Limited hydraulic adjustments drive the acclimation response of Pteridium aquilinum to variable light
Limited hydraulic adjustments drive the acclimation response of Pteridium aquilinum to variable light
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DOI：
10.1093/aob/mcaa006
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发表时间：
2020-03-13
期刊：
影响因子：
4.2
通讯作者：
Pittermann, Jarmila
中科院分区：
文献类型：
--
作者：
Baer, Alex;Wheeler, James K.;Pittermann, Jarmila
背景和目标：入侵植物的成功可以归因于许多特性，包括适应可变环境条件的能力。无论是通过适应，驯化还是表型可塑性。这些植物通常提高它们的资源利用效率，并因此提高它们的适应性。摘要本研究旨在探讨蕨类植物蕨菜（Pteridium aquilinum）在日照与遮荫条件下的水力与生理生态特性。方法：对阳坡和阴坡种群的叶片进行了抗空化、导水率、光合作用和膨压丧失点水势等水力学性状的测定。还记录了导管直径和长度、气孔密度和脉密度等解剖和结构特征。叶水势和气孔导度的昼夜措施补充这些data.Key结果：气体交换是近一倍的太阳植物，是水中心点利用效率，叶比电导率，气孔和静脉密度。这在很大程度上是通过减少叶面积，加上较高的木质部含量。阳生叶和阴生叶的叶柄抗空蚀性差异不显著，木质部比电导率差异也不显著。两种叶型的水力导管直径几乎相等。结论：叶面积和木质部含量的变化使蕨菜能够占据阳光充足的栖息地，并相应地调整其生理。高速率的光合作用部分解释了这种蕨类植物在干扰生境中的成功，虽然没有观察到内在的木质部品质，如抗气蚀性或导管长度的变化。这表明，与种子植物相比，P. aquilinum受到其基本身体计划的限制，种子植物表现出更大的水力调节能力。
Background and Aims: The success of invasive plants can be attributed to many traits including the ability to adapt to variable environmental conditions. Whether by adaptation, acclimation or phenotypic plasticity. these plants often increase their resource-use efficiency and, consequently, their fitness. The goal of this study was to examine the hydraulic and eco-physiological attributes of sun and shade populations of Pteridium aquilinum, a weedy fern. to determine whether the presence of vessels and other hydraulic attributes affects its success under a variety of light conditions.Methods: Hydraulic traits such as cavitation resistance, hydraulic conductivity, photosynthesis and water potential at turgor loss point were measured on fronds from sun and shade populations. Anatomical and structural traits such as conduit diameter and length, stomatal density and vein density were also recorded. Diurnal measures of leaf water potential and stomatal conductance complement these data.Key Results: Gas exchange was nearly double in the sun plants, as was water center dot-use efficiency, leaf-specific conductivity, and stomatal and vein density. This was largely achieved by a decrease in leaf area, coupled with higher xylem content. There was no significant difference in petiole cavitation resistance between the sun and shade leaves, nor in xylem-specific conductivity. Hydraulic conduit diameters were nearly equivalent in the two leaf types.Conclusions: Shifts in leaf area and xylem content allow P. aquilinum to occupy habitats with full sun, and to adjust its physiology accordingly. High rates of photosynthesis explain in part the success of this fern in disturbed habitats, although no change was observed in intrinsic xylem qualities such as cavitation resistance or conduit length. This suggests that P. aquilinum is constrained by its fundamental body plan, in contrast to seed plants, which show greater capacity for hydraulic adjustment.