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Bacterial spot of tomato (BST), caused by Xanthomonas perforans, is an economically important disease of tomatoes in Florida. Due to the heavy reliance on copper-based bactericides for control of BST, copper-resistant strains of X. perforans are widely distributed in Florida, leading to reduced efficacy of copper-based bactericides for disease control. There is a need for alternative chemical control strategies to effectively manage this disease in tomato production. In this study, two small molecules, piperidine and pyrrolidine, were evaluated for their efficacy against the copper-resistant X. perforans strain GEV 485 in laboratory, greenhouse, and field experiments. In in vitro experiments, piperidine and pyrrolidine at concentrations as low as 2 mg/L and 16 mg/L, respectively, significantly (P<0.001) reduced bacterial populations within 4 h of incubation compared to the untreated control, while Kocide 3000, the grower copper-based bactericide standard, at 0.9 g/L and 2.1 g/L (full label rate) did not significantly reduce bacterial populations. When tested as foliar sprays in the greenhouse, pyrrolidine at 128 mg/L significantly (P <0.001) reduced disease severity compared to the untreated control, with an equivalent efficacy to Kocide 3000 (copper hydroxide at 2.1 g/L). Kocide 3000 at 1.0 g/L, in combination with piperidine at 64 mg/L and pyrrolidine at 64 and 128 mg/L significantly improved the efficacy in disease control compared to untreated controls and Kocide 3000 at 1.0 g/L alone. In field trials, both small molecules demonstrated equivalent or superior efficacy to ManKocide (copper hydroxide + mancozeb) against X. perforans compared to the untreated control. This study demonstrated for the first time the potential of piperidine and pyrrolidine for controlling bacterial spot of tomato.
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We report the draft genome assembly of strain 4866-2_S43 isolated from a eucalyptus lesion in Argentina and what until recently was caused by Xanthomonas citri pv. eucalyptorum (Xce). The genome size is 5â188â607 bp, with a G+C content of 64.66%. Comparative analysis reveals that the closest relative of strain 4866-2_S43 is Xce LPF 602, isolated in Brazil. Comparison of the whole genome sequences revealed an average nucleotide identity (ANI) of 99.96% between the two strains. ANIs were determined between the whole genome sequence of strain 4866-2_S43 and the genomes of all currently validated Xanthomonas spp. These results revealed that strain 4866-2_S43 shared >95% similarity with X. citri pv. citri and X. citri pv. phaseoli, and <95% with X. euvesicatoria pv. alfalfae, X. euvesicatoria pv. perforans, and X. euvesicatoria pathovars euvesicatoria and eucalyptii.
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BACKGROUND AND OBJECTIVE: Radical Cystectomy is indicated in muscle-invasive bladder cancer and select cases of nonmuscle invasive bladder cancer. Women often undergo additional reproductive organ removal, greatly impacting sexual function and quality of life. Pelvic organ-preserving radical cystectomy aims to mitigate these effects, but its oncologic outcomes are not well-defined. This presents a meta-analysis of available literature on oncological outcomes of pelvic organ-preserving radical cystectomy in women with muscle invasive disease. METHODS: A systematic search across PubMed, Web of Science, Scopus, and Google Scholar was performed to identify studies comparing oncological outcomes between pelvic organ-preserving radical cystectomy and standard radical cystectomy in women with muscle-invasive bladder cancer or high-risk or recurrent nonmuscle invasive cancer. The search included English or Spanish studies, statistically comparing overall survival, cancer-specific survival, and recurrence-free survival. Statistical analysis used Review Manager, employing fixed or random-effects models based on heterogeneity. KEY FINDINGS AND LIMITATIONS: Six retrospective studies met inclusion criteria, totaling 597 patients of which 303 received pelvic organ-preserving radical cystectomy and 294 received standard radical cystectomy. Overall Survival was not different between the 2 groups (HR 1.05 [0.77, 1.43]; Pâ¯=â¯0.77). Cancer-Specific Survival also was found to be not different between the 2 groups (HR 1.27 [0.86, 1.87]; Pâ¯=â¯0.22). Additionally, recurrence-free survival was not different between the 2 groups (HR 0.85 [0.41, 1.75]; Pâ¯=â¯0.65. Four of the included studies exhibited a moderate risk of bias, with 1 study demonstrating low risk and the remaining study manifesting a serious risk of bias. CONCLUSION: The comparison showed no significant differences in overall survival, cancer-specific survival, or recurrence-free survival rates.
