Impact of sustainable farming interventions in the vineyard and its surrounding area on the dynamics of pests and natural enemies’ populations in Rioja Alavesa, Spain

Abstract: The intensification of vineyard management in modern viticulture has led to a
dramatic loss of biodiversity. The simplification of landscapes that indiscriminately eliminated elements that separate plots, weeds, and native flora has played a relevant role in the current proliferation of pests, provided those elements act as reservoirs of useful fauna. In organic vineyard management, biological control is gaining popularity to reduce pest pressure. These pest control processes can be naturally enhanced by introducing certain modifications in the vineyard that favour the presence of native natural enemies. The aim of this study was to assess the impact of the implementation of cover crops, green corridors, dry stone walls with native shrubs and vineyard biodiversity hotspots on the populations of Eotetranychus carpini and Empoasca vitis and on their natural enemies in Rioja Alavesa. To do that, their population dynamics were studied from May to September 2022 in four vineyards where ecological infrastructures (EI) had been implemented in 2020. E. carpini was rarely found, so the study of its population dynamics was not possible. Results showed that the population of phytoseiid mites was only favoured by spontaneous cover crop. Flowering cover crop and dry-stone wall with native shrubs increased the presence of mymarids, which showed an opposite pattern to E. vitis population dynamics. To sum up, our results highlighted the importance of maintaining vegetated margins of the vineyard and implementing cover crops between the vineyard rows in the Rioja Alavesa context for the biological control of pests.