Ecology and evolution of a tree species challenged by dual threats

We are studying the ecological and evolutionary processes affecting the geographical distribution of southwestern white pine (SWWP; Pinus strobiformis), an important tree species of the Southwestern USA and Mexico. Southwestern white pine viability is threatened by changing climate and an invasive tree disease, white pine blister rust (caused by the fungal pathogen, Cronartium ribicola). Rapid climate change is negatively affecting SWWP by increasing heat and drought stress, and thus challenging its ability to adapt. White pine blister rust causes extensive tree decline and mortality, including in SWWP. The dual threats of climate change and invasive species make forecasting future tree distributions at continental scales an urgent challenge. The goal of our project is to determine how gene movement among populations, adaptation to disease and drought, heritable changes beyond DNA mutations, and a changing environment interact to govern the success of SWWP. We are utilizing and developing tools to help forecast and manage the future of the species, including those from genomics, common gardens, tree disease resistance testing, engineering, and technology innovation to measure drought tolerance and physiological response. Results will be synthesized and included in cutting-edge landscape genomics models to meet our overarching goal. We will present our framework and current project status, including results. Completed products include development of landscape genomic models, a species distribution model incorporating climate change, and adaptive trait, phenotype plasticity, and genomic variation analyses. Continuing work incorporates these aspects in addition to transgenerational plasticity research and a genome-wide association study.