Large-scale implementation of sustainable production practices in the Priorat-Montsant region

Abstract

The Priorat and Montsant Appellations of Origin are considered to produce some of the finest wines in the Mediterranean area of Spain. Located in the south of Catalonia (North-East Spain), they account for close to 4000 ha cultivated by more than 1300 vine growers under severe Mediterranean climatic conditions and hence threatened by global warming. In this context, sustainable practices are needed for the optimal use of natural resources in order to ensure the durability of high-quality wine production in the region. In addition, these practices allow this region to maintain high levels of biodiversity, a major characteristic of Priorat and Montsant's agricultural landscape, which represents an important touristic attraction. The Project LIFE Priorant+Montsant, funded by the European Union, proposed the implementation of sustainable practices at a regional scale, in order to achieve remarkable reductions of resource consumption in three axes: 1) Irrigation water management, 2) vine fertilization and 3) synthetic pesticide use. Reductions are achieved by providing the necessary technical support to growers to adopt practices, developing optimized strategies and evaluating the viticulture and winery production processes. After the two first seasons of the project, 2017 and 2018, the objectives of reduction of resources consumption have been successfully achieved. A total of 53 vineyard plots, representing the main grape varieties in the region (Grenache, Carignan, Cabernet Sauvignon and Syrah) were classified in eight sub-areas and monitored for water consumption. From pea-size to harvest (phenological stages), weekly 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. Overall, more than 50 irrigation recommendations were emitted to growers. The water consumption with the optimized irrigation strategy ranged from 10 to 63 litres per ha, the recommended dose saved 20 to 87% of the irrigation water per year, according to previous general recommendations in this region. Regarding fertilization, soil samples were provided by growers and leave samples were taken from vineyards to assess nutrient levels and develop the corresponding recommendation of fertilization, depending on the analysis results. The analyzed soil samples from the different sub-areas were grouped by the Principal Component Analysis, in which the first and second principal components accounted for 31.6% and 11.8% of the variability and were related to soil texture and nutrient content of soils, respectively. Overall, the recommended doses of organic fertilizers saved more than 20% of the usual chemical fertilizer application in the region. The reduction of pesticide use will be achieved through three actions related to three main pests and diseases of grapevine: optimized formulations against powdery mildew, alternative products to reduce copper use against downy mildew and, increase of surface under mating disruption strategy against grape berry moth Lobesia botrana. Before implementing these actions, no vineyards were managed under mating disruption in the Montsant area and 207 ha have been monitored in 2018 after two years. In the Priorat area, more than 200 ha have also adopted this strategy during the project. This action has saved more than 500 application doses of synthetic insecticides in those vineyards. Within the same scope, several formulations will be proved in the following years in order to assess their effectiveness against powdery and downy mildew in further specific field trials. Candidate products will be introduced in Integrated Pest Management strategies to achieve the desired pesticide reduction levels. The results will represent specific regional strategies for irrigation, fertilization and plant protection, and are extensible to most of the vineyards in Priorat and Montsant, as well as to other vitivinicultural regions which similar conditions. Keywords: Sustainable management, Irrigation, Fertilisation, Pesticides, Priorat-Montsant.