Climate Warming Facilitates Seed Germination in Native but Not Invasive Solidago canadensis Populations

Abstract

Plant performance is commonly temperature-dependent so that this performance could vary with climate warming. Seeds are among the most important propagules of plants, and seed traits strongly influence plant invasion success. Therefore, understanding seed traits under climate warming is useful for predicting invasion risks. To this end, we conducted a warming experiment with an infrared radiator and examined the effects of 5 years warming (approximately 2°C above ambient) on the seed quality and subsequent germination of Solidago canadensis from North America, where it is native (24 native populations), and from China, where it is invasive (29 invasive populations). Temperature regimes (i.e., ambient vs. warming) interacted with population sources (i.e., native vs. invasive) to significantly influence seed germination, but not thousand-seed mass. Warming significantly advanced the seed germination timing of native S. canadensis populations and increased their seed germination rate; warming did not influence the germination timing but decreased the germination rate of invasive S. canadensis populations. Across two temperature regimes combined, 24 native S. canadensis populations had smaller seeds, later germination timing, and lower germination rate than 29 invasive S. canadensis populations. These findings suggest that climate warming could facilitate the seed germination of native but not invasive populations. Our data also highlight that invasive populations might be more successful than native populations due to better seed quality and faster and higher seed germination.

Maternal effects of climate warming and nitrogen deposition vary with home and introduced ranges

“…This increase could enhance the potential of offspring to defend against stresses (Kant et al, 2015). This study suggests that climate warming and N deposition could yield stronger silver-spoon effects on S. canadensis populations from an introduced range than counterparts from a home range, and also provides evidence for the paradigm that maternal effects are strongly context dependent (Alba et al, 2016;Herman & Sultan, 2011;Marshall, 2008;Puy et al, 2021;Zhou & He, 2020). This shift with ranges might be linked to the environments of population origins (Drake et al, 2015).…”

“…Since the effects of climate change usually vary with ranges (e.g. the hypothesis of climate‐of‐origin, Drake et al., 2015) and there is different sensitivity in response to environmental changes among populations from disparate ranges (Alba et al., 2016; Peng et al., 2019; Zhou & He, 2020), it is necessary to address the maternal effects of climate change in the context of biogeography, particularly for invasive plants.…”

“…To this end, we first performed a 6‐year maternal experiment with perennial Solidago canadensis from North America (home range) and China (introduced range), which was subject to four manipulations consisting of warming and N‐addition, and then performed two offspring experiments to address how population source, warming and N‐addition interacted to influence offspring performance. Our first hypothesis was that the maternal effects of climate warming and N deposition might vary with home and introduced ranges of populations, because warming and N‐addition could differentially influence native and introduced populations (Alba et al., 2016; Peng et al., 2019; Zhou & He, 2020). Our second hypothesis was that the maternal effects of climate warming and N deposition might be adaptive because these two global changes could favour invasions (Dukes & Mooney, 1999; Liu et al., 2017).…”

Phenotypic plasticity of <i>Alternanthera philoxeroides</i> in response to simulated daily warming: Introduced vs. native populations

“…的重要因素 (Nicotra et al, 2010 (Richards et al, 2006); 另 一 方 面 , 表 型 可 塑 性 增 强 进 化 假 说 (evolution of increased phenotypic plasticity hypothesis)推测, 外来植物引入地种群可能比原产 地种群进化出了更强的表型可塑性 (Richards et al, 2006)。 以往对该假说的验证多集中于外来植物对光 照(张紫妍等, 2015)、水分 (Geng et al, 2006)、养分(周 方等, 2017)、邻体 (Zhang et al, 2019; 于良瑞等, 2020)以及天敌 (Liu et al, 2020)等的可塑性进化, 而 对模拟全天增温条件下入侵植物重要功能性状表 型可塑性进化的研究相对较少 (Hyldgaard & Brix, 2012)。仅有的几项研究多集中在温带 (Peng et al, 2019;Zhou & He, 2020), 并且多集中于关注植物生 长的相关性状 (He et al, 2012;Griffith et al, 2014), 而在热带地区开展以及关注植物草食作用及其抗 性的研究相对较少 (Paudel et al, 2020)。 喜旱莲子草(Alternanthera philoxeroides)是苋 科莲子草属一种多年生草本植物, 适合在水生和陆 地生境中生长 (Julien et al, 1995) 1 Effects of origin (i.e. introduced vs. native) and simulated daily warming (i.e.…”

Phenotypic plasticity of <i>Alternanthera philoxeroides</i> in response to simulated daily warming in the Tibet Plateau in introduced vs. native populations

“…全球变暖和生物入侵是全球生态变化的重要 研究内容 (Sala et al, 2000)。气候变暖对物种分布、 群落组成和生态系统结构有着至关重要的影响 (Shabani et al, 2020), 也为外来植物的入侵和扩张 创造了条件 (Sorte et al, 2013)。气候变暖条件下, 随 着"热岛"的形成和物种传播方式的改变, 植物能将 分 布 范 围 扩 张 到 更 高 纬 度 和 更 高 海 拔 的 地 区 (Walther, 2002)。对于年均气温较低的生境, 气候变 暖的影响更加显著 (Harvey, 1995;Janion-Scheepers et al, 2018)。 对温度响应的可塑性是植物成功入侵的关键 因素之一 (Hyldgaard & Brix, 2012)。已有研究指出, 在气候快速变化的背景下, 表型可塑性是植物适应 短 期 温 度 波 动 和 长 期 温 度 变 化 的 决 定 性 策 略 (Nicotra et al, 2010)。表型可塑性通常被定义为个体 基因型为响应环境变异而产生不同表型的能力 (Pigliucci, 2001), 在 生 物 入 侵 中 具 有 重 要 作 用 (Richards et al, 2006)。表型可塑性增强进化假说 (evolution of increased phenotypic plasticity hypothesis) 预测, 定植到新环境的入侵植物种群相比于原产地 种群具有演化出更强表型可塑性的潜力 (Richards et al, 2006)。此前对可塑性进化的研究涵盖了外来植 物性状对水分条件、光照变化、土壤养分、邻体根 系 以 及 天 敌 防 御 等 的 响 应 (DeWalt et al, 2004;Hawkins, 2018;于良瑞等, 2020;Lucob-Agustin et al, 2021;Yang et al, 2021) (Hyldgaard & Brix, 2012), 且已有的部分研究聚焦 于热带和温带地区 (Zhou & He, 2020;黄河燕等, 2021), 较少关注入侵植物在高寒地区对增温的响 应; 且研究多聚焦于植物适合度相关性状 (He et al, 2012;Ren et al, 2020), 而植物的防御性状(特别是 次生代谢抗性产物)很少报道 (Bauerfeind & Fischer, 2013)。 喜旱莲子草(Alternanthera philoxeroides, 又称 空心莲子草、 水花生)是苋科莲子草属一种原产于阿 根廷的多年生草本植物, 能适应多种生境且生长迅 速 (Holm et al, 1969), 现已广泛分布于欧洲和非洲 以外的大陆和岛屿 (Buckingham, 1995;Sainty et al, 1997) 1 Effects of simulated daily warming on fitness traits, functional traits and defense traits between two different origins (introduced and native) of Alternanthera philoxeroides (F (P)). BI, Branching intensity; RSR, Root to shoot ratio; SLA, Specific leaf area; SSL, Specific stem length.…”