Comparing cultivars of three cool-season turfgrasses for soil water NO3/\u3csup\u3e-\u3c/sup\u3e concentration and leaching potential

A field study to compare soil water NO3/--N concentration and cumulative NO3/- losses by percolation of 10 cultivars each of Kentucky bluegrass (Poa pratensis L.), perennial ryogras (Lolium perenne L.), and tall rescue (Festuca arundinacea Schreb.) was conducted at the University of Rhode Island Turfgrass Research Station, Kingston, between March 1990 and April 1992. All turf plots were established in 1985, 1986, or 1987 on an Enfield silt loam (Coarse loamy over sandy skeletal, mixed, mesic, Typic Dystrochrepts) under moderate N fertilization of 149 kg N ha-1 y-1. Soil water was collected at a depth of 60 cm to determine NO3/--N concentration and annual cumulative NO3/- losses through leaching were determined by a hydrological model which estimates soil water percolation. Significant differences among species and cultivars were identified in soil water NO3/--N concentration and NO3/- leaching potential based on monthly and seasonal analyses. These results indicate that genetic differences exist among turfgrasses for NO3/- utilization at both interspecific and intraspecific levels and suggest that a screening program could be developed to identify turfgrass cultivars having superior capacity to remove NO3/- from the soil and minimize the potential for NO3/- leaching