Plant Evolutionary Ecology, Institute of Evolution & Ecology, University of Tübingen, Tübingen, Germany.
Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain.
Glob Chang Biol. 2020 Nov;26(11):6511-6522. doi: 10.1111/gcb.15291. Epub 2020 Sep 1.
Predicting plant distributions under climate change is constrained by our limited understanding of potential rapid adaptive evolution. In an experimental evolution study with the invasive common ragweed (Ambrosia artemisiifolia L.) we subjected replicated populations of the same initial genetic composition to simulated climate warming. Pooled DNA sequencing of parental and offspring populations showed that warming populations experienced greater genetic divergence from their parents, than control populations. In a common environment, offspring from warming populations showed more convergent phenotypes in seven out of nine plant traits, with later flowering and larger biomass, than plants from control populations. For both traits, we also found a significantly higher ratio of phenotypic to genetic differentiation across generations for warming than for control populations, indicating stronger response to selection under warming conditions. As a measure for evolutionary rate, the phenotypic and sequence divergence between generations were assessed using the Haldane metric. Our approach combining comparisons between generations (allochronic) and between treatments (synchronic) in an experimental evolutionary field study, and linking population genomic data with phenotyping analyses provided a powerful test to detect rapid responses to selection. Our findings demonstrate that ragweed populations can rapidly evolve in response to climate change within a single generation. Short-term evolutionary responses to climate change may aggravate the impact of some plant invaders in the future and should be considered when making predictions about future distributions and impacts of plant invaders.
预测植物在气候变化下的分布受到我们对潜在快速适应进化的有限理解的限制。在一项对入侵性普通豚草（Ambrosia artemisiifolia L.）的实验进化研究中，我们将具有相同初始遗传组成的重复种群置于模拟气候变暖的条件下。对亲代和后代种群的 pooled DNA 测序表明，与对照种群相比，变暖种群与其亲本的遗传差异更大。在相同的环境下，与对照种群相比，变暖种群的后代在 9 个植物性状中的 7 个表现出更趋同的表型，表现为开花时间更早、生物量更大。对于这两个性状，我们还发现，与对照种群相比，变暖种群的表型和遗传分化在各世代之间的比值更高，这表明在变暖条件下对选择的反应更强。作为进化率的衡量标准，使用 Haldane 度量法评估了代际之间（异时性）和处理之间（同步性）的表型和序列分化。我们的方法结合了实验进化野外研究中的世代间（时间差异）和处理间（同步性）的比较，并将群体基因组数据与表型分析联系起来，为检测对选择的快速反应提供了有力的测试。我们的研究结果表明，豚草种群可以在一代内快速进化以适应气候变化。对气候变化的短期进化反应可能会加剧未来一些植物入侵的影响，在预测植物入侵的未来分布和影响时应考虑到这一点。
