查看文章

Systemic acquired resistance (SAR) is a plant defense state that is induced, for example, after previous pathogen infection or by chemicals that mimic natural signaling compounds. SAR is associated with the ability to induce cellular defense responses more rapidly and to a greater degree than in noninduced plants, a process called “priming.” Arabidopsis plants were treated with the synthetic SAR inducer benzothiadiazole (BTH) before stimulating two prominent cellular defense responses, namely Phe AMMONIA-LYASE(PAL) gene activation and callose deposition. Although BTH itself was essentially inactive at the immediate induction of these two responses, the pretreatment with BTH greatly augmented the subsequent PAL gene expression induced byPseudomonas syringae pv. tomatoinfection, wounding, or infiltrating the leaves with water. The BTH pretreatment also enhanced the production of callose, which …