Differences in salinity tolerance of genetically distinct Phragmites australis clones
Differences in salinity tolerance of genetically distinct Phragmites australis clones
复制标题
DOI：
10.1093/aobpla/plt019
复制
发表时间：
2013-03-11
期刊：
影响因子：
2.9
通讯作者：
Brix H
中科院分区：
文献类型：
--
作者：
Achenbach L;Eller F;Nguyen LX;Brix H
芦苇是一种具有很高遗传变异性的无性系湿地牧草。克隆特有的差异反映在形态和生理特性上，从而反映在应对环境胁迫的能力上。15个不同的芦荟无性系对逐渐升高的盐度的反应揭示了与盐分回避和排斥有关的基因策略。盐胁迫对新梢伸长速率和光合作用的抑制作用在无性系间差异很大。这些差异可以部分归因于它们的地理范围，但与倍性水平无关。因此，遗传背景是影响不同芦荟无性系耐盐性的主要因素。不同的湿地草芦荟无性系在形态和生理上存在差异，因此它们对环境胁迫的适应能力也不同。我们分析了15个不同倍性水平(4n、6n、8n、10n、12n)和不同地理来源(罗马尼亚、俄罗斯、日本、捷克共和国、澳大利亚)的澳大利亚对虾无性系对逐步升高的盐度(8、16、24、32、40、56和72ppt)的反应。研究了无性系的地上部伸长速率、光合作用和部分特异离子积累，以评估与耐盐性相关的性状是否与无性系的遗传背景和地理起源有关。盐胁迫对所有无性系都有影响，但影响程度不同。最大高度从对照植物的1860 mm降低到40ppt盐度下的660 mm。在40ppt盐度之前，盐胁迫植株的芽伸长率在无性系之间差异很大。光饱和光合作用速率(Pmax)受到8ppt盐度的刺激，但在较高盐度时显著降低。气孔导度(GS)和蒸腾速率(E)随盐度的升高而降低。只有三个无性系在72ppt的盐度下存活下来，尽管它们的光合作用速率受到了强烈的抑制。盐胁迫植物的根和基叶积累了较高浓度的水浸提性Na+(分别为1646和1004µmolg−-1干物质(DM))和Cl-−(分别为1876和1400µmolg−-1 DM)。与对照相比，盐胁迫下植物体内的水提镁和钙离子浓度降低。各测定参数在无性系间的变异均大于无性系间。我们的结论是，不同的澳大利亚无性系的耐盐性差异很大，可以部分归因于它们的纵向地理起源，而不是PL。进一步的研究将有助于提高对该物种耐盐机制及其与遗传因素的联系的了解。
The common reed (Phragmites australis) is a clonal wetland grass with high genetic variability. Clone-specific differences are reflected in morphological and physiological traits, and hence in the ability to cope with environmental stress. The responses to progressively increasing salinity of fifteen distinct Phragmites australis clones reveal genotype-related strategies of salt avoidance and exclusion. The salinity-induced inhibition in shoot elongation rate and photosynthesis varies widely between clones. The differences can be partially attributed to their geographic range, but not correlated to ploidy level. Thus, the genetic background is a major factor influencing the salinity tolerance of distinct Phragmites australis clones. Different clones of the wetland grass Phragmites australis differ in their morphology and physiology, and hence in their ability to cope with environmental stress. We analysed the responses of 15 P. australis clones with distinct ploidy levels (PLs) (4n, 6n, 8n, 10n, 12n) and geographic origins (Romania, Russia, Japan, Czech Republic, Australia) to step-wise increased salinity (8, 16, 24, 32, 40, 56 and 72 ppt). Shoot elongation rate, photosynthesis and plant part-specific ion accumulation were studied in order to assess if traits associated with salinity tolerance can be related to the genetic background and the geographic origin of the clones. Salt stress affected all clones, but at different rates. The maximum height was reduced from 1860 mm in control plants to 660 mm at 40 ppt salinity. The shoot elongation rate of salt-exposed plants varied significantly between clones until 40 ppt salinity. The light-saturated photosynthesis rate (Pmax) was stimulated by a salinity of 8 ppt, but decreased significantly at higher salinities. The stomatal conductance (gs) and the transpiration rate (E) decreased with increasing salinity. Only three clones survived at 72 ppt salinity, although their rates of photosynthesis were strongly inhibited. The roots and basal leaves of the salt-exposed plants accumulated high concentrations of water-extractable Na+ (1646 and 1004 µmol g−1 dry mass (DM), respectively) and Cl− (1876 and 1400 µmol g−1 DM, respectively). The concentrations of water-extractable Mg2+ and Ca2+ were reduced in salt-exposed plants compared with controls. The variation of all the measured parameters was higher among clones than among PLs. We conclude that the salinity tolerance of distinct P. australis clones varies widely and can be partially attributed to their longitudinal geographic origin, but not to PL. Further investigation will help in improving the understanding of this species' salt tolerance mechanisms and their connection to genetic factors.
登录
查看更多内容
影响因子：
4.9
作者：
Cuin, TA;Shabala, S
通讯作者：
Shabala, S
影响因子：
1.8
作者：
Lissner, J;Schierup, HH;Astorga, V
通讯作者：
Astorga, V
影响因子：
6.4
作者：
MATOH, T;MATSUSHITA, N;TAKAHASHI, E
通讯作者：
TAKAHASHI, E
影响因子：
1.8
作者：
Mauchamp, A;Mésleard, F
通讯作者：
Mésleard, F
影响因子：
4.1
作者：
Christensen, Erik R.;Kusk, Kresten O.;Nyholm, Niels
通讯作者：
Nyholm, Niels