Physiological Response Of SO₂ And CL₂ Stress On Protective Enzymes Of Acer Ginnala

Tamarix juniperina Bunge, a naturally halophyte in the northeast of China, was chosen as the experimental plant specie for this research. Four kinds of salt stresses, NaCl, Na2SO4, NaHCO3 and Na2CO3, were set up. By determining height growth and some physiological and biochemical indexes, the characteristics of physiology and biochemistry of Tamarix juniperina Bunge under four kinds of salt stresses were explored.The main results and conclusions from this experiment were showed as follows:(1) Under the four kinds of salt stress, height growth of Tamarix juniperina Bunge had been suppressed. With the salt stress enhancement, height growth of Tamarix juniperina Bunge seedings decreased accordingly.(2) With the salt stress enhancement, chlorophy II content decreased. Under NaCl, Na2SO4 and NaHCO3 stresses, the high salt content and long period of treatment caused chlorophy II content of Tamarix juniperina Bunge decreased obviously. But under the Na2CO3 stress, the low salt content and short period of treatment caused chlorophy II content of Tamarix juniperina Bunge decreased significantly.(3) Under the four kinds of salt stress, as the concentration increasing and the treatmentday prolonging, the proline content in leaves went up differently. Under the tow neutral salt (NaCl and Na2SO4) stress, the high salt content and long period of treatment caused proline content in leaves increased obviously, and that under the NaCl stress increased more obviously. Under the tow alkaline (NaHC03 and Na2CO3) stress, the low salt content and short period of treatment caused proline content increased largely, and Na2CO3 stress increased it more largely.(4) As the concentration increasing, the soluble protein content in leaves decreased. But as the treatmentday prolonging, the soluble protein content firstly increased and then decreased.(5) As the treatmentday prolonging, the soluble sugar content firstly decreased and then increased. But as the concentration increasing, the soluble sugar content changed differently, but soluble sugar contents were lower than CK. In the later period, the soluble sugar content increased.(6) Under the four kinds of salts stress, as the concentration increased and the treatmentday prolonged, the content of MDA and cellmembrane permeability in leaves of Tamarix juniperina Bunge increased diffrently. The most dramatic change was caused by Na2CO3 stress, followed by NaHCO3, NaCl and Na2SO4.(7) Under the four kinds of salts stress, in the first period of the low salt stress, as the concentration increasedand the treatmentday prolonged, SOD activity in leaves of Tamarix juniperina Bunge increased. But under the high salt stresss, as the treatmentday prolonging, the SOD activity firstly increased and then decreased.(8) In the first period of treament, the activities of POD increased as the concentration decreased; at the same salt concentration, as the treatday prolonged, the activities of POD increased firstly and then decreased.(9) Through the studies on Tamarix juniperina Bunge under the four different salts stress, it can be suggested that height growth, the content of MDA,cellmembrane permeability and the proline content could be utilized as important indexes to measure the salt-tolerance of Tamarix juniperina Bunge,but chlorophyâ…¡content, the content of soluble sugar and soluble protein,the activities of SOD and POD only could be utilized as referential indexes.(10) Under the four kinds of salts stress, according to the varieties of physiology and biochemistry characteristics, the degrees of inhibition were different, from strong to weak as follows:Na2CO3>NaHCO3>NaCl>Na2SO4.The stress intensity of alkaline salt is much stronger than that of neutral salt.