Plant Growth Regulators and Soil Surfactants Improve Warm-Season Turfgrass Quality Under Saline Conditions.

Surfactants and plant growth regulators (PGR) are marketed as products that reduce the amount of irrigation water needed without sacrificing turf quality. A study was conducted at New Mexico State University in Las Cruces, NM during the summer and fall of 2010 to determine turf quality and drought stress of bermudagrass [Cynodon dactylon (L.)] cultivar Princess 77 and seashore paspalum [Paspalum vaginatum (Swartz)] cv. Sea Spray treated with either surfactants (Revolution or Dispatch) or a PGR (Primo MAXX) against an untreated control. Irrigation was applied daily at 50% ET₀ from either a sprinkler or a subsurface-drip system with either saline (TDS = 1600 ppm) or potable (500 ppm) water. Normalized Difference Vegetation Indices (NDVI) to assess turf stress and visual ratings to evaluate turf quality were collected bi-monthly on replicated plots from June until November. Plots treated with Primo MAXX showed  the hightest turf quality followed by those treated with Dispatch. Control plots and those treated with Revolution exhibited the lowest quality. Spectral reflectance differences were not detected. Seashore paspalum exhibited higher quality and greater NDVI readings than bermudagrass during September and October. Neither water quality nor irrigation system affected turf quality or NDVI readings throughout the research period.