The 2022 University of Georgia (UGA) Turfgrass Research Field Day is a major event on the Turfgrass calendar and gives researchers the opportunity to showcase some of their work and findings.
Held on August 3 recently, the event also provided the chance for the university to release a number of papers and updates to research trial programs.
One such research paper examining turfgrass water use was released by the UGA at the event and details findings on improvements in drought performance of new turfgrass cultivars.
Written by Associate Professor David Jespersen and Master’s Student Ravneet Kaur, both of Crop and Soil Sciences UGA Griffin, the paper outlines the goal of the study. The ‘Water Requirements for Turfgrasses with Improved Drought Performance’ study aims to quantify the minimum water requirements of newly developed cultivars and compare them to commercially available standards.
“The ability to maintain turfgrass performance with reduced irrigation inputs or under drought conditions is a highly valuable trait,” explains the paper from the outset.
“The turfgrass industry faces many challenges, most importantly limited water resources and the desire to develop sustainable irrigation practices. A collaborative effort among turfgrass breeding programs across the southern US has been working to develop new turfgrasses with improved drought performance to meet landscape needs,” it goes on to say.
A number of breeding lines have been identified as having improved drought performance and these lines are being tested in the study to determine the minimum water requirements needed to maintain acceptable quality.
The paper describes how in the summer of 2020, plots were established under a rainout shelter structure at the UGA Griffin campus to allow control of the moisture reaching plots.
“Three replicate blocks of three cultivars were planted in the field. After establishment, irrigation was turned off in July 2021. Three times per week all plots were assessed for visual quality and signs of wilt, digital image analysis to assess percent green cover, and canopy temperature via infrared thermometry to assess transpiration,” it states.
Over the course of the trial in 2021, the paper cites that differences were seen in several measurements.
“All three bermudagrass lines, including the recently released ‘Tahoma 31’ and ‘TifTuf’, as well as an experimental line from UGA, all maintained significantly greater visual quality than ‘Tifway’ (Figure 1). ‘Tahoma 31’ and ‘TifTuf’ also maintained greater percent green cover compared to ‘Tifway’, as seen in the September 2021 measurements.“
According to the paper there was also significant differences in canopy temperatures for the experimental lines over the check varieties.
“Canopy temperatures in experimental lines were on average 2–3 °C cooler and similar trends were also seen for the total amount of applied irrigation, with these new lines requiring less irrigation and most pronounced among bermudagrass cultivars.”
The adoption of improved cultivars with reduced water requirements has the potential to greatly reduce irrigation demands and meet the needs of future sustainable turfgrass areas.
While research is ongoing, the paper concludes that to date the collected data supports that the previously identified lines have superior drought performance.
“In addition to requiring less irrigation, many lines maintained overall greater quality and had reduced canopy temperatures indicating that they were better able to extract water from the soil or otherwise regulate transpirational water loss from their leaves,” it goes on to state.
Data collection will continue through 2022 and 2023.