Root-Knot Nematode


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root-knot nematode

[‚rüt ‚nät ′nēm·ə‚tōd]
(invertebrate zoology)
A plant-parasitic nematode species that induces galls or knots to form on roots.

Root-Knot Nematode

 

(Meloidogyne halpa, formerly Meloidogyne marioni), a parasitic worm of the family Tylenchidae, class Nematoda.

The root-knot nematode parasitizes on the roots of plants, causing the formation of round galls. Body length is 1.5-2 mm. The females are milk-white with bloated bodies; the males, with elongated bodies, are rarely found. Living inside the gall, the female lays about 2,000 eggs in a mucous egg sack. Microscopic larvae emerge from the eggs and infect the roots of neighboring plants or form their own galls alongside the mother’s; in this way large (to 2-3 cm) and complex galls develop. The root-knot nematode parasitizes predominantly in southern areas on the most varied hothouse, garden, melon, fruit-and-berry-bearing, and industrial crops. When it reproduces on a large scale the root-knot nematode causes gall nematodiasis in plants and frequently diminishes the harvest of a major crop (for example, cucumbers) by 40-60 percent. To combat root-knot nematodes either antinematode chemical preparations (nematocides) are used or the affected vegetable, melon, or other crop is excluded from crop rotation for two to three years.

References in periodicals archive ?
Use of marine algae for the management of root-knot nematode (Meloidogyne javanica) in okra and tomato plants.
Therefore, there is an increasing requirement for developing non-chemical alternative methods for the management of the root-knot nematode (HUANG et al.
enterolobii and induced cellular responses in roots of four Psidium species from the Active Germplasm Bank of the Embrapa Semiarid to guava root-knot nematode, comparing them with the susceptible commercial cultivar 'Paluma'.
The southern root-knot nematode (SRKN), Meloidogyne incognita infects a wide range of cultivated crops including tomato and is responsible for crop losses worth millions of dollars annually (Sasser and Freckman, 1987).
In addition, if the soil is infested with root-knot nematode (Meloidogyne spp.
One application of the latest sequencing effort will be the use of "molecular markers"--specific genomic regions that can flag the presence of nearby genes of interest, such as those for resistance to pests like the root-knot nematode.
Similarly, most of the investigated defense-related genes were shown to be induced in rice shoots, 3 days post infection in response to root-knot nematode, including the genes involved in pathways like phenylpropanoid, ethylene and PR proteins, however, many of these activated genes were found to be downregulated at 7 dpi (Kyndt et al.
Erecta) were the most types that suppressed the root-knot nematode infection during trials of 80 different ornamental annuals.
KIRSHNAPPA (1984): <<Response of tomato cultivars to three races of root-knot nematode Meloidogyne incognita>>, International Nematodes Network Newsletter, vol.