Effects Of Low Phosphorus On The Growth And Fatty Acid Content Of Suaeda Salsa

The Liaohe Estuary wetland is the junction of land and marine ecosystems,and has outstanding performance in purifying sewage and removing pollutants.In recent years,human production activities have severely degraded the wetland in the Liaohe River Estuary and Suaeda salsa which is one of its dominant species,and have caused a huge impact on the ecosystem.However,the specific reasons for the degradation of Suaeda have not been studied.In this study,the soils in the lush areas of Suaeda were collected and the inorganic phosphorus content was determined,then the results showed that the phosphorus content in the soil was at a deficient level.In order to verify whether low phosphorus in the soil has an impact on the growth and development of Suaeda,this article conducted an indoor pot experiment.The seeds of Suaeda collected from Panjin were planted after pre-germination.The experiment was set up in a normal soil group and a sterilized soil group,and set 5low-phosphorus concentration gradients,low-phosphorus treatment when the growth of Suaeda winged is consistent.In this study,the physiological indicators,photosynthesis,antioxidant enzyme activity and fatty acid content of different tissues of Suaeda were measured,and the internal relationship between Suaeda ve getation degradation and inorganic phosphorus content of the soil was explored.The results showed that low phosphorus significantly reduced the plant height,stem length,leaf number,and plant weight of Suaeda,and the growth of the plants in the normal soil group was stronger than that in the sterilized soil group;the dry weight and fresh weight were also significantly reduced,but the root-shoot ratio showed the opposite trend.Low phosphorus results in a significant decrease in photosynthetic pigment content,soluble sugar and protein content.In addition,low phosphorus leads to the disorder of Suaeda metabolism,and the content of MDA and H₂O₂increase significantly.In order to restore the intracellular balance as soon as possible,Suaeda significantly improves the activities of SOD and POD enzymes.However,the content of proline as an anti-stress marker substance did not increase.The plant’s absorption efficiency of phosphorus in the soil and the content of inorganic phosphorus in the body have been reduced,and the ATPase activity has increased significantly.Plants secrete more soil acid phosphohydrolase to increase the available phosphorus content that can be directly absorbed.This study used GC-MS technology to determine the fatty acid content in the leaves,stems and roots of Suaeda.The results showed that the types of fatty acids in different tissues of Suaeda was different,with the most in the root and the least in the stem.Low phosphorus stress caused the relative types of polyunsaturated fatty acids in the leaves of Suaeda pterosa to decrease,and the relative content of medium and long-chain fatty acids increased,but the content of fatty acids in the stem did not change significantly.Roots under low phosphorus stress reduced the production of other saturated fatty acids and enhanced the production of the unique fatty acid C18:2n6t.This paper analyzes the relationship between the degradation of Suaeda vegetation and the phosphorus content,which provides a scientific basis for the restoration and management of the wetland in the Liaohe Estuary of Panjin and the protection of Suaeda vegetation.