, Volume 78, Issue 4, pp 365–379

Ultrastructural investigation of clover roots during early stages of infection by the root-knot nematode,Meloidogyne incognita

  • Burton Y. Endo
  • William P. Wergin


Migration of root-knot larvae (Meloidogyne incognita) into the primary root tissues of red clover (Trifolium pratense, cult. “Kenland”) was accompanied by separation and subsequent compression of cells in front of and along the path of the penetrating nematode. The protoplasts of the parenchymatous cortical cells did not respond to the presence of the penetrating larvae. However, as the nematode approached the differentiating vascular tissue, the cytoplasmic density of the pericyclic and meristematic cells increased. This increased density was accompanied by an alteration in the morphological features of the nucleus. In addition to these changes, two different types of extracellular material were observed during penetration. A homogeneous substance appeared in and around the external opening of the amphid; and an electron dense material was found along the middle lamellae of the separating plant cells and between the cuticle of the nematode and the cell walls of the host.


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Copyright information

© Springer-Verlag 1973

Authors and Affiliations

  • Burton Y. Endo
    • 1
    • 2
  • William P. Wergin
    • 1
    • 2
  1. 1.U.S. Department of AgricultureNematology Laboratory, Agricultural Research ServiceBeltsville
  2. 2.U.S. Department of AgricultureSouthern Weed Science Research Laboratory, Agricultural Research ServiceStonevilleUSA

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