盐胁迫下白蜡根际微域的营养元素状况  

Nutrient status in rhizosphere microzone of Fraxinus americana under salt stress

作　　者：王利民[1,2] 陈金林[1] 黄东风[2] 杨静[1] 邢玮[1] 陈琴[1] 郭丽华[1] 

机构地区：[1]南京林业大学森林资源与环境学院,江苏南京210037 [2]福建省农业科学院土壤肥料研究所,福建福州350013

出　　处：《植物营养与肥料学报》2010年第6期1521-1526,共6页Journal of Plant Nutrition and Fertilizers

基　　金：国家"十一五"林业科技支撑计划专题(2006BAD09A0406)资助

摘　　要：为揭示根-土界面微域养分的吸收、累积与亏缺状况,运用X-射线电子探针研究盐胁迫对白蜡根际和根内营养元素相对含量及其分布的影响。结果表明,与对照(0 g/L)相比,低浓度(3 g/L)盐分处理使白蜡根系吸收较多的Ca、Mg、Cl等元素;而高浓度(9 g/L)处理则使根系吸收Ca、Mg、Cl的能力下降。白蜡根内Na、K、Fe的累积量和根际Na的含量随盐浓度增加均有升高;其中,过量的Na会破坏白蜡根细胞原生质膜的结构,引起胞内营养大量外泌,造成植物营养缺乏,从而诱发盐害。因此,Na在根际微域的累积是引起白蜡盐害的主要原因。The objectives of this research are to study nutrient absorption,accumulation and deficit in the root-soil interface of Fraxinus americana,and to provide the basis for plant salt-tolerance mechanism and solonchak improvement and utilization.X-ray electron probe was used to study the effect of salt stress on the distribution and relative content of nutrient elements in the rhizosphere and root tissue.The results indicate that contents of Ca,Mg,and Cl in roots of Fraxinus americana are high at the low concentration of salinity（3 g/L） compared to the control（0 g/L）,whereas at the high concentration of salinity（9 g/L） contents of Ca,Mg,and Cl in roots are low.Meanwhile,contents of Na,K,and Fe in roots and Na in the rhizosphere are increased with increasing levels of salinity.Consequently,the structure of plasma membrane in the cell is damaged by over-accumulation of Na in roots of Fraxinus americana and then indequate nutrition resulting from nutrition loss is induced,leading to salt injury.Therefore,the study implies that absorption and accumulation of Na might be main mechanism of generating salt injury.

关 键 词：盐胁迫 白蜡 根际 大量元素 微量元素 

分 类 号：S792.41[农业科学—林木遗传育种]