Relief Effects Of Acetosalicylic Acid To The Damage Of Aquatic Plants Under The Stress Of Heavy Metals

The relief effects of the acetosalicylic acid to the damage of aquatic plants Potamogeton crispus Linn, and Ceratophyllum demersum L. produced by heavy metals Cd²⁺ were measured by physiological and biochemical indexes, concentration of elements, gas chromatography as well as observations of electron microscopy. We also evaluate the effects of treatment by acetosalicylic acid to physiological indexes of Potamogeton crispus Linn. and Ceratophyllum demersum L.The results showed obvious damage to the photosynthetic systems, protective enzyme systems, antioxidant substance content, membrane systems, substance metabolism systems and cell ultrastructure of the plant by the heavy metal ion of cadmium. Resistance ability from endogenous protective enzyme systems and antioxidant substance content in the plants was enhanced by the inducement of heavy metal stress in restricted range . while defence reaction crippled as the aggravation of the injury. Acetosalicylic acid could stabilize the structure and function of the membrane and accordingly promote the growth of aquatic plants. Despite of some difference effected by acetosalicylic acid between this two kind of plants,we found that the enhancement of relative membrane penetration (RMP) by heavy metal stress was reduced, the peroxidation of membrane lipids was alleviated and to some degree protected the membrane from injury by Cd²⁺ ,thus ultimately promoted the tolerance ability of plants to heavy metal stress .As the increase of damage produced by heavy metal stress to the plants ,the relieving ability of exogenous acetosalicylic acid reduced .Under the extremely high concentration of heavy metal ions treatment, acetosalicylic acid could be of no avail.