Different Heat Tolerance of Two Creeping Bentgrass Cultivars Related to Altered Accumulation of Organic Metabolites

作者：Yong Du, Yue Zhao, Zhou Li · 发表于：Agronomy · 年份：2025 · DOI：10.3390/agronomy15071544 · 被引用次数：2 · 研究领域：Turfgrass Adaptation and Management、Ruminant Nutrition and Digestive Physiology、Agriculture, Soil, Plant Science

High-temperature stress is one of the main limiting factors for the cultivation and management of cool-season creeping bentgrass (Agrostis stolonifera). The objectives of the current study were to compare physiological changes in heat-tolerant PROVIDENCE and heat-sensitive PENNEAGLE and further identify differential organic metabolites associated with thermotolerance in leaves. Two cultivars were cultivated under optimal conditions (23/19 °C) and high-temperature stress (38/33 °C) for 15 days. Heat stress significantly reduced leaf relative water content, chlorophyll content, and photochemical efficiency, and also resulted in severe oxidative damage to PROVIDENCE and PENNEAGLE. Heat-tolerant PROVIDENCE exhibited 10% less water deficit, 11% lower chlorophyll loss, and significantly lower oxidative damage as well as better cell membrane stability compared with PENNEAGLE under heat stress. Metabolomic analysis further found that PROVIDENCE accumulated more sugars (fructose, tagatose, lyxose, ribose, and 6-deoxy-D-glucose), amino acids (norleucine, allothreonine, and glycine), and other metabolites (lactic acid, ribitol, arabitol, and arbutin) than PENNEAGLE. These metabolites play positive roles in energy supply, osmotic adjustment, antioxidant, and membrane stability. Heat stress significantly decreased the accumulation of tricarboxylic acid cycle-related organic acids in two cultivars, resulting in a metabolic deficit for energy production. However, both PROVIDENCE and PENNEAG...