Somatic embryogenesis and polyploidy in grapevine: morphological shoot and leaf traits variations

Esca is one of the major grapevine trunk diseases that cause vineyards decline and important economic losses in vineyards.

The tartaric stabilization of wines before bottling to avoid the precipitation of tartaric acid salts is an important and common step during wine production. The presence of precipitated salt crystals in bottle wines is detrimental for their quality and even a legal issue in some countries. Cold stabilization is the most common stabilization treatment. Although it has been shown to be effective, it has some significant disadvantages, mainly regarding losses of color and aromas and its high cost. Therefore, other products and methodologies are being introduced in the wineries for the replacement of this process. Some of these new techniques involve the reduction of the ions causing the insolubilization of tartaric acid while other are based in the formation of protective colloids or the inhibition of the crystallization of salts. In this study, white, rosé and red wines have been treated with carboxymethylcellulose, potassium polyaspartate and an ion exchange resin. The tartaric stability of the wines, together with the oenological, chromatic and sensory characteristics were studied after the wines had been stored during one year in the bottle. The results indicate that the use of carboxymethyl cellulose and potassium polyaspartate maintained the best the sensory and chromatic characteristics and the wine stability of the wines in comparison with an untreated control wine.

Depuis 1973, une commission statutaire administre la législation qui régit le zonage vitivinicole en Afrique du Sud. La province «Le Cap de l’ouest» cerne toutes les zones viticoles sauf quatre unités. Pour la plupart, le Cap de l’ouest a un climat méditerranéen. Les zones viticoles – qui produisent les «vins d’origine» – sont des régions, des districts, des quartiers et des domaines. Les régions sont vastes, séparées par la topographie, par ex. des chaînes de montagnes et des fleuves. Généralement, chaque région représente une zone climatique. Le climat de chaque district est plus homogène. Les quartiers sont exactement délimités par le climat, la topographie et la géologie. Les domaines sont les plus petits. Chaque domaine doit avoir un seul propriétaire.

The need to classify the vineyards of an area according to the quality of its wines is not recent, but it is only in the last ten years that studies on the suitability of different areas for the cultivation of vineyard take on an integrated and interdisciplinary character (Boselli, 1991). The definition of the suitability of the environment is thus obtained by making the climatic, pedological, topographical and cultural information interact with the vegetative, productive and qualitative expression of the grape varieties.

Performing accurate vineyard yield estimation is of upmost importance as it provides important benefits to the whole vine and wine industry. Recently, image-analysis approaches have been explored to address this issue however this approach has as main challenge the bunch occlusion, mostly by vegetation but also by neighboring bunches. The present work aims at assessing the magnitude of bunch occlusion by neighboring bunches and to evaluate its dependency on a selection of vegetative and reproductive vine parameters assessed at fruiting zone. Forty vine segments (1 m) of two vineyard plots of the white cultivars ‘Alvarinho’ and ‘Arinto’ were assessed for vegetative and reproductive features at fruiting zone and imaged with a 2D camera.