Correlation of Three Salinity Tolerance Screening Methods.

Identification of salinity tolerance in turfgrass is necessary for the successful use of alternative water sources on urban landscapes and golf courses.  Most salinity screening studies have utilized hydroponic methods to screen turfgrasses for salinity tolerance while few have incorporated field or overhead greenhouse screening methods. Little research has been done to compare the different screening methods.  The objective of this study was to correlate different field and greenhouse screening methods to determine the optimum method for salinity tolerance screening in turfgrasses.  Three different salinity screening methods were compared.  Forty perennial ryegrass (Lolium perenne L.) clones were planted in a Freehold sandy loam at the Rutgers University turfgrass research farm. Individual plants received irrigation water with salt levels equal to 10dS/m.  Clones were also planted in the greenhouse using an overhead spray chamber with 15dS/m irrigation water and sand growing media.  The final method was a hydroponic greenhouse design, using 15 dS/m irrigation water, and eight of the 40 ryegrass clones.  Visual percent green ratings were taken and correlation statistics were run on perennial ryegrass clones common to all three methods.  All three methods were highly correlated to each other: Field vs. overhead irrigated greenhouse method (r = 0.93, p = 0.0009); Field vs. hydroponic greenhouse method (r = 0.82, p = 0.0128); Overhead irrigated vs. hydroponic (r = 0.72, p = 0.0436).  Results indicate that these different screening methods should result in similar responses among plants. Researchers should consider time and labor restrictions when choosing a salinity screening method.