8个高羊茅品种在上海地区的高温适应性研究OA

To address the summer survival challenges of cool-season turfgrass in the Yangtze River Delta region,this study systematically evaluated the heat tolerance of eight tall fescue(Festuca arundinacea Schreb.)cultivars under extreme high-temperature conditions in Shanghai.Principal component analysis(PCA)and other methods were used to condense the 12 indicators to three principal components.Root expansion capacity(root length,root surface area,root volume)and branching complexity(number of root tips,number of root forks)were identified as the primary indicators for assessing heat adaptation,followed by growth vigor(greenness,coverage,aboveground biomass,root-to-shoot ratio,etc.)and vertical struc-tural traits(turf height and root biomass,etc.).Based on comprehensive evaluation,the cultivars'Vertex','Police Chief',and 'Tahuo No.2' demonstrated the best heat tolerance performance.During high-temperature stress,these three cultivars showed increases of 10.72%-16.00%in coverage,3.64%-8.53%in greenness,31.75%-133.47%in aboveground biomass,and 42.41%-104.01%in root biomass compared with the poorest-performing cultivars.Moreover,their root architecture parameters showed small fluctua-tions,and turf height remained below 100 mm,exhibiting stable root development with dwarf characteris-tics.These cultivars therefore represent promising candidates for evergreen turfgrass use in Shanghai.