Modulation of reactive oxygen species activities and H2O2 accumulation during compatible and incompatible tomato–root-knot nematode interactions
Article first published online: 12 APR 2006
Volume 170, Issue 3, pages 501–512, May 2006
How to Cite
Melillo, M. T., Leonetti, P., Bongiovanni, M., Castagnone-Sereno, P. and Bleve-Zacheo, T. (2006), Modulation of reactive oxygen species activities and H2O2 accumulation during compatible and incompatible tomato–root-knot nematode interactions. New Phytologist, 170: 501–512. doi: 10.1111/j.1469-8137.2006.01724.x
- Issue published online: 12 APR 2006
- Article first published online: 12 APR 2006
- Received: 9 January 2006 Accepted: 13 February 2006
- tomato (Solanum lycopersicon);
- root-knot nematode;
- oxidative burst;
- plant defence mechanism
- • Here, the interaction of Melodoigyne incognita virulent and avirulent pathotypes with susceptible and Mi-resistant tomato (Solanum lycopersicon) has been studied. Significant differences in nematode penetration occurred 2 days postinoculation (dpi) and became stable from 3 dpi onwards. The hypersensitive cell response (HR) in resistant plants prevented the installation of the avirulent pathotype. The virulent pathotype overcame the Mi (nematode) resistance and induced feeding sites in root cells without triggering HR.
- • Reactive oxygen species (ROS), visualized by subcellular reduction of nitroblue tetrazolium, accumulated in nematode penetrated cells. Quantitative analyses with dichlorofluorescein indicated that the oxidative burst occurred very early with both pathotypes, with an enhanced rate in hyper-responsive cells.
- • Hydrogen peroxide (H2O2), detected by cerium chloride reaction, accumulated in the cell walls and especially in cells neighbouring HR. The apoplastic location of cerium perhydroxide indicated that either the plasma membrane or the cell wall was the primary site of the superoxide/H2O2 generator.
- • The data provide evidence, for the first time, for ROS-generated signals and their spatiotemporal expression in the host and nonhost interaction of tomato with nematodes.