蒭雷草对盐胁迫的生理响应

In order to test the ability of Thuarea involuta to adapt to adversity and to reveal itsmechanism of salt tolerance, we collected samples from the tropical coral xisha dongdao island,and selected vigorous plants as the subsequent experiment materials through vegetativepropagation, which were then treated with different salt stress degree. We studied the effects oftreatments with different NaCl concentration on the contents of Malondialdehyde (MDA),antioxidase and osmotic regulator in leaves of T. involuta. Our results showed that the increase ofNaCl concentration did not accelerate the membrane lipid peroxidation of T. involuta leaf cellsunder a short term of salt treatment (28 d), but the peroxidation effect worsened with the extensionof salt treatment time and increase of NaCl concentration, which also, resluted in a graduallyrising of the content of MDA, reaching the peak at 400 mmol-1 of NaCl concentration. Under theshort term of salt stress treatment (28 d), the activity of SOD and CAT were significantlyincreased under the low (200 mmol-1) and high (400 mmol-1) NaCl concentration,respectively, the activity of POD gradually ascended with the increase of salt stress time and NaClconcentration. We discovered that under salt treatment, T. involuta accumulated SP and PRO toimprove the osmotic regulation ability, which balanced the osmotic potential inside and outsidethe cell membranes and lowered the demage of salt stress. In conclusion, T. involuta can applyboth of the antioxidant enzyme defense system and osmotic regulation mechanism under saltstress, to reduce the damage caused by lipid peroxidation of cell membrane and to easephysiological drought. In this case, we regarded the species has high salt tolerance. The results canprovide scientific foundation for artificial community construction of T. involuta, vegetationrestoration and landscaping design on South China Sea Islands, and it has great significance forsustainable development to tropical coral islands in China.