Salinity Tolerance of Kentucky Bluegrass Cultivars and Selections Using an Overhead Irrigated Screening Technique

An increasing amount of reclaimed water is being used in turfgrass management; however, reclaimed water is often high in total dissolved salts and can result in salt stress injury and poor turf quality. The objective of this study was to use an overhead irrigated greenhouse screening technique to identify Kentucky bluegrass (Poa pratensis L.) cultivars with increased salinity tolerance, using growth parameters and physiological measurements. Salt treatments were applied using an overhead sprinkler system. Twenty-four Kentucky bluegrasses and Texas bluegrass (Poa arachnifera Torr.) x Kentucky bluegrass hybrids were established in 100% sand tanks and evaluated at a control (1 dS m(-1)) and three salinity concentrations (3, 6, and 9 dS m(-1)) for a total of 10 wk. Plants were arranged in a split plot design with three replications. Percent green ratings and digital images were collected weekly and clipping weights were collected biweekly. Root and shoot weights were taken at the end of the study. Significant differences were observed between salinity treatments and cultivars. The cultivars Eagleton, Moonshadow, Fairfax, Cabernet, and Liberator exhibited the most salt tolerance, having the least decrease in growth parameters compared to the control plants (1 dS m(-1)), while cultivars Baron, A03-84, and A03-TB246 were the most salt sensitive when compared to control plants. Relative water content and photochemical efficiency were useful to quantify physiological differences between tolerant and susceptible cultivars.