Rhys G. R. Copeland

Plant-parasitic nematodes are found in most places in the world. The most prevalent ones have a broad host range, so wherever they are located, whether in a backyard garden or on a commercial farm, they are likely to be pests. For this reason, readily accessible, relatively inexpensive, and environmentally friendly methods of control have been sought and applied to control many species of these pests. One such control strategy is organic amendments, of which many types have been demonstrated as a potentially successful method for controlling different types of plant nematodes. This chapter discusses the biochemical and molecular mechanisms underlying the efficacy of organic amendments, the direct effects of active compounds, and the indirect adverse impact on various aspects of the life cycle of different plant-parasitic nematodes. Caveats in interpreting data on the applications of organic amendments to control nematodes and other factors that may dictate their efficacy are also discussed.