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Conservative techniques, such as ground cover management, could help promote viticulture sustainability, which is a goal of conservation biological control, by providing shelter and food sources for predatory insects. A field experiment was conducted in a Mediterranean vineyard to evaluate ground cover management impacts on predatory insect and potential grapevine pest abundance and diversity, both on the ground and in the grapevine canopy. Three different ground cover management techniques (tillage, spontaneous cover and flower-driven cover) were tested for two years (2016 and 2017). Overall, the ground cover management significantly affected the abundance of important epigeal predators, of which carabids, forficulids and staphylinids were the most captured. The carabid abundances under both the cover crop treatments were found to be approximately three times higher compared with that under the tillage treatment. In contrast, the canopy insect abundance in the vineyard was similar among the treatments for both the predators and the potential grapevine pest species. These results indicate that cover crop vegetation can be used in vineyards to enhance predatory insect abundance and may improve agroecosystem resilience. [ABSTRACT FROM AUTHOR]

• Ground cover management clearly increased insect abundance at the ground level. • Few families dominated both epigeal and canopy insect assemblages. • Total biodiversity was higher in cover crop treatments than tillage. • Native plants positively influence generalist epigeal predator abundance and richness. Sustainable agriculture requires the support of new tools for successful and low-impact management of pests and diseases at global and local scales. The implementation of cover crops is considered a promising alternative ecological structure for sustainable agriculture, because they provide refuge to natural enemies of pests. Specifically, we hypothesised that implementing cover crop vegetation in a vineyard can enhance populations of natural enemies as a measure to support conservation biological control. We analysed insect abundance and diversity on Vitis vinifera var. Tempranillo (clon RJ-26, rootstock "110-Richter") in a Mediterranean vineyard located in La Rioja, Spain from spring to autumn 2016–2017. Two types of sampling systems (pitfall traps and vacuum sampling) were used in each of the three evaluated ground cover management approaches (n = 3): (i) tillage, (ii) spontaneous cover, and (iii) flower-driven cover. A total of 58 families that belonged to four functional subgroups of insects (predators, parasitoids, phytophagous insects, and pollinators) were found. Overall, differences among the three treatments were only detected for total abundance of insects collected in the ground traps, and the "spontaneous cover" treatment showed significantly higher predator richness and abundance. However, the higher Shannon–Wiener value was recorded for "flower-driven cover" at both the ground and canopy levels. In addition, the abundance of predators, parasitoids and phytophagous insects in the ground traps for both cover crop treatments was more than two times higher than that observed in "tillage" treatment. Several predator taxa, such as ants, ground beetles, earwigs, and vespoid wasps had significantly higher representation under spontaneous cover treatment. Moreover, for parasitoids, the "flower-driven cover" treatment revealed higher Hill numbers values (0D, 1D, and 2D) at the canopy level, although no significant differences were observed. These results indicate that vegetation cover could be used to promote beneficial entomofauna in vineyards and thus be an effective conservation biological control tool. [ABSTRACT FROM AUTHOR]