Jun 23, 2023 | GiESCO 2023, IVES Conference Series, Technical sessions
Cabernet Sauvignon is the top red wine cultivar in CA, however, the hot climate in Fresno is not ideal for Cabernet Sauvignon, particularly for berry color development. Fruit-zone leaf removal and irrigation were studied previously to have the significant effect on grape yield performance and berry quality. But the timing of leaf removal and the timing of irrigation are still inconclusive. Also, mechanical fruit-zone leaf removal is relatively new in CA. Our study aims to identify the interactive effect of mechanical fruit-zone leaf removal and irrigation on Cabernet Sauvignon’s yield performance and fruit quality and find the ideal timing of leaf removal and irrigation to maximize the berry color while maintaining the sustainable yield level.
Jun 23, 2023 | GiESCO 2023, IVES Conference Series, Technical sessions
Grapevine leaf removal (LR) in the cluster area is typically done between fruit set and cluster closure to create an unfavorable microclimate for fungal diseases, such as Botrytis cinerea and powdery mildew. Grape growers are now turning their attention to pre-flowering LR, which has additional benefits under certain conditions. When applied before flowering, LR strongly affects fruit set and thus the number of berries per cluster. It is therefore a good yield control tool, replacing time-consuming manual cluster thinning (Poni et al. 2006). It also improves berry structure, that is, skin thickness, skin-to-pulp ratio, and berry composition (total soluble solids, titratable acidity, and polyphenols) (Palliotti et al. 2012; Komm and Moyer 2015). By exacerbating competition for assimilates between reproductive and vegetative organs, pre-flowering LR also poses some risks. Excessive yield loss at the same year’s harvest due to a too low fruit set rate is the main concern: intensive pre-flowering LR (100% of the cluster area) can induce up to 50% yield loss in potted vines (Poni et al. 2005). Other parameters, such as cool climatic conditions during flowering, also affect fruit set rate and make it difficult to predict potential yield at harvest. Repeated and overly intensive preflowering LR can have repercussions over time and induce a decline in bud fruiting and plant vigor (Risco et al. 2014).
Jun 23, 2023 | GiESCO 2023, IVES Conference Series, Technical sessions
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.
Jun 23, 2023 | GiESCO 2023, IVES Conference Series, Technical sessions
In the pursuit of increasing sustainability, climate change resiliency and independence of synthetic pesticides in agriculture, the interest of consumers and producers in organic and biodynamic farming is steadily increasing. This is in particular the case for the vitivinicultural industry in Europe, where more and more producers are converting from organic to biodynamic farming. However, clear scientific evidence showing that biodynamic farming improves vine physiology, vine stress resilience, berry or wine quality, or is more sustainable for the environment is still lacking although this issue has been addressed by several research teams worldwide.
Jun 23, 2023 | GiESCO 2023, IVES Conference Series, Technical sessions
Soil management through cover crops in the lines of the vineyards is a common practice in viticulture, since it improves the characteristics of the soil. It has been shown that the cover crops can influence the cycle of nutrients, promote infiltration, decrease erosion, and enhance the soil microbiota biodiversity improving the grapevines. However, the area under the vines tends to be left bare by applying herbicides or tillage to avoid competition with the crop in hot climates. The use of cover crops under the vines might be a plausible alternative to the use of herbicides or cultivation, improving grapevine quality and soil characteristics. The aim of this research was to study the implications of different management of the soil under the vines (herbicide, cultivation or cover crops) on grapevine growth, water and nutritional status and belowground microbial communities.
