Phenotypic drought stress prediction of European beech (Fagus sylvatica) by genomic prediction and remote sensing

Current climate change species response models usually do not include evolution. We integrated remote sensing with population genomics to improve phenotypic response prediction to drought stress in the key forest tree species European beech (Fagus sylvatica L.). We used whole-genome sequencing of pooled DNA from natural stands along an ecological gradient from humid-cold to warm-dry climate. We phenotyped stands for leaf area index (LAI) and moisture stress index (MSI) for the period 2016–2022. We predicted this data with matching meteorological data and a newly developed genomic population prediction score in a Generalised Linear Model. Model selection showed that the addition of genomic prediction decisively increased the explanatory power. We then predicted the response of beech to future climate change under evolutionary adaptation scenarios. A moderate climate change scenario would allow persistence of adapted beech forests, but not worst-case scenarios. Our approach can thus guide..., The sites selected for this study were in many regards typical for German beech forests. They comprised a large ecological amplitude with regard to long-term conditions. Within the range from humid-cold to warm-dry climatic conditions, important demographic and genetic processes in beech forests are taking place. Therefore, the aim of selection and stratification was to cover the climatic spectrum of forested areas in central and southern Germany to a large extent. For the characterisation of the climatic niche, we used the climatic marginality towards the rear edge, i.e. the dry and warm border of species distributions.
Construction of population pools, sequencing, population structure and genetic diversity
From each tree, 1-2 buds or 3-4 leaf discs of 0.5 mm diameter (approx. 50 mg of fresh plant material) were dried in Silicagel prior to homogenization. DNA was extracted using an in-house protocol. We constructed DNA pools per population using the same DNA quantity per individual be...,