{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T09:24:28Z","timestamp":1787217868113,"version":"build-2736575974"},"reference-count":46,"publisher":"MDPI AG","issue":"8","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\/"}],"funder":[{"name":"Sustainable Development (SATREPS) joint project of the Japan Science and Technology Agency","award":["JPMJSA2004"],"award-info":[{"award-number":["JPMJSA2004"]}]},{"award":["JPMJSA2004"],"award-info":[{"award-number":["JPMJSA2004"]}],"id":[{"id":"https:\/\/ror.org\/00097mb19","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001691","name":"JSPS KAKENHI","doi-asserted-by":"publisher","award":["26K03122"],"award-info":[{"award-number":["26K03122"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]},{"award":["26K03122"],"award-info":[{"award-number":["26K03122"]}],"id":[{"id":"https:\/\/ror.org\/00hhkn466","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Duckweed-associated plant growth-promoting bacteria have attracted attention for their potential to enhance duckweed biomass production. However, the mechanisms underlying isolate-specific growth promotion are unclear. This study compared the effects of two duckweed-associated bacterial isolates, Terrimicrobium sp. PS02 and Aeromicrobium sp. PS05, on the growth, biomass composition, colonization behavior, and transcriptomic responses of Spirodela polyrhiza. Biomass composition and transcriptome analyses were performed to characterize the host responses. Both isolates enhanced duckweed biomass; PS02 increased it 1.2-fold, whereas PS05 induced a significant 1.4-fold increase compared to the uninoculated control. PS05 established bacterial populations approximately one order of magnitude higher than those of PS02 and formed dense extracellular polymeric substance-mediated microcolonies on the surface. Transcriptome analysis revealed that PS05 induced 1108 differentially expressed genes, compared with 454 in PS02, indicating greater host transcriptomic reprogramming. Functional enrichment of transcriptome responses showed that PS05 preferentially regulates carbohydrate biosynthesis, central carbon metabolism, and starch biosynthesis, significantly enhancing starch accumulation and turion formation without reducing protein or photosynthetic pigment content. This study provides evidence linking bacterial colonization, host transcriptomic regulation, carbon allocation, and biomass production in duckweed, offering a basis for engineering high-performance duckweed\u2013microbiome systems for sustainable biomass production.<\/jats:p>","DOI":"10.3390\/microorganisms14081850","type":"journal-article","created":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T08:10:20Z","timestamp":1787213420000},"page":"1850","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Isolate-Specific Modulation of Growth, Carbon Allocation, and Transcriptomic Responses in Spirodela polyrhiza by Duckweed-Associated Bacteria"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4889-3894","authenticated-orcid":false,"given":"Karnjana","family":"Ruenpham","sequence":"first","affiliation":[{"name":"Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 4-3-11, Takeda, Kofu 400-8511, Yamanashi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4735-5891","authenticated-orcid":false,"given":"Kazuhiro","family":"Mori","sequence":"additional","affiliation":[{"name":"Graduate Faculty of Interdisciplinary Research, University of Yamanashi, 4-3-11, Takeda, Kofu 400-8511, Yamanashi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8205-7427","authenticated-orcid":false,"given":"Yasuhiro","family":"Tanaka","sequence":"additional","affiliation":[{"name":"Graduate Faculty of Interdisciplinary Research, University of Yamanashi, 4-3-11, Takeda, Kofu 400-8511, Yamanashi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8749-0414","authenticated-orcid":false,"given":"Arinthip","family":"Thamchaipenet","sequence":"additional","affiliation":[{"name":"Department of Genetics, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand"},{"name":"Duckweed Holobiont Resource & Research Center (DHbRC), Kasetsart University, Bangkok 10900, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1547-8069","authenticated-orcid":false,"given":"Masaaki","family":"Morikawa","sequence":"additional","affiliation":[{"name":"Duckweed Holobiont Resource & Research Center (DHbRC), Kasetsart University, Bangkok 10900, Thailand"},{"name":"Division of Biosphere Science, Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810, Hokkaido, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8417-2883","authenticated-orcid":false,"given":"Tadashi","family":"Toyama","sequence":"additional","affiliation":[{"name":"Graduate Faculty of Interdisciplinary Research, University of Yamanashi, 4-3-11, Takeda, Kofu 400-8511, Yamanashi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"266","DOI":"10.1016\/j.foodchem.2016.08.116","article-title":"Nutritional value of duckweeds (Lemnaceae) as human food","volume":"217","author":"Appenroth","year":"2017","journal-title":"Food Chem."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1016\/S0304-3770(00)00131-5","article-title":"Potential and realized rates of vegetative reproduction in Spirodela polyrhiza, Lemna minor, and Wolffia borealis","volume":"70","author":"Lemon","year":"2001","journal-title":"Aquat. 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