Department of Chemical Ecology, Bielefeld University, D-33615, Bielefeld, Germany; Center for Biotechnology, Bielefeld University, D-33615, Bielefeld, Germany.
Plant Cell Environ. 2014 Jul;37(7):1574-85. doi: 10.1111/pce.12257. Epub 2014 Feb 11.
The phytohormones jasmonic acid (JA) and salicylic acid (SA) mediate induced plant defences and the corresponding pathways interact in a complex manner as has been shown on the transcript and proteine level. Downstream, metabolic changes are important for plant-herbivore interactions. This study investigated metabolic changes in leaf tissue and phloem exudates of Plantago lanceolata after single and combined JA and SA applications as well as consequences on chewing-biting (Heliothis virescens) and piercing-sucking (Myzus persicae) herbivores. Targeted metabolite profiling and untargeted metabolic fingerprinting uncovered different categories of plant metabolites, which were influenced in a specific manner, indicating points of divergence, convergence, positive crosstalk and pronounced mutual antagonism between the signaling pathways. Phytohormone-specific decreases of primary metabolite pool sizes in the phloem exudates may indicate shifts in sink-source relations, resource allocation, nutrient uptake or photosynthesis. Survival of both herbivore species was significantly reduced by JA and SA treatments. However, the combined application of JA and SA attenuated the negative effects at least against H. virescens suggesting that mutual antagonism between the JA and SA pathway may be responsible. Pathway interactions provide a great regulatory potential for the plant that allows triggering of appropriate defences when attacked by different antagonist species.
植物激素茉莉酸（JA）和水杨酸（SA）介导诱导的植物防御，相应的途径在转录和蛋白质水平上以复杂的方式相互作用。在下游，代谢变化对于植物-食草动物相互作用很重要。本研究调查了单一和联合施用 JA 和 SA 后斑叶车前叶组织和韧皮部渗出物的代谢变化，以及对咀嚼式（Heliothis virescens）和刺吸式（Myzus persicae）食草动物的影响。靶向代谢物分析和非靶向代谢指纹图谱揭示了不同类别的植物代谢物，它们以特定的方式受到影响，表明信号通路之间存在分歧、收敛、正交叉对话和明显的相互拮抗。韧皮部渗出物中初级代谢物库大小的植物激素特异性减少可能表明在源库关系、资源分配、养分吸收或光合作用中发生了变化。两种食草动物的存活率都因 JA 和 SA 处理而显著降低。然而，JA 和 SA 的联合应用至少对 H. virescens 减弱了负面影响，表明 JA 和 SA 途径之间的相互拮抗可能是原因。途径相互作用为植物提供了巨大的调节潜力，使植物在受到不同拮抗物种攻击时能够触发适当的防御。
