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A hyperspectral imaging database was collected on two hundred and five grape plant leaves. Leaves were measured with a hyperspectral camera in the visible/near infrared spectral range under controlled conditions. This dataset contains hyperspectral acquisition of grape leaves of seven different varieties. For each variety, acquisitions were performed on healthy leaves and leaves with foliar symptoms caused by different grapevine diseases showing clear symptoms of biotic or abiotic stress on other organs. For each leaf, chemical measurements such as chlorophyll and flavonol contents were also performed.

In the dataset presented in this article, two hundred and seventy four trays containing one hundred berries were measured by a hyperspectral camera in the visible/near-infrared spectral domain. This dataset was formed to study the use of hyperspectral imaging for maturity monitoring of grape berries [2]. This dataset contains reflectance spectra from hyperspectral camera of grape berries of three different varieties and chemical composition (sugar content).

Visible and near infrared spectroscopy (VIS-NIR) is increasingly being transferred from laboratory to industry for in-line and portable applications in various domains. By intensively using VIS-NIR spectroscopy, some abnormal observations may certainly arise. It is then important to properly handle outliers to elaborate effective prediction models. The objective of this study is to investigate the potential of using a robust method called Roboost-PLSR to improve prediction model performances for a viticulture application. This work focuses on a case study to predict sugar content in grape berries of three different grape varieties of Vitis Vinifera in a maturity monitoring context. Hyperspectral images were acquired of grape berries of Syrah, Fer-Servadou and Mauzac varieties. Reference measurements of sugar levels were made in the laboratory by densimetric baths. Performances of RoBoost-PLSR models were compared to performances of reference models using Partial Least Square Regression (PLSR). Reference prediction criteria using PLSR were obtained for all varieties with these following values: Syrah (R(2)p = 0.971; RMSEp = 5.36 g/L), Fer-servadou (R(2)p = 0.788; RMSEp = 11.69 g/L) and Mauzac (R(2)p = 0.690; RMSEp = 15.61 g/L). Prediction qualities are improved with RoBoost-PLSR: Syrah (R(2)p = 0.990; RMSEp = 3.14 g/L), FerServadou (R(2)p = 0.848; RMSEp = 10.20 g/L) and Mauzac (R(2)p = 0.927; RMSEp = 7.58 g/L). Results confirm that Roboost-PLSR method allows a better consideration of outliers within the calibration set.

Since the early 1990s, grapevine trunk diseases (GTDs) have posed threats for viticulture. Esca complex, Eutypa- and Botryosphaeria- diebacks, mostly detected in adult vineyards, are currently responsible for considerable economic losses in the main vine-growing areas of the world. Other GTDs, such as Petri- (Esca complex) and Black-foot diseases, are emerging problems in grapevine nurseries (resulting in grafting failures and/or loss of saleable plants) and in young vineyards. The impacts of GTDs in modern viticulture depend on several factors, some related to their complexity, and others linked to host plant characteristics, changes in vineyard management and to the scarcity of simple tools for their control. For these reasons control of GTDs remains difficult, also depending on knowledge transfer from research to field and vice versa . This paper outlines the main preventive and curative techniques currently applied, scientifically tested or not that have resulted from the outcomes of “Winetwork”, a European Union funded project with special emphasis on the promising and innovative approaches.

For better benefits and yields, a good estimation of the quantity of grapes in a vineyard is necessary. In this paper, a three-dimensional (3D) imagery technique using conventional 24 GHz frequency-modulated continuous- wave (FMCW) radar is applied for detecting and remotely estimating the intra-parcel quantity of grapes. An estimation is possible even in the presence of natural or artificial clutters such as leaves, wood, or irrigation hoses. The microwave sensing is performed from the radar beam scanning of a vineyard, and an estimator is defined to derive the quantity of grapes in grapevines from the radar echoes distribution in the interrogated 3D scene. An algorithm based on contour detection is applied to the 3D radar image and a new parameter, called the spread factor, is defined for classifying the echo levels of grapes. The quantity of grapes is finally deduced from an appropriate estimator. This remote sensing approach brings a new and flexible solution for precision viticulture by estimating the grape quantity even for grapes hidden by leaves.

