PREVENZIONE DELLA CONTAMINAZIONE DEI SUOLI ATTRAVERSO L’IMPIEGO DI OLI ESSENZIALI COME ALTERNATIVA AD ERBICIDI E ANTIPARASSITARI - VALUTAZIONE DELLA SOSTENIBILITA’ DEGLI OLI ESSENZIALI SULLA NEMATOFAUNA A VITA LIBERA

Intensive agriculture has over-exploited natural resources and altered soil system functions, primarily due to the excessive use of phytochemical products designed to ensure highquality and high-yield crop production. To promote more sustainable practices, new European guidelines aim to reduce pesticide usage by 50%. Natural products, such as essential oils (EOs), are considered promising green alternatives and are assumed to pose a low risk to the environment. However, before their widespread application, it is essential to evaluate their potential effects on suitable bioindicator organisms, such as nematodes. For this purpose, in a first step, the state of the art, current trends and future directions in the application of the EOs in agriculture have been investigated using the software VOSviewer. The software allowed us to select the most used EOs in crop protection and underlined that the main current scientific research focus is on plant-parasitic nematodes (PPNs) or, to a lesser extent, on model organisms. Therefore, it has been clearly emerged the need for broader-scale investigations to evaluate their eco-friendly nature. For this reason, a field study was conducted to evaluate the impact of EOs on the taxonomic and functional structure of nematode communities. Specifically, the experiment was carried out on chickpea crops from an organic farm and aimed to assess the potential influence of one of the most promising EOs, basil on free-living nematodes, thereby providing evidence of EOs’ contribution to preserving biodiversity and natural capital. Chickpea crops are often exposed to various biotic stresses, among which Fusarium wilt causes significant yield losses. Literature data suggest that coating chickpea seeds with basil EO can reduce Fusarium fungal infections. The seed coating has been obtained using chitosan (CHI), a natural, non-toxic, and edible polymer derived from the deacetylation of chitin, which is widely used in combination with EOs to reduce their high volatility and form a protective coating on seeds. The experiment was performed according to a BACI (BeforeAfter-Control-Impact) strategy that permits to distinguish the biological community changes related to differences in time elapsed or space vs. the changes caused by an environmental disturbance. The results obtained in this survey demonstrated that basil EO and chitosan seed coatings had no significant negative impact on nematode taxonomic diversity or functional indices. Additionally, the taxonomic community structure, considered one of the most sensitive detection metrics, revealed that observed effects were predominantly influenced by temporal changes, likely reflecting the natural progression of the crop system rather than the EO treatment itself. These findings are particularly promising, as they suggest that EO basil-based coating can preserve soil biodiversity and ecosystem functioning providing a new potential green alternative for crop protection.