Epiphytic bacteria from Tacinga inamoena (K. Schum.) N.P. Taylor & Stuppy improve plant growth in cucumber seedlings - PMC Skip to main content An official website of the United States government Here's how you know Here's how you know Official websites use .gov A .gov website belongs to an official government organization in the United States. Secure .gov websites use HTTPS A lock ( Lock Locked padlock icon ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites. Search Log in Dashboard Publications Account settings Log out Search… Search NCBI Primary site navigation Search Logged in as: Dashboard Publications Account settings Log in Search PMC Full-Text Archive Search in PMC Journal List User Guide PERMALINK Copy As a library, NLM provides access to scientific literature. Inclusion in an NLM database does not imply endorsement of, or agreement with, the contents by NLM or the National Institutes of Health. 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Taylor & Stuppy improve plant growth in cucumber seedlings Ellie José Pereira Ellie José Pereira 1 Department of Education, State University of Bahia, Paulo Afonso, Brazil Find articles by Ellie José Pereira 1, ✉ , Vinícius de Souza Vinícius de Souza 1 Department of Education, State University of Bahia, Paulo Afonso, Brazil Find articles by Vinícius de Souza 1 , Caliane da Silva Braulio Caliane da Silva Braulio 1 Department of Education, State University of Bahia, Paulo Afonso, Brazil Find articles by Caliane da Silva Braulio 1 , Adailson Feitoza de Jesus Santos Adailson Feitoza de Jesus Santos 1 Department of Education, State University of Bahia, Paulo Afonso, Brazil Find articles by Adailson Feitoza de Jesus Santos 1 Author information Article notes Copyright and License information 1 Department of Education, State University of Bahia, Paulo Afonso, Brazil ✉ Corresponding author. Received 2025 Oct 24; Revised 2025 Dec 25; Accepted 2026 Jan 14; Issue date 2026. © The Author(s) 2026 Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/ . PMC Copyright notice PMCID: PMC13083309 PMID: 41774319 Abstract The phyllosphere of host plants harbors microorganisms that represent a novel source of agricultural bioinputs. This unique microbiome opens a promising frontier for developing innovative agricultural alternatives. In this study, we evaluated the potential of Brevibacillus sp. UPT4 and Pantoea sp. SPM1, two epiphytic bacterial strains of Tacinga inamoena isolated from the Caatinga biome. In vitro assays exhibited plant growth-promoting traits, such as auxin production, nitrogen fixation, and tolerance to abiotic stresses. Under greenhouse conditions, cucumber plants inoculated with the strains and their consortium exhibited significant increases ( p < 0.05) in shoot and root parameters, ranging from 13.58% to 194.86% when compared to the control treatment. Redundancy analysis (RDA) indicated that most of the variability observed in the biometric parameters is associated with the plant growth-promoting reported in this study. These results highlight the potential of epiphytic bacteria from semi-arid land as a promising candidate for the development of new bioinputs, offering an innovative tool for sustainable agriculture. Keywords: Agriculture, Bioinputs, Caatinga, Cucumber, Phyllosphere Introduction The rapid growth of the global population poses significant challenges to food security, with projections estimating approximately 10 billion inhabitants by 2050. It is anticipated that population expansion, combined with changes in consumption patterns and increased per capita income, will raise global food demand by around 44% (OECD-FAO 2024 ; Sands et al. 2023 ). Concurrently, economic and territorial conflicts, together with the escalating climate crisis, exacerbate global food insecurity (Safi et al. 2024 ; Marson and Sacconel 2023 ). In Brazil, vegetable production plays a strategic role in food security. Within this context, cucumber ( Cucumis sativus L.) stands out due to its high domestic demand and market acceptance. However, the pursuit of high yields has favored the intensive use of chemical pesticides and mineral fertilizers to ensure crop productivity, a practice that can compromise soil and water quality, in addition to altering the structure and functionality of the microbial communities associated with plants (Mallick 2022 ; Kaur and Sharma 2021 ). In this scenario, biofertilizers based on plant growth-promoting bacteria (PGPB) has emerged as a promising tool