Effects Of Exogenous NO And H₂S On Physiology And Biochemistry Of Festuca Arundinacea Seedlings Under Salt Stress

The content of NaCl in soil and groundwater in coastal saline alkali land is high.The salt and its content in the soil directly affect the germination of seeds,the growth of seedlings and limit the growth and yield of plants.Breeding salt tolerant plant species and improving salt resistance of plants is the key to improving salt and alkali land in biological measures.By applying exogenous substances,it is one of the feasible and effective ways to improve the salt resistance of plants.In order to clarify the physiological and biochemical changes of the seedlings of Festuca arundinacea Sodium nitroprusside?Sodium nitroprusside,SNP,NO donor?and Sodium hydrosulfide hydrate?Sodium hydrosulfide hydrate,NaHS,H₂S donor?under salt stress,explore the salt coercion mechanism of SNP and NaHS on the seedlings of Festuca arundinacea,and determine the suitable spraying concentration.In this paper,the seedlings of Festuca arundinacea in hydroponic reed were used as experimental materials.The experiments under 7 concentrations were carried out,and the suitable salt stress concentration was determined.150 mmol/L NaCl and 1/2Hoagland nutrient solution were used as control to study the Festuca arundinacea with 7 concentrations of SNP,NaHS solution and 150 mmol/L NaCl.The growth,photosynthetic characteristics,chlorophyll fluorescence characteristics,osmotic adjustment and antioxidant enzymes of seedlings were observed Research shows:?1?Under 7 different concentrations of NaCl stress,90mmol/LNaCl stressed seedlings of Festuca arundinacea seedlings were significantly damaged,and all indexes reached the maximum value.The seedlings of Festuca arundinacea seedlings were seriously damaged by150mmol/L NaCl stress,and the change was the greatest.It was suitable to simulate moderate salt stress on plant damage.Therefore,150mmol/L was selected as the concentration of NaCl for follow-up study.?2?The 100 SNP?mol/L had the most significant alleviating effect on Festuca arundinacea seedlings under 150 mmol/L NaCl stress,and the SNP alleviation effect of over250?mol/L SNP disappeared.150?mol/L NaHS had the most obvious effect on Festuca arundinacea seedlings of under the stress of 150 mmol/L NaCl,when NaHS exceed 300?mol/L,showed inhibitory effect on seedling growth and physiological and biochemical performance,and different concentrations of different concentrations showed a significant gradient effect on the remission of the seedlings of Festuca arundinacea under NaCl stress.?3?The subordination function method was used to synthetically evaluate the effect of exogenous NaCl stress on Festuca arundinacea.The comparison of 100?mol/L SNP was the most economical and effective method for alleviating the seedlings of Festuca arundinacea under 150 mmol/L NaCl compound treatment.