Data from: Assessing early fitness consequences of exotic gene flow in the wild: a field study with Iberian pine relicts

Gene flow from plantations of nonlocal (genetically exotic) tree provenances into natural stands of the same species is probably a widespread phenomenon, but its effects remain largely unexamined. We investigated early fitness consequences of intraspecific exotic gene flow in the wild by assessing differences in survival among native, nonlocal, and F1 intraspecific hybrid seedlings naturally established within two native pine relicts (one of Pinus pinaster and the other of P. sylvestris) surrounded by nonlocal plantations. We obtained broad-scale temporally sequential genotypic samples of a cohort of recruits in each pine relict, from seeds before dispersal to established seedlings months after emergence, tracking temporal changes in the estimated proportion of each parental cross-type. Results show significant proportions of exotic male gametes before seed dispersal in the two pine relicts. Subsequently to seedling establishment, the frequency of exotic male gametes became nonsignificant in P. pinaster, and dropped by half in P. sylvestris. Exotic zygotic gene flow was significantly different from zero among early recruits for P. sylvestris, decreasing throughout seedling establishment. Seedling mortality resulted in small late sample sizes, and temporal differences in exotic gene flow estimates were not significant, so we could not reject the null hypothesis of invariant early viability across parental cross types in the wild.源自非本地（遗传外来型）林木种源（provenance）人工林的基因流向同种天然林分（natural stands）的现象或为广泛分布，但该过程的生态效应迄今尚未得到充分研究。本研究聚焦野外条件下种内外来基因流（intraspecific exotic gene flow）的早期适合度后果（fitness consequences），通过评估两种被非本地人工林环绕的本土松属孑遗种群（其一为海岸松Pinus pinaster，其二为欧洲赤松P. sylvestris）内天然定植的本土型、非本地型及种内F1杂交幼苗的存活差异开展研究。我们针对每个松属孑遗种群中的一批补充更新个体（recruits）采集了大范围的时序性基因型样本，采样覆盖从扩散前的种子到萌发数月后已定植幼苗的全阶段，同时追踪各亲本杂交类型（parental cross-type）的估算占比随时间的动态变化。结果显示，在种子扩散（seed dispersal）前，两个松属孑遗种群中均检测到占比显著的外来雄配子（male gametes）。幼苗定植（seedling establishment）后，海岸松种群中外来雄配子的频率不再显著，而欧洲赤松种群中该频率下降了一半。欧洲赤松早期补充更新个体中的外来合子基因流（zygotic gene flow）显著不为零，且其占比随幼苗定植过程持续降低。由于幼苗死亡导致后期样本量偏小，且外来基因流估算值的时序差异未达到显著水平，因此我们无法拒绝“野外条件下各亲本杂交类型的早期存活能力无差异”的原假设（null hypothesis）。