Inhibition effects of salt stress on photosynthetic activity of Rumex K-1.
盐胁迫对杂交酸模叶片光合活性的抑制作用

With Rumex K-1 seedlings as test materials, this paper studied the effects of different concentration (100 -300 mmol·L-1) NaCl and KCl on their leaf photosynthetic activity and osmotic adjustment. The results showed that at the concentration of 200 mmol·L-1, NaCl had greater inhibition effect on the leaf photosynthetic activity than KCl, but at 300 mmol·L-1, the inhibition effect of KCl was much greater than NaCl. After treated with 300 mmol·L-1 of KCl and NaCl, the leaf water potential was -0.93 MPa and -1.05 MPa, and the osmotic potential was -1.43 MPa and -1.10 MPa, respectively, indicating that the increased damage caused by 300 mmol·L-1 of KCl was not from osmotic stress. Under the stress of 300 mmol KCl·L-1, the leaf Na+ concentration decreased by 88.6%, compared with the control, while the supplement of 25mmol NaCl·L-1 could obviously alleviate the damage of KCl on leaf photosynthesis, which proved that the deficit of Na+ and the accumulation of K+ in Rumex K-1 leaves could be responsible to the enhanced damage caused by 300 mmol·L-1 of KCl.