Research On The Physiological-Ecological Mechanism Of Salt Tolerance In Haloxylon Ammodendron Seedling

Haloxylon ammodendron belongs to Chenopodiaceae,it is one of drought resistance brush or small trees. It mainly distributed in arid-desert areas of northwest in China,it has strong tolerance to the drought stress,salt stress,wind erosion stress. In order to study the physical mecanism of Haloxylon ammodendron seedlings under the salt stress,two kinds of sodium(NaCl and Na2SO4)with different salinity were used in this experiment.It was mensurated all physiological index of the Haloxylon ammodendron seedling which threatened by different salinity for a long time. It indicated that,when salinity increase and coercion time extension,the fresh weight,the dry weight,the succulent,the water content,the chlorophyll of Haloxylon ammodendron seedling showed decrease tendency under two kinds of salty coercion. The membrane penetrability,the malondiadehyde of Haloxylon ammodendron seedling present , the trend of escalation. The activity SOD and POD performation increased earlier and decreased later. The CAT content presented the trend of escalation,and risen quickly at first but risen slowly later;it explained that CAT risen later than SOD and POD. The proline content presented significant trend of escalation. The soluble sugar was stable in earlier period and changes obvious in later period. The starch content performed increase earlier and decrease later with threat of salinity for a long time.. The soluble protein content decreased with salinity coercion for a long time.There was a positive correlation between membrane permeability and malondiadehyde after analysis of correlation. membrane permeability and malondiadehyde were gradually increasing with the salt concentration's growing and stress time's extending,there was a positive correlation between SOD and POD;there was a negative correlation between starch and sugar;there was a negative correlation between soluble protein and praline...