Thibaut Scholasch

• PhD
• Researcher at Fruition sciences

UNION GIRONDINE DES VINS DE BORDEAUX-JUILLET-AOÛT 2023 C ette brève revue vise à fournir une perspective actualisée des résultats de la littérature comparant les différentes méthodes basées sur la plante. Les avancées scientifiques concernant la régulation hydrique de la vigne sont dé-crites et appliquées afin de discuter des forces et des limites...

Assessing vine water status is crucial to optimising cultural practices, including irrigation strategies, to guarantee environmentally and economically sustainable viticulture in a context of increasing water shortages and global warming. Vine water status can be assessed indirectly, via soil-based or atmospheric-based methods, or directly via plan...

Climate influence on grapevine physiology is prevalent and this influence is expected to increase with climate change. Climate influence on grapevine physiology can vary depending on the terroir. A better understanding of these local terroir variations is likely to be achieved with analyses that use local data; i.e., farm/vineyard data. Thus, the c...

Grapevine yield is defined as the quantity of harvest, expressed as either grape mass or wine volumeunits, which has been collected per surface unit are and per crop cycle. The information about current and future yield, termed a yield assessment in this paper, is an essential decision-making element for the grape and wine industry. Crop management...

Assessing the water status of the vine is crucial for optimizing cultivation practices and irrigation strategies while ensuring environmentally and economically sustainable viticulture. In view of the most recent results in the literature, this article critically reviews the main measurement methods carried out directly on plants.

L'évaluation de l'état hydrique de la vigne est cruciale pour optimiser les pratiques culturales et les stratégies d'irrigation afin de garantir une viticulture durable sur le plan environnemental et économique, compte tenu des pénuries d'eau croissantes causées par le réchauffement climatique. L'état hydrique de la vigne peut être évalué par des m...

Rising global air temperatures will lead to an increased evapotranspiration and altered precipitation pattern. In many regions this may result in a negative water balance during the vegetative cycle, which can augment the risk of drought and will require mitigation strategies. These strategies, ultimately, will mean the installation of irrigation s...

The increasing risk of water deficit stress due to global warming subjects winegrowers of traditional rain fed viticulture regions to new challenges regarding vine water status assessment and possible drought mitigation strategies, such as irrigation. This review summarizes the most recent studies on the impact of water deficit stress on vine and b...

The Fullerton Sap flow meeting presented lots of scientific evidence showing how useful sap flow measurements could be for application in horticulture. For the past 10 years, our company, Fruition Sciences has been using real time sap flow data to improve irrigation scheduling across many vineyard regions worldwide. However, despite its solid scien...

Plant water status is one of the main factors affecting yield and quality in viticulture. Nevertheless, it is generally difficult to characterize it with enough precision for management purposes. In addition to its temporal variation, related to climate conditions, it has been shown that it is also spatially variable within the vineyard. In practic...

Grapevines are crops of global economic importance that will face increasing drought stress because many varieties are described as highly sensitive to hydraulic failure as frequency and intensity of summer drought increase. We developed and used novel approaches to define water stress thresholds for preventing hydraulic failure, which were compare...

Des travaux récents ont mis en avant une importante variabilité de concentration en rotundone - le principal composé responsable de l'arôme poivré des vins rouges - au sein d'une même parcelle, en lien avec les caractéristiques du sol et le niveau de contrainte hydrique. Afin de développer une méthode pour cartographier de manière indirecte et simp...

effect of physiological trajectories on flavonoids extractiblity

Recent research works highlighted large variability in rotundone concentration - the main compound responsible for peppery aroma in red wines - within a vineyard block associated with variation in land underlying the vineyard and vine water deficit. In order to further study and determine practical ways to map rotundone spatial variability, a study...

This work proposes a methodology using temporal data and domain knowledge in ord er to analyze a complex agronomical feature, namely the influence of vine water deficit on grape quality. Raw temporal data are available but they are not direc tly usable to estimate vine water deficit. The methodology associates advanced t echniques in computer scien...

This work proposes a framework using temporal data and domain knowledge in order to analyze complex agronomical features. The expertise is first formalized in an ontology, under the form of concepts and relationships between them, and then used in conjunction with raw data and mathematical models to design a software sensor. Next the software senso...

Vine water status is a major parameter for vine management because it affects both wine quality and yield. In order to optimize vineyard management and harvesting practices, it is necessary to characterize vineyard water status spatial variability. This work aims at establishing an empirical spatial model for stem water potential (ΨStem) with ancil...

Aims: Various types of data are likely to be used in a precision viticulture framework, to adjust management actions according to within field variations. This paper proposes an alternative way of analysis to classical methods. Methods and Results: Data are analysed using fuzzy logic techniques. The result is a set of linguistic fuzzy rules induced...

Airborne multispectral image data were compared with intercepted photosynthetic photon flux (PPF) in commercial winegrape (Vitis vinifera) vineyards of Napa Valley, Calif. An empirically based calibration was applied to transform raw image pixel values to surface reflectance. Reflectance data from the red and near-infrared spectral regions were com...

Advanced computing technologies are being developed to combine remotely sensed imagery with ancillary data for production of ecological and agricultural "nowcasts" and forecasts. NASA's Terrestrial Observation & Prediction System (TOPS) uses Earth-viewing satellite imagery to generate data fields related to hydrology, meteorology and ecosystem stru...

Stem Water Potential (SWP) is extensively used to manage irrigation scheduling. With California Cabernet-Sauvignon vineyard, taken as study field, the aim of this paper is to determine whether this indicator is really appropriate for this purpose. First the relationship between SWP and soil moisture is carefully studied. A novel method based on wat...

Normalized difference vegetation index (NDVI) data, acquired at two-meter resolution by an airborne ADAR System 5500, were compared with fraction of photosynthetically active radiation (FPAR) absorbed by commercial vineyards in Napa Valley, California. An empirical line correction was used to transform image digital counts to surface reflectance. "...