Xylem vessel blockages in grape pedicel growing in tropical climate observed by microtomography

Downy mildew is one of the most important grapevine diseases, caused by the Oomycete Plasmopara viticola. The management of the disease in organic agriculture can require up to 15 copper applications per year. However, copper accumulates in the soil, is phytotoxic and is toxic for organisms living in the soil, its use has been restricted in European Union to maximum 28 kg in 7 years. Therefore, testing of alternatives with equal effectiveness is desirable. Among those, the natural biopolymer chitosan, obtained from crab shells, proved to be effective toward downy mildew in plot experiments. The aim of our trials was to extend chitosan applications in large scale experiments in different years, cultivars and environmental conditions.

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.

At a time when the world’s winegrowing industry is having to adapt to a number of challenges, winegrowers are wondering about the consequent changes they will have to make (grape varieties, changes in vineyard and cellar techniques). For winegrowers and consumers alike, there is also the question of how these changes will affect the taste of their wines. This research, based on the study of numerous sources and archives from the 20th century, some of which have never been published before, aims to show that, in the recent past, the winegrowing world has shown incredible resilience in the face of crises, and that the taste and perception of fine wines has changed considerably in 100 years.

The wine sector is greatly threatened by climate change, but is also one of its contributors.

The aim of this paper is to analyse the impact of landscapes in the notoriety and marketing of wines and in tourism promotion, specifically in the case of two centenary Portuguese demarcated regions