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OBJECTIVE: To assess the unique risks of prostate cancer among U.S. veterans, and to advocate for improved care by raising awareness of the gaps in current AUA guidelines that do not address the specific needs of military personnel and veterans. METHODS: Ovid interface, Google Scholar, PubMed, and Medline were searched for studies investigating prostate cancer in veterans published between 1975 and 2023. Search terms: "veteran", "military", "molecular markers", "prostate cancer", "prostate cancer risk", and "military exposure" were used. Articles meeting inclusion criteria underwent analysis, data synthesis, and meta-analysis where applicable. RESULTS: Results from forty-five articles indicate a significant increase in prostate cancer risk associated with exposure to Agent Orange (OR 1.97 [95% CI: 1.64 - 2.37], p < 0.00001), aromatic hydrocarbons (OR 1.14 [95% CI: 1.01 - 1.28], p = 0.03), and a slight increase with cadmium exposure (OR 1.03 [95% CI: 0.96 - 1.09], p = 0.42). While some evidence suggests an association between Camp Lejeune and prostate cancer risk in retrospective cohort studies, logistical regression analysis study did not entirely substantiate this relationship. CONCLUSIONS: This review identifies several exposures that elevate prostate cancer risk. Military veterans should be further questioned about their exposures and potentially treated as a high-risk screening group. Further research is warranted to strengthen these associations, as the current evidence remains limited.
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BACKGROUND: Understanding the functionality, benefits, and limitations of generative artificial intelligence (GAI) is important for nurses and nursing students. PURPOSE: This study explored nursing students' perspectives on GAI after a guided learning activity in which students used a chatbot to answer a clinical question. METHODS: A qualitative approach using reflective thematic analysis of written reflections was conducted with 19 nursing students in a nursing baccalaureate completion program. RESULTS: Student reflections demonstrated 4 themes: surprisingly familiar; the importance of critical thinking and external validation; a good summary lacking depth and nuance; and cautious optimism. Two subthemes were also identified: validation is time-consuming and a new perspective. CONCLUSIONS: Learning activities using GAI influence students' knowledge and attitudes and instill critical awareness of the advantages and limitations of this technology. Additional emphasis on bias in GAI is needed when teaching about AI.
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Bacterial leaf spot of pepper (BSP), primarily caused by Xanthomonas euvesicatoria (Xe), poses a significant challenge to pepper production worldwide. Despite its impact, the genetic diversity of this pathogen remains underexplored, which limits our understanding of its population structure. To bridge this knowledge gap, we conducted a comprehensive analysis using 103 Xe strains isolated from pepper in southwest Florida to characterize genomic and type III effector (T3E) variation in this population. Phylogenetic analysis of core genomes revealed a major distinct genetic lineage associated with amylolytic activity. This amylolytic lineage was represented in Xe strains globally. Molecular clock analysis dated the emergence of amylolytic strains in Xe to around 1972. Notably, non-amylolytic strains possessed a single base pair frameshift deletion in the âº-amylase gene yet retained a conserved C-terminus. GUS assay revealed the expression of two open reading frames in non-amylolytic strains, one at the N-terminus and another that starts 136 base pairs upstream of the âº-amylase gene. Analysis of T3Es in the Florida Xe population identified variation in 12 effectors, including two classes of mutations in avrBs2 that prevent AvrBs2 from triggering a hypersensitive response in Bs2-resistant pepper plants. Knowledge of T3E variation could be used for effector-targeted disease management. This study revealed previously undescribed population structure in this economically important pathogen.IMPORTANCEBacterial leaf spot (BSP), a significant threat to pepper production globally, is primarily caused by Xanthomonas euvesicatoria (Xe). Limited genomic data has hindered detailed studies on its population diversity. This study analyzed the whole-genome sequences of 103 Xe strains from peppers in southwest Florida, along with additional global strains, to explore the pathogen's diversity. The study revealed two major distinct genetic groups based on their amylolytic activity, the ability to break down starch, with non-amylolytic strains having a mutation in the âº-amylase gene. Additionally, two classes of mutations in the avrBs2 gene were found, leading to susceptibility in pepper plants with the Bs2 resistance gene, a commercially available resistance gene for BSP. These findings highlight the need to forecast the emergence of such strains, identify genetic factors for innovative disease management, and understand how this pathogen evolves and spreads.
