2017 ASHS Annual Conference

Increasing salinity issues caused by insufficient precipitation, drought, and increasing use of alternative non-potable sources of irrigation water are a major concern for turf management in the southwestern United States. Modification of soil physicochemical properties that result from salinity is one means of alleviating plant salinity stress. However, turf managers are inundated with a plethora of salinity alleviation products, many of which have not been tested under non-biased, replicated experiments on turf. The objective of this study was to evaluate six commercial products or programs for alleviating soil salinity and stress on ‘Tifway II’ hybrid bermudagrass [Cynodon dactylon (L.) Pers. x Cynodon transvaalensis Burtt-Davy] irrigated with saline water (electrical conductivity = EC ≈ 4.4 dS/m). The study was conducted in 2013 and 2014 at the University of California, Riverside turfgrass research facility in Riverside. Six commercial programs included: [CrossOver (Numerator Technologies, Sarasota, FL) (calcium silicate, magnesium silicate, and Monosilicic acid); Revert (polyalkylene glycole); SUNBurst Cal Plus 8% (Westbridge Agricultural Products, Vista, CA) (calcium carbonate and calcium nitrate); a combination of DeSal (carboxylic acid), and Stress Rx (potassium nitrate, potassium acetate, and calcium nitrate) and XP Micro (Ocean Organics, Ann Arbor, MI) (urea, magnesium nitrate, manganese nitrate, manganese sulfate, ferrous sulfate, iron EDTA, kelp extract); and Turfcare Natural Plant Nutrient (Gantec Incorporation, Midland, MI) (Meliaceae spp. extracts)]. Every two weeks and in between treatment applications, plots were evaluated for visual turf quality, and dark green color index and percent green cover using Digital Image Analysis. Leachate was also collected and analyzed for electrical conductivity on the same day. Replicate soil samples were collected and analyzed for salinity and nutrients at the end of each growing season. Higher evapotranspiration (ET) rates in 2014 exacerbated the effect of salt stress, but no turf loss occurred throughout the study. DeSal in combination with Stress Rx, and XP Micro was the only treatment that resulted in acceptable turf quality and decreased Sodium Adsorption Ratio and sodium content in the rootzone.