Fusarium wilt, caused by Fusarium oxysporum f. sp. lycopersici (FOL), is a worldwide tomato disease. Although Fusarium wilt management remains unsuccessful, enhancing host FOL resistance using magnesium oxide to activate plant immunity may enable effective control. We demonstrated that MgO-pretreatment of roots induced FOL resistance in susceptible tomato plants. Resistance was not induced in tomato mutants deficient in the jasmonic acid (JA) signaling pathway, whereas the opposite trend was observed in mutants deficient in the salicylic acid and ethylene signaling pathways, suggesting that JA signaling activation is essential for MgO-induced FOL immunity. Quantitative real-time polymerase chain reaction analysis of MgO-pretreated tomato plants, and challenge-inoculated with FOL, revealed that MYELOCYTOMATOSIS ONCOGENE HOMOLOG 2 (MYC2), the master regulator of JA signaling, as well as MYC2-targeted transcription factors that directly regulate the JA-induced transcription of late defense genes and their downstream wound-responsive genes were preferentially upregulated in both roots and stems. Moreover, in MgO-pretreated tomato plants challenge-inoculated with FOL, the late wound-responsive THREONINE DEAMINASE 2 (TD) gene was expressed earlier than its upstream genes, including MYC2, suggesting that a primed state for defense was established in MgO-pretreated plants. We conclude that MgO is a promising agent for the control of Fusarium wilt.

镰刀菌枯萎病，由尖孢镰刀菌f引起。sp. 番茄酱(FOL)，是一种世界性的番茄病害。尽管镰刀菌枯萎病的管理仍然不成功，但使用氧化镁激活植物免疫力增强宿主 FOL 抗性可以实现有效控制。我们证明了根的 MgO 预处理诱导了易感番茄植物的 FOL 抗性。在茉莉酸 (JA) 信号通路缺陷的番茄突变体中未诱导抗性，而在水杨酸和乙烯信号通路缺陷的突变体中观察到相反的趋势，表明 JA 信号激活对于 MgO 诱导的 FOL 免疫至关重要。对 MgO 预处理的番茄植株进行定量实时聚合酶链反应分析，并用 FOL 攻击接种，揭示MYELOCYTOMATOSIS ONCOGENE HOMOLOG 2 ( MYC2)，JA 信号传导的主要调节因子，以及直接调节 JA 诱导的晚期防御基因及其下游伤口反应基因转录的MYC2靶向转录因子在根和茎中优先上调。此外，在 MgO 预处理的番茄植株中，用 FOL 攻击接种，晚期伤口反应性苏氨酸脱氨酶 2 ( TD ) 基因的表达早于其上游基因，包括MYC2，表明在 MgO 预处理中建立了防御准备状态植物。我们得出结论，MgO 是控制枯萎病的有前途的药剂。