Local adaptation of Nothofagus pumilio along the latitudinal gradient of the Andes

由于人为气候变化造成的压力事件和压力事件的增加，调查适应潜力的程度是进化森林生态学中一个至关重要和充满活力的研究领域。然而，这一研究领域的成功仍然受到基因组资源的限制，缺乏小规模的环境信息，以及自然种群中表型树的巨大挑战。在这个项目中，我们利用i）安第斯山脉纬度和地形梯度提供的独特机会来研究与光照和气候相关的途径中的地方适应，以及ii）在H2020 GenTree项目框架内为七种欧洲树种创建的基因组和表型资源。本研究的目标是i）确定具有生态和经济重要性的巴塔哥尼亚树种Nothofagus pumilio的当地适应性的遗传和表型基础，ii）确定人口历史，自然选择，基因流，和主要的环境驱动因素形成遗传多样性和局部适应性，以及iii）测试局部适应性是否在南方山毛榉和欧洲树种之间趋同进化。000个来自相关途径的候选基因，表型来自树木年轮数据（树状表型）来量化个体和种群对沿着安第斯山脉的纬度和气候东西梯度的环境差异的基因组反应。此外，使用树状表型，我们将调查树木的压力事件无关这些梯度，即ENSO相关的气候变化和虫害爆发的反应。与此同时，我们将使用中性遗传标记在关联研究中考虑种群的人口统计学历史，并确定基因流距离。最后，我们试图调查是否从巴塔哥尼亚和欧洲树种适应收敛到调查的选择压力。为此，我们将比较我们的结果与目前正在进行的研究相同的实验设计在七个欧洲树种。这些包括相对密切相关的森林山毛榉和栎，以及非常遥远的相关针叶云杉。除了更好地了解基本途径中地方适应的遗传基础外，查明遗传多样性、基因流动和地方适应的规模将有助于森林工作者了解情况，以执行更有针对性的森林遗传资源管理战略。例如，我们的结果可以转化为N. pumilio。

In the light of increasing stress events and stress episodes due to anthropogenic climate change the investigation of the extent of adaptive potential is a crucial and vibrant research field in evolutionary forest ecology. However, the success of this research field in general is still hampered by rather limited genomic resources, by the lack of small-scale environmental information, and by the huge challenge to phenotype trees in their natural populations.In this project, we take advantage of i) the unique opportunity that the Andean latitudinal and orographic gradients offer to study local adaptation in pathways related to light and climate, and ii) the genomic and phenotypic resources created for seven European tree species in the framework of the H2020 GenTree project.The goals of this study are i) to identify the genetic and phenotypic basis of local adaptation in the ecologically and economically important Patagonian tree species Nothofagus pumilio, ii) to determine the spatial scale at which demographic history, natural selection, gene flow, and major environmental drivers shape genetic diversity and local adaptation, and iii) to test whether local adaptation evolved convergently among Southern beech and European tree species.For these purposes, we will link genetic variation in a set of ~1,000 candidate genes from relevant pathways with phenotypes derived from tree ring data (dendrophenotypes) to quantify the genomic response of individuals and populations to environmental differences along the latitudinal and the climatic east-west gradient of the Andes. In addition, using dendrophenotypes, we will investigate the response of trees to stress events unlinked to these gradients, namely ENSO related climatic variability and pest outbreaks. In parallel, we will use neutral genetic markers to take the demographic history of populations into account in association studies, and to determine gene flow distances. Finally, we seek to investigate whether tree species from Patagonia and Europe adapted convergently to the investigated selective pressures. For this, we will compare our results with currently ongoing studies of identical experimental design conducted in seven European tree species. These include the relatively closely related Fagus sylvatica and Quercus robur as well as the very distantly related conifer Picea abies. Aside from a better understanding of the genetic foundation of local adaptation in essential pathways, identifying the scale of genetic diversity, gene flow and local adaptation will help inform foresters to implement more targeted management strategies of forest genetic resources. For example, our results can be translated into the identification of provenance zones for N. pumilio.