Root Knot Nematode

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Root-knot Nematode Pathogen Root-knot nematode, Meloidogyne species Nematodes are microscopic round worms found in many habitats. Most are beneficial members of their ecosystems, but a few are economic parasites of plants and animals. There are several plant parasitic nematodes that cause problems on landscape. The most widespread and economically important are the root-knot nematodes. Host The host range of root-knot nematodes is so extensive that it is difficult to find common landscape and garden plants that are not hosts. Many vegetables, bedding plants, shrubs and trees are susceptible. Symptoms/signs Infections by root-knot nematode cause decline in the host, and under some conditions, may kill the plant. Infected plants may be stunted and chlorotic, usually wilt easily, and are not productive. However, the extent of damage caused by root-knot nematode infections varies with host, timing of infection, and cultural conditions. Root-knot nematode infection often is easy to identify because of the swellings in roots that look like “knots.” The swellings become large and easy to see on some hosts such as squash, but may be smaller and less conspicuous on others such as chile pepper. Multiple infections on one root result in a swollen, rough appearance. Root-knot nematodes are very small and can only be observed using a microscope. Disease Environmental conditions Unlike free-living nematodes that are numerous in all soils, plant parasitic nematodes must feed on a plant host in order to complete their life cycle. Root-knot nematodes are soilborne and feed on roots. Their life cycle includes egg, juvenile and adult stages. Eggs hatch into juveniles that infect plant roots and take nutrients from the plant as they mature, causing the characteristic knots or swellings to form. Root-knot nematodes feed by means of a stylet, a retractable
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