Black foot disease in South African vineyards and grapevine nurseries

Alteration of sap pH is one of the first chemical changes that occurs within the xylem vessels of plants exposed to drought. Xylem sap acidification accompanied by the accumulation of soluble sugars has been recently documented in several species (Sharp and Davis, 2009; Secchi and Zwieniecki, 2016). Here, Vitis vinifera plants of the anysohydric cultivar Barbera were exposed to either short (no irrigation; SD) or to prolonged drought (continual reduction of 10% water; PD). When comparable severe stress was reached, the potted grapes were re-watered. SD was characterized by fast (2–3 days) stomatal closure and high abscisic acid (ABA) accumulation in xylem sap (>400 μg L−1) and in leaf. In PD plants, the rise in ABA levels was considerably diminished.

Le Dipartimento di Progettazione dell ‘Architettura del Politecnico di Milano et l’Istituto di Viticoltura della Facoltà d’Agraria di Piacenza dell’Università Cattolica del Sacra Cuore, ont elaboré une proposition pour réaliser, dans l’aire de colline de la province de Piacenza, un Parco Produttivo Agrovitivinicolo.

the phenological evolution is a crucial aspect of grapevine growth and development. Accurate detection of phenological stages can improve vineyard management, leading to better crop yield and quality traits. However, traditional methods of phenological tracking such as on-site observations are time-consuming and labour-intensive. This work proposes a scalable data-driven method to automatically detect key phenological stages of grapevines using satellite data. Our approach applies to vast areas because it solely relies on open and satellite data having global coverage without requiring any in-field data from weather stations or other sensors making the approach extensible to other areas.

Consumers and the wine industry tend to agree on the ability of old vines to produce fruit that allows the production of wine of superior character. However, despite past and ongoing research, objective evidence of this point of view is still debated and studies on robust, specifically dedicated plots are scarce. Thus the impact of grapevine age on berry oenological potential and wine quality remains an open question. To try to objectively address the issue, a unique vineyard was established at Geisenheim University, Germany. It was planted in 1971 with cv. Riesling grafted on 5C Teleki. In 1995 and 2012, several rows were uprooted and replanted with the same rootstock/scion combination, resulting in a vineyard with alternate rows of identical plant material, but with different planting dates. The parameters of technical maturity and grape composition at harvest were analyzed during seasons 2014, 2015, 2016 and 2017 combining HPLC and enzymatic methods. Separate micro-vinifications were made for each age group and wine composition was analyzed by a combination of 1H-NMR and SPE-GC-MS.

In Enology the conventional processes of filtration for clarification and stabilization are giving place to alternative membrane processes, including nanofiltration (NF). Furthermore, the increased alcohol content in wines recorded in recent years became an important issue for all the main wine producing countries. Among techniques available to the wine industry to reduce the ethanol content, NF is certainly one of the newest. This study is focused on the evaluation of NF influence on wine physical-chemical composition, including mineral content, which in accordance to our best knowledge is a novelty.