for sustainable agriculture. PGPB constitute a functionally diverse group of microorganisms, including bacteria from the genera Bacillus , Pseudomonas , Azospirillum , Rhizobium , and Bradyrhizobium , which are widely distributed in natural and agricultural environments (Barbosa et al. 2025 ). This taxonomic diversity is associated with a range of strategies that enable plant growth-promotion through multiple mechanisms, including phytohormone production, biological nitrogen fixation (BNF), and nutrient solubilization, thereby supporting crop development (Srivastava and Joshih 2021 ; Bahloul 2021 ; Shahwar et al. 2023 ; Alzate Zuluaga et al. 2024 ). The prospecting for novel PGPB has expanded to natural environments that are still underexplored, where microbial diversity may represent an important source of microorganisms with high biotechnological potential. Native plants, especially those adapted to specific environmental conditions, such as in semi-arid regions, act as reservoirs of functionally specialized microbial communities. In this context, the phyllosphere constitutes a highly dynamic ecological niche, characterized by intense microbial selection, in which bacteria develop efficient colonization, survival, and interaction strategies with the plant host, as seen in cactus species (Liu et al. 2023 ; Flores-Nuñez et al. 2025 ). Recent studies demonstrate that microorganisms isolated from the phyllosphere of native plants exhibit a high capacity to promote the growth of agricultural crops, expanding the possibilities for the development of innovative bioestimulants (Devarajan et al. 2021 ; Sharath et al. 2021 ; Agbodiato and Babalola 2024 ; Khosravi et al. 2024 ). The isolation and characterization of new epiphytic strains can directly contribute to the development of efficient bioinputs and foster sustainable agricultural practices. In this context, this study aimed to evaluate the effects of Brevibacillus sp. UPT4 and Pantoea sp. SPM1, two novel strains isolated from the phyllosphere of Tacinga inamoena (K. Schum.) N.P. Taylor & Stuppy, on cucumber seedlings growth. Materials and methods Microorganisms Brevibacillus sp. UPT4 and Pantoea sp. SPM1 were isolated from the surface of T. inamoena cladodes. Brevibacillus sp. UPT4 was isolated in Serra do Umbuzeiro (Latitude: − 9.58103091088262; Longitude: − 38.2047843933105), Paulo Afonso, Bahia state, Brazil. Pantoea sp. SPM1 was isolated in Environmental Protection Area Serra Branca (Latitude: − 9.945193254158575; Longitude: − 38.57322551035467), located in the municipality of Jeremoabo, Bahia state, Brazil. Swabs moistened in a NaCl 0.85% and Tween 80 0.3% solution were rubbed on the surface of plant cladodes and placed in tubes containing a 0.85% NaCl solution (Pereira da Silva et al. 2025 ). The aliquots were inoculated into Trypticasein Soy Agar (TSA) medium (Kasvi ® ), and morphologically distinct colonies were purified, cryopreserved at −80 °C and deposited into the microbial collection of the Laboratory of Microbial Ecology and Biotechnology of the Semi-Arid Region (LEBIMS–UNEB). The strains were selected for this study based on their potential previously identified in assays conducted at LEBIMS (unpublished data). Evaluation of plant growth-promoting potential and tolerance to abiotic stresses Indole-3-acetic acid (IAA) production Bacterial cultures (OD 600nm = 0.3) were inoculated into Trypticasein Soy Broth (TSB) (Kasvi ® ) supplemented with L-tryptophan (5 mM) and incubated under constant agitation (150 rpm) at 28 ± 2 °C for 72 h. Bacterial cultures (OD 600nm = 0.3) were inoculated into Trypticasein Soy Broth (TSB) (Kasvi ® ) supplemented with L-tryptophan (5 mM) and incubated under constant agitation (150 rpm) at 28 ± 2 °C for 72 h. Cultures were centrifuged at 10,000 rpm for 10 min, and the cell-free supernatant was transferred to tubes containing Salkowski reagent (2% FeCl₃ in 35% HClO₄) (1:1), following Gordon and Weber ( 1951 ). The mixture was incubated in the dark for 30 min, and IAA concentration was determined spectrophotometrically at 530 nm (UV-5100, Metash), using a standard curve of IAA. Asymbiotic nitrogen fixation Bacterial cultures (OD 600nm = 0.3) were inoculated into tubes containing semi-solid nitrogen-free Burk’s medium (Wilson and Knight 1952 ) with the following composition (g L⁻¹): glucose (10), agar (1.8), K₂HPO₄ (0.52), KH₂PO₄ (0.41), CaCl₂ (0.2), MgSO₄·7 H₂O (0.1), Na₂SO₄ (0.05), FeSO₄·7 H₂O (0.005), and Na₂MoO₄·2 H₂O (0.0025), pH adjusted