GiESCO 2019 banner
IVES 9 IVES Conference Series 9 GiESCO 9 Assessing macro-elements contents in vine leaves and grape berries of Vitis vinifera using near-infrared spectroscopy coupled with chemometrics

Assessing macro-elements contents in vine leaves and grape berries of Vitis vinifera using near-infrared spectroscopy coupled with chemometrics

Abstract

Context and purpose of the study – The cultivated vine (Vitis vinifera) is the main species cultivated in the world to make wine. In 2017, the world wine market represents 29 billion euros in exports, and France contributes 8.2 billion (28%) to this trade, making it a traditional market of strategic importance. Viticulture is therefore a key sector of the French agricultural economy. It is in this context that the nutritional diagnosis of the vine is of real strategic interest to winegrowers. Indeed, the fertilization of the vine is a tool for the winegrower that allows him to influence and regulate the quality of the wine. Nowadays, nutrition analysis is made with CHNS analyzer for elemental particles, and mass-spectroscopy for macro and microelements. Such methods are destructive and time consuming, then results could be obsolete for the vine grower. Near-infrared spectroscopy coupled with chemometrics tools allows to developed models of prediction that can provide accurate information about nutrition status of the vine in the field. In this study, we concentrate on the relative amount of Carbon [C], Hydrogen [H], Nitrogen [N], Sulphur [S] in dry matter (DM) and the C:N ratio.

Material and methods – 252 samples of different organs (leaves blade, leaves petioles, pea sized berries and berries at véraison) of 4 varieties (Muscat, Chasselas, Négrette and Sauvignon blanc) were analyzed. Spectrum were taken on both fresh material and dried ones with a reflectance spectrometer. The spectra were pre-processed using multiple scatter correction (MSC) and 1st and 2nd order Savitsky-Golay derivative (D1 and D2), before developing the cross-validation models using partial least square (PLS) regression and test it on a prediction set.

Results – The coefficient of determination in prediction (r²), the roots mean square error of prediction (RMSEP) and the ratio of performance of prediction (RPD) were obtained for C (0.49, 14.6% of DM and 1.33 on fresh material with MSC, 0.45, 15.4% of DM and 1.26 on dry material with MSC), H (0.56, 1.71% of DM and 1.45 on fresh material with D1, 0.49, 1.88% of DM and 1.32 on dry material with D1), N (0.91, 1.12% of DM, 3.32 on fresh material with raw spectra, 0.95, 0.84% of DM and 4.39 on dry material with MSC), S (0.47, 0.319% of DM and 1.31 on fresh material with MSC, 0.46, 0.322% of DM and 1.30 on dry material with D2) and C:N ratio (0.85, 8.20 and 2.58 on fresh material with raw spectra, 0.87, 7.55 and 2.80 on dry material with D2). Results show that the near-infrared reflectance spectroscopy can be used to assessing the level of nitrogen nutrition in vine and the C:N ratio. All model performance could be improved by increasing the number of samples.

DOI:

Publication date: March 11, 2024

Issue: GiESCO 2019

Type: Poster

Authors

Sebastien CUQ1*, Valerie LEMETTER2, Olivier GEFFROY1, Didier KLEIBER1, Cecile LEVASSEUR-GARCIA3

1 Physiologie, Pathologie et Génétique Végétales (PPGV), Université de Toulouse, INP-PURPAN, Toulouse, France
2 Plateforme TOAsT, Université de Toulouse, INP-PURPAN, Toulouse, France
3 Laboratoire de Chimie Agro-industrielle (LCA), Université de Toulouse, INRA, INPT, INP-PURPAN, Toulouse, France

Contact the author

Keywords

Infrared, Spectroscopy, Elemental analysis, Vitis vinifera

Tags

GiESCO | GiESCO 2019 | IVES Conference Series

Citation

Related articles…

Prefermentative CO2 saturation of grape must to obtaining white wines with low SO2 content

The objective this work has been study the possibility of partially or completely replacing sulphur in the winemaking of white wines through the use of the prefermentative saturation of musts with CO2.

« Wine routes »: a collective brand to build a wine reputation on the basis of terroir and landscapes

Le marché international du vin est désormais tourné vers la qualité et les vignobles de vin de masse se transforment pour construire la qualité et la réputation de leurs produits. Cette construction s’appuie notamment sur la valorisation de ressources territoriales de nature physique (terroir, pacage, écosystème) et humaine (savoir-faire, culture, patrimoine…). Les « Routes des Vins » sont des exemples concrets de ces processus de «territorialisation», combinant ces ressources territoriales pour communiquer sur l’ancrage géographique et la spécificité des vins. Les «Routes des Vins» émergentes, observées dans les régions vitivinicoles en transition vers la qualité, en Languedoc Roussillon, à Mendoza (Argentine) et au Western Cape (Afrique du Sud), participent souvent à la valorisation des terroirs, en organisant un itinéraire sur le territoire associé, en faisant découvrir les vins «de qualité», les paysages, les pratiques et le savoir-faire associés à leur élaboration.

Closure permeability modulates the aroma expression of monovarietal white wines during bottle ageing

Bottle ageing is a critical period for wine quality, as it undergoes various chemical and sensory changes during storage. Ideally, a phase of qualitative ageing, during which wine sensory quality improves, is followed by a decline of quality. Understanding how different oenological variables influence these phases is a key challenge in modern winemaking. Recent studies highlighted the significant role of oxygen in modulating reactions involving volatile and non-volatile components, impacting aroma evolution during bottle aging. Oxygen exposure of wine during bottle ageing is mediated by closure.

Biodiversity and biocontrol ability of Trichoderma natural populations in soil vineyards from Castilla y León region (Spain)

Trichoderma is a microorganism present in many agricultural soils and some of its species could be used as natural biological control agents. In this work, the presence of natural populations of Trichoderma was estimated in soil vineyard and its biocontrol capacity against Phaeoacremonium minimum, one of the main agent causals of grapevine trunk diseases instead of using pesticides. Moreover, physicochemical variables in soil such as pH, organic matter and nutrients were evaluated to determine a possible correlation to natural populations of Trichoderma.

Drought responses in Chardonnay and Sauvignon blanc grapevine cultivars: Mechanistic insights and varietal contrasts

This study explored the responses of Chardonnay and Sauvignon blanc grapevine cultivars to water deficit across four years, uncovering their shared patterns and distinctive coping mechanisms. The research was conducted in a commercial vineyard located in Isla de Maipo, Chile. Various characterization approaches were employed including plant water potentials (), gas exchange measurements, shoot vulnerability curves, productivity assessments, and leaf cell water relations. Linear mixed models and sensitivity analyses were performed using various statistical methods to evaluate cultivar responses to water deficit. As the water deficit progressed, both cultivars displayed a parallel reduction in stomatal conductance, leaf turgor, and increased shoot embolism.