Salt Tolerance and K/Na Ratio of Some Introduced Forage Grass Species Under Salinity Stress in Irrigated Areas

ABSTRACTSalinity is a limiting factor for forage productivity in irrigated areas. The aim of this study was to evaluate the salt tolerance index (STI), the K/Na ratio and the forage quality of several introduced cool season grass species in irrigated agriculture. Four irrigated water salinity concentrations were used (Control, 4000, 8000 and 12000 ppm sodium chloride (NaCl)), and four grass cultivars belonging to three species were established under greenhouse conditions at the Qassim University Agricultural Research and Experimental Station during the 2012 and 2013 growing seasons [perennial ryegrass (Lolium perenne L., cvs. Aries and Quartet), endophyte-free tall fescue (Festuca arundinacea Schreb., cv. Fawn), and orchardgrass (Dactylis glomerata L., cv. Tekapo)]. A randomized complete block design (RCBD) using three replications was used. Cultivars were evaluated based on their dry weights (g m−2) and forage quality. Additionally, the STI and potassium (K+) and sodium (Na+) concentrations in the studie...