Effect of Silver Nanoparticles and Vermicompost on the Control of Longidorus elongatus (De Man, 1876) in Miscanthus × Giganteus and Its Growth and Development

Miscanthus × giganteus biomass plays a crucial role in producing renewable energy and bio-based products, supporting global sustainability objectives. However, its introduction into the European Union has made it susceptible to the ectoparasitic needle nematode Longidorus spp., which are known vectors of severe viral diseases. The aim of the presented research was to assess the effectiveness of the following soil amendments: vermicompost from Eisenia fetida and silver nanoparticles (Ag-NPs) applied to the soil with Miscanthus plants following artificial inoculation of Longidorus elongatus. A two-year experiment was conducted at the National Institute of Horticulture Research in Skierniewice using concrete rings filled with medium sandy soil amended with 10% peat. Treatments included: control (no amendments), vermicompost (4 L of E. fetida vermicompost), and Ag-NPs (60 mg/L soil). Each treatment was replicated four times. Application of both vermicompost and Ag-NPs positively influenced soil parameters and crop yield while suppressing nematode populations. Significant reductions in L. elongatus density were observed: vermicompost reduced nematode population by 80% and Ag-NPs by 90% compared to the control (15%).