Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
Animal Science and Technology College, Jilin Agricultural University, Changchun, 130118, China.
BMC Plant Biol. 2017 Nov 13;17(1):200. doi: 10.1186/s12870-017-1147-7.
Understanding how landscape factors, including suites of geographic and environmental variables, and both historical and contemporary ecological and evolutionary processes shape the distribution of genetic diversity is a primary goal of landscape and conservation genetics and may be particularly consequential for species involved in ecological restoration. In this study, we examine the factors that shape the distribution of genetic variation in a leguminous shrub (Caragana microphylla) important for restoration efforts on the Mongolian Plateau in China. This region houses several major bioclimatic gradients, and C. microphylla is an important restoration species because it stabilizes soils and prevents advancing desertification on the Inner Mongolia Plateau caused by ongoing climate change.
We assembled an expansive genomic dataset, consisting of 22 microsatellite loci, four cpDNA regions, and 5788 genome-wide SNPs from ten populations of C. microphylla. We then applied ecological niche modelling and linear and non-linear regression techniques to investigate the historical and contemporary forces that explain patterns of genetic diversity and population structure in C. microphylla on the Inner Mongolia Plateau. We found strong evidence that both geographic and environmental heterogeneity contribute to genetic differentiation and that the spatial distribution of genetic diversity in C. microphylla appears to result partly from the presence of a glacial refugium at the southwestern edge of its current range.
These results suggest that geographic, environmental, and historical factors have all contributed to spatial genetic variation in this ecologically important species. These results should guide restoration plans to sustain genetic diversity during plant translocations.
了解景观因素（包括地理和环境变量套件）以及历史和当代生态与进化过程如何塑造遗传多样性的分布，是景观和保护遗传学的主要目标，对于参与生态恢复的物种来说可能尤为重要。在这项研究中，我们研究了影响中国蒙古高原地区豆科灌木（柠条）遗传变异分布的因素。该地区有几个主要的生物气候梯度，柠条是一种重要的恢复物种，因为它可以稳定土壤，防止因气候变化导致的内蒙古高原沙漠化的进一步扩大。
我们组装了一个广泛的基因组数据集，包括来自十个柠条种群的 22 个微卫星位点、4 个 cpDNA 区域和 5788 个全基因组 SNPs。然后，我们应用生态位模型和线性及非线性回归技术，研究了历史和当代因素对内蒙古高原柠条遗传多样性和种群结构的影响。我们有强有力的证据表明，地理和环境异质性都导致了遗传分化，而柠条遗传多样性的空间分布似乎部分是由于其当前分布范围的西南边缘存在冰川避难所。
这些结果表明，地理、环境和历史因素都对这个生态重要物种的空间遗传变异产生了影响。这些结果应该指导恢复计划，以在植物移植过程中维持遗传多样性。
