Does the Presence of Detached Root Border Cells of Zea mays Alter the Activity of the Pathogenic Nematode Meloidogyne incognita?

Abstract

The root-knot nematode Meloidogyne incognita is a major pathogen of a range of important crops. Currently, control is typically achieved by the use of nematicides. However, recent work suggests that manipulating the ability of roots to slough off border cells, which then act as a decoy to the nematode, can significantly decrease damage to the roots. We investigated the attractiveness of border cells to M. incognita and the response of the nematode to border cells in close proximity. We found very limited attraction, in that nematodes did not preferentially alter direction to move toward the border cells, but a large and significant increase in nematode speed was observed once they were in the immediate vicinity of border cells. We discuss the results in the context of physical and biological mechanisms in relation to the control of pathogenic nematodes.

Banana Rhizodeposition: Characterization of Root Border Cell Production and Effects on Chemotaxis and Motility of the Parasitic Nematode Radopholus similis

“…In a preliminary test we determined the total phenolic content of rhizodeposition isolated from soil-grown plants using the Folin-Ciocalteu assay (Singleton and Rossi, 1965), but our results did not indicate a significant presence of phenolic compounds. Rodger et al (2003) used undiluted rhizodeposition of maize by rubbing the root tip over a medium plate. Subsequent inoculation with M. incognita juveniles did not result in attraction, as defined by the preferential alteration in direction towards rhizodeposition, but in a significant increase in nematode speed once in the immediate vicinity of border cells.…”

Carbon flow in the rhizosphere: carbon trading at the soil–root interface

“…Border cells also produce signal compounds involved in the protection of meristem against pathogens and in the promotion of symbiosis (Brigham et al 1995;Hawes et al 1998). Recent work has also suggested that border cells can act as a decoy luring pathogenic nematodes and fungi away from the main root axis (Gunawardena and Hawes 2002;Rodger et al 2003). However, contradictory results have also been found highlighting the difficulties of manipulating border cell release and physiology for disease control (Wuyts et al 2006;Knox et al 2007).…”

Rhizosphere fauna: the functional and structural diversity of intimate interactions of soil fauna with plant roots

“…However, only a narrow part of roots, between the tip and the root hair zone is vulnerable to nematode attack. Detached root border cells, secreted from root tips are suggested to play a significant role to misdirect plant-parasitic nematodes until the vulnerable part of the root has outgrown its attackers (Rodger et al 2003) (Fig. 2).…”

“…(1) Migrating rootfeeding nematodes locate roots by chemical gradients of rootspecific signals (Williamson and Gleason 2003). Root border cells (RBCs) can misdirect root feeding nematodes until the vulnerable part of the root tip has outgrown its attackers (Rodger et al 2003). (2) Once targeted, root invading nematodes secrete a wide array of enzymes and signal molecules specifically targeted to downregulate host defense responses and to modify host tissues (McKenzie Bird 2004), e.g.…”