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IVES 9 IVES Conference Series 9 Efectos del deshojado y de su combinación con el aclareo de Racimos en los componentes básicos de la producción y del Mosto, sobre cv. Tempranillo en la D.O. Ribera del Duero

Efectos del deshojado y de su combinación con el aclareo de Racimos en los componentes básicos de la producción y del Mosto, sobre cv. Tempranillo en la D.O. Ribera del Duero

Abstract

[English version below]

Las técnicas de manejo del canopy de la vid pueden favorecer la adaptación de los sistemas de conducción a diversas condiciones de cultivo para obtener uva de calidad. Con este objetivo se desarrolló a lo largo de 3 años un ensayo en secano con la variedad Tempranillo conducida en espaldera, en la región vitivinícola de Denominación de Origen Ribera del Duero (España).
Se estudiaron los efectos del deshojado basal (aplicado en la fase de maduración, una vez pasado el envero), suprimiendo unas 4 hojas de la base de los pámpanos, y de su combinación con el aclareo de racimos (suprimiendo el 35 % de los racimos existentes en la cepa en el momento del envero) en el rendimiento, en el desarrollo vegetativo y en la composición del mosto.
Se ha observado que la combinación del aclareo con el deshojado redujo el rendimiento final en uva sólo un 20%, debido a la compensación producida por el aumento del peso de la baya. Dicho tratamiento presentó una tendencia a incrementar ligeramente el peso de madera de poda.
La concentración de azúcares en el mosto puede verse beneficiada por el deshojado basal, pero su combinación con el aclareo de racimos mostró un efecto muy claro a aumentar el grado alcohólico probable del mosto. La acidez total puede ser reducida por el deshojado, pero sobre todo cuando se practica junto con el aclareo de racimos.
En general, los efectos del aclareo de racimos en el envero combinado con el deshojado favorecen la evolución de la maduración, a costa de una reducción del rendimiento en uva, mientras que los efectos del deshojado simple en la variedad Tempranillo, a través de una reducción de los ácidos, dependen de las condiciones ambientales anuales en zonas como la D.O. Ribera del Duero.

The techniques of grapevine canopy management can help the training systems to become adapted to different growth conditions in order to improve the quality of the grapes. Focused on this objective, a trial was carried out over 3 years in the A.O. Ribera del Duero with the variety Tempranillo grown under non-irrigation conditions and trained as a vertical trellis system.
We have studied the effects of the basal leaf removal (in the ripening period, after veraison), taking out 4 leaves from the base of shoots, and of its combination with the cluster thinning (removing 35 %of vine clusters at veraison) in yield, vegetative development and must composition.
It was observed that the combination of cluster thinning and leaf removal reduced the final yield by only 20 %, due to the compensation caused by the increase of berry weight. This treatment showed a tendency to lightly increase the pruning weight.
Sugar concentration can be increased by the basal leaf removal, but the combination with the cluster thinning exhibited a clear effect to increase the probable alcoholic degree. Total acidity can be reduced by leaf removal, but basically in combination with cluster thinning.

DOI:

Publication date: February 24, 2022

Issue: Terroir 2000

Type: Article

Authors

Yuste, J.*, Rubio, J.A.*, Baeza, P.** and Lissarrague, J.R.**

*Servicio de Investigación Agraria de Castilla y León. Aptdo. 172. 47080 – Valladolid
** Dpto. Producción Vegetal. E.T.S.I. Agrónomos. Univ. Politécnica. 28040 – Madrid

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IVES Conference Series | Terroir 2000

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