Data from: Does origin always matter? Evaluating the influence of nonlocal seed provenances for ecological restoration purposes in a widespread and outcrossing plant species

For restoration purposes, nature conservation generally enforces the use of local seed material based on the “local-is-best” (LIB) approach. However, in some cases recommendations to refrain from this approach have been made. Here we test if a common widespread species with no obvious signs of local adaptation may be a candidate species for abandoning LIB during restoration. Using 10 microsatellite markers we compared population genetic patterns of the generalist species Daucus carota in indigenous and formerly restored sites (nonlocal seed provenances). Gene diversity overall ranged between He = 0.67 and 0.86 and showed no significant differences between the two groups. Hierarchical AMOVA and principal component analysis revealed very high genetic population admixture and negligible differentiation between indigenous and restored sites (FCT = 0.002). Moreover, differentiation between groups was caused by only one outlier population, where inbreeding effects are presumed. We therefore conclude that the introduction of nonlocal seed provenances in the course of landscape restoration did not jeopardize regional species persistence by contributing to inbreeding or outbreeding depressions, or any measurable adverse population genetic effect. On the basis of these results, we see no obvious objections to the current practice to use the 10-fold cheaper, nonlocal seed material of D. carota for restoration projects.

为开展生态恢复工作，自然保护实践通常基于“本地最优”（local-is-best, LIB）策略，强制要求使用本地种子材料。然而部分研究已建议摒弃该策略。本研究旨在检验：在生态恢复工作中，是否存在一类无明显本地适应迹象的广布常见物种，可作为放弃LIB策略的候选对象。本研究利用10个微卫星标记（microsatellite markers），对广布物种野胡萝卜（Daucus carota）在原生境及既往采用非本地种子种源进行恢复的生境中的种群遗传格局展开对比分析。整体基因多样性以期望杂合度（He）计介于0.67至0.86之间，两组生境未呈现显著差异。分层分子方差分析（hierarchical analysis of molecular variance, AMOVA）与主成分分析结果显示，原生境与恢复生境间存在极高水平的种群遗传混合，遗传分化程度可忽略不计（固定指数FCT=0.002）。进一步分析表明，种群分组间的遗传分化仅由一个异常种群导致，该种群被推测存在近交效应。据此本研究得出结论：在景观恢复过程中引入非本地种子种源，并未通过引发近交衰退或远交衰退，亦未产生任何可检测到的有害种群遗传效应，从而威胁区域物种存续。基于上述研究结果，我们认为在野胡萝卜（D. carota）的生态恢复项目中使用价格低廉10倍的非本地种子材料，并无明显不妥之处。