Studies Of Response Characteristics Of Eight Tree Species To Salt Stress

In this disquisition, the physiological and biochemical changes under NaClstress were studied in eight tree species and the results were summarized asfollows:The seedlings planted in salver displayed different salt tolerance among theeight tree species and the salt tolerance size is the same as the seedlings in thefield: Amygdalus persuca,Cersus pseudocerasus.Ficus carica.盐胁迫下 8 种经济林树种苗木反应特性的研究under the same stress intensity is a token for the injured degree more than forsalt tolerance. The contents of solutable sugar didn't changed, so its function isnot significant in permeability regulation. The solutable protein contents wentdown in Morus alba, rised in Zizipus jujuba and didn't change in six other treespecies . Athough some new types of protein is synthesized related to salttolerance because of salt induce, the only solutable protein contents in theleaves is not adaptive as the normal of salt tolerance. NaCl stress leaded to higher membrane permeability and the oxidation andthe POD activity was improved to relieve the membrane injury, but theprotection function of SOD is not so obvious as POD. The injuredreaction of membrane is the one which took place at high salt stress for mosttree species, but the membrane of the leaves of Zthoxylum bungeanum isexceptional for its obvious injury at low level-2‰.Namely,the membrane ofthe leaves of Zthoxylum bungeanum is very vulnerable to salt stress. The activity of NR of those tested tree species was improved except forZthoxylum bungeanum, which was reduced by NaCl stress. A large amount of Na+ entered into the root and the leaves of seedlingstreated by salt.The root is superior to the leave in the absorption of Na+ sothat the injury to the overground parts can be avoided or relieved. Thechanges of K+ are different with tree specie: Amygdalus persuca,Ficuscarica,Zizipus jujuba accelerated , Cersus pseudocerasus,Morus alba,Punnicagranatum , Zthoxylum bungeanum inhabited, and Malus spectabilischangeless.The absorption of Na+ limits K+ to enter the roots and the leavesand the lack of K+ disturbed the normal metabolism because of nutritionshortage. The global analysis indicated that the injured and adaptive reactions tookplace in all the tested tree species ,but none of them can determine the abilityof salt tolerance ultimately. The tolerance ability is a multiple p...