Response of physiological integration in Trifolium repens to heterogeneity of UV-B radiation
Response of physiological integration in Trifolium repens to heterogeneity of UV-B radiation
复制标题
白三叶生理整合对 UV-B 辐射异质性的响应
DOI：
10.1016/j.flora.2010.11.013
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发表时间：
2011-01-01
期刊：
影响因子：
1.9
通讯作者：
Meng, Qian-Cai
中科院分区：
文献类型：
--
作者：
Li, Qian;Liu, Xiao;Meng, Qian-Cai
许多克隆植物在资源异质性条件下存在生理整合。关于生理整合对异质性紫外线-B辐射的响应仍然知之甚少。为了验证白三叶（Trifolium repens）除了资源整合外，还可能存在防御整合的假说，测定了均匀和非均匀UV-B辐射（280-315 nm）下白三叶生理整合强度和生理参数的变化。为此目的，均匀和非均匀的紫外线-B辐射施加到对连接和切断分株的匍匐茎草本白车轴草。水和养分的整合强度的变化，其次是酸性品红染料和N-15-同位素标记的木质部水运输。通过测定叶绿素、紫外线吸收物质、可溶性糖和蛋白质含量以及超氧化物歧化酶（SOD）和过氧化物酶（POD）活性，研究了不同处理下叶绿素、可溶性糖和蛋白质含量的变化规律。当分株连接并暴露于非均匀UV-B辐射时，UV-B处理的分株向其连接的姊妹分株的水分运输速度显著降低，在UV-B辐射增强的标记分株中残留的N-15比例较高，而向未标记分株的转移比例较低。与均匀UV-B辐射下的无性系相比，将UV-B胁迫的无性系与未处理的无性系连接，其叶绿素含量、UV-B吸收物质含量、可溶性糖含量以及SOD和POD活性均显著提高。在非均匀UV-B辐射下，叶绿素和UV-B吸收化合物在相连分株间共享。这表明，生理连接提高了整个克隆植物在异质UV-B辐射下的表现。T.在非均匀UV-B辐射下，各分株的资源量减少，有利于受胁迫的分株。紫外线-B强调分株受益于非胁迫分株的生理整合，支持的假设，克隆植物能够优化其抗性维持其存在的效率也在不利的网站。研究结果有助于进一步了解异质UV-B辐射对克隆植物生长调节和微进化的作用。(C)2011年Elsevier GmbH。All rights reserved.
Physiological integration has been documented in many clonal plants growing under resource heterogeneity. Little is still known about the response of physiological integration to heterogeneous ultraviolet-B radiation. In this paper, the changes in intensity of physiological integration and of physiological parameters under homogeneous and heterogeneous ultraviolet-B radiation (280-315 nm) were measured in order to test the hypothesis that in addition to resource integration a defensive integration in Trifolium repens might exist as well. For this purpose, homogeneous and heterogeneous ultraviolet-B radiation was applied to pairs of connected and severed ramets of the stoloniferous herb Trifolium repens. Changes in intensity of water and nutrient integration were followed with acid fuchsin dye and N-15-isotope labeling of the xylem water transport. In order to assess the patterns of physiological integration contents of chlorophyll, ultraviolet-B absorbing compounds, soluble sugar and protein were determined and activities of superoxide dismutase (SOD) and peroxidase (POD) measured. When ramets were connected and exposed to heterogeneous UV-B radiation, the velocity of water transportation from the UV-B treated ramet to its connected sister ramet was markedly lower and the percentage of N-15 left in labelled ramets that suffered from enhanced UV-B radiation was higher and their transfer to unlabelled ramets lower. In comparison with clones under homogeneous ultraviolet-B radiation, the content of chlorophyll, ultraviolet-B absorbing compounds, soluble sugar and activities of SOD and POD increased notably if ultraviolet-B stressed ramets were connected to untreated ramets. Chlorophyll and UV-B absorbing compounds were shared between connected ramets under heterogeneous UV-B radiation. This indicated that physiological connection improved the performance of whole clonal plants under heterogeneous ultraviolet-B radiation. The intensity of physiological integration of T. repens for resources decreased under heterogeneous ultraviolet-B radiation in favor of the stressed ramets. Ultraviolet-B stressed ramets benefited from unstressed ramets by physiological integration, supporting the hypothesis that clonal plants are able to optimize the efficiency of their resistance maintaining their presence also in less favorable sites. The results could be helpful for further understanding of the function of heterogeneous UV-B radiation on growth regulation and microevolution in clonal plants. (C) 2011 Elsevier GmbH. All rights reserved.