Effect of PEG6000 osmotic stress on physiological indexes of Neottopteris nidus (L.) J.Sm.

Under the condition of indoor simulation drought with PEG6000,the research was conduced to compare the influence of osmotic stress of PEG6000 with different concentrations on the relative water content,soluble sugar content,peroxidase(POD)activity,malondialdehyde content and free proline content of Neottopteris nidus(L.)J.Sm leaves.The results showed that the relative water content of leaf was negatively correlated with stress level.Under the treatment of various PEG6000 concentrations,the RWC would not recover even after watering.Malondialdehyde content and free proline content were both positively correlated with stress levels.After watering,malondialdehyde content of each treatment would not restore,while free proline content returned to control levels.Soluble sugars accumulated with stress time,which reached to peak value of 105.31mg/g after stressed under 20% concentration for 12 hours,and it was the main material involved in the osmotic adjustment of Neottopteris nidus(L.)J.Sm.Activity of peroxidase increased first and then decreased,lowered closely to the control group after watering.It was indicated that in adversity conditions,peroxidase(POD)of Neottopteris nidus(L.)J.Sm increased to a high-er level to relieve membrane damage,however,peroxidase(POD)could not continue to play a role when the membrane damage getting worse.Based on the analysis of the physiological indexes,we concluded that the drought-resistant ability of Neottopteris nidus(L.)J.Sm was week.The study could provide theoretical basis for the moisture management of Neottopteris nidus(L.)J.Sm.