17 Xin Du Ping Deng Yang Luo Tajie Sangzhu Manjun Yang Journal of Animal and Plant Sciences JAPS 20252025/06/26 35 3 873-889 1018-7081 https://doi.org/10.36899/JAPS.2025.3.0076 <p>Annual ryegrass (<em>Lolium multiflorum</em> Lam.) cultivars, including Angus No.1, Abundant, Bolt, Jumbo, Tetragold, Barwoltra, and Diamond T, are widely cultivated in China for forage production. However, drought stress severely limits their yield and quality. This study investigated the drought tolerance mechanisms of these cultivars under 14-day extreme drought conditions. Physio-biochemical parameters, including chlorophyll content, osmoprotectants (saccharides, free amino acids, ascorbic acid), antioxidants (glutathione, polyphenols), oxidative damage markers (malondialdehyde (MDA), reactive oxygen species (ROS), superoxide anion), and structural components (cellulose, hemicellulose, lignin), were analyzed. This research found that Bolt exhibited superior drought tolerance, maintaining higher chlorophyll A (1.93 &plusmn; 0.035 mg/g), total chlorophyll (3.17 &plusmn; 0.065 mg/g), ascorbic acid (1885.9 &plusmn; 117.8&mu;Mol/g), and glutathione (234.2 &plusmn; 25.69 &mu;g/g) compared to other cultivars. Additionally, Bolt showed enhanced hemicellulose accumulation (241.3 &plusmn; 3.21 mg/g) and minimal reduction in cellulose. Despite elevated MDA (13.93 &plusmn; 1.1nMol/g) and ROS (119,000 &plusmn; 4,000 relative fluorescence units (RFU)/g), Bolt&rsquo;s robust antioxidant system and structural adaptations likely mitigated oxidative damage. Re-watering experiments confirmed Bolt&rsquo;s resilience, underscoring its suitability for cultivation in arid areas. These results provide critical insights into selecting drought-tolerant ryegrass varieties for sustainable forage production in China.</p> Lolium multiflorum, Drought stress, Antioxidants, Osmoprotectants, Cell wall components Pakistan Agricultural Scientists Forum https://thejaps.org.pk/AbstractView.aspx?mid=2024-JAPS-2626