{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,16]],"date-time":"2026-01-16T17:40:37Z","timestamp":1768585237838,"version":"3.49.0"},"reference-count":36,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2025,10,31]],"date-time":"2025-10-31T00:00:00Z","timestamp":1761868800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Committee of Science of the Ministry of Science and Higher Education of the Republic of Kazakhstan","award":["BR21881942"],"award-info":[{"award-number":["BR21881942"]}]},{"DOI":"10.13039\/501100012190","name":"Ministry of Science and Higher Education of the Russian Federation","doi-asserted-by":"publisher","award":["075-15-2025-663"],"award-info":[{"award-number":["075-15-2025-663"]}],"id":[{"id":"10.13039\/501100012190","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Salicylic acid (SA) is a key phytohormone that coordinates plant innate immunity and systemic acquired resistance. Because SA levels and signaling are highly dynamic in space and time, a suite of SA-focused tools, including SA-specific microbial biosensors and SA-responsive transcriptional and chemical reporters, has been developed to study them. This review compares three classes of tools in terms of sensitivity, specificity, temporal resolution, invasiveness, quantifiability, and suitability across species. We describe developing genetically encoded sensors that can directly sense salicylic acid and report it, for example, via a fluorescence resonance energy transfer signal or another real-time output. We offer recommendations on method selection by research goal and plant species, as well as combined protocols (long-term autoluminescence plus local probes\/biosensors) for cross-validation. Future work should prioritize substrate-free, quantitative SA reporters deployable in crops and the field; coupled with CRISPR-based editing and screening, these tools would enable reporter-guided discovery of immunity genes and rapid engineering of durable disease resistance.<\/jats:p>","DOI":"10.3390\/ijms262110610","type":"journal-article","created":{"date-parts":[[2025,11,3]],"date-time":"2025-11-03T13:15:14Z","timestamp":1762175714000},"page":"10610","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Strengths and Limitations of Salicylic Acid Reporters"],"prefix":"10.3390","volume":"26","author":[{"given":"Viktor V.","family":"Morozov","sequence":"first","affiliation":[{"name":"Shemyakin\u2013Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2558-2476","authenticated-orcid":false,"given":"Ilia V.","family":"Yampolsky","sequence":"additional","affiliation":[{"name":"Shemyakin\u2013Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia"},{"name":"Institute of Translational Medicine, Pirogov Russian National Research Medical University, Ostrovityanova 1, 117997 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5204-4377","authenticated-orcid":false,"given":"Bulat K.","family":"Iskakov","sequence":"additional","affiliation":[{"name":"Aitkhozhin Institute of Molecular Biology and Biochemistry, Science Committee Ministry of Science and Higher Education, 050012 Almaty, Kazakhstan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1188-211X","authenticated-orcid":false,"given":"Anastasia V.","family":"Balakireva","sequence":"additional","affiliation":[{"name":"Shemyakin\u2013Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1093\/pcp\/pcx181","article-title":"Salicylic Acid and Jasmonic Acid Pathways Are Activated in Spatially Different Domains Around the Infection Site During Effector-Triggered Immunity in Arabidopsis Thaliana","volume":"59","author":"Betsuyaku","year":"2017","journal-title":"Plant Cell Physiol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1073","DOI":"10.1111\/j.1365-313X.2006.02758.x","article-title":"Quantitative in Situ Assay of Salicylic Acid in Tobacco Leaves Using a Genetically Modified Biosensor Strain of Acinetobacter Sp. 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