Systemic induced resistance

Abstract

Systemic induced resistance (SIR) is multicomponent and depends upon the expression of genes for defense compunds found in disease resistant and susceptible plants. Since noninduced resistance (genetic) and SIR share common defense compounds, it is likely they also share the same signals and signal transduction pathway for regulating gene expression for resistance. The recognition of pathogens by resistant plants my, however, require highly specific and unique processes in addition to those associated with SIR. Salicylic acid participates in SIR though it is not the translocated signal for SIR. Several different pathways likely lead to SIR, and this may explain the many compounds which can elicit SIR. Oxidative stress may be central to some of the pathways for SIR. The induction of SIR by prooxidant herbicides and protection against damage caused by prooxidant herbicides and chemicals by pathogens and chemical inducers of SIR, suggests SIR involves antimicrobial defense compounds as well as those which protect against oxidative damage.