Sugar pine association genetics and performance in a post-fire restoration planting

Climate change is motivating a reassessment of how seeds are selected for reforestation, as rapid environmental change can lead to local maladaptation in trees. Genetic association studies and past seed source climate both have the potential to help identify appropriate planting stock, but these techniques have not been compared and tested as part of an operational planting program. In this study, we combined an analysis of SNPs associated with environmental gradients in sugar pine (P. lambertiana) with an analysis of post-fire seedling survival and growth in a restoration experiment. Our genotype-environment association (GEA) tests revealed 829 SNPs (single nucleotide polymorphisms) with significant association with climate gradients – especially April snowpack – 323 of which either had annotations that suggested potential functional importance or were identified by two different methods. We then built Bayesian models of survival and growth for all seedlings to test the effects of sour...