{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T13:27:01Z","timestamp":1787923621758,"version":"build-2784847793"},"reference-count":48,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T00:00:00Z","timestamp":1787875200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100009110","name":"Natural Science Foundation of Xinjiang Uygur Autonomous Region","doi-asserted-by":"publisher","award":["2024D01A82"],"award-info":[{"award-number":["2024D01A82"]}],"id":[{"id":"10.13039\/100009110","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Long-term excessive nitrogen application in arid cotton fields increases nitrate leaching risk during fallow and disrupts rhizosphere microecology. To clarify the cross-growth-stage regulatory effects of the biostimulant \u03b3-polyglutamic acid (\u03b3-PGA) combined with chemical fertilizer on rhizosphere microbial communities, we compared chemical fertilizer alone (NK) and \u03b3-PGA plus chemical fertilizer (GT) using rhizosphere soils collected at boll-setting (August) and fallow (October), with physicochemical measurements and metagenomic sequencing technology. At boll-setting, GT lowered pH by 0.74 units compared with NK and increased NH4+-N, NO3\u2212-N, and TN by 339.3%, 491.4%, and 23.0%, respectively. By fallow, GT increased TOC by 70.6% and maintained NH4+-N at 18.38 mg\/kg, while NK accumulated 66.85 mg\/kg NO3\u2212-N. GT buffered post-harvest fungal community disturbance (Shannon: GT 4.06 vs. NK 2.80) and shifted bacterial communities toward oligotrophic taxa and archaea toward ammonium-preferring taxa. A metagenomic LEfSe analysis showed that GT was enriched in functional genes related to [Q]: Secondary metabolite biosynthesis, transport and catabolism, [T]: Signal transduction mechanisms, and [V]: Defense mechanisms, indicating a shift from resource acquisition to conservative maintenance. Mantel tests revealed that microbial functional profiles showed the strongest association with NH4+-N (r = 0.828 in August, r = 0.883 in October, p &lt; 0.001). Thus, \u03b3-PGA with chemical fertilizer stabilizes fallow rhizosphere microbial communities, reduces nutrient leaching, and promotes carbon\u2013nitrogen co-retention.<\/jats:p>","DOI":"10.3390\/microorganisms14091905","type":"journal-article","created":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T12:27:46Z","timestamp":1787920066000},"page":"1905","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effects of Co-Application of \u03b3-Polyglutamic Acid and Chemical Fertilizer on Rhizosphere Microbial Community Structure and Function of Cotton at Different Growth Stages in an Arid Cotton Field"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-5326-1056","authenticated-orcid":false,"given":"Mingxuan","family":"Che","sequence":"first","affiliation":[{"name":"College of Life Sciences, Xinjiang Normal University, Urumqi 830017, China"},{"name":"Xinjiang Key Laboratory of Special Species Conservation and Regulatory Biology, Xinjiang Normal University, Urumqi 830017, China"},{"name":"Key Laboratory of Special Environment Biodiversity Application and Regulation in Xinjiang, Xinjiang Normal University, Urumqi 830017, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"}]},{"given":"Jingbo","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Xinjiang Normal University, Urumqi 830017, China"},{"name":"Xinjiang Key Laboratory of Special Species Conservation and Regulatory Biology, Xinjiang Normal University, Urumqi 830017, China"},{"name":"Key Laboratory of Special Environment Biodiversity Application and Regulation in Xinjiang, Xinjiang Normal University, Urumqi 830017, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Kunduziayi","family":"Kudelaiti","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Xinjiang Normal University, Urumqi 830017, China"},{"name":"Xinjiang Key Laboratory of Special Species Conservation and Regulatory Biology, Xinjiang Normal University, Urumqi 830017, China"},{"name":"Key Laboratory of Special Environment Biodiversity Application and Regulation in Xinjiang, Xinjiang Normal University, Urumqi 830017, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Jiajun","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Xinjiang Normal University, Urumqi 830017, China"},{"name":"Xinjiang Key Laboratory of Special Species Conservation and Regulatory Biology, Xinjiang Normal University, Urumqi 830017, China"},{"name":"Key Laboratory of Special Environment Biodiversity Application and Regulation in Xinjiang, Xinjiang Normal University, Urumqi 830017, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"validation","vocabulary":"credit"}]},{"given":"Yunhao","family":"Liusui","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Xinjiang Normal University, Urumqi 830017, China"},{"name":"Xinjiang Key Laboratory of Special Species Conservation and Regulatory Biology, Xinjiang Normal University, Urumqi 830017, China"},{"name":"Key Laboratory of Special Environment Biodiversity Application and Regulation in Xinjiang, Xinjiang Normal University, Urumqi 830017, China"},{"name":"College of Future Energy and Environmental Engineering, Xinjiang Normal University, Urumqi 830017, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"}]},{"given":"Zhengwu","family":"Dong","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Xinjiang Normal University, Urumqi 830017, China"},{"name":"Xinjiang Key Laboratory of Special Species Conservation and Regulatory Biology, Xinjiang Normal University, Urumqi 830017, China"},{"name":"Key Laboratory of Special Environment Biodiversity Application and Regulation in Xinjiang, Xinjiang Normal University, Urumqi 830017, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,28]]},"reference":[{"key":"ref_1","unstructured":"OECD\/FAO (2025). 9 Cotton. 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