Plant parasitic nematodes are long tubular organisms that move over wet surfaces and feed on living plant cells. Most species found in soil are very small, about 0.2-2mm long and less 0.05mm wide should be observed by microscopes. Nematodes have digestive, reproductive and nervous systems, but no respiratory and circulatory systems. They parasite and inhabit all parts of plants, including buds, stems, leaves and roots, usually cause severe economic losses.