FOR 5571: Using clonal oak phytometers to unravel acclimation and adaptation mechanisms of long-lived forest tree holobionts to ecological variations and climate change

气候变化和全球物种灭绝是未来几十年对人类福祉的主要环境威胁。然而，尽管有200多年的有组织的林业和研究，关于(1)林木的表型可塑性，(2)关于树木与其微生物共生体的相互作用，以及(3)这些相互作用如何促进基于树木和/或其共生体的遗传变化的适应(调节变化)和适应(A&A)，仍然缺乏一些基本知识。因此，PhytOaketer试图通过建立大量的实验资源来开发新的树木模型，从而推导出完整的树木模型的驯化和适应(A&A)模式和机制。在实践中，我们将建立(I)具有充足组学资源的树木模型系统，以便于从完整的角度研究森林树木的A&A模式；(Ii)从完全的环境和胁迫控制到部分自然环境的中观实验；(Iii)将主要从幼树获得的实验结果与对成熟树木的观察相关联；以及(Iv)建立对包括极端地点在内的广泛自然条件下的模型树的监测。具体地说，我们将主要在三个克隆DF159的实验平台上进行工作，以(I)在两个生态加速器中进行受控实验，分别将全树暴露在两种中度干旱(较长期的干旱为前一年和当前一年，短期应激记忆为春季和夏季)和地上和地下食草动物；(Ii)将橡树无性系树苗暴露在成熟树木的树冠上，并与地面上的树冠和树苗进行比较；(Iii)评估在德国和欧洲投放的无性系橡树树苗，以分析在各种环境条件下的A&A机制。在子项目1-克隆橡树对非生物和生物胁迫的表观遗传驯化中，我们将研究与三个实验平台的干旱和草食处理有关的甲基化变化和转座元件。

Climate change and global species loss are the major environmental threats to human well-being in the coming decades. However, despite more than 200 years of organized forestry and research, some fundamental knowledge is still missing about (i) the phenotypic plasticity of forest trees, (ii) about the interplay of trees with their microbial symbionts, and (iii) about how these interactions may facilitate acclimation (regulatory changes) and adaptation (A&A) based on genetic changes of trees and/or their symbionts. Therefore PhytOakmeter seeks to derive such patterns and mechanisms of acclimation and adaptation (A&A) of a holobiont tree model by setting up substantial experimental resources to develop a new tree model. In practice, we will establish (i) a tree model system with sufficient -omics resources to facilitate the investigation of A&A patterns from a holobiont perspective in forest trees, (ii) mesocosm experiments ranging from complete environmental and stress control to mesocosm experiments with partly natural environments, (iii) relate experimental findings mostly gained from saplings to observations on mature trees, and (iv) establish the monitoring of model trees under a broad range of natural conditions, including extreme sites. Specifically, we will mainly work on three experimental platforms with the clone DF159 to (i) perform controlled experiments in two Ecotrons that expose the holobiont to two moderate droughts (previous year and current year for longer-term, spring and summer for shorter term stress memory) and above- and below-ground herbivory, respectively; (ii) expose oak clonal saplings in the canopy of mature trees in comparison to resident canopy twigs and saplings at ground level; and (iii) assess clonal oak saplings released across Germany and Europe for analyzing A&A mechanisms under a wide range of environmental conditions. In Subproject 1 - Epigenetic acclimation to abiotic and biotic stress in clonal oaks - we will investigate methylation changes and Transposable Elements in relation to the drought and herbivory treatment of the three experimental Platforms.