Salt Tolerance Screening of 74 Cool-Season Turfgrass Cultivars in Solution Culture.

Turfgrass is often subject to significant salt stress as a result of poor water quality, insufficient leaching, or exposure to environmental contaminants. Establishment of salt tolerant turfgrass cultivars is one possible method of mediating the effects of salts in irrigation water or the soil environment. As such, the objective of this research was to evaluate the salt tolerance of improved turfgrass cultivars in a controlled environment using digital image analysis. Two tubs were filled with 760 L of half-strength Hoagland solution. Three replications of 74 cool-season turfgrass cultivars were seeded at recommended seeding rates in 10.16 cm x 10.16 cm pots of silica sand and suspended in each tub in a randomized complete block design. Pots were established in a greenhouse for 12 weeks, beginning in fall 2010, and the experiment was repeated during summer 2011. Following a control treatment period, all pots were exposed to 4 dS m^-1, 14 dS m^-1, and 24 dS m^-1 successively, each for two weeks. Digital images were collected at the end of each treatment level using a custom light box designed to fit over the pots, and analyzed for percent green tissue. Cultivars of tall fescue (Festuca arundinacea Schreb.) were found to be most salt tolerant with 'Wolfpack II' and 'Jaguar 4G' performing best at the 14 dS m^-1 and 24 dS m^-1 treatment levels, respectively. Numerous fine fescue entries also performed well including slender creeping red fescues (Festuca rubra L. ssp. litoralis) 'Sealink', 'Seabreeze GT', and 'Shoreline'. Cultivars found to have consistent salt tolerance at all levels may be used to guide recommendations for turfgrass managers and breeders and have potential for use in salt-tolerant mixtures.