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 logo remix UE.Logo

ReMIX H2020 - Intercrops

The ‘four Cs’ in action - competition, complementarity, cooperation and compensation, evaluated in WP2

By Erik Steen Jensen

Research is initiated to determine the role of the four Cs in leading to “over-yielding” of intercrops compared to sole crops by using a long-term experiment with maize and fababean grown at different levels of N and P fertilizers in China Agricultural University.

“Overyielding” means that the intercrop has a significant higher yield than expected from the species composition as compared to how the species perform in sole crops. In addition, theoretical work is initiated by INRA on determining the critical N concentration of intercrops.

Field experiments for determining interactions in species mixtures for improved yield and yield stabilisation

New field experiments have been successfully carried out at the Aristotle University of Thessaloniki (AUTH, Greece), including pea-wheat mixtures (several varieties of each tested), and with/without irrigation, to further study how species mixtures interact for improved acquisition of light and water under different managements.

intercropping wp2 1

Field experiment in Greece on wheat-pea intercropping  (@Christos Dordas, AUTH)

Field experiments at the Swedish University of Agricultural Sciences (SLU) and University of Hohenheim (UHOH) have been established during the first year to determine how intercrops and sole crops of pea and oats perform in a field with heterogeneous soil conditions. The sole crops and intercrops were sown in strips along transects with known soil variability within the field.

intercropping wp2 2

Field experiment at University of Hohenheim 2018 (@ J. Zachmann, UHO)

The growth season in southern Sweden resulted in severe drought stress of the pea and oat crops resulting in no harvestable pea in sole and intercrop, but the oat yield in the intercrop was about 80% of the sole crop yield indicating the compensation principle of intercropping when one of the component crop is failing due to abiotic stress. The field experiment in UHOH was successful and is currently analysis is being carried out as are new a method to use remote sensing to determine the proportions of species in intercrops with drones.

Modelling above- and below-ground plant interactions in species mixtures

A review article by Noemi Gaudi and 20 co-authors on existing models for annual crop mixtures was published in Agronomy for Sustainable Development vol. 39, April 2019: “Current knowledge and future research opportunities for modeling annual crop mixtures. A review”. It highlights that modelling of annual crop mixtures is in its infancy and gives to model users some important keys to choose the model based on the questions they want to answer, with awareness of the strengths and weaknesses of each of the modelling approaches. Future models will have to simulate impacts of annual crop mixtures on various ecosystem services and the field scale should be included in more integrated scales such as the rotation and the agricultural landscape, including long-term effects.