The oxidative burst protects plants against pathogen attack: mechanism and role as an emergency signal for plant bio-defence--a review.

Various aspects, mechanisms and functions of the oxidative burst with generation of O2- superoxide anions in plant cells, which is stimulated by active defence-inducing agents such as fungal infection or elicitor treatment, were reviewed mainly on the basis of experimental evidence obtained in a system of Solanaceae plants and Phytophthora spp. The oxidative burst may be due to an O(2-)generating NADPH oxidase in the plasma membrane, which is activated with combinations of cytosolic proteins, Ca2+, calmodulin and protein kinase, following stimulation by elicitor molecules. The oxidative burst may play the role of an internal emergency signal for induction of the metabolic cascade for active defence.