Turfgrass establishment and maintenance under deficit irrirgation and saline soil conditions

In arid and semi-arid regions, such as New Mexico, turfgrass water consumption is a major point of political debate. A two-year study has determined whether it is possible to establish warm-season turfgrasses irrigated with saline water using either sprinklers or subsurface drip. Bermudagrass [Cynodon dactylon (L.)] and seashore paspalum [Paspalum vaginatum (Swartz)] were seeded either in March (dormant) or June (traditional). Grasses that were seeded early established faster and reached greater ground cover at the end of both growing seasons. Sprinkler-irrigated plots showed greater ground cover in comparison to drip-irrigated plots at the end of both establishment periods. Higher salinity levels were found in subsurface drip irrigated plots at the end of the growing periods.;Subsurface capillary irrigation (SCI), drip lines surrounded by a patented membrane, is purported to conserve irrigation water by applying water more evenly and efficiently. A study was conducted at New Mexico State University from 2009 to 2011 to investigate the establishment of tall fescue [ Festuca arundinacea (L.)] and Kentucky bluegrass [Poa pratensis (L.)] irrigated using either SCI or a sprinkler irrigation system in combination with saline or potable water. Capillary-irrigated plots reached 75% ground cover as fast as sprinkler-irrigated ones in 2010 but were slower in 2011. Results suggest that SCI can be used to establish cool-season turfgrasses, however grow-in of subsurface irrigated turf can be delayed when compared to sprinkler-irrigated plots. Results also revealed that SCI is more prone to salinity build-up in the root zone than sprinkler irrigation.;A third study was conducted to investigate the effect of drought stress on bermudagrass and seashore paspalum treated with either soil surfactants (Revolution or Dispatch) or a plant growth regulator [Trinexapac-ethyl (TE)]. Irrigation was applied daily at 50% reference evapotranspiration from either a sprinkler or a subsurface-drip system with either saline or potable water. Applications of TE resulted in greater turf quality and increased pigment content and antioxidant activity. At the end of the study SDI plots showed higher quality and pigment content compared to sprinkler plots. Salinity had no detrimental effect on turf quality or physiology.