{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T16:52:54Z","timestamp":1785430374070,"version":"3.56.0"},"reference-count":48,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T00:00:00Z","timestamp":1781136000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Xinjiang Key Laboratory for Ecological Adaptation and Evolution of Extreme Environment Organisms, College of Life Sciences, Xiniiang Agricultural University","award":["XKLEAEEEO-07"],"award-info":[{"award-number":["XKLEAEEEO-07"]}]},{"award":["XKLEAEEEO-07"],"award-info":[{"award-number":["XKLEAEEEO-07"]}],"id":[{"id":"https:\/\/ror.org\/04qjh2h11","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Kashgar University High-Level Talent Research Start-Up Fund","award":["GCC2025ZK-008"],"award-info":[{"award-number":["GCC2025ZK-008"]}]},{"name":"Kashgar University, University-Level Innovation Team Construction Project"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Sweet sorghum, a high-quality forage and energy crop, is significantly affected by drought, the primary abiotic stress impacting its growth. Melatonin (MT) has emerged as a crucial signaling molecule in plant responses to abiotic stress. This study investigates the role of melatonin in enhancing drought tolerance in sweet sorghum, specifically using the \u2018Dali Shi\u2019 variety under polyethylene glycol (PEG)-induced drought conditions. Our findings demonstrate that exogenous melatonin application significantly increased proline content (by 27.76% and 5.95% under mild and moderate drought, respectively) while decreasing malondialdehyde (MDA) levels (by 18.33% and 35.18%, respectively). Melatonin also enhanced the accumulation of photosynthetic pigments, including chlorophyll b and total chlorophyll, and improved photosynthetic fluorescence parameters (Fv\/Fm and ETR). Additionally, melatonin treatment improved root vitality, stimulated carbon and nitrogen metabolism, and increased antioxidant enzyme activity. Transcriptomic analysis revealed that differentially expressed genes were enriched in pathways related to carbon fixation, glycolysis\/gluconeogenesis, nitrogen metabolism, antioxidant defense, and plant hormone signaling. Notably, melatonin upregulated key genes associated with these pathways and activated bHLH and MYB transcription factors. In conclusion, this study elucidates the mechanisms by which melatonin enhances sweet sorghum\u2019s drought tolerance, highlighting its potential as a practical approach for improving drought resistance in this crop.<\/jats:p>","DOI":"10.3390\/ijms27125291","type":"journal-article","created":{"date-parts":[[2026,6,12]],"date-time":"2026-06-12T06:53:10Z","timestamp":1781247190000},"page":"5291","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Melatonin Alleviates Drought Stress in Sweet Sorghum Seedlings via Protection of Photosynthetic Apparatus and Carbon-Nitrogen Metabolism"],"prefix":"10.3390","volume":"27","author":[{"given":"Nuerkaimaier","family":"Mulati","sequence":"first","affiliation":[{"name":"College of Life and Geographic Sciences, Kashi University, Kashi 844000, China"},{"name":"Key Laboratory of Biological Resources and Ecology of Pamirs Plateau in Xinjiang Uygur Autonomous Region, Kashi University, Kashi 844000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mengke","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Life and Geographic Sciences, Kashi University, Kashi 844000, China"},{"name":"Key Laboratory of Biological Resources and Ecology of Pamirs Plateau in Xinjiang Uygur Autonomous Region, Kashi University, Kashi 844000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shangfu","family":"Ren","sequence":"additional","affiliation":[{"name":"College of Life and Geographic Sciences, Kashi University, Kashi 844000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ting","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Life and Geographic Sciences, Kashi University, Kashi 844000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kun","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Life and Geographic Sciences, Kashi University, Kashi 844000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lu","family":"Li","sequence":"additional","affiliation":[{"name":"College of Life and Geographic Sciences, Kashi University, Kashi 844000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cuijie","family":"Cui","sequence":"additional","affiliation":[{"name":"College of Life and Geographic Sciences, Kashi University, Kashi 844000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Li","family":"Yu","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Xinjiang Agricultural University, Urumqi 830000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liping","family":"Zhu","sequence":"additional","affiliation":[{"name":"College of Life and Geographic Sciences, Kashi University, Kashi 844000, China"},{"name":"National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, School of Life Science, Henan University, Kaifeng 475000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Chou, J., Xian, T., Dong, W., and Xu, Y. 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