{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T06:23:51Z","timestamp":1787207031695,"version":"build-2736575974"},"reference-count":56,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T00:00:00Z","timestamp":1787184000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Plant Sci."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Humic acids (HAs) are natural organic macromolecules that play a critical role in sustainable agricultural production.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This study compared the effects of five HA productstwo lignin-based biological HAs (acid-modified, LHAac; alkali-modified, LHAal), one mineral-derived HA (MHA), one sludge-derived HA (SHA), and one commercial HA (CHA)on maize seedling growth.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>All HA treatments significantly improved root growth, photosynthetic performance, nutrient accumulation, and biomass production. Among them, MHA exhibited the strongest efficacy in promoting root proliferation and increasing specific root length, whereas SHA significantly enhanced root diameter, tissue density, and root activity. HA treatments elevated the net photosynthetic rate (Pn), relative chlorophyll content (SPAD value), and stomatal conductance (Gs) of maize seedlings, while reducing intercellular CO\u2082 concentration (Ci) in leaves. Mantel correlation analysis and variance partitioning analysis (VPA) revealed that root functional traits accounted for the largest proportion (26.7%) of the variation in seedling biomass, followed by root nutrient status (12.3%). Significant synergistic effects were also observed between photosynthetic parameters and shoot nutrient status, as well as between root-related traits and aboveground physiological indicators.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>Collectively, HAs from diverse sources improved maize seedling growth through coordinated changes in root morphology, photosynthetic activity, and nutrient utilization; root functional traits made the largest independent contribution to explaining seedling biomass variation among all measured indicators.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fpls.2026.1908981","type":"journal-article","created":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T05:28:45Z","timestamp":1787203725000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Root functional traits dominate maize seedling growth responses to different humic acids"],"prefix":"10.3389","volume":"17","author":[{"given":"Zhaolong","family":"Ding","sequence":"first","affiliation":[{"name":"Institute of Agricultural Resources and Environment, Xinjiang Academy of Agricultural Sciences","place":["Urumqi, Xinjiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruijia","family":"Guo","sequence":"additional","affiliation":[{"name":"Institute of Agricultural Resources and Environment, Xinjiang Academy of Agricultural Sciences","place":["Urumqi, Xinjiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aimaieraili","family":"Tuheti","sequence":"additional","affiliation":[{"name":"Aksu Regional Agricultural Technology Extension Center of Xinjiang Uygur Autonomous Region","place":["Aksu, Xinjiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huawei","family":"Shao","sequence":"additional","affiliation":[{"name":"Institute of Agricultural Resources and Environment, Xinjiang Academy of Agricultural Sciences","place":["Urumqi, Xinjiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chunhui","family":"Ge","sequence":"additional","affiliation":[{"name":"Institute of Agricultural Resources and Environment, Xinjiang Academy of Agricultural Sciences","place":["Urumqi, Xinjiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jifeng","family":"Zhang","sequence":"additional","affiliation":[{"name":"Institute of Agricultural Resources and Environment, Xinjiang Academy of Agricultural Sciences","place":["Urumqi, Xinjiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,8,20]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.3390\/agriculture10050147","article-title":"The effect of leonardite-derived amendments on soil microbiome structure and potato yield","volume":"10","author":"Akimbekov","year":"2020","journal-title":"Agriculture"},{"key":"B2","doi-asserted-by":"publisher","first-page":"86","DOI":"10.25252\/SE\/2025\/253726","article-title":"Humic acid and phosphate solubilizing bacteria led phosphorous bioavailability for enhancing photosynthetic efficiency and productivity of direct-seeded rice","volume":"44","author":"Ali","year":"2025","journal-title":"Soil Environ."},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.3389\/fagro.2022.848621","article-title":"Understanding the role of humic acids on crop performance and soil health","volume":"4","author":"Ampong","year":"2022","journal-title":"Front. 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