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Capsicum , Filogenia , Doenças das Plantas , Xanthomonas , Capsicum/microbiologia , Doenças das Plantas/microbiologia , Xanthomonas/genética , Xanthomonas/enzimologia , Xanthomonas/classificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Amilases/genética , Amilases/metabolismo , Variação Genética , FloridaRESUMO
Metastatic urothelial carcinoma (muC) has historically had few effective therapeutic options. Recently, immune checkpoint inhibitors (ICIs), were introduced as therapeutic options for cisplatin-ineligible patients, however, direct head-to-head trials comparing these treatments are lacking. To address this gap, this study employs a Bayesian framework to indirectly compare the performance of ICIs as first-line agents for muC. A systematic review was performed to identify randomized controlled trials evaluating different ICI for mUC. Data was inputted into Review Manager 5.4 for pairwise meta-analysis. Data was then used to build a network in R Studio. These networks were used to model 200,000 Markov Chains via MonteCarlo sampling. The results are expressed as hazard ratios (HR) with 95% credible intervals (CrI). Six studies with 5,449 patients were included, 3,255 received ICI monotherapy or combination. Moreover, a total of 3,006 had PD-L1 positive tumors and 2,362 were PD-L1 negative. Median overall survival (OS) ranged from 12.1 to 31.5 months across the studies, with the combination of enfortumab vedotin and pembrolizumab demonstrating the most substantial reduction in the risk of death (HR 0.47 [95% CrI: 0.38, 0.58]), followed by avelumab monotherapy (HR 0.69 [95% CrI: 0.56, 0.86]). The limitations of this network meta-analysis include variability in study follow-up duration, lack of standardized methods for assessing PD-L1 positivity, and potential bias introduced by control arms with poorer survival outcomes across included trials. The enfortumab vedotin/pembrolizumab combination significantly improved survival and response rates. Avelumab showed notable single-agent activity. These findings provide a valuable framework to guide clinical decision-making and highlight priority areas for future research, including biomarker refinement and novel combination strategies to enhance antitumor immunity in this challenging malignancy.
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Teorema de Bayes , Carcinoma de Células de Transição , Inibidores de Checkpoint Imunológico , Metanálise em Rede , Humanos , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/secundário , Inibidores de Checkpoint Imunológico/uso terapêutico , Metástase Neoplásica , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Neoplasias Urológicas/tratamento farmacológico , Neoplasias Urológicas/patologiaRESUMO
Type III effectors (T3Es) are major determinants of Xanthomonas virulence and targets for resistance breeding. XopJ2 (synonym AvrBsT) is a highly conserved YopJ-family T3E acquired by X. perforans, the pathogen responsible for bacterial spot disease of tomato. In this study, we characterized a new variant (XopJ2b) of XopJ2, which is predicted to have a similar three-dimensional (3D) structure as the canonical XopJ2 (XopJ2a) despite sharing only 70% sequence identity. XopJ2b carries an acetyltransferase domain and the critical residues required for its activity, and the positions of these residues are predicted to be conserved in the 3D structure of the proteins. We demonstrated that XopJ2b is a functional T3E and triggers a hypersensitive response (HR) when translocated into pepper cells. Like XopJ2a, XopJ2b triggers HR in Arabidopsis that is suppressed by the deacetylase, SOBER1. We found xopJ2b in genome sequences of X. euvesicatoria, X. citri, X. guizotiae, and X. vasicola strains, suggesting widespread horizontal transfer. In X. perforans, xopJ2b was present in strains collected in North America, Africa, Asia, Australia, and Europe, whereas xopJ2a had a narrower geographic distribution. This study expands the Xanthomonas T3E repertoire, demonstrates functional conservation in T3E evolution, and further supports the importance of XopJ2 in X. perforans fitness on tomato. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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In Florida, angular leaf spot, caused by Xanthomonas fragariae, was the only known bacterial disease in strawberry, which is sporadic and affects the foliage and calyx. However, from the 2019-2020 to 2023-2024 Florida strawberry seasons, unusual bacterial-like symptoms were observed in commercial farms, with reports of up to 30â% disease incidence. Typical lesions were water-soaked and angular in early stages that later became necrotic with a circular-ellipsoidal purple halo, and consistently yielded colonies resembling Pseudomonas on culture media. Strains were pathogenic on strawberry, fluorescent, oxidase- and arginine-dihydrolase-negative, elicited a hypersensitive reaction on tobacco, and lacked pectolytic activity. Although phenotypic assays, such as fatty acid methyl profiles and Biolog protocols, placed the strains into the Pseudomonas group, there was a low similarity at the species level. Further analysis using 16S rRNA genes, housekeeping genes, and whole genome sequencing showed that the strains cluster into the Pseudomonas group but do not share more than 95â% average nucleotide identity compared to representative members. Therefore, the genomic and phenotypic analysis confirm that the strains causing bacterial spot in strawberry represent a new plant pathogenic bacterial species for which we propose the name Pseudomonas fragariae sp. nov. with 20-417T (17T=LMG 32456T=DSM 113340 T) as the type strain, in relation to Fragaria×ananassa, the plant species from which the pathogen was first isolated. Future work is needed to assess the epidemiology, cultivar susceptibility, chemical sensitivity, and disease management of this possible new emerging strawberry pathogen.
