{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T09:24:18Z","timestamp":1787304258941,"version":"build-2736575974"},"reference-count":47,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T00:00:00Z","timestamp":1787270400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Guizhou Provincial Basic Research Program (Natural Science), General Program","award":["QKHJC-MS [2026] 740"],"award-info":[{"award-number":["QKHJC-MS [2026] 740"]}]},{"name":"Jinchang Comprehensive Experimental Station of the National Forage Industry System","award":["CARS-34-44"],"award-info":[{"award-number":["CARS-34-44"]}]},{"award":["CARS-34-44"],"award-info":[{"award-number":["CARS-34-44"]}],"id":[{"id":"https:\/\/ror.org\/01pvt8a36","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Gansu Agricultural University Publicly Funded Doctoral Research Start-up Fund Project","award":["225005"],"award-info":[{"award-number":["225005"]}]},{"award":["225005"],"award-info":[{"award-number":["225005"]}],"id":[{"id":"https:\/\/ror.org\/05ym42410","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antioxidants"],"abstract":"<jats:p>This study investigated the effects of Sinorhizobium meliloti GAU-93 inoculation on the growth and drought responses of alfalfa (Medicago sativa L.). Alfalfa seeds were inoculated with the GAU-93 strain Sinorhizobium meliloti and subjected to four soil water content levels: 15% (severe drought), 30% (moderate drought), 45% (well-watered control), and 60% (high-moisture condition). Various growth parameters, antioxidant enzyme activities, flavonoid-related traits, and membrane lipid peroxidation were measured. Increasing drought severity reduced plant growth, fresh and dry biomass, and relative water content (RWC). GAU-93 inoculation was associated with smaller reductions in these traits across several water regimes. Inoculated plants also showed higher flavonoid contents and higher expression of several flavonoid biosynthetic genes, including CHS, DFR, F3H, and PAL. In addition, GAU-93 was associated with lower membrane lipid peroxidation and higher antioxidant enzyme activities. Overall, these findings suggest that Sinorhizobium meliloti GAU-93 may help alleviate drought-induced oxidative stress and support alfalfa growth under the tested water regimes. This study provides a basis for further evaluation of GAU-93 as a microbial strategy to improve drought tolerance in forage crops.<\/jats:p>","DOI":"10.3390\/antiox15081040","type":"journal-article","created":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T08:14:01Z","timestamp":1787300041000},"page":"1040","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Sinorhizobium meliloti GAU-93 Inoculation Is Associated with Reduced Drought-Induced Oxidative Damage and Enhanced Flavonoid Accumulation and Antioxidant Capacity in Alfalfa"],"prefix":"10.3390","volume":"15","author":[{"given":"Xiaohu","family":"Wang","sequence":"first","affiliation":[{"name":"Pratacultural College, Gansu Agricultural University, Lanzhou 730070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jianhong","family":"Li","sequence":"additional","affiliation":[{"name":"School of Biological Sciences and Technology, Liupanshui Normal University, Liupanshui 553004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuelian","family":"Cui","sequence":"additional","affiliation":[{"name":"Pratacultural College, Gansu Agricultural University, Lanzhou 730070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Long","family":"Chen","sequence":"additional","affiliation":[{"name":"Lanzhou Honggu District Science and Education Promoting Agriculture Demonstration Park Management Center, Lanzhou 730084, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Changning","family":"Li","sequence":"additional","affiliation":[{"name":"Pratacultural College, Gansu Agricultural University, Lanzhou 730070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shuai","family":"Wang","sequence":"additional","affiliation":[{"name":"Pratacultural College, Gansu Agricultural University, Lanzhou 730070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tuo","family":"Yao","sequence":"additional","affiliation":[{"name":"Pratacultural College, Gansu Agricultural University, Lanzhou 730070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e1651183","DOI":"10.1080\/15592324.2019.1651183","article-title":"Salicylic acid regulates polyamine biosynthesis during drought responses in oat","volume":"14","author":"Canales","year":"2019","journal-title":"Plant Signal. 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