Amrisha Sreekissoon, Weiyang Chen, Alvaro M Viljoen, Jeffrey F Finnie, Johannes Van Staden
{"title":"The Effects of Light, Salt, and Osmotic Stress on Mesembryanthemum tortuosum Growth and Mesembrine-Type Alkaloid Production In Vitro.","authors":"Amrisha Sreekissoon, Weiyang Chen, Alvaro M Viljoen, Jeffrey F Finnie, Johannes Van Staden","doi":"10.1111/ppl.70385","DOIUrl":"https://doi.org/10.1111/ppl.70385","url":null,"abstract":"<p><p>Mesembryanthemum tortuosum is a valuable South African medicinal plant. A wide range of pharmacological and therapeutic actions have been ascribed to the plants' mesembrine-type alkaloids. Alkaloids are naturally produced in minute quantities in plants; however, production is often increased in stress conditions. This study aimed to determine the effects of abiotic stress on M. tortuosum growth and mesembrine-type alkaloid production. Light (0, 8, 16, and 24 h), salt (0, 50, 100, and 200 μM NaCl), and osmotic stress (0, 25, 50, and 100 g L<sup>-1</sup> polyethylene glycol; PEG) were applied to M. tortuosum cultures in vitro. Growth effects were recorded after 28 days. Alkaloid extracts were analyzed with UPLC-MS. Total mesembrine-type alkaloid contents were significantly increased by 0 h light and 100 g l<sup>-1</sup> PEG (9.16 ± 0.12 and 6.74 ± 0.30 μg mg<sup>-1</sup> DW, respectively), in comparison to the controls (2.93 ± 0.16 and 3.73 ± 0.014 μg mg<sup>-1</sup> DW, respectively). Zero h light allowed for more optimal plantlet growth than osmotic stress treatments. Growth effects and conservation of secondary metabolite pools in the presence of salt confirmed that M. tortuosum has a halophytic nature. Abiotic stress application is a simplistic and inexpensive method of enhancing mesembrine-type alkaloid production in M. tortuosum. With some modification, these methods could prove valuable to small- and large-scale growers of M. tortuosum, along with biotechnologists and pharmaceutical companies. The growing need for commercial availability of these phytochemicals could possibly be satiated with the appropriate use of the stress conditions described.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 4","pages":"e70385"},"PeriodicalIF":5.4,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144626960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rakesh Tiwari, Balachandra Hegde, Shrihari Hegde, Peddiraju Bandaru, M Ramesh Babu, K G Somashekhara Achar, Caroline Greiser, Robert Muscarella, Deepak Barua, David Galbraith, Emanuel Gloor
{"title":"Contrasting Seasonal Variation of Photosynthesis in Evergreen and Deciduous Tree Species From a Tropical Forest.","authors":"Rakesh Tiwari, Balachandra Hegde, Shrihari Hegde, Peddiraju Bandaru, M Ramesh Babu, K G Somashekhara Achar, Caroline Greiser, Robert Muscarella, Deepak Barua, David Galbraith, Emanuel Gloor","doi":"10.1111/ppl.70410","DOIUrl":"10.1111/ppl.70410","url":null,"abstract":"<p><p>Microclimate differences in water availability can drive seasonal water use and photosynthetic variation among co-occurring tropical tree species, especially in forests with strongly seasonal climates. We studied a tropical forest site in the Western Ghats, India, and characterised seasonal differences in photosynthetic CO<sub>2</sub> assimilation rates (A<sub>net</sub>) among nine tree species with contrasting leaf habit and topographic affinities: deciduous species in dry hilltops, dry-affinity evergreens on slopes and wet-affinity evergreens in valleys. Surface soil moisture was lowest in hilltops, intermediate on slopes and highest in valleys, with higher levels during the wet period compared to the dry period. As expected, deciduous species on dry hilltops showed higher photosynthetic rates at the thermal optimum (T<sub>opt</sub>) during the wet period, while evergreen species showed no overall seasonal differences. Interestingly, evergreen species with a dry affinity on hill slopes showed higher A<sub>net</sub> at the thermal optimum during the dry period compared to the wet period, despite lower soil moisture. This suggests that these species either have sufficient water availability during the dry period or possess a warmer thermal niche preference/adaptation. Across species, stomatal conductance (g<sub>s</sub>) at T<sub>opt</sub> was generally higher during the wet period, except for one evergreen species. Our findings illustrate seasonal differences in photosynthesis among tropical tree species across different leaf habits and topographic affinities.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 4","pages":"e70410"},"PeriodicalIF":5.4,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12257110/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144626956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zahid Ahmed Mangral, Shahid Ul Islam, Aasim Majeed, Lubna Tariq, Shailendra Goel, Saroj K Barik, Tanvir Ul Hassan Dar
