铝胁迫下常绿杨根系有机酸和氨基酸的分泌  

Root Secretion of Organic Acids and Amino Acids of Evergreen Poplar Under Aluminum Stress

作　　者：钱莲文 李清彪[1] 孙境蔚 冯莹[2] QIAN Lianwen;LI Qingbiao;SUN Jingwei;FENG Ying(College of the Environment&Ecology,Xiamen University,Xiamen 361102,China;College of Resources and Environment Science,Quanzhou Normal University,Quanzhou 362000,China)

机构地区：[1]厦门大学环境与生态学院,福建厦门361102 [2]泉州师范学院资源与环境学院,福建泉州362000

出　　处：《厦门大学学报（自然科学版）》2018年第2期221-227,共7页Journal of Xiamen University：Natural Science

基　　金：国家自然科学基金(31100459);福建省科技厅农业引导性项目(2015N0033)

摘　　要：以常绿杨(Populus×euramericana)A-61/186树种为实验材料,探讨铝胁迫下其根系分泌物pH值及根系分泌有机酸和氨基酸的响应.结果显示,随着铝胁迫程度的加剧,常绿杨根系分泌物pH逐渐降低,铝胁迫下其根系分泌多种有机酸和氨基酸,但氨基酸含量远低于有机酸,这表明铝胁迫下常绿杨根系分泌物中氨基酸所起的生态作用可能与有机酸不同:有机酸主要通过与铝离子结合或者改变铝离子的存在形态而减轻铝毒害;而氨基酸由于含量的微量性,更多是以营养作用为主,对铝离子的解毒作用为辅.铝胁迫下常绿杨根系分泌物组成成分和分泌量的变化减弱了铝对常绿杨的毒性,这可能是常绿杨应对铝胁迫的一种自我保护机制.Aluminum stress experiments were conducted in hydroponic solution using evergreen poplar(Populus×euramericana cv.A-61/186)by measuring the pH values and the contents of amino acid and organic acid species in root exudates.The results showed that the pH value of the secretion of evergreen poplar decreased with increasing aluminum stress,and various organic acids and amino acids were secreted under the stress of aluminum,where the content of amino acids was much lower than that of organic acids.The results suggested that the ecological effects of amino acids in root secretions might differ from those of organic acids.Organic acids were mainly used to reduce aluminum toxicity by binding to aluminum ions or changing the presence of aluminum ions.Whereas,amino acids might be more nutritive,and be used as a supplement to detoxify aluminum ions.Therefore,changes in the composition and quantity of root secretions can reduce the toxicity of aluminum to evergreen poplar,which is a possible self-protection response mechanism of evergreen poplar to aluminum stress.

关 键 词：常绿杨 铝胁迫 根系分泌物 有机酸 氨基酸 

分 类 号：Q945.11[生物学—植物学]