The Physiological Mechanism Of Exogenous ALA On Regulation Of Agrostis Stolonifera Under Salt Stress

Agrostis stolonifera are widely used in greening on salt soil, construction of golf and environmental transformation because of its good performance, exploring salt-tolerance species and improving salt stress of used species to expansion the planting area in the saline soil area is the work of scientific significance and practical value.Two Agrostis stolonifera,’XJ-1’(a wild germplasm collected from XinJiang Tianshan)、’L-93’(a germplasm collected from NJAU) have been evaluated for their responses to salinity and exogenous ALA in terms of physiological and biochemical indexes in salt environment and the regulation of physiological and metabolic of the two materials.The results showed that:1. Low concentration of exogenous ALA (0.5mg/L,5mg/L) can alleviate the decrease of chlorophyll contents, reduce the value of EL and MDA content,increase the activity of SOD、POD of ’L-93’ that under salt stress. High concentration of ALA (100mg/L) produced double stress.2. Salt stress can affect the metabolism of creeping bentgrass, the content of alanine, aspartic acid and other organic acids, glucose, maltose, and other monosaccharides and disaccharide significantly lower, ALA can significantly improve the content of metabolites in some plants under salt stress, such as alanine, threonine, maltose, allose sugar.3.0.5mg/LALA can promote the relative growth rate,improve chlorophyll a and b content of ’XJ-1’ and ’L-93’ under non salt environment, but had no significant effect on enzyme activity and MDA content.The damage effect on the plants of salt stress have been reduced with exogenous ALA,because its can reduced the decrease of ahlorophyll content under salt stress, reduce the MDA content and the value of EL, increased the activity of SOD、POD、CAT, improved the content of RWC.4. Salt stress significantly reduced the net photosynthetic rate of two materials, reduced the K+ content in roots and leaves and increased the excessive accumulation of Na+, reduced the selective transport of K+. Foliar application of 0.5mg/LALA can improve the Pn of two materials and reduced the excessive accumulation of Na+ in roots and leaves under salt stress.5. Compared with the two tested materials, under salt stress, the relative growth rate, net photosynthetic rate,ST value is ’XJ-1’ greater than ’L-93’, while the EL value and the Na+/K+ ratio of leaves is the latter greater than the former, indicating that the former’s tolerance to salt stress of 200mmol/L may be larger than the latter.