Influence of spraying of copper fungicides on physiological parameters of Vitis vinifera L. Cv. ‘Merlot’

Climate change is increasing the frequency and severity of environmental hazards (e.g., prolonged drought), and even non-extreme climate events (e.g., a period of slightly warmer temperatures) can lead to extreme impacts when they occur simultaneously with other (non-extreme) events.

Effervescence and foaming properties are the main visual characteristics assessed by the consumer during
sparkling wine tasting.

The brown marmorated stink bug (BMSB, Halyomorpha halys Stal) is an invasive pentatomid native to eastern Asia that is spreading rapidly worldwide, notably through human-mediated activities. Globally, it was reported in the USA, Canada, Italy, Hungary, and other European countries. BMSB has a broad host range that includes over 170 plants, many of agricultural importance, including various fruit, vegetables, row crops, and ornamentals. When present in the vineyard, the pest can affect yield and quality by directly feeding on berries resulting in fruit collapse and necrosis. Additional damage occurs when BMSB are carried into the winery within the grape clusters. The presence of BMSB during wine processing can affect juice and wine quality through the release of volatile compounds produced as a stress response. The major secretes compounds are tridecane and trans-2-decenal. Tridecane is an odorless compound and its effect on wine quality is currently unknown. Trans-2-decenal is an unsaturated aldehyde considered to be the main component of BMSB taint with strong green, coriander, and musty-like aromas. Its threshold value in wine was estimated at about 5 µg/L.

Vitis vinifera L. and other Vitis have high genetic variations for cultivars or varieties. Many countries carried out strong efforts creating new clones of varieties, mainly focusing on plants free of viruses and other grapevine diseases, but also on different agronomical and enological characteristics of the plants. The aim of this study was to evaluate six clones of Merlot in the traditional viticulture of southeastern Brazil, focusing on distinct characteristics of yield, enological potential of grapes and wine typicality, in order to improve wine quality.

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.