Guo Wen-Yong, Lambertini Carla, Nguyen Loc Xuan, Li Xiu-Zhen, Brix Hans
Department of Bioscience, Aarhus University Ole Worms Allé 1, 8000, Aarhus C, Denmark ; State Key Laboratory of Estuarine and Coastal Research, East China Normal University Shanghai, 200062, China.
Department of Bioscience, Aarhus University Ole Worms Allé 1, 8000, Aarhus C, Denmark.
Ecol Evol. 2014 Dec;4(24):4567-77. doi: 10.1002/ece3.1286. Epub 2014 Nov 25.
Compared with non-invasive species, invasive plant species may benefit from certain advantageous traits, for example, higher photosynthesis capacity and resource/energy-use efficiency. These traits can be preadapted prior to introduction, but can also be acquired through evolution following introduction to the new range. Disentangling the origins of these advantageous traits is a fundamental and emerging question in invasion ecology. We conducted a multiple comparative experiment under identical environmental condition with the invasive haplotype M lineage of the wetland grass Phragmites australis and compared the ecophysiological traits of this invasive haplotype M in North America with those of the European ancestor and the conspecific North American native haplotype E lineage, P. australis ssp. americanus. The invasive haplotype M differed significantly from the native North American conspecific haplotype E in several ecophysiological and morphological traits, and the European haplotype M had a more efficient photosynthetic apparatus than the native North American P. australis ssp. americanus. Within the haplotype M lineage, the introduced North American P. australis exhibited different biomass allocation patterns and resource/energy-use strategies compared to its European ancestor group. A discriminant analysis of principal components separated the haplotype M and the haplotype E lineages completely along the first canonical axis, highly related to photosynthetic gas-exchange parameters, photosynthetic energy-use efficiency and payback time. The second canonical axis, highly related to photosynthetic nitrogen use efficiency and construction costs, significantly separated the introduced P. australis in North America from its European ancestor. Synthesis. We conclude that the European P. australis lineage was preadapted to be invasive prior to its introduction, and that the invasion in North America is further stimulated by rapid post-introduction evolution in several advantageous traits. The multicomparison approach used in this study could be an effective approach for distinguishing preadaptation and post-introduction evolution of invasive species. Further research is needed to link the observed changes in invasive traits to the genetic variation and the interaction with the environment.
与非入侵物种相比，入侵植物物种可能受益于某些有利性状，例如，更高的光合作用能力以及资源/能量利用效率。这些性状可能在引入之前就已预先适应，但也可能在引入新分布范围后通过进化获得。厘清这些有利性状的起源是入侵生态学中一个基本且新出现的问题。我们在相同环境条件下对湿地草本植物芦苇的入侵单倍型M谱系进行了多项比较实验，并将北美这种入侵单倍型M的生态生理性状与欧洲祖先以及同属的北美本地单倍型E谱系（芦苇美洲亚种）的生态生理性状进行了比较。入侵单倍型M在几个生态生理和形态性状上与北美本地同属单倍型E有显著差异，并且欧洲单倍型M的光合器官比北美本地的芦苇美洲亚种更高效。在单倍型M谱系内，引入北美地区的芦苇与其欧洲祖先群体相比，表现出不同的生物量分配模式和资源/能量利用策略。主成分判别分析沿着与光合气体交换参数、光合能量利用效率和回报时间高度相关的第一典型轴将单倍型M和单倍型E谱系完全分开。与光合氮利用效率和构建成本高度相关的第二典型轴，显著地将北美引入的芦苇与其欧洲祖先区分开来。综合分析。我们得出结论，欧洲芦苇谱系在引入之前就已预先适应入侵，并且北美地区的入侵受到引入后几个有利性状快速进化的进一步刺激。本研究中使用的多比较方法可能是区分入侵物种预先适应和引入后进化的有效方法。需要进一步研究将观察到的入侵性状变化与遗传变异以及与环境的相互作用联系起来。
