Caracterización de la comunidad de nematodos de suelo en cuatro sistemas productivos del sudeste bonaerense, Argentina.

This work evaluates the community of soil nematodes in agricultural and livestock environments with different intensity of land use in the southeast of the province of Buenos Aires. Nematodes were extracted from sites with different intensity of land use: corn (2 consecutive years of conventional tillage [LC]), potato (1 year of LC), soybean (direct seeding), and pastures (with grazing animals). 44 genera of nematodes belonging to 5 trophic groups were identified. The most abundant genera were Helicotylenchus, Pratylenchus and Cruznema. Significant differences were found in the structure of the nematode community between land uses. The total abundance and by trophic groups was higher in soybeans and pasture. Furthermore, in relation to the composition of the community of free-living nematodes (bacteriophages, frugivores, omnivores and predators), the sites with corn and soybeans presented a higher proportion of fungivores, while the sites with potatoes and grass showed a higher proportion of bacteriophages. In relation to phytophagous nematodes, the community associated with sites with greater agricultural disturbance (corn and potatoes) presented a different and less diverse assembly than those associated with sites with less disturbance (soybean and pasture). The nematological indices showed that the successional dynamics of the nematode communities were affected due to land use practices. This was confirmed through the analysis of the faunal profile, the majority of food chains, regardless of the type of land use, were affected by agronomic practices showing mature food webs. This work constitutes the first report on the composition of soil nematode communities in agricultural and livestock production fields in southeastern Buenos Aires, and contributes to understanding the ecology of soil nematode communities impacted by different anthropogenic practices. [ABSTRACT FROM AUTHOR]