{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T05:02:32Z","timestamp":1789448552217,"version":"build-2803163510"},"reference-count":30,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,13]],"date-time":"2026-09-13T00:00:00Z","timestamp":1789257600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012190","name":"Ministry of Science and Higher Education of the Russian Federation","doi-asserted-by":"crossref","award":["075-15-2025-473"],"award-info":[{"award-number":["075-15-2025-473"]}],"id":[{"id":"10.13039\/501100012190","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Plants"],"abstract":"<jats:p>Bacillus subtilis is one of the most widely used plant growth-promoting bacteria (PGPB), but the optimal method and timing of its application under abiotic stress have not been systematically compared across different stress types within a single experimental framework. Here, we evaluated the effect of B. subtilis strain GMG1288 on spring wheat (Triticum aestivum L.) under three abiotic stresses\u2014soil salinity, PEG-induced osmotic stress, and heavy metal contamination\u2014comparing 13 application variants (seed inoculation, and single or multiple watering with the bacterial suspension) applied at different time points in a 6-week pot experiment, alongside in vitro characterization of strain GMG1288. Two-way ANOVA showed that stress type was the dominant source of variability in wheat growth parameters, while application method and timing were significant but weaker, stress-dependent modifiers. Under salinity, seed inoculation was the key determinant of root mass gain; under osmotic stress, application timing was decisive, with efficacy confined to a narrow window at stress onset (days 14\u201321); under heavy metal stress, only repeated watering produced a consistent effect, while single applications and inoculation showed no reliable benefit. These results indicate that the effective application regimen for B. subtilis GMG1288 is stress-specific rather than universal, and suggest that application strategies for PGPB-based biological products should be guided by strain-specific phenotypic activity profiles rather than by generic method\/timing schemes.<\/jats:p>","DOI":"10.3390\/plants15182806","type":"journal-article","created":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T09:34:01Z","timestamp":1789378441000},"page":"2806","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Growth-Promoting Potential of Bacillus subtilis GMG1288 in Wheat Under Abiotic Stress: Effects of Application Method and Timing"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4852-5661","authenticated-orcid":false,"given":"Ekaterina Alexeevna","family":"Sokolova","sequence":"first","affiliation":[{"name":"Knorre Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2746-2307","authenticated-orcid":false,"given":"Evgeniya Vladimirovna","family":"Chumanova","sequence":"additional","affiliation":[{"name":"Knorre Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"}]},{"given":"Irina Nikolaevna","family":"Tromenschleger","sequence":"additional","affiliation":[{"name":"Knorre Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3405-6980","authenticated-orcid":false,"given":"Elena Nikolaevna","family":"Voronina","sequence":"additional","affiliation":[{"name":"Knorre Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Sharma, K., and Kumar Sharma, P. 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