Lab. Fisiología Vegetal, Facultad Biociencias, Universidad Autónoma de Barcelona, E-08193 Bellaterra, Spain.
Plant Sci. 2013 Nov;212:15-25. doi: 10.1016/j.plantsci.2013.07.012. Epub 2013 Aug 8.
The concept of hormesis in plants is critically reviewed, taking growth stimulation by low concentrations of toxic trace elements as a reference. The importance of both non-adaptive and adaptive mechanisms underlying ion-induced hormetic growth responses is highlighted. The activation of defense mechanisms by metal ions and pathogenic elicitors and the cross talk between the signals induced by metal ions and biotic stressors are considered. The production of reactive oxygen species and, consequently, the induction of stress-induced antioxidants, are key mechanisms in metal ion-induced hormesis in plants. It is concluded that in the current scientific literature, hormesis is used as an "umbrella" term that includes a wide range of different mechanisms. It is recommended that the term hormesis be used in plant toxicology as a descriptive term for the stimulated phase in growth response curves that is induced by low concentrations of toxic metal ions without evidence of the underlying mechanisms. If the mechanisms underlying the stimulated growth phase have been identified, specific terms, such as amelioration, defense gene activation, priming or acclimation, should be used.
植物中的毒物兴奋效应概念受到严格审查，以低浓度有毒微量元素对生长的刺激作用作为参考。强调了离子诱导毒物兴奋效应生长反应的非适应性和适应性机制的重要性。考虑了金属离子和病原激发子激活防御机制以及金属离子诱导的信号与生物胁迫因子之间的串扰。活性氧的产生，以及由此诱导的应激诱导抗氧化剂，是金属离子诱导植物毒物兴奋效应的关键机制。结论是，在当前的科学文献中，毒物兴奋效应被用作一个“伞状”术语，包含了广泛的不同机制。建议在植物毒理学中使用毒物兴奋效应一词来描述由低浓度有毒金属离子诱导的生长反应曲线中的刺激阶段，而无需证明潜在机制。如果已经确定了刺激生长阶段的机制，则应使用特定术语，例如改善、防御基因激活、启动或适应。
