Hybrid Bermudagrass Responses to Impaired Water Sources

Abstract

Low-quality (i.e., impaired) water sources are commonly used to irrigate warm-season turfgrass landscapes as a result of limited supplies of potable water sources. Currently, there is great need to define the impacts of impaired water sources on turfgrass water consumption, growth, and quality. The objectives of this study were to characterize actual evaporation (ETa), clipping production, and quality of three hybrid bermudagrass varieties [‘TifTuf’, ‘Tifway’, and ‘Midiron’; Cynodon dactylon (L.) Pers. × C. traansvalensis Burtt Davy] grown under three water sources [reverse osmosis (RO), local well, and recycled], each supplied at full irrigation levels (1.0 × ETa) over two 8-week study periods. When pooling across water source and date, TifTuf maintained the highest visual quality and normalized difference vegetation index (NDVI) compared with both Midiron and Tifway. This was accompanied by a greater daily ETa rate, clipping production, and water use efficiency (WUE) compared with Midiron in both studies. When pooling across variety and date, daily ETa of turfgrass receiving recycled water was 5% to 10% less than those receiving the local well or RO water. In addition, turfgrasses receiving local well water held the greatest visual quality and NDVI compared with those receiving either RO water in the summer study. Visual quality and NDVI were also less in turfgrasses receiving RO water compared with those receiving local well or recycled water in the fall. Despite turfgrasses having a lower ETa under recycled water in both study periods, these plants had significantly greater clipping production compared with RO water in the summer. Also, clipping production under recycled water did not differ significantly from the other two sources in the fall study. Furthermoe, in both studies, WUE was similar for turfgrasses receiving recycled water compared with those receiving RO or local well water. Results demonstrated that irrigation water quality influences critical factors for hybrid bermudagrass growth and that considerable variability exists among three commercially available varieties for evapotranspiration rates, quality, and clipping production.

Mowing Height Effects on ‘TifTuf’ Bermudagrass during Deficit Irrigation

“…Further, clipping production was highest for 2.5 cm turfgrass irrigated at well-watered levels and 5 cm turfgrass at the 0.65 × ETa irrigation level, compared to 7.5 cm turfgrass at deficit levels (0.3 and 0.65 × ETa) and the 10 cm turfgrass at all irrigation levels (0.3 and 1.0 × ETa) (Table 2). Increased ET a is normally accompanied by increased biomass accumulation as observed in multiple studies [32][33][34]. However, our results show a conflicting trend in which a lower ET a of grasses mowed at lower mowing heights was accompanied by an elevated shoot growth when compared to the higher mowing heights.…”

“…Further, there were three rating dates in which more clipping production occurred for turfgrass mowed at 2.5 cm compared to 7.5 cm and 10.0 cm, and multiple rating dates in which clipping production was higher for 5.0 cm mowed turfgrass compared to either 7.5 cm or 10 cm mowed turfgrass (Figure 4). Increased ETa is normally accompanied by increased biomass accumulation as observed in multiple studies [32][33][34]. However, our results show a conflicting trend in which…”