Physiological responses of Brazil banana seedlings to drought stress simulated by PEG-6000

Brazil banana(Musa AAA Cavendish subgroup cv.Brazil) seedlings were taken as material,three stress strength treatments(5%,10%,15%) and three stress duration treatments(24,48,72 h) were set by using PEG-6000 to simulate drought stress environment artificially,and the changes of physiological indices of banana seedlings were studied in this paper.The results showed that the relative water content and chlorophyll content of leaf decreased significantly for different stress strength and stress duration treatment.The proline(Pro) content was presented as PEG15%PEG10%PEG5%,and Pro content of all treatments except PEG5% for 24 h were significantly higher than that of the control.The peroxidase(POD) activity was shown as PEG15%PEG10%PEG5% and the difference was significant between treatments.The POD activity of PEG5% reached the highest,the POD activity of all treatments were higher than that of the control obviously.Root vigor was reflected in PEG10%PEG15%PEG5%,the treatments of PEG5% for 24,48,72 h increased significantly compared to the control,and then the PEG5%+72 h treatment was obviously decreased,while 24 h and 48 h treatment decreased slowly.Therefore,the relative water content,chlorophyll content,Pro content,POD activity and root vigor of leaf can be used to evaluate the drought resistance of banana seedlings.