Monday, November 5, 2007
75-7
Long Term Performance of Cool and Warm Season Grasses Under Saline Irrigation.
Elena Sevostianova, New Mexico State University, Dept of Agronomy and Horticulture, Las Cruces, NM 88003, Bernd Leinauer, PO Box 30003, New Mexico State University, New Mexico State University, Plant Science Department, MSC 3AE, Las Cruces, NM 88003-8003, and Marcel Barrick, Skeen Hall P.O. 30003, New Mexico State University, New Mexico State University, Dept of Plant Sciences, Las Cruces, NM 88003.
A study is underway at New Mexico State University to examine the long term effects of saline ground water from sprinkler and subsurface drip irrigation on the quality of several warm and cool season grasses and on soil chemical properties of a turfgrass rootzone. Two salinity levels (0.6 dS/m and 3.1 dS/m) were applied from either sprinkler or sub-surface irrigation to seven cultivars of cool season (CS) grasses and eleven cultivars of warm season (WS) grasses. Grass quality response to salinity differed significantly between varieties and cultivars tested. Over the course of the 3 year period, seashore paspalum varieties consistently showed the highest quality under saline irrigation, followed by bermudagrasses and inland saltgrass. Zoysiagrasses performed poorest. Within the cool season grasses, only tall fescue Southeast and Tar Heel II performed somewhat acceptably under saline irrigation, with quality ratings at least occasionally of 6 or higher. Cool season grasses generally performed better under sprinkler than under drip irrigation at all water quality levels, while warm season grasses performed equally under both irrigation systems. SAR values for saline irrigated cool and warm season grasses in the top 10 cm of the rootzone did not differ significantly between both irrigation systems. SAR values increased with depth well below the zone of root penetration, suggesting a potential risk of sodium leaching into groundwater.