to 7.0. Tubes were incubated at 28 ± 2 °C for 7 days, and the formation of a sub-surface pellicle indicated asymbiotic nitrogen fixation capacity. Phosphorus (P) and potassium (K) solubilization Bacterial colonies were streaked onto Pikovskaya’s agar (TM Media ® ) and Aleksandrow agar (TM Media ® ) plates for the determination of phosphorus and potassium solubilization capacity, respectively. Plates were incubated at 28 ± 2 °C for 15 days, and solubilization activity was evidenced by halo formation around the bacterial colonies (Pikovskaya 1948 ; Aleksandrov et al. 1967 ). Growth under reduced water activity (A w ) Strains were streaked onto tryptic soy agar (TSA) supplemented with different concentrations of sorbitol (285, 405, 520, and 780 g L⁻¹), corresponding to water activity (A w ) values of 0.957, 0.919, 0.897, and 0.807, respectively (Hallworth et al. 1998 ). Plates were incubated at 28 ± 2 °C for 48 h, and tolerance to water stress was determined based on bacterial growth at each A w level. Salt tolerance Strains were streaked onto TSA medium supplemented with NaCl at concentrations of 0, 2, 4, 6, 8, and 10%. Plates were incubated at 28 ± 2 °C for 48 h, and salt tolerance was evaluated based on bacterial growth at each concentration. Evaluation of plant growth promotion in cucumber Experimental design The experiment was conducted for 25 days in a greenhouse covered with polyethylene film and sidewalls protected with 30% shade cloth, under natural photoperiod, with average temperatures of 36 ± 2 °C (day) and 24 ± 2 °C (night), at the State University of Bahia (UNEB), Campus VIII, Paulo Afonso, Bahia, Brazil, in December 2024.The experiment was conducted for 25 days in a greenhouse covered with polyethylene film and sidewalls protected with 30% shade cloth, under natural photoperiod, with average temperatures of 36 ± 2 °C (day) and 24 ± 2 °C (night), at the State University of Bahia (UNEB), Campus VIII, Paulo Afonso, Bahia, Brazil, in December 2024. Cucumber seeds were surface-sterilized with 70% ethanol (1 min), 1% NaOCl (3 min), and rinsed three times with sterile distilled water. Seeds were then microbiolized by immersion in bacterial inoculum adjusted to OD 600nm = 1.0 with xanthan gum (0.1%) as an adhesive agent. The control treatment consisted of seeds immersed only in 0.1% xanthan gum solution. The experimental design was a completely randomized block design with four treatments and five replicates, totaling 20 experimental units. Treatments included: (T1) uninoculated control, (T2) co-inoculation of Pantoea sp. SPM1 and Brevibacillus sp. UPT4, (T3) inoculation with Pantoea sp. SPM1, and (T4) inoculation with Brevibacillus sp. UPT4. Seeds were sown in pots containing 2 kg of soil with the following chemical characteristics: pH 7.91; 89.5 mg dm − ³ P (Mehlich-1); 0.64 cmolc dm − ³ K+; 9.99 cmolc dm − ³ calcium (Ca 2+ ); and electrical conductivity of 1.00 dS m − 1 . Plants were irrigated daily to maintain adequate soil water content, which was monitored by daily weighing of the pots in the late afternoon, considering both plant fresh mass and soil mass. Evaluations were performed 25 days after emergence (DAE). Shoots were cut at the cotyledonary node, separating roots and shoots. Stem diameter was measured in millimeters using a digital caliper. Shoot length (SL) and root length (RL) were measured with a graduated ruler. Root volume (RV) was determined by water displacement in a graduated cylinder. Shoots and roots were placed in paper bags and oven-dried at 60 ± 2 °C until constant weight, which was used to determine shoot biomass allocation (SBA) and root biomass allocation (RBA) (Poorter et al. 2012 ). Statistical analysis Data were subjected to analysis of variance (ANOVA) using the F-test ( p < 0.05). When significant differences were detected, means were compared using the Scott-Knott test at the 5% probability level. Relationships between in vitro assay parameters and cucumber growth experiment variables were assessed by Redundancy Analysis (RDA) based on Pearson’s correlation matrix. Statistical analyses were performed in RStudio software (v. 4.3.3) (R Core Team 2024 ). Results Functional profile of Brevibacillus sp. UPT4 and Pantoea sp. SPM1 indicates potential for plant growth promotion and tolerance to abiotic stresses Both strains exhibited multiple traits associated with plant growth promotion and tolerance to abiotic stresses (Table 1 ). Brevibacillus sp. UPT4 and Pantoea sp. SPM1 demonstrated the