Challenges for the Implementation of commercial inoculum of arbuscular fungi in a commercial Callet vineyard (Vitis vinifera L.)

This study explores the growing potential of vitiviniculture in Brazil’s Federal District, an emerging wine region marked by unique climatic conditions and innovative cultivation techniques.

Extensive studies have been conducted on grapevine responses to water deficit, but these responses are difficult to generalise since numerous factors can influence the response(s), including genotype, developmental stage, soil, climate, and season.

As an essential element for grapevine development and yield, nitrogen is also involved in the winemaking process and largely affects wine composition. Grape must amino nitrogen deficiency affects the alcoholic fermentation kinetics and alters the development of wine aroma precursors. It is therefore essential to control and optimize nitrogen use efficiency by the plant to guarantee suitable grape nitrogen composition at harvest. Understanding the impact of environmental conditions and cultural practices on the plant nitrogen metabolism would allow us to better orientate our technical choices with the objective of quality and sustainability (less inputs, higher efficiency). This trial focuses on the impact of crop limitation – that is a common practice in European viticulture – on nitrogen distribution in the plant and particularly on grape nitrogen composition. A wide gradient of crop load was set up in a homogeneous plot of Chasselas (Vitis vinifera) in the experimental vineyard of Agroscope, Switzerland. Dry weight and nitrogen dynamics were monitored in the roots, trunk, canopy and grapes, during two consecutive years, using a 15N-labeling method. Grape amino nitrogen content was assessed in both years, at veraison and at harvest. The close relationship between fruits and roots in the maintenance of plant nitrogen balance was highlighted. Interestingly, grape nitrogen concentration remained unchanged regardless of crop load to the detriment of the growth and nitrogen content of the roots. Meanwhile, the size and the nitrogen concentration of the canopy were not affected. Leaf gas exchange rates were reduced in response to lower yield conditions, reducing carbon and nitrogen assimilation and increasing intrinsic water use efficiency. The must amino nitrogen profiles could be discriminated as a function of crop load. These findings demonstrate the impact of plant balance on grape nitrogen composition and contribute to the improvement of predictive models and sustainable cultural practices in perennial crops.

In this video recording of the IVES science meeting 2023, Sara Bernardo (CITAB, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal) speaks about understanding vine response to Mediterranean summer stress for the development of adaptation strategies – in the kaolin case. This presentation is based on an original article accessible for free on OENO One.

Wines from different regions or AVAs have been found to have sensory differences, as these areas are typically located quite far apart and have dramatically different climates, soils and other terroir factors.