Abstract

 

Defense priming allows plants to enhance their immune responses to subsequent pathogen challenges. Recent reports suggested that acquired resistances in parental generation can be inherited into descendants. Although epigenetic mechanisms are plausible tools enabling the transmission of information or phenotypic traits induced by environment cues across generations, the mechanism for the transgenerational inheritance of defense priming in plants has yet to be elucidated. With initial aim to elucidate an epigenetic mechanism for the defense priming in plants, we reassessed the transgenerational inheritance of plant defense, however, could not observe any evidence supporting it. By using the same dipping method with previous reports, Arabidopsis was exposed repeatedly to Pseudomonas syringae pv tomato DC3000 (Pst DC3000) during vegetative or reproductive stages. Irrespective of the developmental stages of parental plants received pathogen infection, the descendants did not exhibit primed resistance phenotypes, defense marker gene (PR1) expression, nor elevated histone acetylation within PR1 chromatin. In assays using pressure-infiltration method for infection, we obtained the same results with above. Thus, our results suggest that the previous observations on the transgenerational inheritance of defense priming in plants should be more extensively and carefully reassessed.