人心果在NaCl胁迫下的离子效应及耐盐方式

为了研究人心果在NaCl胁迫下的离子效应及耐盐方式,本试验测定了人心果根、枝条、叶在NaCl胁迫下Cl-、Na+、K+、Ca2+的含量及分布特点.结果表明,人心果根、枝条、叶的Cl-、Na+、Ca2+含量随处理浓度升高而升高,K+、K+/Na+随处理浓度升高而降低.在8‰处理浓度时,根、枝条、叶的Cl-含量分别为对照的8.94、6.77、4.49倍,Na+含量分别为对照的2.16、2.88、2.45倍,K+/Na+分别为0.13、0.43、0.35.相同处理浓度下,根的Cl-、Na+含量均最高,含量高低顺序如下:Cl-:枝条＜叶＜根；Na+:叶＜枝条＜根；K+:根＜叶＜枝条；Ca2+:根＜枝条＜叶.研究结果表明:Cl-、Na+进入植物体后,较大部分滞留在根部,人心果具有根系截留效应,推测其抗性方式为避盐性,研究结果还推测人心果的盐害和细胞Ca2+的自动动态平衡遭到破坏有关.

The Ion Response and the Mode of Salinity Resistance of Manilkara zapota(L.)van Royen under NaCl Stress

In order to learn the ion response and mode of salinity resistance of Manilkara zapota,the contents and distribution of 4 kinds of ions(Cl-,Na+,K+,Ca2+)in roots,branches,leaves under NaCl stress were measured.The results showed that Cl-,Na+,Ca2+ contents in M.zapota roots,branches,leaves were increased with the NaCl concentration increased,while K+ content and the ratio of K+/Na+ dropped.The Cl-content in roots,branches,leaves was 8.94 times,6.77 times,4.49 times,respectively higher than it in the control under 8‰ NaCl and Na+ content was 2.16 times,2.88 times,2.45 times,respectively.The K+/Na+ ratio in roots,branches,leaves was 0.13,0.43,0.35,respectively.The content of Cl-or Na+ was larger in roots than in branches or leaves under the same NaCl concentration.The Cl-content followed the order: branches < leaves < roots,Na+content did: leaves < branches < roots.K+ content did: roots < leaves < branch,and Ca2+ content did: roots < branches < leaves.The results showed that most Cl-,Na+ kept in roots after entering the plants.It was deduced that the mode of salinity resistance was salt avoidance for M.zapota and that the imbalance of Ca2+ related to the salt damage.