Rotundone, the compound responsible for peppery aroma in red wines is positively correlated with the absence of water deficit during ripening which can make it problematic to produce red wines combining both superior concentrations in rotundone and phenolic compounds. To reach, this double objective, on-vine drying with cutting of the fruit bearing cane or "Passerillage Eclaircissage sur Souche" (PES), a technique that consists in cutting the cane 2-3 weeks prior to harvest on a Guyot-trained vineyard was investigated combined or not with irrigation. We showed that PES had a limited impact on rotundone in wine. As the PES technique leads to an interruption of the sap flow, our results suggest that rotundone is synthesized in the berries and not translocated. A viticultural system combining irrigation and then PES induced significant gains in rotundone, in sugar concentration, in anthocyanins and in Total Phenolic Index in wine, and in skin to juice ratio. Measurements of bunch surface temperature indicate that the enhancement of totundone production induced by irrigation is likely to be due to a direct rather than to an indirect effect through an increase in leaf area leading to a cooler bunch microclimate. (C) 2016 Elsevier B.V. All rights reserved.

Flavescence doree (FD) is a grapevine disease that spreads epidemically if not managed properly and implementation of control strategies is mandatory in most European winegrowing regions. Overall accepted strategies applied in FD management are based on vector monitoring, insecticide application and removal of infected vines and secondary hosts. Grapevine trunk diseases (GTD) involve a large number of xylem-inhabiting fungal species predominantly associated to botryosphaeria dieback, esca and eutypa dieback. Control strategies for GTD management are based on preventive techniques that minimize new infections. Both FD and GTD cause significant economic losses in European vineyards. Innovative practices and good management practices developed by scientists and winegrowers need to be disseminated and adapted to regular control strategies to maintain vineyard sustainability. Project WINETWORK is developing the innovation-driven methodology, which promotes the exchange of knowledge between science and practice. This network is implemented in ten winegrowing regions, within seven European countries. The methodology is built on a network of winegrowers and regional experts gathered in regional Technical Working Groups, Scientific Working Groups (one for each disease), and regional Facilitator Agents that stimulate their interaction. Bottom-up approach applied in WINETWORK includes surveys, conducted and synthesised by Facilitator Agents, to identify winegrower’s innovative practices, while scientists revise scientific data and adapt it to dissemination and practical use. Dissemination is adapted to different stakeholders and includes a summary of relevant practical and scientific knowledge available through the knowledge reservoir, newsletters, workshops, video clips, technical presentations, multimedia tools, etc. Overall objective of WINETWORK is to foster the exchange of scientific and practical knowledge to increase the productivity and sustainability of the sector and identify needs from the field and innovative solutions for future research agenda.

u Experimental site and design: The experimental site consisted of four consecutive rows, each row planted with one of the four certified clones of Duras N (554, 555, 627 and 654). For each clone, measurements were replicated on three experimental units of twelve continuous vines per row u Homogeneity control of the plot: Controls carried out on the plot using i) trunk circumference, a variable correlated to rotundone (1), ii) δ13C measured on grapes at harvest, and iii) NDVI mapping confirmed the absence of variability, especially between the rows u Measurements on vines and evaluation of powdery mildew severity: At harvest, number of clusters per vine and yield (kg/vine) were monitored Severe powdery mildew (Erysiphe necator) infections were recorded on grapes in 2014 at harvest and its severity was assessed by visually estimating the percentage of the cluster area colonized by the pathogen on 100 grape clusters within each experimental unit u Analyses: Conventional enological parameters were determined on healthy grapes and rotundone was measured in wines prepared by microvinification techniques (1-L Erlenmeyer flasks) u Statistical treatment: Analytical data were subjected to an analysis of variance (ANOVA) treatment using Xlstat software (Addinsoft, France). MATERIAL AND METHODS CERTIFIED CLONE AND POWDERY MILDEW IMPACT ROTUNDONE IN DURAS WINES

