 IVES 9 IVES Conference Series 9 Macrowine 9 Macrowine 2021 9 Grapevine diversity and viticultural practices for sustainable grape growing 9 Influence of early leaf removal on the yield and composition of the grape of three white varieties in the D.O.Ca.Rioja (Spain)

Influence of early leaf removal on the yield and composition of the grape of three white varieties in the D.O.Ca.Rioja (Spain)

Abstract

AIM: Defoliation is one of the green operations more used in viticulture, whose results can be very different depending on the variety and the moment of realization. Early leaf removal consists of the elimination of basal leaves on the shoots around pre-bloom stage, which limits fruit set and initial growth of the berry, leading to less compact clusters and less weight [1]. This practice allows to control the yield, improve the sanitary state and consequently the quality of the grape [2]. The objective of this research was to evaluate the influence of early leaf removal on the yield and composition in the grape of three white varieties: Tempranillo Blanco, Maturana Blanca and Garnacha Blanca.

METHODS: This study was conducted during the 2019 season, in a vineyard located in the D.O.Ca. Rioja (Spain). At the moment of harvest, the influence of early leaf removal on different yield components (unit production, number of bunches per vine, bunch weight, weight of 100 berries and number of berries per bunch) was determined. Prior to the harvest, 500 berries were sampled for each repetition and the must was extracted. Musts were physicochemically characterized by determining probable alcohol, pH, total acidity, tartaric acid, malic acid, potassium and total polyphenols.

RESULTS: The results obtained showed notable varietal differences. The early leaf removal gave rise to a decrease in the yield components, which only were significant in Tempranillo Blanco for the unit production, bunch weight and number of berries per bunch. Also, the effects of leaf removal on the composition of the grape were higher in Tempranillo Blanco. The total polyphenol content increased significantly in the three varieties. Maturana Blanca presented a significant rise in total acidity. On the contrary, Tempranillo Blanco showed a significant decrease, significantly increasing the pH and potassium. The probable alcohol showed a significant increase in Tempranillo Blanco and Garnacha Blanca.

CONCLUSIONS

To conclude, the influence of early leaf removal on the yield and composition of the grape is variable depending on the variety.

DOI:

Publication date: September 2, 2021

Issue: Macrowine 2021

Type: Article

Authors

Laura, Alti-Palacios

Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja, CSIC, Universidad de La Rioja),Sara, GARCÍA, Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja, CSIC, Universidad de La Rioja) Juana, MARTÍNEZ, Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja, CSIC, Universidad de La Rioja)

Contact the author

Keywords

early leaf removal, yield components, chemical composition, white grape

Citation

Microwaves, an auxiliary tool to improve red wine quality in warm climates

AIM Current winery efforts in Spanish warm climate regions, as Andalusia, are aimed at red wine production in spite of sub-optimal climatological conditions

Effect of post-harvest ozone treatments on the skin phenolic composition and extractability of red winegrapes cv Nebbiolo and Barbera

Wine industry is looking forward for innovative, safe and eco-friendly antimicrobial products allowing the reduction of chemical treatments in the grape defense and the winemaking process that can affect negatively the quality of the product. Ozone has been tested in food industry giving good results in preventing fungi and bacteria growth on a wide spectrum of vegetables and fruits, due to its oxidant activity and ability to attack numerous cellular constituents. Ozone leaves no chemical residues on the food surface, decomposing itself rapidly in oxygen. Gaseous ozone has been already tested for table grapes storage and on wine grapes during withering.

The impact of grazing by cattle on Vitis vinifera L. cv. Shiraz vegetative growth and metabolite profile

Context and purpose of the study. Globally, vineyard cultivation uses conventional methods to manage pests, diseases and increase yield.

Extreme canopy management for vineyard adaptation to climate change: is it a good idea?

Climate change constitutes an enormous challenge for humankind and for all human activities, viticulture not being an exception. Long-term strategic changes are probably needed the most, but growers also need to deal with short-term changes: summers that are getting progressively warmer, earlier harvest dates and higher pH in musts and wines. In the last 10-15 years, a relevant corpus of research is being developed worldwide in order to evaluate to which extent extreme canopy management operations, aimed at reducing leaf area and, thus, limiting the source to sink ratio, could be useful to delay ripening. Although extreme canopy management can result in relevant delays in harvest dates, longer term studies, as well as detailed analysis of their implications on carbohydrate reserves, bud fertility and future yield are desirable before these practices can be recommended.

Monitoring water deficit in vineyards by means of Red and Infrared measurements

Vineyard water availability is one of the most important variables both in plant’s production and wine quality, once it regulates several processes, among which the stomata activity. To avoid water deficit, wine producers introduced artificial irrigation in their vineyard, using a semi-empirical process to calculate water amount.