{"title":"Transcriptomic Insights Into Elevation-Dependent Gene Expression in Rhododendron anthopogon D.Don: Implications for Climate Resilience.","authors":"Zahid Ahmed Mangral, Shahid Ul Islam, Aasim Majeed, Lubna Tariq, Shailendra Goel, Saroj K Barik, Tanvir Ul Hassan Dar","doi":"10.1111/ppl.70419","DOIUrl":"https://doi.org/10.1111/ppl.70419","url":null,"abstract":"<p><p>Understanding the molecular basis of how species adapt to varying elevations can advance our knowledge regarding forecasting and regulating the consequences of climate change on plants. Here, we investigate the variation in gene expression patterns of Rhododendron anthopogon D.Don along an elevation gradient (3200-3900 m) in Kashmir Himalaya, India, based on comparative transcriptomics. We observe the highest number of differentially expressed transcripts between the lowest (3200 m) and highest (3900 m) sites, indicating a strong elevation-associated divergence in gene activities. Most of these transcripts were significantly enriched in biological processes linked to stress response and secondary metabolism, suggesting their role in the elevation-dependent adaptation of R. anthopogon. We identified different genes for secondary metabolite production; the expression pattern of these genes increased with the rise in altitude. By using gene co-expression network (GCN) analysis to elucidate the interaction between targeted genes and regulators, we found that 200 transcription factors belonging to 36 families were putatively involved in regulating important metabolic pathways of R. anthopogon in response to changing altitudes. Thus, these metabolic pathways may play an important role in the adaptation of R. anthopogon in response to environmental stress along an elevation gradient. Therefore, the findings of this study will provide insights into how alpine R. anthopogon adapts to environmental responses to global climate change.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 4","pages":"e70419"},"PeriodicalIF":5.4,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144691228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zalán Czékus, András Kukri, Atina Martics, Boglárka Pollák, Árpád Molnár, Attila Ördög, Györgyi Váradi, László Galgóczy, Rebeka Papp, Liliána Tóth, Katalin Ágnes Kocsis, Nóra Faragó, Nikolett Bódi, Mária Bagyánszki, Gabriella Szalai, Kamirán Áron Hamow, Péter Poór
{"title":"Do guard cells have single or multiple defense mechanisms in response to flg22?","authors":"Zalán Czékus, András Kukri, Atina Martics, Boglárka Pollák, Árpád Molnár, Attila Ördög, Györgyi Váradi, László Galgóczy, Rebeka Papp, Liliána Tóth, Katalin Ágnes Kocsis, Nóra Faragó, Nikolett Bódi, Mária Bagyánszki, Gabriella Szalai, Kamirán Áron Hamow, Péter Poór","doi":"10.1111/ppl.70249","DOIUrl":"https://doi.org/10.1111/ppl.70249","url":null,"abstract":"<p><p>Bacterial flagellin (flg22) induces rapid and permanent stomatal closure. However, its local and systemic as well as tissue- and cell-specific effects are less understood. Our results show that flg22 induced local and systemic stomatal closure in intact tomato plants, which was regulated by reactive oxygen- and nitrogen species, and also affected the photosynthetic activity of guard cells but not of mesophyll cells. Interestingly, rapid and extensive local expression of Ethylene response factor 1 was observed after exposure to flg22, whereas the relative transcript levels of Defensin increased only after six hours, especially in systemic leaves. Following local and systemic ethylene emission already after one and six hours, jasmonic acid levels