| Pot experiments were carried out to study the effects of treatment with different concentrations of seawater on growth, content and distribution of ions, accumulation of organic osmotica, damage to membrane and change of chloroplast and mitochondrion of aloe. The results were as follows.Compared with the control (treatment with Hoagland solution), there were slight decrease of the fresh weight (FW) of leaves and the total FW of aloe plant treated with 10% of seawater, while significant decline of FW of leaves and the total FW of aloe plant treated with 30% of seawater. The FW of aloe in roots and stems (RS) under 10% and 30% seawater stress were 119.5% and 105.5% of that of CK, respectively. The dry weight (DW) was improved with the rise of seawater concentration, but no significant distinction of DW between treatment with 10% and 30% of seawater, while significant increase of DW in RS in the aloe plant under 30% seawater concentration. The results showed that the yield of FW in aloe seedlings was inhibited, especially FW of leaves at higher seawater concentration. The DW of aloe treated with different concentrations of seawater had no marked difference, but accumulation of DW in RS was observed in the experiment.The Na+ content in aloe leaf and RS significantly increased among different treatments of seawater, and Na+ content of the function-leaf was less than that of other leaves. There was a significantly positive correlation between Na+ and Cl- content. With the leaf site rising and concentration of seawater increasing, the K+ content in aloe leaf (form the third leaf to seventh leaf) was reduced gradually. The K+ content of the function-leaf amount to the maximum level, SK. Na too. Ratio of Na+/K+ in the function-leaf was minor compared with that in other leaves. The value of SK, Na in RS obviously increased with seawater concentration increasing. Results also showed that the function-leaf had high ability to refuse to uptake ions under seawater stress. The RS had high selectivity for K+ relative to Na+ in the roots and stems at higher seawater concentration.Na+ in aloe plant was obviously accumulated, and its quantity accumulated was almost half of the total amount of cation concentration of leaves, RS in aloe. The percentage of Ca2+ was reduced both in leaves and RS, and the percentage of K+ in leaves (from the first leaf to fourth leaf) too. Mg2+ content keep relatively stable under seawater stress. It is suggested mat aloe had good nutrition station when exposed to seawater.The permeability of plasma increased gradually with stress time prolonging andconcentration of seawater increasing. The increasing range of permeability of plasma in the prophase treatment of the fifth and tenth day was higher than that of in the anaphase. The highest electrical conductivity of leaf was less than 30% in aloe leaf, which didn't attain lethal salt content of leaf cells. The conclusion was obtained form this study that effect on permeability of plasma membrane was not severely under seawater stress. The MDA content increased under seawater stress, The increasing range of MDA content in the anaphase was lower than that in the prophase of treatment with seawater. It was suggested that the aloe had adapted partly to seawater stress after stress of a short time.The soluble sugar and proline were very important osmoticas in aloe plant. Compared with the control, the soluble sugar content was significantly increased at the fifth day under seawater stress, and the increasing range of the soluble sugar reduced at the tenth and fifteenth day. It implied that aloe had an emergency response to seawater stress, the adaptation ability of aloe to seawater stress strengthened with the time prolonging, which caused the net increasing value of soluble sugar decreased. The proline content increased under seawater stress, and its content and increasing range were greatly increased, especially at the fifteenth day. It suggested that the two osmoticas were formed in different time under seawater stress, and maybe compensated...
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