Department of Botany, University of Innsbruck, Innsbruck, Austria.
Plant Cell Environ. 2021 Aug;44(8):2593-2603. doi: 10.1111/pce.14097. Epub 2021 May 28.
The heat resistance of meristematic tissues is crucial for the survival of plants exposed to high temperatures, as experienced during a forest fire. Although the risk and frequency of forest fires are increasing due to climate change, knowledge about the heat susceptibility of buds, which enclose apical meristems and thus enable resprouting and apical growth, is scarce. In this study, the heat resistance of buds in two different phenological stages was experimentally assessed for 10 European tree species. Cellular heat tolerance of buds was analyzed by determining the electrolyte leakage following heat exposure. Further, the heat insulation capability was tested by measuring the time required to reach lethal internal temperatures linked to bud traits. Our results highlighted differences in cellular heat tolerance and insulation capability among the study species. The phenological stage was found to affect both the thermal stability of cells and the buds' insulation. Further, a good relationship between size-related bud traits and insulation capability was established. Species-specific data on the heat resistance of buds give a more accurate picture of the fire susceptibility of European tree species and provide useful information for estimating tree post-fire responses more precisely.
分生组织的耐热性对于暴露在高温下的植物的生存至关重要，就像在森林火灾中经历的那样。尽管由于气候变化，森林火灾的风险和频率正在增加，但关于包含顶芽的芽对热的敏感性的知识却很少。在这项研究中，我们通过测量达到与芽特征相关的致命内部温度所需的时间来测试芽的隔热能力。我们的研究结果强调了研究物种之间细胞耐热性和隔热能力的差异。研究发现，物候阶段会影响细胞的热稳定性和芽的隔热能力。此外，还建立了与尺寸相关的芽特征和隔热能力之间的良好关系。有关芽耐热性的特定于物种的数据更准确地描绘了欧洲树种的火灾易感性，并为更准确地估计火灾后树木的反应提供了有用信息。
