School of Forestry, Northern Arizona University, 200 E. Pine Knoll, Flagstaff, AZ 86011, USA.
Department of Plant Sciences, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA.
Genes (Basel). 2021 Nov 19;12(11):1826. doi: 10.3390/genes12111826.
Dissecting the genomic basis of local adaptation is a major goal in evolutionary biology and conservation science. Rapid changes in the climate pose significant challenges to the survival of natural populations, and the genomic basis of long-generation plant species is still poorly understood. Here, we investigated genome-wide climate adaptation in giant sequoia and coast redwood, two iconic and ecologically important tree species. We used a combination of univariate and multivariate genotype-environment association methods and a selective sweep analysis using non-overlapping sliding windows. We identified genomic regions of potential adaptive importance, showing strong associations to moisture variables and mean annual temperature. Our results found a complex architecture of climate adaptation in the species, with genomic regions showing signatures of selective sweeps, polygenic adaptation, or a combination of both, suggesting recent or ongoing climate adaptation along moisture and temperature gradients in giant sequoia and coast redwood. The results of this study provide a first step toward identifying genomic regions of adaptive significance in the species and will provide information to guide management and conservation strategies that seek to maximize adaptive potential in the face of climate change.
解析基因组适应本地环境的基础是进化生物学和保护科学的主要目标。气候的快速变化对自然种群的生存构成了重大挑战，而长世代植物物种的基因组基础仍知之甚少。在这里，我们研究了巨杉和海岸红杉这两个标志性的、具有重要生态意义的树种的全基因组气候适应。我们使用了单变量和多变量基因型-环境关联方法的组合，以及使用非重叠滑动窗口的选择扫描分析。我们确定了潜在适应重要性的基因组区域，这些区域与湿度变量和年平均温度表现出强烈的关联。我们的研究结果发现，这两个物种的气候适应具有复杂的结构，基因组区域显示出选择清除、多基因适应或两者结合的特征，表明巨杉和海岸红杉在湿度和温度梯度上存在近期或正在进行的气候适应。这项研究的结果为鉴定物种中具有适应意义的基因组区域提供了第一步，并将为指导管理和保护策略提供信息，这些策略旨在在气候变化面前最大限度地提高适应潜力。
