Turfgrass Physiology Associated With Drought Performance

Summary

University of Georgia scientists are researching underlying mechanisms responsible for improved drought performance in warm-season turfgrasses.

Situation

Turfgrasses provide many important benefits to society, including functional, aesthetic, and environmental functions. However, during periods of drought turfgrasses often experience water stress resulting in damage to turf areas. Competition for limited fresh water resources, and an increased desire by consumers to have turfgrasses which require fewer inputs, means that the development of turfgrasses able to withstand droughts are a major goal to meet the demands of current and future turf areas. Drought stress is a complicated abiotic stress that affect many aspects of plant metabolism and is ultimately dependent on both environmental conditions and plant responses. Due to this complexity, understanding the underlying traits responsible for improved drought performance is essential to the development of improved cultivars and management of turfgrass under stressful conditions.

Response

Turfgrass scientists at the University of Georgia are researching the underlying mechanisms responsible for drought tolerance in warm-season turfgrasses. These sets of experiments are conducted across a wide range of conditions, from controlled environment growth chambers where experimental conditions can be precisely controlled, to field studies which more accurately represent the complex interactions between plant and environment. Physiological measurements of plant responses to drought are being taken to look at multiple facets responsible for a plants overall response to water stress, with examples including water-use rates, rooting depth and volume, and activities of antioxidant enzymes involved in plant defense. Since a plant’s overall drought performance is dependent on the combination of many factors, by looking at multiple factors we hope to determine which are playing the most important role in a given cultivar. This is particularly important for experimental lines developed from breeding programs since it gives a more detailed picture of why there are differences in drought performance among plants. This underlying physiological information results in a better understanding of which traits need to be better integrated into future cultivars and how to best screen for these traits.

Impact

We have screened experimental breeding lines and commercial cultivars for physiological differences under drought conditions. These experiments have been performed in bermudagrass (Cynodon spp.), zoysiagrass (Zoysia spp.) , and seashore paspalum (Paspalum vaginatum). These turfgrass species are some of the most economically important and widely used in the state of Georgia, being found on home lawns, sport fields, parks, and golf courses. While these efforts are ongoing important traits involved in improved drought responses have been identified. Examples include zoysiagrasses that were able to maximize water uptake through deep root systems and quickly respond to drought to minimize water loss from the canopy maintained the greatest quality. In bermudgrass, the accumulation of protective solutes was identified as an important drought response, and in seashore paspalum top performing lines were found to better maintain photosynthesis further into periods of drought. Additionally, these trials have helped identify several lines developed by plant breeders at the University of Georgia that have exceptional drought performance compared to commercially available cultivars. This information will lead to improved screening and selection for drought tolerance grasses, ultimately allowing for low-input lawns to help conserve water.

State Issue

Sustainability, Conservation, & the Environment

Details

• Year: 2020
• Geographic Scope: Multi-State/Regional
• County: Spalding
• Location: Georgia Station, Griffin
• Program Areas:
  • Agriculture & Natural Resources