Root-Knot Nematodes

Root-Knot Nematodes

 

a broad group of parasitic worms of the class Nematoda which cause galls on plant roots.

Root-knot nematodes are divided into four families that include five genera: Meloidogyne, Nacobbus, Hemicycliophora, Xiphinema, and Longidorus. The genus Meloidogyne contains more than 30 species, of which four are found in the USSR as well as throughout the world; they are M. hapla (earlier called M. marionï), M. incognita, M. arenaria, and M. javanica. The males are wormlike, reaching up to 2 mm; the females are puffed up and jug-shaped, with a length of about 1 mm. Root-knot nematodes are polyphagous, attacking more than 2,000 plant species (including vegetables and industrial plants, decorative and herbaceous plants, trees and bushes). Their development takes 19–45 days. A female inside a gall will lay as many as 2,000 eggs in her lifetime. As it develops in the egg, the larva of the nematode goes through its first molt, then emerges and embeds itself in the root, feeding voraciously on the juices of the host plant. Then it becomes either an immobile female or a mobile male that leaves the gall in search of a female.

Countermeasures include planting healthy material, crop rotation using crops that are resistant to root-knot nematodes, and treatment of the soil with chloropicrin, Nemagon, or Carbation.

REFERENCES

Ustinov, A. A. Gallovaia nematoda. Kharkov, 1959.
Kir’ianova, E. S., and E. L. Krall’. Paraziticheskie nematody rastenii i mery bor’by s nimi, vols. 1–2. Leningrad, 1969–71.

E. S. KIR’IANOVA

References in periodicals archive ?
The root-knot nematodes mortality increased with the increase in concentration and time of exposure.
Different nematode species attack vegetables and among these, nematodes of the genus Meloidogyne, commonly known as root-knot nematodes have been found seriously affecting okra all over the world (Hussain et al., 2016a, b).
Combination of solarisation and Dazomet or Calcium cyanamide results in good control of root-knot nematodes. Polythene sheets are readily available.
Global losses associated to root-knot nematodes (RKNs) alone from 75 countries as at 2000 was valued at $121 billion [12] and cost about $500 million for their annual control [13, 14].
Biology, identification and control of root-knot nematodes (Meloidogyne sp.) North Carolina State Univ., Graphics, 1978; 111.
Root-knot nematodes alone cause 5 percent of all crop losses around the world each year.
The member of genus Meloidogyne are known as root-knot nematodes, which induce feeding structures called "galls", each of which comprises of several giant cells (Jones and Payne, 1978).
Their topics include wild help for enhancing genetic resistance in lentils against fungal diseases, rice responses and resistance to planthopper-borne viruses at transcriptomic and proteomic levels, the power of omics to identify plant susceptibility factors and to study resistance to root-knot nematodes, transcriptomic analyses on the role of nitric oxide in plant disease resistance, and an overview of proteomic tools for understanding plant defense against pathogens.Distributed in the US by ISBS.