Diversity and role of plant-parasitic and free-living nematode communities in Italian vineyards.

Nematodes represent a diverse and widespread group of invertebrates, largely studied for their economic and ecological relevance. Their identification is important to arrange the proper management strategies that should be designed to maintain soil health and fertility, as well. A wide survey was conducted in 2024 in North Italy to study plant parasitic (PPNs) and free-living nematodes (FLNs) associated with Vitis vinifera vineyards. This study aimed to determine the prevalence and distribution of PPNs and FLNs in vineyards. Moreover, explanatory variables were used, to describe the influence of soil, climate and agricultural management factors in structuring the variation of nematode community composition. Fifty- three sampling sites from ten different vineyards were surveyed, and nematode species and genera were identified using an integrative approach. A total of approximately 3000 soil nematode individuals were found belonging to 16 different genera. The diversity of nematode communities associated with soil samples was determined using several ecological indices such as Dominance, Shannon-Wiener Index, Eveness, Margaleff, Equitability, Enrichment Index (EI), and Maturity Index (MI). The Nematode Indicator Joint Analysis (NINJA) tool, structural nematode dynamics, Correspondence and Food web analyses were also applied. The results obtained provide novel insights into the biodiversity and dynamics of terrestrial nematodes associated with Italian vineyards. The contribution of such biodiversity as an effective soil health bioindicator will be presented.