cookies to store certain browsing information and provide secure navigation, and to collect statistics with a view to improve the site’s features. For a complete list of the cookies we use, download “Ghostery”, a free plug-in for browsers which can detect, and, in some cases, block cookies.

Ghostery is available here for free:

You can also visit the CNIL web site for instructions on how to configure your browser to manage cookie storage on your device.

In the case of third-party advertising cookies, you can also visit the following site:, offered by digital advertising professionals within the European Digital Advertising Alliance (EDAA). From the site, you can deny or accept the cookies used by advertising professionals who are members.

It is also possible to block certain third-party cookies directly via publishers:

Cookie type

Means of blocking

Analytical and performance cookies

Google Analytics

Targeted advertising cookies


The following types of cookies may be used on our websites:

Mandatory cookies

Functional cookies

Social media and advertising cookies

These cookies are needed to ensure the proper functioning of the site and cannot be disabled. They help ensure a secure connection and the basic availability of our website.

These cookies allow us to analyse site use in order to measure and optimise performance. They allow us to store your sign-in information and display the different components of our website in a more coherent way.

These cookies are used by advertising agencies such as Google and by social media sites such as LinkedIn and Facebook. Among other things, they allow pages to be shared on social media, the posting of comments, and the publication (on our site or elsewhere) of ads that reflect your centres of interest.

Our EZPublish content management system (CMS) uses CAS and PHP session cookies and the New Relic cookie for monitoring purposes (IP, response times).

These cookies are deleted at the end of the browsing session (when you log off or close your browser window)

Our EZPublish content management system (CMS) uses the XiTi cookie to measure traffic. Our service provider is AT Internet. This company stores data (IPs, date and time of access, length of the visit and pages viewed) for six months.

Our EZPublish content management system (CMS) does not use this type of cookie.

For more information about the cookies we use, contact INRA’s Data Protection Officer by email at or by post at:

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

Dernière mise à jour : Mai 2018

Menu Logo Principal CBGP Cirad IRD SupAgro Muse

Home page



Vincent Lesieur
Email: vincent.lesieur(at)
Position: postdoc, Montpellier Supagro
Topic: Biological control of the Common Sowthistle, Sonchus oleraceus
CBGP supervisors: M.S. Tixier & J.F. Martin
Dates : March 6th, 2017 – March 5th, 2020

Vincent is back for at least three years as a postdoc in a collaborative project between Montpellier SupAgro and CSIRO.

Plants that have become weeds in Australia are rarely troublesome in their native range. This is often because populations in the native range are regulated by a variety of natural enemies such as insects and pathogens that attack the seeds, leaves, stems and roots of the plant. If plants are introduced to a new country without these natural enemies, their populations can grow unchecked to the point where they become so widespread that they are regarded as weeds.

Biological control aims to reunite the weeds with their natural enemies in order to suppress their populations and curtail spread. With this context in mind, the key research question that this project aims to address is which of the many natural enemies that attack the target weeds in their native range are the most appropriate candidate biocontrol agents. The key knowledge required to best answer this question is:

  1. the taxonomy of the weed to ensure that surveys target the right species (the weed reproductive biology, level of morphological variation and utility of existing taxonomic treatment of the plant genus will determine whether or not this phase of the research is straightforward or complicated);
  2. the weed’s genetic make-up to help pinpoint the geographical source of plants that invaded the new range (to better target field surveys in the native range in order to find agents highly adapted to the weed genotypes found in the invaded range;
  3. the areas of the native range that match climatically those where the weed occurs in the invaded range (to collect candidate agents in the native range that are more likely to be adapted to the climate of the proposed destination);
  4. the type and severity of damage that the candidate agents can inflict on the weed (to identify those agents that are most likely to be effective once released in the field);
  5. the specificity of the candidate agents (to demonstrate that the candidate agents do not pose an unacceptable risk to non-target plant species).