Le infrastrutture ecologiche come elemento funzionale nella gestione della biodiversità degli agrosistemi, con particolare riferimento al vigneto

Ecological infrastructures as a functional element inthe management of biodiversity of agroecosystems, withparticular reference to the vineyardMany researchers have emphasized the importance of plantdiversity in agro-ecosystems on increasing the presence ofbeneficial arthropods that contribute to the control of harmfulspecies. In this context, a defense strategy to maintain ahigh level of biodiversity is the use of so-called “ecologicalinfrastructure” or “ecological compensation areas”, i.e.hedges or strips of vegetation adjacent to the cultivated fieldor inside. These sites provide alternate hosts and refugefor predators and parasitoids of pests, thereby increasingthe abundance of natural enemies and colonization ofneighboring crops. Some field studies have tested theconcepts of landscape ecology applied to agriculture, suchas the use of biological corridors to control harmful insectsthat breaking monocultures, are the bridge to the dispersalof natural enemies in the field, increasing their impact on thepests populations. The different species of the surroundingvegetation and the distances that natural enemies disperse intothe cropping system have a great influence on the abundanceand diversity of beneficial insects. The habitat managementis an aspect of conservation biological control using theappropriate ecological infrastructure in the agriculturallandscape that provides resources for food, shelter andalternative prey to enhance natural enemies. In vineyards,the enhancement of botanical diversity has beneficial effectsespecially in the relationships between grape moths andantagonists, leafhoppers and parasitoids as Anagrus spp.and mites and predators as Phytoseiid mites. Despite thepositive aspects of ecological infrastructures in the vineyard,unfavorable effects may occur in particular viticultural areasin relation to some pests such as leafhoppers, especiallythose vectors of grapevine phytoplasma and viruses diseases,scale and leafminers insects. In the paper we report thestate of studies carried out in Italy, Europe and other worldcountries on the role of natural hedges and floral resourcesin supporting predatory insects with particular referenceto Coccinellids and parasitoids of genus Anagrus andTrichogramma and associated natural enemies with tripids.In addition, we report briefly studies on the ecologicaleffectiveness on species richness and abundance of animalgroups and pollinators.