Effect of ethephon on physiological indexes of Kentucky bluegrass under drought stress

Kentucky bluegrass cultivar “Nuglade” plants were divided into two groups-ethephon treated (ETH) and non-ethephon treated control group (CK). These groups of plants were subjected to three treatment conditions: well-watered, drought, and re-watering. The effects of ethephon on the drought responses of Kentucky bluegrass were studied by measuring physiological indicators such as electrolyte leakage and chlorophyll, soluble protein, and malondialdehyde (MDA) content. Under drought stress,‘Nuglade’ treated with ethephon was able to maintain a higher leaf relative water content of 23.47% (with that of the control group being 11.5%) and lower membrane stability expressed as EL 68.1% (with that of the control group being 90.7%). During re-watering, the EL of the ethephon group recovered to that of unstressed plants. Under drought stress, the MDA content in ETH plants was lower than that in the control group. The SP content of the ETH group was also higher than that in the CK group under re-watering conditions; Our results indicated that spraying ethephon on the leaves of Kentucky bluegrass could improve performance and promote the recovery of physiological indexes during re-watering.