Department of Plant Physiology; Institute of Plant Sciences; University of Graz; Graz, Austria.
Plant Signal Behav. 2013 Jul;8(7):e24798. doi: 10.4161/psb.24798. Epub 2013 Jul 1.
Phytohormones are essential regulators of various processes in plant growth and development. Several phytohormones are also known to regulate plant responses to environmental stress and pathogens. Only recently, cytokinins have been demonstrated to play an important role in plant immunity. Increased levels of cytokinins such as trans-zeatin, which are considered highly active, induced resistance against mainly (hemi)biotrophic pathogens in different plant species. In contrast, cis-zeatin is commonly regarded as a cytokinin exhibiting low or no activity. Here we comparatively study the impact of both zeatin isomers on the infection of Nicotiana tabacum by the (hemi)biotrophic microbial pathogen Pseudomonas syringae. We demonstrate a biological effect of cis-zeatin and a differential effect of the two zeatin isomers on symptom development, defense responses and bacterial multiplication.
植物激素是植物生长和发育过程中各种生理过程的重要调节剂。一些植物激素也被认为可以调节植物对环境胁迫和病原体的反应。直到最近，细胞分裂素才被证明在植物免疫中起着重要作用。增加细胞分裂素的水平，如被认为具有高度活性的反式玉米素，可以在不同的植物物种中诱导对主要（半）生物病原体的抗性。相比之下，顺式玉米素通常被认为是一种活性较低或没有活性的细胞分裂素。在这里，我们比较研究了这两种玉米素异构体对（半）生物病原体丁香假单胞菌感染烟草的影响。我们证明了顺式玉米素的生物学效应，以及这两种玉米素异构体对症状发展、防御反应和细菌增殖的差异效应。
