Effects of Mixed Saline-Alkaline Conditions on Turfgrass Quality and Vegetative Growth.

Saline and alkaline (i.e. high pH) conditions often coexist in nature. In this research, five cool-season grasses, tall fescue (Festuca arundinacea), Kentucky bluegrass (Poa pratensis), creeping bentgrass (Agrostis palustris), perennial ryegrass (Lolium perenne), and alkaligrass (Puccinellia distans) were grown under control (non-saline) and four saline-alkaline conditions [2 salinity concentrations (5 - 16 dS m^-1) x 2 pH levels (8.0 - 9.5)] in a hydroponic system. Turfgrass visual quality and relative growth rate decreased with an increasing salinity level, while alkalinity showed limited impact on turfgrass growth and performance. Alkaligrass and Kentucky bluegrass showed the highest and lowest quality and vegetative growth of all the grasses under saline-alkaline stress. The results suggested that salinity plays a more important role than alkalinity under the combined saline-alkaline conditions. Turfgrass managers may use high salt-tolerant turf when facing saline-alkaline stress.