ability to produce indole-3-acetic acid (IAA), with concentrations of 58.93 and 53.19 µg/mL, respectively. Similarly, both strains displayed the capacity for asymbiotic nitrogen fixation. Table 1. Functional traits associated with plant growth promotion and tolerance to abiotic stresses exhibited by Brevibacillus sp. UPT4 and Pantoea sp. SPM1 STRAIN IAA ANF K P Aw NaCl Pantoea sp. SPM1 53.19 + + - 0.957 8% Brevibacillus sp. UPT4 58.93 + - - 0.957 4% Open in a new tab IAA = Indole-3-acetic acid production (µg/mL); ANF = Asymbiotic nitrogen fixation; K = Potassium solubilization; P = Phosphorus solubilization; Aw = Growth under reduced water activity; NaCl = Salinity tolerance Regarding the solubilization of mineral nutrients, only Pantoea sp. SPM1 exhibited potassium-solubilizing ability, whereas neither strain demonstrated phosphorus-solubilizing capacity. With respect to growth under abiotic stress conditions, both strains were able to grow under low water availability as well as under saline stress. Pantoea sp. SPM1 sustained growth at NaCl concentrations of up to 8%, while Brevibacillus sp. UPT4 tolerated up to 4% NaCl. Epiphytic strains from T. inamoena modulate growth, root architecture, and biomass allocation in cucumber seedlings The experiment demonstrated a significant effect ( p < 0.05) of strain inoculation on cucumber growth. For shoot length (SL), distinct responses were observed among the treatments (Fig. 1 a), with the bacterial consortium (Fig. 1 b) and Brevibacillus sp. UPT4 (Fig. 1 c) standing out, promoting increases of 38.52% and 56.59%, respectively, compared to the control treatment (Fig. 2 a). Similarly, for stem diameter (SD), co-inoculation and inoculation with Brevibacillus sp. UPT4 resulted in values 13.58% and 20.20% higher, respectively, than the uninoculated treatment (Fig. 2 b). Inoculation with Pantoea sp. SPM1 (T3) did not differ statistically from the control. Fig. 1. Open in a new tab Cucumber seedlings inoculated with epiphytic bacterial isolated from the Caatinga biome. ( a ) Comparison between treatments. ( b ) Cucumber inoculated with bacterial consortium, and ( c ) cucumber inoculated with Brevibacillus sp. UPT4. The scale bar in blue corresponds to panel ( a ); the scale bars in yellow correspond to panels ( b ) and ( c ) Fig. 2. Open in a new tab Effect of epiphytic bacterial from T. inamoena on ( a ) shoot length (SL) and ( b ) stem diameter (SD) For root length (RL), all inoculated treatments showed higher means than the control; however, only Brevibacillus sp. UPT4 exhibited a significant increase of 43.40% (Fig. 3 a). All inoculated treatments increased the root volume (RV) of cucumber seedlings compared to the control, with increments ranging from 92.86% to 117.86% (Fig. 3 b). Fig. 3. Open in a new tab Influence of inoculated treatments on ( a ) root length (RL) and ( b ) root volume (RV) of cucumber seedlings For shoot biomass allocation (SBA), all inoculated treatments showed lower mean values compared to the control (Fig. 4 a). Conversely, inoculation resulted in a higher percentage of biomass allocation to the roots (RBA) compared to the control (Fig. 4 b). Pantoea sp. SPM1 exhibited the greatest increase (194.86%), followed by the microbial consortium (141.94%) and Brevibacillus sp. UPT4 (110.69%). Fig. 4. Open in a new tab Biomass allocation in cucumber seedlings inoculated with epiphytic bacteria from T. inamoena : percentage of ( a ) shoot biomass allocation (SBA) and ( b ) root biomass allocation (RBA) Redundancy analysis (RDA) enabled the correlation of the functional profile of the strains with the evaluated phytometric parameters, explaining 83.3% and 16.7% of the variance along the first (RDA1) and second (RDA2) axes, respectively (Fig. 5 ). The results revealed that the greatest variability in RV, SD, RL, and SL was associated with the ability of the strains to produce indole-3-acetic acid (IAA). Moreover, asymbiotic nitrogen fixation capacity exhibited a positive correlation with root biomass allocation values, whereas SBA displayed distinct distribution patterns compared to the other parameters. Fig. 5. Open in a new tab Redundancy Analysis (RDA) showing the correlation between the observed functional traits and the results obtained in the cucumber experiment, including indole-3-acetic acid production (IAA), asymbiotic nitrogen fixation (ANF), potassium solubilization (K), phosphorus solubilization (P), growth under reduced water activity (Aw), salinity tolerance (NaCl), shoot length (SL), stem diameter (SD), root length (RL), root volume (RV), aboveground biomass allocation (ABA), and root biomass allocation (RBA). Notes: IAA = Indole-3-acetic acid production; ANF = Asymbiotic nitrogen fixation; K = Potassium solubilization; P = Phosphorus solubilization; Aw = Growth under reduced water activity; NaCl = Salinity tolerance; SL = Shoot length; SD = Stem diameter; RL = Root length; RV = Root volume; ABA = Aboveground biomass allocation; RBA = Root biomass allocation Discussion Arid and semi-arid regions are often characterized by stress conditions such as high temperatures, low relative air humidity, and reduced water availability. These factors modulate plant microbiome interactions, favoring the presence of microorganisms capable of assisting in nutrient uptake and stress responses, thereby promoting plant development (Yang et al. 2025 ). Phyllosphere microorganisms are exposed to extreme climatic fluctuations, which compel them to develop biochemical and physiological strategies that ensure their adaptability to hostile conditions. The formulation of inoculants based on microorganisms from the phyllosphere of semi-arid regions represents a promising biotechnological tool. Studies have shown that the genetic repertoire of epiphytic bacteria from cacti in such regions includes various mechanisms associated with phytohormone synthesis, nitrogen fixation, and stress tolerance. Similarly, Liu et al. ( 2023 ) emphasizes that epiphytic bacteria from desert plants possess specialized functional capabilities, serving as sources of metabolites and mechanisms applicable to agriculture. A specialized functional profile was identified in the present study, as both strains exhibited tolerance to abiotic stresses, including high salinity and low water activity. These findings are consistent with reports of phyllosphere microorganisms adapted to harsh environments, such as those associated with Tillandsia landbeckii Phil. in the Atacama Desert (Hakobyan et al. 2023 ) and phytobacteria associated with rice cultivars (Devarajan et al. 2021 ). The results of this study indicate that strains isolated from T. inamoena possess potential for agricultural application, particularly in cropping systems subjected to environmental stresses. The high IAA production observed suggests that the strains have potential for plant growth promotion (Table 1 ). The adverse conditions of the semi-arid climate exert selective pressure on the phyllosphere microbiota, triggering osmotic stress and inducing the expression of genes related to IAA production (Etesami and Glick 2024 ). As a result, tryptophan present in foliar exudates is assimilated by epiphytic communities, which secrete the phytohormone and stimulate plant development (Saleem and Paul 2015 ), as verified in this study. Mechanisms associated with mineral nutrient availability were also identified. Potassium solubilization, observed in Pantoea sp. SPM1, represents an important trait in plant growth promotion, enhancing photosynthesis and activating key enzymes (Pandey and Saharan 2025 ). In addition, the asymbiotic nitrogen fixation observed in both strains may integrate into the set of nutritional mechanisms available to cropping systems. The assimilation of atmospheric nitrogen in the phyllosphere, as reported for Methylobacterium symbioticum , may serve as an alternative in environments with low nutrient availability, while also reducing the need for chemical fertilizers (Valente et al. 2024 ). Although neither strain exhibited phosphorus solubilization capacity, this result did not compromise the plant growth gains observed. On the contrary, it suggests that other mechanisms, such as IAA production and nitrogen fixation, were more decisive, as observed on RDA. This finding reinforces that the potential of PGPB is not necessarily linked to the presence of all classical mechanisms, but rather to the functional effectiveness of those most relevant under specific environmental and physiological conditions. In this context, it is essential to consider the identification and selection of elite microorganisms, i.e., strains that, even with a limited set of traits, display high agronomic efficiency and functional plasticity across different cropping systems. In cucumber assays, significant increases in shoot growth were observed in treatments inoculated with the microbial consortium and with Brevibacillus sp. UPT4, particularly in SL and SD. These results suggest a