In order to explore the alleviation effect of exogenous plant growth regulators （ PGRs ） on the growth of reed canarygrass （Phalaris arundinacea L.）under salt， waterlogging and salt-waterlogging combined stress， reed canarygrass at tillering stage was used as material， and different concentrations of ethephon （ETH）， indole-3-acetic acid （IAA）， spermidine （Spd） and γ-aminobutyric acid （GABA） were applied under three stresses， and the related physiological indexes were determined. The results showed that all three stresses significantly inhibited the growth of reed canarygrass， and the application of PGRs could effectively alleviate the stress damage. Among them， the application of 80 mg·L^-1 ETH under salt stress had the best mitigation effect， the Pro content was significantly increased by 20.36% and the MDA content was decreased by 34.52% compared with the stress group. Under flooding stress， 60 mg·L^-1 ETH was the best， and the activities of SOD and CAT were significantly increased by 105.83% and 40.07%， respectively. Under combined stress， 10 mmol·L^-1 GABA had the best effect， chlorophyll content increased by 30.30%， MDA decreased by 43.75%， and CAT increased by 23.31%（P<0.05）. In summary， the application of PGRs can alleviate stress damage by enhancing osmotic adjustment and antioxidant capacity and reducing membrane lipid peroxidation， and the type and concentration of optimal regulators vary depending on the type of stress.

Plant growth regulators （PGRs）  /  Phalaris arundinacea L.  /  Salt stress  /  Waterlogging stress  /  Salt-waterlogging combined stress