Data from: Predicting local adaptation in fragmented plant populations: implications for restoration genetics

Understanding patterns and correlates of local adaptation in heterogeneous landscapes can provide important information in the selection of appropriate seed sources for restoration. We assessed the extent of local adaptation of fitness components in 12 population pairs of the perennial herb Rutidosis leptorrhynchoides (Asteraceae) and examined if spatial scale (0.7 – 600km), environmental distance, quantitative Q_ST and neutral genetic differentiation F_ST, and size of the local and foreign populations could predict patterns of adaptive differentiation. Local adaptation varied among populations and fitness components. Including all population pairs, local adaptation was observed for seedling survival, but not for biomass, while foreign genotype advantage was observed for reproduction (number of inflorescences). Among population pairs, local adaptation increased with Q_ST and local population size for biomass. Q_ST was associated with environmental distance, suggesting ecological selection for phenotypic divergence. However, low F_ST and variation in population structure in small populations demonstrates the interaction of gene flow and drift in constraining local adaptation in R. leptorrhynchoides. Our study indicates that for species in heterogeneous landscapes, collecting seed from large populations from similar environments to candidate sites is likely to provide the most appropriate seed sources for restoration.

解析异质生境下局部适应的模式及其关联因子，可为生态修复中适宜种源的筛选提供关键理论支撑。本研究以菊科（Asteraceae）多年生草本植物Rutidosis leptorrhynchoides的12个种群对为研究对象，评估了其各适合度组分的局部适应程度，并检验了空间尺度（0.7~600 km）、环境距离、数量性状分化系数Q_ST（quantitative Q_ST）、中性遗传分化系数F_ST（neutral genetic differentiation F_ST）以及本地与外来种群的规模能否预测适应性分化的模式。局部适应程度在不同种群及各适合度组分间存在显著差异。综合所有种群对来看，幼苗存活率表现出局部适应，但生物量未呈现该特征；而繁殖相关性状（花序数）则表现出外来基因型优势。在各种群对之间，与生物量相关的局部适应程度随Q_ST值与本地种群规模的增大而提升。Q_ST值与环境距离显著相关，表明表型分化受到生态选择的驱动。然而，小种群中较低的F_ST值以及种群结构的变异，表明基因流与遗传漂变的共同作用限制了R. leptorrhynchoides的局部适应。本研究表明，对于栖息于异质生境中的物种，从与候选修复生境环境相似的大种群中采集种子，大概率可获得最适宜的生态修复用种源。