Seasonal vine nutrient dynamics and distribution of shiraz grapevines

Many fleshy fruit, including the grape berry, exhibit a double‐sigmoid growth (DSG) pattern. Identification of the curious DSG habit has long been attributed to Connors’ (1919) work with peaches

L’AOC Priorat, située derrière les montagnes du pré littoral de Tarragone, se caractérise par un climat méditerranéen avec une tendance à la continentalité et très peu de précipitation pendant le cycle végétatif. Les sols sont secs, pauvres et caillouteux, formés par des schistes. Au cours des années 2000 et 2001, une étude de l’influence du terroir sur la typicité des vins du Priorat a été réalisée en prenant comme référence trois cépages cultivés dans différentes parceIles pour mesurer l’effet du terroir et du mésoclimat sur la qualité des vins:

Aim: Climate change is altering some aspects of winegrape production with an advancement of phenological stages which may endanger viticultural areas in the event of a late frost. This study aims to evaluate the potential of satellite-based remote sensing to assess the damage and the recovery time after late frost events.

Water status impact in viticulture has been widely explored, as it strongly affects grapevine physiology and grape chemical composition. It is considered as a key component of vitivinicultural terroir. Most of the studies concerning grapevine water status have focused on either physiological traits, or berry compounds, or traits involved in wine quality. Here, the response of grapevine to water availability during the ripening period is assessed through non-targeted metabolomics analysis of grape berries by ultra-high resolution mass spectrometry. The grapevine water status has been assessed during 2 consecutive years (2019 & 2020), through carbon isotope discrimination on juices from berries collected at maturity (21.5 brix approx.) for 2 Vitis vinifera cv. Pinot noir (PN) and Chardonnay (CH). A total of 220 grape juices were collected from 5 countries worldwide (Italy; Argentina; France; Germany; Portugal). Measured δ13C (‰) varied from -28.73 to -22.6 for PN, and from -28.79 to -21.67 for CH. These results also clearly revealed higher water stress for the 2020 vintage. The same grape juices have been analysed by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS) and Liquid Chromatography coupled to Mass Spectrometry (LC-qTOF-MS), leading to the detection of up to 4500 CHONS containing elemental compositions, and thus likely tens of thousands of individual compounds, which include fatty acids, organic acids, peptides, phenolics, also with high levels of glycosylation. Multivariate statistical analysis revealed that up to 160 elemental compositions, covering the whole range of detected masses (100 –1000 m/z), were significantly correlated to the observed gradients of water status. Examples of chemical markers, which are representative of these complex fingerprints, include various derivatives of the known abscisic acid (ABA), such as phaesic acid or abscisic acid glucose ester, which are significantly correlated with higher water stress, regardless of the variety. Cultivar-specific behaviours could also be identified from these fingerprints. Our results provide an unprecedented representation of the metabolic diversity, which is involved in the water status regulation at the grape level, and which could contribute to a better knowledge of the grapevine mitigation strategy in a climate change context.

La délimitation et la caractérisation des zones viticoles posent en Espagne des problèmes spécifiques non seulement dus aux caractéristiques propres au territoire mais aussi à la dimension, la distribution et l’indice d’occupation viticole dans les appellations d’origine.