{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,19]],"date-time":"2026-05-19T20:59:11Z","timestamp":1779224351690,"version":"3.51.4"},"reference-count":52,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,2,24]],"date-time":"2021-02-24T00:00:00Z","timestamp":1614124800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Metabolites"],"abstract":"<jats:p>Potassium (K) reduces the deleterious effects of drought stress on plants. However, this mitigation has been studied mainly in the aboveground plant pathways, while the effect of K on root-soil interactions in the underground part is still underexplored. Here, we conducted the experiments to investigate how K enhances plant resistance and tolerance to drought by controlling rhizosphere processes. Three culture methods (sand, water, and soil) evaluated two rapeseed cultivars\u2019 root morphology, root exudates, soil nutrients, and microbial community structure under different K supply levels and water conditions to construct a defensive network of the underground part. We found that K supply increased the root length and density and the organic acids secretion. The organic acids were significantly associated with the available potassium decomposition, in order of formic acid &gt; malonic acid &gt; lactic acid &gt; oxalic acid &gt; citric acid. However, the mitigation had the hormesis effect, as the appropriate range of K facilitated the morphological characteristic and physiological function of the root system with increases of supply levels, while the excessive input of K could hinder the plant growth. The positive effect of K-fertilizer on soil pH, available phosphorus and available potassium content, and microbial diversity index was more significant under the water stress. The rhizosphere nutrients and pH further promoted the microbial community development by the structural equation modeling, while the non-rhizosphere nutrients had an indirect negative effect on microbes. In short, K application could alleviate drought stress on the growth and development of plants by regulating the morphology and secretion of roots and soil ecosystems.<\/jats:p>","DOI":"10.3390\/metabo11030131","type":"journal-article","created":{"date-parts":[[2021,2,25]],"date-time":"2021-02-25T02:36:13Z","timestamp":1614220573000},"page":"131","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":121,"title":["Potassium Improves Drought Stress Tolerance in Plants by Affecting Root Morphology, Root Exudates, and Microbial Diversity"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0092-4185","authenticated-orcid":false,"given":"Qiwen","family":"Xu","sequence":"first","affiliation":[{"name":"Key Laboratory of Eco-Environments in Three Gorges Reservoir Region, College of Agronomy and Biotechnology, Southwest University, Chongqing 400715, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hao","family":"Fu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Horticulture Science for Southern Mountains Regions of Ministry of Education, College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bo","family":"Zhu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Eco-Environments in Three Gorges Reservoir Region, College of Agronomy and Biotechnology, Southwest University, Chongqing 400715, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5239-6172","authenticated-orcid":false,"given":"Hafiz Athar","family":"Hussain","sequence":"additional","affiliation":[{"name":"Key Laboratory of Eco-Environments in Three Gorges Reservoir Region, College of Agronomy and Biotechnology, Southwest University, Chongqing 400715, China"},{"name":"Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kangping","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Eco-Environments in Three Gorges Reservoir Region, College of Agronomy and Biotechnology, Southwest University, Chongqing 400715, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoqing","family":"Tian","sequence":"additional","affiliation":[{"name":"Key Laboratory of Eco-Environments in Three Gorges Reservoir Region, College of Agronomy and Biotechnology, Southwest University, Chongqing 400715, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Meichun","family":"Duan","sequence":"additional","affiliation":[{"name":"Key Laboratory of Eco-Environments in Three Gorges Reservoir Region, College of Agronomy and Biotechnology, Southwest University, Chongqing 400715, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoyu","family":"Xie","sequence":"additional","affiliation":[{"name":"Key Laboratory of Eco-Environments in Three Gorges Reservoir Region, College of Agronomy and Biotechnology, Southwest University, Chongqing 400715, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7061-1056","authenticated-orcid":false,"given":"Longchang","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Eco-Environments in Three Gorges Reservoir Region, College of Agronomy and Biotechnology, Southwest University, Chongqing 400715, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"14058","DOI":"10.1073\/pnas.1202319109","article-title":"Rapid responses of soil microorganisms improve plant fitness in novel environments","volume":"109","author":"Lau","year":"2012","journal-title":"Proc. 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