title: Climate drives adaptive genetic responses associated with survival in big sagebrush (Artemisia tridentata).
abstract: A genecological approach was used to explore genetic variation for survival inArtemisia tridentata(big sagebrush).Artemisia tridentatais a widespread and foundational shrub species in western North America. This species has become extremely fragmented, to the detriment of dependent wildlife, and efforts to restore it are now a land management priority. Common-garden experiments were established at three sites with seedlings from 55 source-populations. Populations included each of the three predominant subspecies, and cytotype variations. Survival was monitored for 5 years to assess differences in survival between gardens and populations. We found evidence of adaptive genetic variation for survival. Survival within gardens differed by source-population and a substantial proportion of this variation was explained by seed climate of origin. Plants from areas with the coldest winters had the highest levels of survival, while populations from warmer and drier sites had the lowest levels of survival. Survival was lowest, 36%, in the garden that was prone to the lowest minimum temperatures. These results suggest the importance of climatic driven genetic differences and their effect on survival. Understanding how genetic variation is arrayed across the landscape, and its association with climate can greatly enhance the success of restoration and conservation.
authors.affiliation: Plant and Wildlife Sciences Brigham Young University Provo UT USA; Present address: Department of Biology Snow College Ephraim UT USA.
authors.forename: Lindsay
authors.identifier: 0000-0002-1132-5156
authors.initials: L
authors.lastname: Chaney
authors.affiliation: USDA Forest Service Rocky Mountain Research Station Provo UT USA.
authors.forename: Bryce A
authors.initials: BA
authors.lastname: Richardson
authors.affiliation: U.S. Geological Survey Forest and Rangeland Ecosystem Science Center Boise ID USA.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Germino
keywords: adaptation; atmospheric decoupling; cold adaptations; minimum temperatures; polyploidy; population differentiation; survival analysis