INVERSE RELATIONSHIP BETWEEN THE NEMATODE MATURITY INDEX AND PLANT PARASITE INDEX UNDER ENRICHED NUTRIENT CONDITIONS

The maturity index, an ecological measure of the state of succession, is based on the composition of the nematode fauna. Nematodes that feed on higher plants were originally excluded; a separate plant parasite index was proposed for nematodes feeding on higher plants. In the pres ent study it is shown that, under certain conditions, the maturity ind ex and plant parasite index are inversely related. Therefore it is con cluded that the inclusion of plant feeders into the maturity index, as recently suggested, leads to an index which is less sensitive to chan ges in the environment than the original maturity index. The divergenc e of maturity index and plant parasite index is confirmed by literatur e data and is assumed to be a nutrient enrichment effect. The ratio be tween maturity index and plant parasite index is proposed as a sensiti ve parameter for monitoring agro-ecosystems. (C) 1997 Elsevier Science B.V.