possible synergistic action between IAA production and nitrogen fixation, promoting greater structural development and biomass allocation. Similar findings were reported in tomato and pepper seedlings inoculated with Brevibacillus brevis FJAT-0809-GLX, which showed significant increases in growth parameters after 14 days of cultivation (Che et al. 2018 ). The root system showed superior development in inoculated plants compared to the control. Increases in root architecture are strongly associated with IAA synthesis, which directly influences root growth. A more robust root system enhances water and nutrient uptake, thereby increasing crop resilience under conditions of water and nutrient limitation (Dias et al. 2023 ). In studies with maize (Maulina et al. 2022 ) and cotton (Nehra et al. 2016 ), inoculation with Brevibacillus spp. also resulted in significant gains in root length and biomass, reinforcing the ecological and functional plasticity of these microorganisms, even when originating from the phyllosphere. The effects observed with the microbial consortium may indicate advantages over single-strain formulations, as the combination of different microorganisms can broaden the spectrum of benefits to crops (). Studies with common bean (Verma et al. 2018 ), millet (Kushwaha et al. 2020 ), and pearl millet (Kaur et al. 2022 ) have shown that microbial consortia improve growth, biomass, and chlorophyll content. The present study also revealed differences in shoot and root biomass allocation. Inoculated plants displayed greater root biomass allocation compared to the control, consistent with findings by Awasthi et al. ( 2024 ) in Bacopa monnieri (L.) Wettst inoculated with Pantoea sp. MTP17. In this study, the higher root allocation rate observed with Pantoea sp. SPM1 may be related to its high IAA production and potassium solubilization, traits that favor biomass accumulation in roots. RDA confirmed the association between the responses obtained in vitro and the phenotypic performance in vivo, suggesting that the functional traits of the strains were decisive for the differences among treatments. The contrasting distribution of SBA and RBA likely reflects distinct biomass allocation strategies induced by each strain. The dissociation of SBA from the other variables in the RDA suggests the occurrence of an adaptive trade-off. In this strategy, the plant reduces biomass allocation to the shoot and prioritizes root growth, ensuring greater efficiency in water and nutrient acquisition under stress conditions, albeit at the expense of immediate shoot growth (Chieb and Gachomo 2023 ; Grover et al. 2021 ; Bektas et al. 2023 ). The positive correlation between asymbiotic nitrogen fixation and root variables reinforces the role of these bacteria in plant nutrition, while the association between IAA and RL, SL, and SD highlights the direct contribution of the phytohormone to cucumber growth under the tested conditions, identifying the inoculated treatments with the greatest agronomic potential. Nevertheless, as this study was conducted at an early stage under controlled conditions, further field trials are necessary to validate these effects and confirm strain efficiency across different environments and cropping systems. Conclusion These results highlight the potential of the phyllosphere of native semi-arid plants as a source for the development of new technologies aimed at sustainable agriculture. The integration of epiphytic microorganisms represents a promising tool to address the challenges posed by population growth and climate change. Brevibacillus sp. UPT4 exhibited the greatest improvements in cucumber seedlings development, promoting increases in shoot and root system length, thereby enhancing plant efficiency and resilience. Author contributions All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Ellie José Pereira and Vinícius de Souza. The first draft of the manuscript was written by Ellie José Pereira and Vinícius de Souza, and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript. Funding The authors declare that no funds, grants, or other support were received during the preparation of this manuscript. Data availability The authors confirm that the data supporting the findings of this study are available within the article. Declarations Ethics approval and consent to participate Not applicable. Competing interests The authors declare no competing interests. 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