Comunidade de nematóides do solo no ecossistema do Pampa Austral da Argentina sob diferentes sistemas de cultivo

Abstract

In the Southern Pampas of Argentina, Buenos Aires State, we determined the community structure of nematodes, under two tillage systems (no tillage and conventional tillage), with two rotations (crop-rotation and pasture and crop-rotation) and two conditions of fertilization, with the dose of nitrogen (N) 120 kg N ha-1 as urea (46-0-0) and without N. Were conducted four seasonal samplings, there was the extraction of soil nematodes by flotationcentrifugation. It was determined the genera that make up the different trophic groups present. We estimated the genera abundance, diversity index Shannon (H’), Simpson (Ds), evenness (J’) and richness (S), the relationships of trophic groups fungal feeders/bacterial feeders (m/b), fungal feeders / (bacterial feeders + fungal feeders) (m/m+b), and (bacterial feeders + fungal feeders)/plant parasites (m+b/fp) and maturity indices, Maturity index (MI), Maturity index without c-p 1 (MI 2-5), plant parasite index (PPI) and Yeates index (mMI). Was determined the faunal profile, by calculating the structural index (SI) and enrichment index (EI) and we calculated the channel index (CI). Finally it was determined the diversity index Shannon (H’), Simpson (Ds), evenness (J’) of nematodes community using molecular techniques (PCR/RFLP- polymorphisms of restriction fragments) for determining the molecular profile (fingerprinting).