Using image analysis for assessing downy mildew severity in grapevine

Agriculture faces many global warming challenges especially in the Mediterranean region. Many strategies have been proposed in viticulture to manage global warming. Rootstocks are among them since they may affect water uptake and the scion’s performance.
The study conducted in La Rioja, Spain, aimed to investigate the impact of different rootstocks (1103P and 161-49C) on the performance of the Tempranillo grapevine scion over a three-day cycles under drought and extreme conditions, specifically during a heatwave in July 2022, with maximum air temperatures up to 40ºC and average daily temperatures of 29.1ºC.

Foreseeing climatic changes, the abnormally hot and dry year of 2005 can be revealer of some varieties behavior in different climatic conditions.

Nitrogen (N) supply strongly influences vine productivity and berry composition, matching availability and uptake requirements of vines during the growing season is essential to optimize vine nutrition. The nutritional status of grapevines is commonly assessed by the determination of petiole nutrient concentrations at flowering. The reserve N could also be an earlier indicator for grapevine N status, this work aimed to assess how the petiole levels relate to these perennial N reserves.

Climate change will increase the frequency of water deficit situation in some European regions, by the increase of the evapotranspiration and the reduction of rainfalls during the growing cycle. This requires finding ways of adaptation, including the use of plant material which is more tolerant to drought. In addition to the varieties used as scions that result in the typicality of wines, rootstocks constitute a relevant way of adaptation to more stressful environmental conditions.

The increase in air temperature that is occurring in many important wine-growing areas around the world is resulting in the decoupling between the phenolic and the technological maturity of grapevine berries. This new ripening pattern leads to the production of light-bodied high alcoholic wines, but this is in countertendency with the increasing consumers’ demand for wines with low-to-mid alcohol concentrations. The oenological techniques proposed to reduce wine alcohol content are often very expensive and lead to detrimental effects on wine quality. Many viticultural practices have been proposed to slow down sugar accumulation the berry. One possible strategy that was previously found to be suitable for Aglianico grapevine is post-veraison shoot trimming. The aim of this work was to assess the carry over effects on the following year of shoot trimming and vine water status on yield and total soluble solids because the expected reduction in vine fertility could lead to a reduction in the effectiveness of shoot trimming.