The Effects of Soil Microbial Communities on Big Sagebrush (Artemisia tridentata) Seed Viability Vary with Translocation

Understanding the mechanisms by which populations are locally adapted to their environments is essential for predicting how species will respond to global change. However, past research has mostly focused on local adaptation to climate, rather than other possible drivers, such as species interactions, including interactions between plants and microbes. Artemisia tridentate (big sagebrush) populations are foundational and native to the Idaho steppe but are threatened by climate change and invasive species that increase the chances of wildfires. So, we questioned if big sagebrush is locally adapted to their soil microbial communities and sought out evidence of such a relationship. We hypothesized that there is a form of adaptation between sagebrush and their microbial communities and found this to be supported by our results. However, our results indicated that sagebrush populations could be both locally adapted and maladapted, depending on the origin of the soil microbial community. More importantly, the microbes reduced seedling viability overall, especially when the microbes were sourced in warmer soil than the seed's home location. This is crucial to recovering sagebrush populations because determining what increases seed viability will aid in restoration efforts across the Idaho steppe.