Seed sourcing strategies have received considerable attention in the restoration literature and are a key component of effective management for restoration and conservation of natural areas. Research and discussion tend to focus on optimal distances and environmental similarities between seed sources and planting sites. However, given the increasing calls for assisted gene flow and assisted migration, greater consideration of translocating populations in specific directions across climatic gradients is warranted. To the extent that local adaptation proceeds primarily in response to climatic conditions, assisted gene flow across climatic gradients is likely to promote species persistence in the face of climate change. However, if species are adapted to other abiotic and biotic factors, translocating populations across climatic gradients may have unintended and potentially maladaptive consequences. Here, we used extensive collections of seed materials from across the state of Minnesota, a field planting that established common conditions at a location that was near the southern extreme of all the source locations, and subsequent aster modeling of fitness data to examine the overall fitness consequences of translocating populations across the landscape. We found that populations from cooler, northern sources tended to have higher fitness than those from warmer, more southern locations. In addition, populations from more northern locations tended to have earlier flowering phenology relative to populations from more southern sources, perhaps conferring a fitness advantage. Taken together, our results suggest that latitude of origin may be an important factor to take into consideration during seed source selection for restoration work, and that the direction of the effects can be at odds with expectations based on climatic considerations.

中文翻译：

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种子来源的纬度影响易地植物种群的开花物候和适应性

种子采购策略在恢复文献中受到了相当大的关注，并且是有效管理自然区域恢复和保护的关键组成部分。研究和讨论往往侧重于种子来源和种植地点之间的最佳距离和环境相似性。然而，鉴于对辅助基因流动和辅助迁移的呼声越来越高，有必要更多地考虑跨气候梯度在特定方向上迁移种群。就局部适应主要是对气候条件作出反应而言，跨气候梯度的辅助基因流动可能会促进物种在面对气候变化时的持久性。然而，如果物种适应了其他非生物和生物因素，跨气候梯度迁移人口可能会产生意外和潜在的适应不良后果。在这里，我们使用了来自明尼苏达州各地的大量种子材料收集，在靠近所有源位置最南端的位置建立了共同条件的田间种植，以及随后的适应度数据的紫菀建模来检查整体适应度跨景观迁移人口的后果。我们发现来自较冷的北部地区的种群往往比来自较温暖、较南部地区的种群具有更高的健康度。此外，与来自更南部地区的种群相比，来自更北部地区的种群往往具有更早的开花物候，这可能具有适应性优势。综合起来，