Structure of nematode communities in different agroecosystems in Croatia

Nematode community structure was analyzed in four different agroecosystems in order to determine how differences between crops and tillage treatment can influence nematode communities. The greatest total number of nematodes and greatest number of genera occurred in alfalfa. Significant differences in total number of nematodes occurred just in alfalfa compared to the other three treatments, and very significant differences in number of genera, also just in alfalfa. The lowest total number of nematodes and the lowest number of genera were determined in sugar beet. Trophic structure was similar in all treatments - dominated by bacterivorous and plant parasitic nematodes. Predators was the least present group in all treatments. Maturity index, Plant parasitic index and PPI/MI were calculated and there were no significant differences between MI and PPI/MI between the treatments. We can conclude that nematode community structure was most disturbed in sugar beet and in corn, which are both row crops with considerable impact of tillage on nematode communities. The lowest influence of tillage was in alfalfa, which is perennial crop where the nematode communities were less disturbed.