Comparing Growth Responses of Selected Cool-Season Turfgrasses under Salinity and Drought Stresses

Abstract

This study was conducted in a greenhouse, using hydroponics system, to compare growth responses of three cool-season turfgrass species, Creeping bentgrass (Agrostis stolonifera), Rough bluegrass (Poa trivialis), and Perennial ryegrass (Lolium sperenne) in terms of shoot and root lengths and dry matter (DM), and percent canopy green cover (%CGC) under salinity and drought stresses. Grasses were grown in Hoagland solution for 90 days prior to initiation of salinity or drought stresses. Then, 24 meq NaCl/L culture solution/day were added for each -0.1 MPa OP of salinity stress, or 75 and 119 g of PEG/L were added for -0.2 and -0.4 MPa OP of drought stress treatments, respectively. The treatments included control, -0.2 and -0.4 MPa OP salinity, -0.2 and -0.4 MPa OP drought stress. Four replications of each treatment were used in a RCB design experiment. During the stress period, grass shoots were clipped weekly for DM production, shoot and root lengths were measured, and %CGC was evaluated. The weekly clippings and the roots at the last harvest were oven dried at 60° C and DM weights were recorded. All 3 grass species were more severely affected by drought than salinity. Bluegrass was the most and bentgrass the least severely affected by either drought or salinity stress.