Nematodes

Introduction

Nematodes, sometimes called ‘roundworms’, are members of the animal Phylum Nematoda (Fig. 1). Nematodes:

Fig. 1. Nematode.

v are usually microscopic

v are often vermiform (worm shaped)

v are unsegmented without appendages

v are bilaterally symmetrical

v are pseudocoelomates (lack of a definite mesodermal lining for body cavity)

v are covered with cuticle

v have a complete digestive system (mouth, alimentary canal, anus)

v are usually sexual with tubular gonads

v have a nervous system

v are supported by longitudinal muscles but no circular muscles

v dispose of waste with an excretory system

v do not have a circulatory or respiratory system.

Nematodes have a wide range of habits. They can be

v parasites of vertebrates (e.g. Humans or other animals)

v parasites or associates of invertebrates (e.g. insects)

v parasites of plants

v free-living, feeding on bacteria, fungi, or algae in marine, fresh water, or soil habitats

v predators of nematodes and other microscopic invertebrates.

We focus on the management of soil-inhabiting nematodes.