increased in the local leaves after six hours of flg22 treatment. Using immunohistochemical methods, significant defensin accumulation was found in the epidermis and stomata of flg22-treated leaves and above them. Immunogold labelling revealed significant levels of defensins in the cell wall of the mesophyll parenchyma and guard cells. Furthermore, single cell qRT-PCR confirmed that guard cells are able to synthesise defensins. It can be concluded that guard cells are not only involved in the first line of plant defense by regulating stomatal pore size, but can also defend themselves and the plant by producing and accumulating antimicrobial defensins where phytopathogens can penetrate.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70249"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12067365/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144015673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vinícius Fernandes de Souza, Michelle Robin, Bahtijor Rasulov, Eero Talts, Eliane Gomes Alves, Bader O Almutairi, Ülo Niinemets
{"title":"High temperature acclimation of isoprene emission in date palm is associated with enhanced substrate availability and reduction in synthase activity.","authors":"Vinícius Fernandes de Souza, Michelle Robin, Bahtijor Rasulov, Eero Talts, Eliane Gomes Alves, Bader O Almutairi, Ülo Niinemets","doi":"10.1111/ppl.70256","DOIUrl":"https://doi.org/10.1111/ppl.70256","url":null,"abstract":"<p><p>Heatwaves enhance plant isoprene emissions, but the relative contributions of instantaneous temperature effects on rate-limiting enzymes and longer-term acclimation remain unclear. We explored the controls on isoprene emission by isoprene synthase (IspS) activity and MEP pathway intermediates, dimethylallyl diphosphate (DMADP) and 2-C-methyl-D-erythritol 2,4-cyclodiphosphate (MEcDP) pool size in Phoenix dactylifera cv. Medjool subjected to a temperature transient: stabilization at 25°C (Phase 1), an increase to 37°C (Phase II), and return to 25°C (Phase III). The rapid temperature rise increased isoprene emission due to immediate effects on IspS activity, followed by sustained increases driven by expanded DMADP and MEcDP pools. Upon cooling (Phase III), isoprene emissions dropped below initial levels due to reduced IspS activity, but recovered as substrate pool sizes increased. Acclimation to elevated temperature was driven by increased DMADP availability, which persisted after cooling, while slower MEcDP acclimation maintained carbon flux toward DMADP. The data indicate that the sustained moderate heat stress inhibits IspS, but increases substrate availability for isoprene synthesis. Thus, beyond the immediate IspS response, longer-term rises in isoprene emissions result from reprogrammed DMADP-consuming reactions, enhancing substrate availability. These findings provide new insight into the regulation of isoprene under thermal stress and underscore the need to integrate both intermediate pool dynamics and IspS activity into predictive models of isoprene emission and deepen our understanding of the MEP pathway's role under fluctuating environmental conditions.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70256"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144027109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Soheila Aghaei Dargiri, Shahram Naeimi, Ali Movahedi
{"title":"Exiguobacterium aurantiacum SA100 induces antioxidant enzymes and salinity tolerance gene expression in wheat.","authors":"Soheila Aghaei Dargiri, Shahram Naeimi, Ali Movahedi","doi":"10.1111/ppl.70258","DOIUrl":"https://doi.org/10.1111/ppl.70258","url":null,"abstract":"<p><p>This study evaluated the effects of Exiguobacterium aurantiacum SA100 on wheat (Triticum aestivum) growth under varying levels of salinity stress. Results indicated that SA100 significantly enhanced seed germination, root and shoot length, and fresh and dry biomass across salinity levels, particularly at 50 and 100 mM NaCl. Inoculation improved antioxidant enzyme activities (CAT, APX, POD, PPO), increased total phenolic content, and reduced oxidative damage by lowering MDA and H<sub>2</sub>O<sub>2</sub> levels under 150 mM salinity. Ionic balance was maintained, with significant increases in K<sup>+</sup>, Mg<sup>++</sup>, and Ca<sup>++</sup> and a reduction in Na<sup>+</sup> accumulation. Gene expression analysis revealed upregulation of salt-tolerance genes (NAC7, NHX1, SOS1) and downregulation of stress-responsive genes (GS1, DREB2, DHN13, WRKY32). Principal component analysis confirmed that SA100 promotes salinity tolerance by modulating both biochemical and molecular responses. These findings suggest E. aurantiacum SA100 as a promising bioinoculant for enhancing wheat resilience under salinity stress.