Terroir 2014 banner
IVES 9 IVES Conference Series 9 A generic method to analyze vine water deficit continuously

A generic method to analyze vine water deficit continuously

Abstract

In the context of global warming, water scarcity is becoming an increasing issue worldwide. However, the reference method to characterize vine water deficit is based on water potential measurement, which is a destructive and discontinuous method. The current climatic context emphasizes the need for more precise and more continuous vineyard water use measurements in order to optimize irrigation and vine water deficit monitoring.

Our work proposes a quantitative method to characterize vine water deficit variations in a continuous fashion. Combining sap flow and climatic raw data, the framework uses expert knowledge and mathematical modeling to characterize dry soil crop coefficient (KcB) and automatically compute a daily water deficit index Ks. As a case study we used an experimental design set in French vineyards where contrasted vine water deficit profiles were obtained by using differential irrigation treatments.

We analyzed Tr/ETref ratio variations to identify the timing and value of maximal KcB. After that preliminary step, we computed and aggregated Ks profiles for each treatment and compared irrigation effects on Ks profiles. Because sap flow and climatic sensors are installed outdoor, determination of maximal KcB value is particularly sensitive to environmental variations. As such, we studied the effect of measurement uncertainties on KcB computation and Ks profile by imposing variations in the timing and value of KcB. Implications and perspectives to improve irrigation practices are discussed.

DOI:

Publication date: August 18, 2020

Issue: Terroir 2014

Type: Article

Authors

Scholasch T. (1), Charnomordic B. (2), Hilgert N. (2)

(1) Fruition Sciences, SAS. MIBI, 672 rue du Mas de Verchant 34000 Montpellier,France 
(2) INRA-SupAgro, UMR 729 MISTEA, F-34060 Montpellier, France 

Keywords

sap flow, Ks, water use, irrigation, dry soil crop coefficient

Tags

IVES Conference Series | Terroir 2014

Citation

Related articles…

Reduced fungicide sprayings: A biodiversity boost?

Pesticides are considered one of the main causes for arthropod decline in agriculture which in turn may affect ecosystem services such as natural pest control and soil fertility.

Towards stopping pesticides: survey identification of on-farm solutions

The winegrowing sector consumes a lot of pesticides. Changes in vineyard are necessary in order to reduce or even stop using pesticides, and thus limit their harmful impacts on health and on environment. To answer these issues, the VITAE project (2021-2026) aims at designing pesticide free grapevine systems in France. For that, we take an interest in the vineyards using solutions to strongly reduce chemicals but also biopesticides. We assume that such vineyards exist and that they are implementing solutions that could inspire the design of free- pesticide system.

Research on the origin and the side effects of chitosan stabilizing properties in wine

Fungal chitosan is a polysaccharide made up of glucosamine and N-acetyl-glucosamine and derived from chitin-glucan of Aspergillus niger or Agaricus bisporus. Fungal chitosan has been authorized as an antiseptic agent in wine since 2009 (OIV) and in organic wine in 2018. At the maximum dose of 10g/hl, it was shown to eliminate Brettanomyces bruxellensis, the main spoilage agent in red wines. Fungal chitosan is highly renewable, biocompatible (ADI equivalent to sucrose) and non-allergenic. However, winemakers often prefer to use sulfites (SO2), though sulfites are classified as priority food allergens, than chitosan. Indeed, many conflicting reports exist regarding its efficiency and its side effects towards beneficial wine microorganisms or wine taste. These contradictions could be explained by the heterogeneity of the fungal chitosan lots traded, the diversity of the wines (chemical composition, winemaking process), but also, by the recently highlighted huge genetic diversity prevailing in wine microbial species.

Vitis vinifera ‘Ráthay’ on the rootstocks ‘Kober 5BB’, ‘Fercal’, and ‘3309 C’: results of a long-term field trial

Context and purpose of the study. Ráthay is an Austrian red quality wine variety with increased resistance to fungi.

Response of Shiraz/101‐14 mgt to in‐row vine spacing

Knowledge of vine reaction to plant spacing under high potential soil conditions is restricted. This study was done to determine effects of vine spacing