Reactive oxygen intermediates mediate a systemic signal network in the establishment of plant immunity.

MARIA ELENA ALVAREZ; PENNELL P.I,; MEIJER P-J,; ISHIKAWA A,; DIXON R.,; LAMB C.,

CELL PRESS

Lugar: United States; Año: 1998 vol. 92 p. 773 - 773

ecognition of an avirulent pathogen stimulates an oxidative burst generating O2 and H2O2, and these reactive oxygen intermediates (ROIs) cue the induction of defense genes and cell death in the development of defense genes and cell death in the development of a restricted lesion. This localized hypersensitive response (HR) is accompanied by the development of systemic acquired resistance to virulent pathogens. Here we show that inoculation of Arabidopsis leaves lead with avirulent Pseudomonas syringae induces secondary oxidative bursts in discrete cells in distant tissues,leading to low-frequency systemic micro-HRs. The primary oxidative burst induces these systemic responses,and both theprimary burst and the secondary microbursts are required for systemic immunity. Hence, ROIs mediate a reiterative signal network underlying systemic as well as local resistance responses.