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 was carried on a 0.41 ha Duras vineyard from the South West of France under oceanic climatic influence. The smart point method was used and in order to optimize vineyard sampling, variability in vine architecture of the plot was assessed through measurements of trunk circumference (TC). On the basis of the three classes of TC obtained, six smart points made of 50 vines were positioned and followed independently over the vine growing season and winter dormancy for shoot elongation, stem water potential (Ψ stem), mineral uptake (petiole analysis and Dualex® measurements), airborne multispectral video imagery (NDVI), fruit quality, pruning wood weights (Physiocap® and manual weighing) and yields at harvest. At each smart point, rotundone was measured in wines obtained by microvinification techniques (1 L Erlenmeyer). Differences between smart points were very weak from an agronomic standpoint. However, a few plant physiological indicators (i.e. Ψ stem, Dualex® measurements) allowed discriminating vine performances. Despite this very low variability between plant and fruit measured variables (including those related to grape and wine quality but excluding TC), rotundone concentration was on average more than 50% higher in the wines from the high TC area. Thus, our data set suggests that a link exists between plant architecture (TC) and rotundone, and that TC can be used to approach rotundone spatial distribution. Our results also tend to strengthen the hypothesis that rotundone is very sensitive to fine variations of grapevine water status.

Experiments were carried out on Grenache, Carignan and Fer grapes in order to characterize the changes in nitrogen content of the musts, conventional enological parameters and aroma compounds of the wines induced by pre-fermentation heating of the grapes followed by alcoholic fermentation in liquid phase or in solid phase. In comparison to a standard vinification, we showed that a two-hour heat treatment at 70 °C induced a significant loss in several grape-derived aroma compounds (terpenols, norisoprenoids and some phenols) associated with an increase in α-terpineol, guaiacol and 2,6-dimethoxyphenol, which suggests thermal degradation. A significant increase in most of the ethyl esters, in acetates and in fatty acids were observed in wines fermented in liquid phase, together with a decrease in fusel alcohols. The substantial modification in the amino acid composition of the must seems to be a crucial element for the understanding of these changes.

Aim: Few recent studies have been investigating the effect of clone on aroma compounds. The aim of this research work was to study the impact of certified clones from Vitis vinifera L. cv. Duras N on grape quality and rotundone, a sesquiterpene responsible for peppery aroma which has been reported recently in red wines made from this cultivar. Methods and results: The experimental site consisted of four consecutive rows, each row planted with one of the four certified clones of Duras N (554, 555, 627 and 654). For each clone, measurements were replicated on three experimental units per row. Each experimental unit consisted of twelve continuous vines. Rotundone concentration was measured in wines prepared by microvinification techniques (1-L Erlenmeyer flasks). For both vintages of study, rotundone concentrations were significantly higher in wines from clones 554 and 654 in comparison with clone 555, while clone 627 showed an intermediate level. In 2014, differences in powdery mildew (PM) severity on clusters were identified between the four clones and a positive logarithmic correlation (r2 = 0.58) was reported on the experimental site between rotundone in wines and PM severity on grapes. Conclusion: Our results found differences in rotundone concentrations in wines made from the four Duras N certified clones. The results also suggested that grapevine defence response to PM could enhance rotundone production in berries. Clonal differences in susceptibility to biotic stress, such as PM, might explain the differences observed in rotundone concentrations between the four studied clones. Significance and impact of the study: Our results may assist grape growers to produce high quality wines with a desired aroma attribute made from Duras N. One should consider planting clone 554 in order to promote high levels of rotundone in wines made from this cultivar.