Nematode Population Threshold Levels

  • N. G. Ravichandra


Although hundreds of different nematode species are associated with plants, not all are plant parasites. In several cases, phytonematode populations occur in numbers too small to cause serious plant injury. Limited information is available regarding potential economic losses associated with synergistic and antagonistic interactions between nematode species and the involvement of them in disease complexes. The evaluation of population threshold levels and the damage is of much significance. Nematodes from soil samples or infected plant parts must be extracted, identified, and counted in order to determine if one or more nematode species are causing poor plant growth. Hence, much emphasis has been given to the characterization of host sensitivity, host efficiency, and models in terms of population counts (Barker et al. 1985); with regard to host sensitivity, the development of tolerance limits or damage thresholds and the maximum number of nematodes that the plant may support without damage have received much attention. Major factors that influence host efficiency are reproduction factor of nematode, the nematode equilibrium density, and the maximum rate of nematode reproduction apart from the final population.


Life History Strategy Damage Threshold Nematode Species Damage Function Nematode Population 
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  1. Barker, K. R., & Noe, J. P. (1987). Establishing and using threshold population levels. In J. A. Veech & D. W. Dickson (Eds.), Vistas on nematology (pp. 75–81; 509 pp). Hyattsville: Society of Nematologists.Google Scholar
  2. Barker, K. R., Schmidtt, D. P., & Imbriani, J. L. (1985). Nematode population dynamics with emphasis on determining damage potential to crops. In K. R. Barker, C. C. Carter, & J. N. Sasser (Eds.), An advanced treatise on meloidogyne: Vol. 2. Methodology (pp. 135–148). Raleigh: North Carolina State University Graphics.Google Scholar
  3. Burt, O. R., & Ferris, H. (1996). Sequential decision rules for managing nematodes with crop rotations. Journal of Nematology, 28, 457–474.PubMedCentralPubMedGoogle Scholar
  4. Couch, H. (1995). Diseases of turfgrasses (3rd ed.). Malabar: Krieger Publishing.Google Scholar
  5. Ferris, H. (1978). Nematode economic thresholds: Derivation, requirements, and theoretical considerations. Journal of Nematology, 10, 341–350.PubMedCentralPubMedGoogle Scholar
  6. Ferris, H., & Wilson, L. T. (1986). Concepts and principles of population dynamics. In J. A. Veech & D. W. Dickson (Eds.), Vistas on nematology (pp. 372–376; 509 pp). Hyattsville: Society of Nematologists.Google Scholar
  7. Jatala, P., Jensen, H. J., & Shimabukuro, A. (1973). Host range of the “grass root-gall nematode”, Ditylenchus radicicola, and its distribution in Willamette Valley, Oregon. Plant Disease Reporter, 57, 1021–1023.Google Scholar
  8. Jones, F. G. W., & Perry, J. N. (1978). Modelling populations of cyst nematodes (Nematoda: Heteroderidae). Journal of Applied Ecology, 15, 349–371.CrossRefGoogle Scholar
  9. Manetsch, T. J. (1976). Time-varying distributed delays and their use in aggregative models of large systems. IEEE Transactions on Systems, Man, and Cybernetics, 6, 547–553.CrossRefGoogle Scholar
  10. Mitkowski, N., & Jackson, N. (2003). Subanguina radicicola, the root-gall nematode, infecting Poaannua in New Brunswick, Canada. Plant Disease, 87, 1263.CrossRefGoogle Scholar
  11. Nicholson, A. J. (1933). The balance of animal populations. Journal of Animal Ecology, 2, 132–178.CrossRefGoogle Scholar
  12. Nicholson, A. J., & Bailey, V. A. (1935). The balance of animal populations, Part 1. Proceedings of the Zoological Society of London, 3, 551–598.CrossRefGoogle Scholar
  13. Noe, J. P., & Barker, K. R. (1985). Relation of within-field variation of plant parasitic nematode population densities to edaphic factors. Phytopathology, 75, 247–252.CrossRefGoogle Scholar
  14. Pattison, A. B., Stanton, J. M., Cobon, J. A., & Doogan, V. J. (2002). Population dynamics and economic threshold of the nematodes Radopholus similis and Pratylenchus goodeyi on banana in Australia. International Journal of Pest Management, 48(2), 107–111.CrossRefGoogle Scholar
  15. Schmidt, K., Sikora, R. A., & Richter, O. (1993). Modeling the population dynamics of the sugar beet cyst nematode Heterodera schachtii. Crop Protection, 12, 490–496.CrossRefGoogle Scholar
  16. Seinhorst, J. W. (1966). The relationships between population increase and population density in plant-parasitic nematodes. I. Introduction and migratory nematodes. Nematologica, 12, 157–169.CrossRefGoogle Scholar
  17. Seinhorst, J. W. (1967). The relationships between population increase and population density in plant-parasitic nematodes. II. Sedentary nematodes. Nematologica, 13, 157–171.CrossRefGoogle Scholar
  18. Seinhorst, J. W. (1981). Growth and yield of oats at a range of Heterodera avenae densities and under different watering regimes. Nematologica, 27, 52–71.CrossRefGoogle Scholar
  19. Townshend, J. L., Eggens, J. L., & McCollum, N. K. (1973). Turfgrass hosts of three species of nematodes associated with forage crops. Canadian Plant Disease Survey, 53, 137–141.Google Scholar
  20. Walker, N. R., & Martin, D. L. (2002). Effects of sand-particle size on populations of ring nematode, Criconemella ornate. Phytopathology, 92, S84.Google Scholar
  21. Wallace, H. R. (1983). Interactions between nematodes and other factors on plants. Journal of Nematology, 15, 221–227.PubMedCentralPubMedGoogle Scholar

Copyright information

© Springer India 2014

Authors and Affiliations

  • N. G. Ravichandra
    • 1
  1. 1.AICRP (Nematodes) Department of Plant PathologyUniversity of Agricultural SciencesBangaloreIndia

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