Font Size: a A A

Physiological Responses Of Suaeda Glauca And Helianthus Annuus Seedlings Under Salt And Alkali Stresses

Posted on:2013-12-25Degree:MasterType:Thesis
Country:ChinaCandidate:S J GengFull Text:PDF
Abstract/Summary:PDF Full Text Request
Different types of plants have different responses and mechanisms to salt and alkali stresses.In this study,we chosen an alkali-tolerant halophyte Suaeda glauca Bunge and a salt-tolerant sunflower(Helianthus annuus L.)as the test organisms,Systematic comparison of the coercive effect of salinity stress on them as well as salinity stress under two different salt and alkali tolerance mechanisms,but also the composition of the xylem fluid determination to explore the impact of salinity stress on ion transport in it.Major conclusions were as follows:1.Salt and alkali stresses leads to a sharp increase of Na + content and decrease of K+ in roots and leaves of S.glauca.Na+/K+ increased,and this a sign of plants subjected to stress.Sunflower subjected to salinity stress,Na+ content increased and K+ content decreased in root,the Na+/K+ increased as well.Na+ of Leaves did not change significantly.2.The major regulate inorganic ions in cells of S.glauca are Na+,K+ and Cl-.Osmotic adjustment of sunflower cells are Na+,K+,Cl-inside,organic acids also play a big role.3.In sunflower root main accumulation of Na+ and in leaves accumulated mainly K+under Salt and alkali stresses,while the S.glauca in the roots and leaves at the same time accumulation of Na+,K+ followed.Na+ regionalization stored in the leaves of S.glauca,while the sunflower is to minimize the transport of Na+ to aerial parts.4.A variety of organic acids were accumulation in response to salt and alkali stresses in S.glauca.Under salt stress,the main accumulation is oxalic acid and citric acid in root and oxalic acid were accumulated in the leaves;under alkaline stress,the root accumulation of citric acid and malic acid,while oxalic acid and malic acid were accumulated in leaves,while sunflower accumulated oxalic acid.5.Determination of the composition of the xylem fluid,the preliminary view that no diversion effect on ions transport through the cotyledon marks,the S.glauca salt tolerance mechanism for the regionalization of the ions,in particular,is stored in the succulent leaves,and sunflower,the cotyledon marks have diversion effect on Na+ and Cl-.In the xylem fluid of S.glauca,K+ and Na+ positive charge contribution rate were increased.Under Salt stress,In the xylem fluid of S.glauca,Cl-charge contribution rate increased and NO3-transport to the aerial parts was reduced.In xylem fluid of sunflower Na+ on the positive charge of the contribution rate was increased and K+decreased.Salt and alkali stresses had led to Cl-charge contribution rate increased the proportion of NO3-decreased in the sunflower xylem fluid.Under alkaline stress,SO42-ratio increased significantly in sunflower xylem fluid.
Keywords/Search Tags:Suaeda glauca, Helianthus annuus(sunflower), salinity stress, alkline stress, osmotic adjustment, ion balance
PDF Full Text Request
Related items