Faculty of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan, 611130, PR China.
Faculty of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan, 611130, PR China.
Plant Physiol Biochem. 2015 Nov;96:436-47. doi: 10.1016/j.plaphy.2015.08.022. Epub 2015 Aug 31.
To investigate the traits contributing to the invasiveness of Alnus formosana and the mechanisms underlying its invasiveness, we compared A. formosana with its native congener (Alnus cremastogyne) under three light treatments (13%, 56%, and 100%). The consistently higher plant height, total leaf area, light-saturated photosynthetic rate (A(max)), light saturation point (LSP), light compensation point (LCP), respiration efficiency (RE), and non-photochemical quenching coefficient (NPQ) but lower root mass fraction (RMF) and specific leaf area (SLA) of the invader than of its native congener contributed to the higher RGR and total biomass of A. formosana across light regimes. The total biomass and RGR of the invader increased markedly with increased RMF, A(max), LSP, LCP, RE, stomatal conductance (G(s)) and total leaf area. Furthermore, compared with the native species, the higher plasticity index in plant height, RMF, leaf mass fraction (LMF), SMF, SLA, A(max) and dark respiration rate (R(d)) within the range of total light contributed to the higher performance of the invader. In addition, the activities of antioxidant enzymes were higher in the invader compared to the native, contributing to its invasion success under high/low light via photoprotection. With a decrease in light level, superoxide dismutase (SOD) and catalase (CAT) activities increased significantly, whereas total carotenoid (Car) and total chlorophyll (Chl) decreased; ascorbate peroxidase (APX) and glutathione reductase (GR) activities remained unchanged. These responses may help the invader to spread and invade a wide range of habitats and form dense monocultures, displacing native plant species. The results suggest that both resource capture-related traits (morphological and photosynthetic) and adaptation-related traits (antioxidant protection) contribute to the competitive advantage of the invader.
为了探究台湾桤木（Alnus formosana）入侵性的特征及其入侵机制，我们在三种光照处理（13%、56%和 100%）下，将台湾桤木与其原生同属种（赤杨叶（Alnus cremastogyne））进行了比较。与原生种相比，入侵种具有 consistently higher 的株高、总叶面积、饱和光下的光合速率（A(max)）、光饱和点（LSP）、光补偿点（LCP）、呼吸效率（RE）和非光化学淬灭系数（NPQ），但具有较低的根质量分数（RMF）和比叶面积（SLA），这导致了台湾桤木在不同光照条件下具有更高的 RGR 和总生物量。入侵种的总生物量和 RGR 随着 RMF、A(max)、LSP、LCP、RE、气孔导度（G(s)）和总叶面积的增加而显著增加。此外，与原生种相比，入侵种在株高、RMF、叶质量分数（LMF）、茎质量分数（SMF）、SLA、A(max)和暗呼吸速率（R(d））等方面具有更高的可塑性指数，这有助于其在总光照范围内具有更高的表现。此外，入侵种的抗氧化酶活性高于原生种，通过光保护有助于其在高光/低光下的成功入侵。随着光照水平的降低，超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性显著增加，而总类胡萝卜素（Car）和总叶绿素（Chl）减少；抗坏血酸过氧化物酶（APX）和谷胱甘肽还原酶（GR）活性保持不变。这些反应可能有助于入侵种传播和入侵广泛的栖息地，并形成密集的单一种群，从而取代本地植物物种。研究结果表明，资源获取相关特征（形态和光合）和适应相关特征（抗氧化保护）都有助于入侵种的竞争优势。