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70258"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144040001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yong Cui, Yongju Zhao, Liangliang Li, Shengnan Ouyang, Mingkai Jiang, David T Tissue, Honglang Duan
{"title":"Acclimation to Warming Shapes Gas Exchange and Metabolic Responses to Heat Shock in Pinus massoniana Seedlings.","authors":"Yong Cui, Yongju Zhao, Liangliang Li, Shengnan Ouyang, Mingkai Jiang, David T Tissue, Honglang Duan","doi":"10.1111/ppl.70265","DOIUrl":"https://doi.org/10.1111/ppl.70265","url":null,"abstract":"<p><p>The sensitivity of physiological and metabolic processes in subtropical trees to temperature remains uncertain, limiting our ability to predict how subtropical forests will acclimate to future climates. In particular, our understanding of gas exchange and metabolic activity responses to warming and heat shocks is quite limited. Here, we exposed Pinus massoniana seedlings to three daytime growth temperatures (25°C, 3°C, and 35°C) for 65 days, followed by a heat shock up to 40°C, then immediately reduced to 25°C, to investigate physiological and metabolic responses. The optimal temperature of photosynthesis (T<sub>optA</sub>) did not exhibit a significant shift with warming. Metabolism acclimated to rising growth temperature, resulting in enriched levels of key metabolites (tryptophan, indole, indoleacetate, and o-Phospho-L-serine) and key pathways (tryptophan metabolism). At 25°C, leaf dark respiration (R<sub>d</sub>) decreased in warm-grown seedlings. At 40°C (heat shock period), warming reduced R<sub>d</sub>, accumulated flavonoid metabolites, and upregulated tryptophan metabolism. After recovery to 25°C, higher growth temperatures decreased the net photosynthetic rate (A<sub>sat</sub>), accumulated prenol lipid metabolites, and led to enrichment in tryptophan metabolism, flavone, and flavonol biosynthesis pathways. Our findings suggest that photosynthesis in P. massoniana seedlings exhibits limited thermal acclimation, while respiration and metabolism can acclimate under short-term warming. However, acclimation to warming altered both physiological and metabolic responses to heat shock and during the subsequent recovery phase in seedlings.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70265"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144120576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shixiong Lu, Lili Che, Huimin Gou, Min Li, Baozhen Zeng, Juanbo Yang, Baihong Chen, Juan Mao
{"title":"Integrated Transcriptomic and Proteomic Analyses Demonstrated That MeJA-Regulated VvPAL10 Enhances Cold Tolerance in Grapevines.","authors":"Shixiong Lu, Lili Che, Huimin Gou, Min Li, Baozhen Zeng, Juanbo Yang, Baihong Chen, Juan Mao","doi":"10.1111/ppl.70299","DOIUrl":"https://doi.org/10.1111/ppl.70299","url":null,"abstract":"<p><p>Understanding the molecular mechanisms underlying cold and methyl jasmonate (MeJA) responses is vital for improving the cold tolerance of grapes. This study treated 'Pinot noir' plantlets with MeJA, screened key genes in the regulatory pathway using transcriptomics and proteomics analyses, and investigated their regulatory mechanisms under cold stress. The results showed that 50 μmol L<sup>-1</sup> MeJA significantly inhibited the growth of grape roots length, increased the endogenous MeJA content and antioxidant enzyme activities, and reduced membrane damage under cold stress. In addition, 50 μmol L<sup>-1</sup> MeJA and cold stress treatment greatly increased the number of differential genes and metabolites in the phenylalanine synthesis and hormone signal transduction pathways. The results indicated that VvPAL10, an important gene in the phenylalanine synthesis pathway, significantly improved transgenic Arabidopsis thaliana and grapevine callus tissue tolerance to low temperatures.