Short-term effects of different tillage in a sustainable farming system on nematode community structure

This study investigated the effects of different tillage practices on the nematode community structure. The different tillage systems were: untilled control, conventional deep plough, two-layer plough and cultivator. Sampling was carried out in a field experiment at Wörrstadt-Rommersheim (Rhineland-Palatinate, Germany) in order to study the effects of these tillage systems in a sustainable farming system. Soil samples were taken every 3 months from June 1994 to March 1995 and divided into two depths of 0–10 and 10–20 cm in order to study the vertical distribution of nematode density and community structure. Nematode density was significantly reduced after the first tillage. The second tillage had no effect on the nematode density, whereas the nematode community structure was strongly influenced on both structural (taxonomic) and functional (trophic group, life strategy) level. After tillage, the density of plant parasitic nematodes decreased and the density and dominance of bacterivorous nematodes increased. In the tilled plots, and especially in the cultivator and the two-layer plough plot, the nematode community was dominated by bacterial feeders, whereas, in the untilled control, plant feeders were more dominant. Our results showed that the nematode Maturity Index and Plant Parasite Index are suitable for indicating immediate tillage effects on the nematode community.