Location: Water Management and Conservation Research
Title: Hybrid bermudagrass responses to impaired water sourcesAuthor
Submitted to: HortScience
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 5/23/2023 Publication Date: 7/14/2023 Citation: Hejl, R.W., Williams, C.F., Monaco, T.A., Serba, D.D., Conley, M.M. 2023. Hybrid bermudagrass responses to impaired water sources. HortScience. 58(8):907-914. https://doi.org/10.21273/HORTSCI17206-23. DOI: https://doi.org/10.21273/HORTSCI17206-23 Interpretive Summary: Fresh water availability is a major concern for turfgrass irrigation due to diminishing surface and ground water supplies. For this reason, non-potable irrigation sources are becoming increasingly used to irrigate turfgrass areas. Unfortunately, the chemical makeup of these water sources can be of low quality, containing elements that are harmful to plants and negatively impact plant growth. As such, more information is currently needed regarding how these water sources can impact turfgrass water use, growth, and quality. Over two study periods, three hybrid bermudagrass varieties, 'TifTuf', 'Midiron', and 'Tifway', were irrigated with three irrigation water sources (reverse osmosis, local well, and recycled) at full irrigation levels to characterize evapotranspiration (ET), growth, and quality. TifTuf retained the highest visual quality and normalized difference vegetation index (NDVI) compared to both Midiron and Tifway in both tests when irrigation source and date were pooled. This was accompanied by a higher daily ET rate and significantly more shoot growth compared to Midiron. Daily ET of turfgrass receiving recycled water was 5-10% lower than those receiving the local well or reverse osmosis water. Turfgrass receiving local well water held the highest visual quality and NDVI compared to turfgrass receiving either RO or recycled water in the summer study. In the fall, turfgrass receiving RO water had lower visual quality and NDVI than turfgrasses receiving either local well or recycled water. Additionally, despite lower ETa for recycled water irrigated turfgrass in both studies, significantly higher shoot growth was observed for turfgrasses receiving recycled water compared to RO water in the summer. The findings showed that the quality of irrigation water may have an impact on crucial aspects of hybrid turf bermudagrass performance. It was also discovered that three commercially available hybrid bermudagrass cultivars varied in their ET rates, shoot growth, and turfgrass quality. Technical Abstract: Low-quality (i.e., impaired) water sources are commonly used to irrigate warm-season turfgrass landscapes due to limiting supplies of potable water sources. Currently, there is great need to define the impacts of impaired irrigation sources on turfgrass water consumption, growth, and quality. The objectives of this study were to characterize actual evaporation (ETa), growth, and quality of three hybrid bermudagrass varieties (TifTuf’, ‘Tifway’, and ‘Midiron’; (Cynodon dactylon (L.) Pers. × C. traansvalensis Burtt Davy) grown under three water sources (RO, local well, recycled), each supplied at full irrigation levels (1.0 × ETa) over two, eight-week study periods. When pooling across irrigation source and date, TifTuf maintained the highest visual quality and normalized difference vegetation index (NDVI) compared to both Midiron and Tifway, which was accompanied by a higher daily ETa rate, significantly more shoot growth, and higher water use efficiency (WUE) compared to Midiron in both studies. When pooling across variety and date, daily turfgrass ETa receiving recycled water was 5-10% less than those receiving the local well or RO water. In addition, turfgrasses receiving local well water held the highest visual quality and NDVI compared to those receiving either RO water in the summer study. Visual quality and NDVI were also lower in turfgrasses receiving RO water compared to those receiving either local well or recycled water in the fall. Despite turfgrasses having lower ETa under recycled water in both study periods, these plants had significantly higher shoot growth compared to RO water in the summer; yet, shoot growth under recycled water did not significantly differ than the other two sources in the fall study. Further, in both studies WUE was similar for turfgrasses receiving recycled water compared to 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 ET rates, quality, and shoot growth. |