Studied On Salt Resistance Of Atriplex Canes Cens In Zhang Ye Area

The experiment studied Salt-tolerant Mechanism on Atriplex canes cens , Tamarix ramosissima and Haloxylon ammodendron systematically. Fifteen indices were tested including the followings: survivalrate, free Proline,solube sugar,soluble proteins, Na+content , K~+ content, membrane permeability, MDA content, SOD activity, POD activity,CAT activity, Chlorophyll,net photosynthetic rate, transpiration rate and stomatal conductance,in order to find out inherent mechanisms of salt tolerance of the three kinds of shrubs and provide theoretics basis of introduction of Atriplex canes cens in zhang ye area.The results showed that:(1) The survivalrate investigation showed that :the survivalrate decreased with the salt stress.the survivalrate of Atriplex canes cens was higher than the other species,so Atriplex canes cens had better salt resistance.(2)In this experiment, During the process of salt stress, the change of Soluble proteins which is one of the Osmoregulation substance is significant,however,the changes of free Proline content and the Soluble sugar were not significant., the Na+content of Atriplex canes cens was less than Tamarix ramosissima and Haloxylon ammodendron.and the K+content of Atriplex canescens more than Tamarix ramosissima and Haloxylon ammodendron. So from the angle ofOsmoregulation substance, Atriplex canescens had better salt resistance.(3) During the process of salts stress,stability and the completeness of cell membrane system were damaged, losing the choice to the ions ,and pernicious ions greats quantity were absorbed. It is the main reason of the great quantity of plant that cell membrane system were seriously damaged in high salt stress treatment.The membrane permeability of Atriplex canes cens was less than the other species,so the membrane injury was less than the other species.(4) During the process of salts stress,the SOD,POD activities increased first ,then decreased. The range of variation of Tamarix ramosissima was larger than Atriplex canes cens and Haloxylon ammodendron. SOD,CAT, POD can clean out oxygen free radical timely under low salt tolerance. But during the process of high salt stress ,SOD, CAT, POD activity were deactivated,activity lost and damaged,which causes the membrane system instable. At the same time,the activities of Enzyme in the body of plants were related with themself.(5) During the process of salts stress, photosynthetic rate and stomatal conductance was very sensitive to salts stress, they were different between low salt tolerance and high salt stress.The stability of Chlorophyll in Tamarix ramosissima and Haloxylon ammodendron was not as good as Atriplex canes cens, and the photosynthetic rate of Atriplex canes cens decreased more than Haloxylon ammodendron,but less than Tamarix ramosissima.(6) The primary component analysis indicates:The primary components of Tamarix ramosissima were MDA, membrane permeability, stomatal conductance , net transpiration rate , solube sugar, soluble proteins. The primary components of Atriplex canes cens were net photosynthetic rate, stomatal conductance, transpiration rate ,MDA. The primary components of Haloxylon ammodendron were MDA, K+content,chlorophyll content,SODactivity ,PODactivity, solube proline.(7) Applying the method of Fuzzy integrative evaluation to evaluated the salt tolerance of the three kinds of shrubs ,the result showed that the Atriplex canes cens > Tamarix ramosissima lour > Haloxylon ammodendron .Evaluating the tolerance of the three kinds of shrubs,we can make the conclusion as follow: Atriplex canescen can be introducted as a excellent breed variety of salt tolerance in Zhang ye area.