{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T23:57:32Z","timestamp":1792540652605,"version":"4.5.0"},"reference-count":49,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2024,6,26]],"date-time":"2024-06-26T00:00:00Z","timestamp":1719360000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004488","name":"Croatian Science Foundation","doi-asserted-by":"publisher","award":["UIP-2020-02-7413"],"award-info":[{"award-number":["UIP-2020-02-7413"]}],"id":[{"id":"10.13039\/501100004488","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Olive knot disease, caused by the bacterium Pseudomonas\u00a0savastanoi pv. savastanoi, causes great damage in olive orchards. While control measures of P.\u00a0savastanoi pv. savastanoi in olive orchards primarily rely on pruning and copper-based treatments, the use of antibiotics as bactericidal preparations in agriculture is limited and highly restricted. However, plants are naturally endowed with protective molecules, such as phenolic compounds, which defend them against herbivores, insects, and microorganisms. This research aimed to test the virulence of five strains of P. savastanoi pv. savastanoi isolated from different growing regions and olive varieties, and to examine whether there is a difference in plant susceptibility based on the variety. An additional goal was to test the antimicrobial activity of olive mill wastewater, known for its high content of phenolic compounds, and aqueous garlic hydrolysate, as well as to compare them with a commercial copper-based product, pure hydroxytyrosol, and a standard antibiotic as references. Analysis of knot characteristics showed variations in the virulence of the P.\u00a0savastanoi pv. savastanoi strains, with the highest virulence being observed for the strain I7L and the lowest virulence for the strain B45C-PR. The olive cultivar Rosinjola displayed higher susceptibility compared to Frantoio, Bu\u017ea, and Leccino, while cv. Istarska bjelica exhibited the least susceptibility compared to the other investigated olive cultivars. In an attempt to explore alternative solutions for disease control, in vitro tests revealed that the phenol HTyr, GE, and the wastewater with the highest total phenolic content (cv. Istarska bjelica) possess the highest antibacterial activity. This supports the role of polyphenols in host defense, aligning with previous field observations of lower susceptibility of cv. Istarska bjelica to olive knot disease. These findings highlight the complex nature of olive knot interactions with bacterial strains and olive cultivars, simultaneously accentuating and underscoring the importance of considering the host\u2019s defenses as well as bacterial virulence in disease management strategies.<\/jats:p>","DOI":"10.3390\/microorganisms12071301","type":"journal-article","created":{"date-parts":[[2024,6,26]],"date-time":"2024-06-26T07:20:06Z","timestamp":1719386406000},"page":"1301","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Varietal Susceptibility of Olive to Pseudomonas savastanoi pv. savastanoi and the Antibacterial Potential of Plant-Based Agents"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4737-8679","authenticated-orcid":false,"given":"Laura","family":"Ko\u0161\u0107ak","sequence":"first","affiliation":[{"name":"Department of Agriculture and Nutrition, Institute of Agriculture and Tourism, Carlo Hugues 8, 52440 Pore\u010d, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6358-4486","authenticated-orcid":false,"given":"Janja","family":"Lamov\u0161ek","sequence":"additional","affiliation":[{"name":"Agricultural Institute of Slovenia, Hacquetova ulica 17, 1000 Ljubljana, Slovenia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marina","family":"Luki\u0107","sequence":"additional","affiliation":[{"name":"Department of Agriculture and Nutrition, Institute of Agriculture and Tourism, Carlo Hugues 8, 52440 Pore\u010d, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2612-6918","authenticated-orcid":false,"given":"Tvrtko Karlo","family":"Kova\u010devi\u0107","sequence":"additional","affiliation":[{"name":"Department of Agriculture and Nutrition, Institute of Agriculture and Tourism, Carlo Hugues 8, 52440 Pore\u010d, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0786-9062","authenticated-orcid":false,"given":"Edyta","family":"\u0110ermi\u0107","sequence":"additional","affiliation":[{"name":"Department of Plant Pathology, Division of Phytomedicine, University of Zagreb Faculty of Agriculture, Sveto\u0161imunska Cesta 25, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0350-5074","authenticated-orcid":false,"given":"Smiljana","family":"Goreta Ban","sequence":"additional","affiliation":[{"name":"Department of Agriculture and Nutrition, Institute of Agriculture and Tourism, Carlo Hugues 8, 52440 Pore\u010d, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4922-3681","authenticated-orcid":false,"given":"Nikola","family":"Major","sequence":"additional","affiliation":[{"name":"Department of Agriculture and Nutrition, Institute of Agriculture and Tourism, Carlo Hugues 8, 52440 Pore\u010d, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1937-4611","authenticated-orcid":false,"given":"Sara","family":"Godena","sequence":"additional","affiliation":[{"name":"Department of Agriculture and Nutrition, Institute of Agriculture and Tourism, Carlo Hugues 8, 52440 Pore\u010d, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1016\/j.scitotenv.2016.10.032","article-title":"Potential application of olive mill wastewater as biopesticide for crops protection","volume":"576","author":"Saadaoui","year":"2017","journal-title":"Sci. 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