Irrigation frequency: variation and agronomic and qualitative effects on cv. Tempranillo in the D. O. Ribera del Duero

Abstract

The application of irrigation in vineyard cultivation continues to be a highly debated aspect in terms of the quantity and distribution of water throughout the vegetative growth period. This requires a deeper understanding of the influence that such application can have on the physiological activity of the vine in a context of climatic variation such as the current one. In this sense, it is operationally interesting to know the effect that the frequency of application of deficit irrigation during the vegetative cycle can have on the vegetative, productive and qualitative behaviour of the vineyard in order to optimise decision-making in its water management.

A work is proposed on the agronomic response to the variation in the frequency of deficit irrigation (30% ETo) during the summer, with three treatments: 2 irrigations per week (T03), 1 irrigation per week (T07), 1 irrigation every two weeks (T15), in cv. Tempranillo, grafted on 110R rootstock. The work was carried out throughout the period 2021-2023, in a vineyard located in the D.O. Ribera del Duero, with vine distances of 3.0 x 1.2 m, conducted in vertical trellis pruned as bilateral Royat cordon, where 4 blocks were established at random, with elementary plots of 48 vines, distributed in 4 rows, of which the 2 central rows were considered for control.

The results show interannual variation in the response of the vineyard to the frequency of deficit irrigation, both in terms of production and grape composition, with weekly irrigation (T07) being the most stable in its behaviour, while the other two frequencies were more variable, indicating that the highest frequency (T03) tended to favour vegetative growth, while the low frequency (T15) showed a certain tendency to increase acids in the grape.

It is advisable to extend the study of irrigation frequency in different soil types temporally and spatially, taking into account the overall response of the vineyard.