Roles of organic soil amendments and soil organisms in the biological control of plant-parasitic nematodes: a review

Organic soil amendments stimulate the activities of microorganisms that are antagonistic to plant-parasitic nematodes. The decomposition of organic ma tter results in accumulation in the soils of specific compounds that may be nematicidal. Amendments are mainly bio-products and wastes from industrial , agricultural, biological and other activities. Control of plant-parasitic nematodes can be by improvements of soil structure and fertility, alterati on of the level of plant-resistance, release of nemato-toxic compounds), pa rasites (fungi and bacteria) and other nematode antagonistic (biological co ntrol agents). The mode of action of organic amendments leading to plant di sease control and stimulation of microorganisms is complex and dependent on the nature of the amendments. (C) 2000 Elsevier Science Ltd. All rights re served.