Efficient irrigation strategies and water use reduction in the high quality production regions of Priorat and Montsant (Spain)

Abstract

Context and purpose of the study – Priorat and Montsant Appellations of Origin are located in the south of Catalonia (North‐East Spain), under severe Mediterranean climatic conditions, in terms of rainfall and water availability. Taking both appellations together, they account for close to 4000 ha cultivated by more than 1300 vine growers. Due to water stress during the growing season, irrigation is considered a suitable tool to ensure grape quality at harvest in order to maintain the high‐quality standard of these regions’ wines. However, optimal irrigation strategies based on plant water stress evaluation are not often undertaken, which may lead to inefficient water management. The objective of this study is to develop a regional irrigation strategy based on specific water potential measurements and meteorological data from different region sub‐areas, in order to achieve an overall 10% reduction of water consumption in the region.

Material and methods – During two growing seasons (2017 and 2018), a total of 53 vineyard plots were monitored, which represented the main grape varieties planted in the region (Grenache, Carignan, Cabernet-Sauvignon and Syrah) and were classified in eight sub‐areas inside the region. From pea‐size to harvest (phenological stages), measurements of phenology, water potential and meteorological data were collected. Irrigation recommendations were then given to growers, to avoid water potential below ‐1.4 MPa. Generic agronomic characteristics and production of the studied plots were also evaluated. Data on water use in the monitored vineyard network were compared to historical data of water use in the region. In addition, a specific field experiment was conducted to assess water consumption reduction using three different irrigation strategies.

Results – The monitoring of 53 vineyard plots per year was carried out during 2017 and 2018, with different meteorological conditions, accounting for a more water deficient season in 2017. Overall, more than 50 irrigation recommendations were emitted to growers. The water consumption with the optimized irrigation strategy ranged from 10 to 83 liters per ha, for the whole of 53 vineyards evaluated. Compared to the generic consumption reference of 80 l ha‐1, the recommended dose saved up to 87 % of the irrigation water per year. Moreover, two irrigation strategies also reduced water consumption compared to local grower strategy in the field trial comparing three strategies. The results of this study will help to develop an irrigation strategy, specific by region’s sub‐zones, in order to optimize water consumption while maintaining a high quality of the produced wines of this region.