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 Logo Principal Institut Agro Montpellier LEPSE membre de Montpellier Université d'Excellence Labex AGRO Institut Carnot DigitAg

Home page

Westgeest Adrianus J (Adriaan)

Westgeest Adrianus J (Adriaan)
PhD student

Thesis defended on 18.12.2020

Topic: "Determinants of night transpiration and its effects on water use efficiency in grapes"

Abstract :

Viticulture covers a large part of the arable land in the Mediterranean regions. However, the maintenance of this emblematic crop in drought-prone environments is threatened by climate change. Exploring large genetic collections can help select more water-efficient cultivars. Stomata, tiny pores on the leaf epidermis bounded by guard cells that can open and close, play an essential role in this process as they regulate gas exchange - photosynthesis and transpiration - between the plant and the atmosphere. Due to stomatal behaviour, increased photosynthesis usually coincides with increased transpiration. Thus, reducing night transpiration appears to be a promising breeding strategy to reduce water loss without penalising photosynthesis. However, day and night transpiration are correlated to some extent. Here, we explored the genetic and physiological basis of the daily (24 h) dynamics of transpiration in grapevine (Vitis vinifera). A protocol was developed for high-throughput phenotyping of transpiration dynamics in detached leaves. This allowed genome-wide association studies (GWAS) to be carried out on a diversity panel of 279 cultivars, which generated candidate genes that were then studied using different approaches. Quantitative genetic analyses revealed several single nucleotide polymorphisms (SNPs) associated with different aspects of transpiration dynamics. In particular, we found an association for nocturnal transpiration that co-located with the abundance of recumbent trichomes and cuticular striae on the leaf epidermis. A MYB transcription factor was identified as a strong candidate involved in the production of both structures, showing a complex interaction with stomatal development. Based on genomic and coexpression analyses, we propose a new model of interacting genes involved in the development of epidermal structures and impacting on night transpiration. Unexpectedly, we also found an association for daytime transpiration close to a gene essential for nocturnal starch metabolism. The corresponding mutant in Arabidopsis thaliana was impaired in stomatal light opening and endogenous nighttime reopening. Comparison with other mutants in the pathway revealed that the role of this gene in the control of stomatal movements extends beyond starch metabolism. Its cell-autonomous action was studied, with equivocal conclusions. Overall, this work provided several interesting targets for night-time water saving and water use efficiency in grapevines.

Financing :

50% INRAE, 50% Région Occitanie

Jury :

Thierry SIMONNEAU - thesis director - research director - INRAE Montpellier
Cathie MARTIN - rapporteur - professor - University of East Anglia
Didier LE THIEC - rapporteur - director of research - INRAE Nancy
Elisa MARGUERIT - examiner - lecturer - Bordeaux Sciences Agro
Benoît  LACOMBE - examiner - research officer - CNRS
Florent PANTIN - thesis co-supervisor - lecturer - Institut Agro - Montpellier SupAgro