盐分胁迫对骆驼刺幼苗叶片性状的影响

气候变化与人为干扰使得干旱区盐渍化加剧,引发了严重的生态问题。因此,研究干旱区植物叶片性状对盐胁迫的响应具有重要意义。本研究以当年生的骆驼刺(Alhagi sparsifolia)为研究对象,采用盆栽控制试验,设置不同浓度(50、100、200、400mmol·L-1)的盐处理,分析盐胁迫对骆驼刺叶片性状的影响。结果表明,1)盐胁迫降低了骆驼刺的光合能力,其净光合速率和蒸腾速率显著减小,而水分利用效率则显著增大(P0.05);其荧光参数Fv/F0和Fv/Fm在盐处理下均低于对照处理;2)随盐浓度的增大,叶片的比叶面积逐渐减小,其干物质含量则是先减小后增大,且均低于对照;3)随盐浓度增大,单位质量叶片氮含量(Nmass)和单位面积叶片氮含量(Narea)先降低后升高再降低,单位质量叶片磷含量(Pmass)先降低后升高,单位面积叶片磷含量(Parea)则是先不变后升高,说明骆驼刺对盐分环境有一定的适应性。

Effects of salt stress on leaf traits of Alhagi sparsifolia

Desert region salinization is being accelerated because of climate change and anthropogenic disturb-ance,resulting in maj or ecological problems.Studying the leaf traits response of desert species to salt stress is of great importance to understand its adaptation to salinization.A pot experiment were applied to study the effect of different salt concentrations (50,100,200,400 mmol?L-1 )on leaf traits of Alhagi sparsifolia in the first growing season.The results showed that:(1 )Salt stress reduces the photosynthetic capacity of A.sparsifolia,the net photosynthetic rate and transpiration rate were significantly decreased,while water use efficiency is on the rise as salt stress increasing.The fluorescence parameters of Fv/F0 and Fv/Fm in the salt treatment were lower than the control.(2)With the increase of salt stress,the specific leaf area of A.sparsi-folia gradually reduced,the leaf dry matter content reduced first and then increased,and all of them were low-er than the control.(3)With the increase of salt stress,Nmass and Narea in leaves declined first and then ascen-ded,and reduced again.Pmass decreased first and then increased.However,Parea showed less change first and increased later.These results showed that the A.sparsifolia could adapt to saline environment morphological-ly and physiologically.