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 Agrocampus Ouest Rennes 1 University Logo Igepp

Home page

Nouhaud Pierre

Genomics of host-plant adaptation in the pea aphid complex

PhD defended decembre 19th, 2014
Direction: Jean-Christophe Simon & Solenn Stoeckel


Natural selection is an evolutionary force that exerts a sorting of individuals based on their
phenotypes and their fitness. Its main consequence is the adaptation of living organisms to their
environment. Understanding by which mechanisms these organisms adapt to environmental
changes is a central goal in evolutionary biology with various applications including human health,
ecosystem protection or food production. Phytophagous insects represent valuable models in the
study of the adaptive process as they usually display high host plant specificity. The pea aphid
Acyrthosiphon pisum presents genetically differentiated and specialized sympatric biotypes
feeding on several wild and cultivated legume species. This work sought to identify genomic
regions involved in host plant adaptation in the pea aphid complex by performing genome scans
between distinct biotypes. These methods rely on the analysis of patterns of genetic polymorphism
to identify the molecular signatures of selection in the genomes and ultimately pinpoint genes
putatively involved in the adaptive process. Using such genome scan approaches, we identified a
small number of genes that could play a role in trophic adaptation. Some of these genes are
involved in the chemosensory system and in the salivary system, two functions respectively
involved in host choice and plant use. This work represents a very first step in the genomic study
of adaptation in the pea aphid complex and our study pave the way for functional genomics
analyses to validate the role of these candidate genes in preferential host plant use. Our work will
ultimately help to better understand the influence of adaptive divergence on the diversification of
phytophageous insects.