The Plant Journal · 1993 · 169 citations · 0 references
AgriculturePlant BiologyPlant SciencesPlant BiochemistryPlant Molecular BiologyPlant-microbe InteractionsPlant Defense ResponsesPlant Disease ResistancePlant Hormone SignalingPlant PathogenesisPlant-microbe SignalingSystemic Acquired ResistanceArabidopsis Systemic Acquired ResistanceBiotic Stress Responses Mediated By Salicylic AcidPathogenesis-related Gene ExpressionSalicylic Acid MetabolismSalicylic Acid-mediated Resistance
Salicylic acid (SA) has been proposed to play a role in the induction of pathogenesis-related (PR) proteins and systemic acquired resistance (SAR) in tobacco. Since SA is rapidly converted to salicylic acid beta-glucoside (SAG) in tobacco, we have attempted to assess the role of SAG in pathogenesis by application of chemically synthesized SAG to tobacco leaves. SAG was as active as SA in induction of PR-1 gene expression. This induction was preceded by a transient release of SA, which occurred in the extracellular spaces. The existence of a mechanism that releases SA from SAG suggests a possible role for SAG in SAR.