Plant-Microbe Interactions, Institute of Environmental Biology, Faculty of Science, Utrecht University, 3508 TB Utrecht, The Netherlands.
Phytochemistry. 2009 Sep;70(13-14):1581-8. doi: 10.1016/j.phytochem.2009.06.009. Epub 2009 Aug 25.
Beneficial soil-borne microorganisms can induce an enhanced defensive capacity in above-ground plant parts that provides protection against a broad spectrum of microbial pathogens and even insect herbivores. The phytohormones jasmonic acid (JA) and ethylene emerged as important regulators of this induced systemic resistance (ISR). ISR triggered by plant growth-promoting rhizobacteria and fungi is often not associated with enhanced biosynthesis of these hormones, nor with massive changes in defense-related gene expression. Instead, ISR-expressing plants are primed for enhanced defense. Priming is characterized by a faster and stronger expression of cellular defense responses that become activated only upon pathogen or insect attack, resulting in an enhanced level of resistance to the invader encountered. Recent advances in induced defense signaling research revealed regulators of ISR and suggest a model in which (JA)-related transcription factors play a central role in establishing the primed state.
有益的土壤微生物可以诱导地上植物部分增强防御能力，从而提供对广谱微生物病原体甚至昆虫食草动物的保护。植物激素茉莉酸（JA）和乙烯作为这种诱导系统抗性（ISR）的重要调节剂而出现。由植物促生根际细菌和真菌引发的 ISR 通常与这些激素的生物合成增强无关，也与防御相关基因表达的大量变化无关。相反，表达 ISR 的植物为增强防御做好了准备。启动的特征是细胞防御反应的更快和更强表达，只有在病原体或昆虫攻击时才会被激活，从而增强了对遇到的入侵者的抗性水平。诱导防御信号研究的最新进展揭示了 ISR 的调节剂，并提出了一个模型，其中（JA）相关转录因子在建立启动状态中发挥核心作用。
