Effects Of Saline-Alkali Stress On Physiology,Biochemistry And Quality Of Okra

Land salinization is one of the major environmental problems in the world today,which seriously affects the growth and development of crops and restricts the development of agriculture.Therefore,it is of great significance to cultivate the crops with good economic benefits in salinealkali land and improve the utilization rate of saline-alkali land.In this study,the pot experiment was used to simulate salt stress,alkali stress and salt alkali stress(0、50、100、150、200、250 mmol/L)to plant okra.The growth and development,physiological and biochemical characteristics and fruit nutrition of okra were analyzed.The effects of salt alkali stress on the physiological and biochemical of okra were studied,which provided theoretical basis for the cultivation of Okra in saline alkali field.1.Effects of saline-alkali stress of different concentrations on the growth and development of okra.With the increase of stress concentration,the plant height,stem thickness and leaf area of Okra all showed a downward trend.Among them,the three stress concentrations of 50 mmol/L showed no significant difference compared with the control.The stress degree is salt-alkali stress>alkaline stress>salt stress.2.With the increase of stress concentration,the content of soluble protein,soluble sugar and chlorophyll in the leaves of okra at each stage showed a trend of first increasing and then decreasing.Among them,salt stress A2(100 mmol/L)and alkali stress B2(100 mmol/L)),saltalkali stress C1(50 mmol/L)can significantly increase its content.It further proves that the greater the degree of stress,the stronger the resistance of okra to adversity.The above treatments significantly increased the activities of POD,SOD,and CAT in the growth of okra,which indicated that the above three treatments improved the stress resistance of okra,and MDA gradually increased with the increase of stress concentration,among which A1,B1,C1 were different from the control Not significant.The test results show that as the stress concentration increases,the activities of POD,SOD,and CAT decrease,and the content of MDA increases.With the increase of time,the activities of POD,SOD,and CAT decrease,and the content of MDA increases.3.Salt stress A2(100 mmol/L),alkaline stress B2(100 mmol/L),and salt-alkali stress C1(50 mmol/L)can increase the content of soluble protein,soluble sugar,flavonoids,vitamin C,and fiber in the fruit.In the content of vitamins,each treatment increased compared to the control,and there was no significant difference between the treatments A1,B1,and C1 and the control.4.With the increase of stress concentration,the yield of okra decreased.Among the three stresses,the highest yield treatments were the control group,but salt stress A2(100 mmol/L),alkali stress B2(100 mmol/L),and salt-alkali stress C1(50 mmol/L)Compared with the control,the difference is not significant.The comprehensive analysis shows that the treatment A2,B2,C1 and the yield are not significantly different from the control,but the fruit quality is significantly improved.5.Combined with okra morphological indexes,physiological and biochemical indexes,comprehensive evaluation of fruit quality and yield,it can be obtained,salt stress A2(100mmol/L),alkaline stress B2(100 mmol/L),and salt-alkali stress C1(50 mmol/L)It can be used as a suitable salt-alkali level for growing okra.