Data from: Climate drives adaptive genetic responses associated with survival in big sagebrush (Artemisia tridentata)

A genecological approach was used to explore genetic variation for survival in Artemisia tridentata (big sagebrush). Artemisia tridentata is 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 five-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.本研究采用基因生态学（genecology）方法，探究了三齿蒿（Artemisia tridentata，英文名big sagebrush）的存活相关遗传变异。三齿蒿是北美西部分布广泛的建群灌木物种。如今该物种的生境已高度破碎化，对依赖其生存的野生动物造成了不利影响，因此开展该物种的恢复工作已成为土地管理的优先事项。研究在三个试验站点搭建了同质园（common garden）实验，所用幼苗来自55个源种群。这些源种群涵盖了该物种的3个主要亚种以及细胞型（cytotype）变异。本研究对幼苗的存活状况进行了为期5年的监测，以评估不同同质园及不同源种群间的存活差异。研究发现了与存活相关的适应性遗传变异证据：不同源种群在各同质园中的存活表现存在显著差异，且该差异的绝大部分可由源种群种子采集地的气候特征所解释。冬季气候最为寒冷的地区来源的种群，其幼苗存活率最高；而来自温暖干旱地区的种群，幼苗存活率最低。在最低温极易达到极值的试验同质园中，幼苗存活率最低，仅为36%。上述结果表明，气候驱动的遗传差异及其对物种存活的影响至关重要。解析遗传变异在景观尺度上的分布格局及其与气候的关联，可极大提升物种恢复与保护工作的成效。