摘要
对碱地肤幼苗进行盐、碱胁迫处理,通过测定各种溶质积累及分布特点,探讨碱地肤适应盐碱生境生理机制的部位差异,明确有机酸对其适应盐碱生境的贡献。结果表明,各种溶质在幼叶、成熟叶、幼茎、老茎及根等不同部位的分布存在明显差异,其中无论胁迫与否,有机酸均主要分布在茎叶之中,特别是在决定光合生产力的成熟叶片中。Na+、K+、Ca2+在不同部位的分布规律基本一致,表明Na+对K+、Ca2+的吸收与转运不存在拮抗竞争作用。实验证明了K+、Ca2+特殊的吸收机制及各溶质的分布特点对碱地肤抗盐碱生理是至关重要的;不论在盐胁迫还是碱胁迫下,有机酸在碱地肤不同部位特别是成熟叶中,均是参与渗透调节、离子平衡及pH调节的主导成分,是决定碱地肤适应盐碱生境的关键物质之一。实验同时也证明了碱地肤的不同部位对盐碱胁迫的适应机制有所不同。
The accumulation and distribution characteristics of various solutes from Kochia sieversiana seedlings stressed by salt and alkali were measured to study the physiological mechanisms in different parts of K.sieversiana and their role in adaptability to salt-alkalinized soil,and to identify the contribution of organic acid to salt-alkalinized habitat adaptability.There were considerable differences in the distribution of various solutes from different plant parts such as young leaves,mature leaves,young stems,old stems and roots.Organic acid was distributed mainly in stems and leaves,especially in mature and functional leaves on which photosynthetic productivity was dependent.Distributions of Na^＋,K^＋ and Ca^2＋ in different plant parts were uniform on the whole indicating that there was no competition for Na^＋,K^＋ and Ca^2＋ for absorption and transportation.Special absorption mechanisms of K^＋ and Ca^2＋ and distribution characteristics of various solutes from K.sieversiana were very important to its adaptability to salt-alkalinized soil.Organic acid in different parts,especially in mature leaves of K.sieversiana,was the dominant element in osmotic regulation,ion balance and pH adjustment,and was a key substance for the adaptation to saline and alkaline conditions.There were different adaptive mechanisms to salt and alkali stresses in different parts of K.sieversiana plants.
出处
《草业学报》
CSCD
北大核心
2013年第1期193-200,共8页
Acta Prataculturae Sinica
基金
国家自然科学基金项目(31072078)
新世纪人才项目(NCET-10-0153)
中国博士后基金(20100481042)
吉林省高校科研春苗培育计划项目(2013539)
吉林省教育厅项目(2010456
2009157)资助
关键词
碱地肤
盐胁迫
碱胁迫
有机酸
Kochia sieversiana
salt stress
alkali stress
organic acid
