Lobo Albin, Hansen Jon Kehlet, Hansen Lars Nørgaard, Dahl Kjær Erik
Department of Geosciences and Natural Resource Management (IGN) University of Copenhagen Frederiksberg C Denmark.
Ecol Evol. 2018 Jan 25;8(4):2231-2239. doi: 10.1002/ece3.3824. eCollection 2018 Feb.
The ability of perennial species to adapt their phenology to present and future temperature conditions is important for their ability to retain high fitness compared to other competing plant species, pests, and pathogens. Many transplanting studies with forest tree species have previously reported substantial genetic differentiation among populations within their native range. However, the question of "how local is local" is still highly debated in conservation biology because studies on genetic patterns of variation within and among populations at the local scale are limited and scattered. In this study, we compare the level of genetic differentiation among populations of six different perennial plant species based on their variation in spring flushing. We assess the level of additive genetic variation present within the local population. For all six species, we find significant differentiation among populations from sites with mean annual temperature ranging between 7.4°C and 8.4°C. The observed variation can only be partly explained by the climate at the site of origin. Most clear relationship between early flushing and higher average spring temperature is observed for the three wind-pollinated species in the study, while the relations are much less clear for the three insect-pollinated species. This supports that pollination system can influence the balance between genetic drift and natural selection and thereby influence the level of local adaptation in long-lived species. On the positive side, we find that the native populations of woody plant species have maintained high levels of additive genetic variation in spring phenology, although this also differs substantially among the six studied species.
多年生植物物种使其物候适应当前和未来温度条件的能力，对于它们相较于其他竞争植物物种、害虫和病原体保持高适合度的能力而言至关重要。此前，许多针对林木物种的移植研究报告称，其原生范围内的种群间存在显著的遗传分化。然而，在保护生物学中，“多小算本地”这个问题仍备受争议，因为关于局部尺度上种群内部和种群之间遗传变异模式的研究有限且分散。在本研究中，我们基于六种不同多年生植物物种春季展叶的差异，比较了它们种群间的遗传分化水平。我们评估了本地种群中存在的加性遗传变异水平。对于所有六个物种，我们发现年均温度在7.4°C至8.4°C之间的不同地点的种群间存在显著分化。观察到的变异只能部分由原产地的气候来解释。在本研究的三种风媒传粉物种中，观察到最早展叶与较高的春季平均温度之间的关系最为明显，而对于三种虫媒传粉物种，这种关系则不太明显。这支持了授粉系统可以影响遗传漂变和自然选择之间的平衡，从而影响长寿物种的局部适应水平。从积极的方面来看，我们发现木本植物物种的本地种群在春季物候方面保持了高水平的加性遗传变异，尽管这在六个研究物种中也存在很大差异。
