Impact of Japanese beetles (Popillia japonica Newman) on the chemical composition of two grape varieties grown in Italy (Nebbiolo and Erbaluce)

At least since de XIXth century, wine writers oppose quite often the wines from Gevrey-Chambertin to the wines from Chambolle-Musigny claiming that the former are more “masculine” (full-bodied, powerful tannins, leathery, rustic…) and the later more “feminine” (delicate, elegant, silky, flowery…).

La mesure de la résistivité électrique des sols est une technique non destructive, spatialement intégrante, utilisée depuis peu en viticulture. L’utilisation d’appareils de mesures performant et de logiciels adaptés permet de traiter les données afin de pouvoir visualiser en deux ou trois dimensions les variations de textures ou d’humidité d’un sol.

Alcoholic fermentation is the main step for winemaking, mainly performed by the yeast Saccharomyces cerevisiae. But other wine yeasts called non-Saccharomyces may contribute to alcoholic fermentation and modulate the wine aroma complexity. The recurrent problem with the use of these non-Saccharomyces yeasts is their trend to die off prematurely during alcoholic fermentation, leading to a lack of their interesting aromatic properties searched in the desired wine. This phenomenon appears to be mainly due to interactions with S. cerevisiae. These interactions are often negatives but remain unclear because of the species and strain specific response. Among the non-Saccharomyces yeasts, Lachancea thermotolerans is a wine yeast naturally found in grape must and well known as a great L-lactic acid producer and an aromatic molecules enhancer, but its behavior during alcoholic fermentation can be completely different in co-fermentation with S. cerevisiae in function of strain used.

In the context of increasingly hot and dry summers, the adoption of innovative irrigation technologies has become essential for maintaining grape production while minimizing water use.

Elemental composition, measured as the concentrations of different elements present in a given tissue at a given time point, is a key indicator of vine health and development. While elemental composition and other high-throughput phenotyping approaches yield tremendous insight into the growth, physiology, and health of vines, costs and labor associated with repeated measures over time can be cost-prohibitive. Recent advances in handheld sensors that measure hyperspectral reflectance patterns of leaf tissue may serve as an affordable proxy for other types of phenotypic data, including elemental composition. Here, we ask if reflectance patterns of dried Chambourcin leaf tissue from an experimental grafting vineyard can predict the known elemental composition of those leaves.