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70299"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144209165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Review of the Chemical Composition and Biological Activities of Sugarcane: Potential Medicinal Value and Sustainable Development.","authors":"Dongdong Wang, Jiatong Zheng, Surendra Sarsaiya, Jisen Zhang","doi":"10.1111/ppl.70293","DOIUrl":"https://doi.org/10.1111/ppl.70293","url":null,"abstract":"<p><p>Sugarcane (Saccharum spp.) is an important cash crop widely grown in tropical and subtropical regions. In addition to being the main raw material for sugar and ethanol production, it is rich in a wide range of bioactive compounds with remarkable chemical diversity and biological activity. In recent years, sugarcane research has gradually increased due to the increased interest in natural medicines and functional foods. This paper reviews the chemical constituents and their potential bioactivities of sugarcane. These include flavonoids, flavonoid carbonyl glycosides, flavonols, dihydroflavonoids, dihydroflavonols, chalcones and flavanols. China's traditional Chinese medicine resources are facing serious problems in terms of sustainable development, causing a shortage aggravated by changes in the natural environment and species composition as well as uncontrolled human harvesting. Therefore, it is of great significance for the maintenance and development of traditional Chinese medicine resources to study such resources, which have medicinal value and crop potential, and discover new uses for them. In this review, we discuss the chemical composition of sugarcane and its potential bioactivities, explore its applications in the field of medicine and look for the direction of future research.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70293"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144161047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anna Fiorillo, Michela Manai, Mauro Marra, Lorenzo Camoni
{"title":"A Biostimulant Based on Ecklonia maxima and Yeast Extract Increases the Resistance of Tomato Plants Toward Pseudomonas syringae pv. tomato DC3000.","authors":"Anna Fiorillo, Michela Manai, Mauro Marra, Lorenzo Camoni","doi":"10.1111/ppl.70301","DOIUrl":"https://doi.org/10.1111/ppl.70301","url":null,"abstract":"<p><p>Plant biostimulants represent a promising option to improve agricultural production and stress resistance while reducing the use of fertilizers and pesticides. Despite various evidence demonstrating the beneficial role of biostimulants in preventing the negative effects of abiotic stress on plants, the ability of biostimulants to bolster defense mechanisms has been brought to light only recently. In this work, the impact of a biostimulant based on Ecklonia maxima and yeast extracts (S/Y) on the response of tomato infected with Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) was assessed. S/Y was selected after a screening to identify biostimulants capable of conferring resistance to Pst DC3000. S/Y boosts the early events of the plant's innate immunity. Indeed, biostimulation increased the Pst DC3000-induced oxidative burst by upregulating the NADPH oxidase/respiratory burst oxidase homolog and apoplastic class III peroxidases expression. Moreover, the deposition of callose was also promoted. Due to improved activation of early defense responses by S/Y, disease symptoms and bacterial spread 72 h after the infection were significantly reduced. Finally, levels of salicylic acid, a key hormone in plant innate immunity, were increased by S/Y, whilst those of jasmonic acid and auxin, which are negative regulators in defense responses to Pst DC3000, were hampered. Overall, these findings show that S/Y mitigates infection symptoms by acting on different defense mechanisms, thus providing evidence of the potential of the biostimulant to improve plants' response to biotic stresses.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70301"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144180888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}