Short-Time Impact of Soil Amendments with Plant Materials on Soil Nematofauna.

Soil amendments with plant materials from species are widely acknowledged for a suppressive effect on plant-parasitic nematodes but their impact on beneficial components of soil nematofauna is still unknown. A study on potted tomato was carried out to investigate the short-time effects on the overall nematofauna of dry biomasses from six different species, i.e., , , , , and , incorporated to natural soil at 10, 20, or 40 g kg soil rates. All amendments resulted in a significant decrease of the total nematofauna biomass, whereas total abundance was significantly reduced only by , , and biomasses. Almost all the amendments significantly reduced the relative abundance of plant-parasites and root fungal feeders. All amendments significantly increased the abundance of bacterivores, whereas fungivores significantly increased only in soil amended with , and plant materials. and were the most abundant genera of bacterivores, whereas and prevailed among the fungivores. Predators were poorly influenced by all the tested biomasses, whereas the abundance of omnivores was negatively affected by and . Values of the Maturity Index and Sum Maturity Index were reduced by treatments with , , and plant materials, whereas most of the tested amendments decreased values of the Channel Index while increasing those of the Enrichment Index. Enrichment and bacterivore footprints raised following soil addition with biomasses, whereas composite and fungivore footprints were significantly reduced. According to their overall positive effects on soil nematofauna, amendments with plant materials or their formulated derivatives could represent an additional tool for a sustainable management of plant-parasitic nematodes.