Abundance and diversity of soil nematodes as influenced by different types of organic manure

Abstract

Summary: Nematode abundance and diversity from different types of organic manure soil treatments were investigated in a longterm field experiment carried out in Qu-Zhou experimental station, China Agricultural University. The composts used in the experiment were a traditional compost (C) (60 % straw, 30 % livestock dung, 5 % cottonseed-pressed trash and 5 % brans), traditional compost and chicken dung compost (60 % straw, 30 % chiken dung, 5 % cottonseedpressed trash and 5 % brans) added with effective microorganisms, EMC and EMCDC respectively. Six treatments were arranged according to a randomized block design with three replicates per treatment. Treatments were incorporation into the soil of compost EMC, EMCDC, and C each at the rates of 7.5 and 15 t/ha. Plots were sown with winter wheat (Triticum aestivum L.) and summer maize (Zea mays L.) every year from 1997 to 2004. Overall, 28 nematode genera were found. Seven genera were bacterivores, 3 genera were fungivores, 13 genera were plantparasites and 5 genera were omnivores-predators. The Rhabditis, Cephalobus, Helicotylenchus were dominant genera in the present study. The bacterivores and plantparasitic nematodes were the dominant trophic groups except in C treatment. Nematode abundance per 100 g dried soil ranged from 372 to 553. Addition of effective microorganism increased the number and proportion of bacterivorous nematodes and decreased the number and proportion of plant-parasitic nematodes compared to traditional compost C. Total number of nematode was significantly influenced by compost amount, but didn't significantly influence by EM agent. Total abundance of nematode was positively correlated with the content of soil organic matter, total N, available P and K. The long-term addition of EM agent hasn't adverse effect on soil nematode community. © 2010 Parasitological Institute of SAS.