Dehydration tolerance rather than avoidance explains drought resistance in zoysiagrass.

Autor: Simpson E; Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC, USA., Haverroth EJ; Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC, USA., Taggart M; Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC, USA., Andrade MT; Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC, USA., Villegas DA; Centro de Tecnologías Nucleares para Ecosistemas Vulnerables, Comisión Chilena de Energía Nuclear, Santiago, Chile., Carbajal EM; Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC, USA., Oliveira LA; Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC, USA., Suchoff D; Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC, USA., Milla-Lewis S; Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC, USA., Cardoso AA; Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC, USA.
Jazyk: angličtina
Zdroj: Physiologia plantarum [Physiol Plant] 2024 Nov-Dec; Vol. 176 (6), pp. e14622.
DOI: 10.1111/ppl.14622
Abstrakt: Irrigation of grasses dominates domestic water use across the globe, and better understanding of water use and drought resistance in grasses is of undeniable importance for water conservation. Breeding programs have released cultivars with improved drought resistance, but the underlying mechanisms remain unknown. We sought to characterize the mechanisms driving drought resistance in four zoysiagrass cultivars (Lobo, Zeon, Empire, and Meyer) reported to exhibit contrasting levels of drought resistance. A dry-down was performed through deficit irrigation until 70% decline in evapotranspiration. All cultivars exhibited similar drought avoidance as they dehydrated similarly throughout the drought. Lobo and Zeon, however, exhibited a 70% decline in evapotranspiration two to three days after Empire and Meyer, thus experiencing lower water potentials. Regarding drought tolerance, Lobo and Zeon maintained higher normalized difference vegetation index (NDVI) and lower perceived canopy mortality at higher dehydration levels than Empire and Meyer. We use "perceived" because visual assessments of canopy mortality are influenced by drought-induced leaf rolling. During the recovery, leaves rehydrated and unrolled, so the "actual" canopy mortality could be evaluated. All cultivars exhibited similar mortality on the first recovery day despite Lobo and Zeon experiencing more severe dehydration. Throughout the recovery, Lobo and Empire exhibited faster re-growth and showed the lowest canopy mortality, and Lobo exhibited the highest NDVI. The improved drought resistance of Lobo and Zeon results from greater dehydration tolerance rather than avoidance. This study has implications for lawn owners selecting the best cultivars and for breeding programs aiming at improving drought resistance of zoysiagrasses.
(© 2024 The Author(s). Physiologia Plantarum published by John Wiley & Sons Ltd on behalf of Scandinavian Plant Physiology Society.)
Databáze: MEDLINE
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