Searching for drought-resistant genetic variants in Quercus cerris for future Austrian climate

S3.1 Assisted migration for adapting forests to climate change

Stockholm

2024

562

Bandaufführung

9087

40005299

The main objectives of our study are (1) to identify the genetic variants associated with drought stress resistance across Quercus cerris natural distribution, and (2) to screen the Austrian populations for such genetic variation. We plan on a phenotype-genotype association analysis of tree-ring width on dry years as a proxy for drought resistance, by means of ca 90 K SNPs detected with Single Primer Enrichment Technology (SPET). The first step of this analysis is to find regions in the current distribution of Q. cerris where the climate is comparable to predicted future conditions in Austria (IPCC climatic scenario RCP8.5). We established partnerships with research institutions in 14 countries, providing 40 locations of interest. In addition, we included 6,348 locations distributed evenly over the natural range of Q. cerris into our dataset. To represent Austria, we selected 34 locations where Q. cerris has high probability of presence in 2095 according to RCP8.5. Mean annual temperature, continentality, summer temperature, total annual precipitation and accumulated growing degree days are among the most important climatic variables for Q. cerris. The CHELSA dataset delivers data observations from 1981-2010 as well as predictions for RCP8.5 in the timeframe 2071-2100. We retrieved the observed variables for the locations of interest and the predicted variables for the 34 Austrian locations. Using the Elbow method, we established k=4 as the optimal number of clusters for this dataset. Interestingly, using Ward’s clustering algorithm with Euclidean distance, we observed that 3 of these clusters were represented in Austria. In sum, we report a meaningful approach to select relevant sampling locations to investigate the genetic variants underlying drought resistance in climatic regions similar to the future of Austria, bringing us one step closer to ensuring forest ecosystems sustainability.