Effects of silver, gold and platinum nanoparticles on selected nematode trophic groups

Abstract

Abstract Nematodes represent different trophic groups in the soil. They therefore play an important role in the soil environment: they regulate populations of other soil organisms, mineralize nutrients into plant-available forms, provide a source of food for other soil organisms and feed on pathogenic organisms and plant pests. In contrast, plant-parasitic nematodes are important pests of crops. Nanoparticles are increasingly being used in agriculture and other production sectors. They are present in the soil, not necessarily in trace amounts, and can affect a variety of soil organisms, including nematodes. Under laboratory conditions, the effects of silver (Ag), gold (Au) and platinum (Pt) nanoparticles on the biological activity of selected nematode species from two trophic groups: entomopathogenic nematodes (Heterorhabditis bacteriophora and Steinernema feltiae) and plant parasitic nematodes (Xiphinema diversicaudatum, Ditylenchus dipsaci, Heterodera schachtii) were studied. The plant-parasitic nematodes tested responded differently to nanoparticle solutions. The greatest sensitivity to Ag nanoparticles was observed in D. dipsaci. The best effect of Au nanoparticles was observed in H. schachtii. Lead caused a positive response in D. dipsaci, in contrast to H. schachtii, compared to the control. In contrast, X. diversicaudatum and H. baltica were not affected by Pt nanoparticles. Despite similar concentrations silver nanoparticles, compared to Au and Pt nanoparticles, had the strongest toxic effects on the infective juveniles of both EPN nematode species tested. However, during the migration of a new generation of EPN infective juveniles from a dead insect, the results were inconclusive. For H. bacteriophora, the number of IJs nematodes migrating outside the cadaver after contact with AgNP and PtNP was higher compared to the control and other nanoparticles. The results encourage field research into increasing the efficacy of entomopathogenic nematode biopreparations using nanoparticles and reducing the harmfulness of plant parasitic nematodes in crops.