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Técnicas de Tipagem Bacteriana , DNA Bacteriano , Fragaria , Filogenia , Doenças das Plantas , Folhas de Planta , Pseudomonas , RNA Ribossômico 16S , Fragaria/microbiologia , RNA Ribossômico 16S/genética , Doenças das Plantas/microbiologia , Pseudomonas/genética , Pseudomonas/isolamento & purificação , Pseudomonas/classificação , DNA Bacteriano/genética , Folhas de Planta/microbiologia , Florida , Análise de Sequência de DNA , Sequenciamento Completo do Genoma , Ácidos Graxos , Genes Essenciais/genéticaRESUMO
The United States Veterans Affairs (VA) Health Care System has a strong history of conducting impactful oncology randomized clinical trials (RCTs). We developed a phase II/III RCT to test the use of metastasis-directed therapy in Veterans with oligometastatic prostate cancer (OMPC)-the first VA RCT in OMPC that leverages novel imaging and advanced radiotherapy techniques. To accomplish this, we developed a clinical trial network to conduct the study. In this manuscript, we describe several challenges we encountered in study development/conduct and our strategies to address them, with the goal of helping investigators establish robust study networks to conduct clinical trials. In the study start-up, we encountered challenges in timely site activation, and leveraged project management to maximize efficiency. Additionally, there were several changes in the clinical paradigms in imaging and treatment that led to protocol amendments to ensure maximum equipoise, recruitment, and impact of the study. Specifically, we amended the trial to add de novo OMPC patients (from initially only recurrent OMPC) and expanded the study to allow up to 10 metastases (from initially five). Finally, in order to maintain local study team engagement, we developed initiatives to maximize collaboration and add value to the overall clinical program through study participation.
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United States Department of Veterans Affairs , Humanos , Estados Unidos , Masculino , Oncologia/métodos , Neoplasias da Próstata/terapia , Veteranos , Ensaios Clínicos como AssuntoRESUMO
Impaired cerebral glucose metabolism is a pathologic feature of Alzheimer's disease (AD), with recent proteomic studies highlighting disrupted glial metabolism in AD. We report that inhibition of indoleamine-2,3-dioxygenase 1 (IDO1), which metabolizes tryptophan to kynurenine (KYN), rescues hippocampal memory function in mouse preclinical models of AD by restoring astrocyte metabolism. Activation of astrocytic IDO1 by amyloid ß and tau oligomers increases KYN and suppresses glycolysis in an aryl hydrocarbon receptor-dependent manner. In amyloid and tau models, IDO1 inhibition improves hippocampal glucose metabolism and rescues hippocampal long-term potentiation in a monocarboxylate transporter-dependent manner. In astrocytic and neuronal cocultures from AD subjects, IDO1 inhibition improved astrocytic production of lactate and uptake by neurons. Thus, IDO1 inhibitors presently developed for cancer might be repurposed for treatment of AD.
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Doença de Alzheimer , Peptídeos beta-Amiloides , Astrócitos , Glucose , Glicólise , Hipocampo , Indolamina-Pirrol 2,3,-Dioxigenase , Cinurenina , Neurônios , Animais , Humanos , Masculino , Camundongos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Astrócitos/metabolismo , Cognição/efeitos dos fármacos , Modelos Animais de Doenças , Glucose/metabolismo , Glicólise/efeitos dos fármacos , Hipocampo/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Cinurenina/metabolismo , Ácido Láctico/metabolismo , Potenciação de Longa Duração , Memória/efeitos dos fármacos , Transportadores de Ácidos Monocarboxílicos/metabolismo , Neurônios/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Proteínas tau/metabolismo , Triptofano/metabolismoRESUMO
Many phytopathogenic bacteria require a type three secretion system (TTSS) to activate effector triggered immunity (ETI). We identified a calcium binding protein, EfhXXfa, in the citrus pathogen, X. citri subsp. aurantifolii, that does not require a TTSS to activate reactive oxygen species (ROS) and elicit a hypersensitive reaction (HR) in tomato leaves following infection. Purified, recombinant EfhXXfa was shown to bind two moles of calcium per mole of protein, whereas mutation of the first of two EF-hands did not bind calcium . EfhXXfa expression was determined to be inducible in hrp-inducing medium. Additionally, growth of X. perforans transconjugants with and without the efhXXfa gene in hrp-inducing medium differed in intracellular calcium concentration; the transconjugant without efhXXfa yielded higher cell pellet masses and higher increased intracellular calcium concentrations relative to cells expressing EfhXXfa. An EfhXXfa homolog, EfhXXe, present in the pepper pathogen, X. euvesicatoria, when expressed in the tomato pathogen, X. perforans, triggered ROS production and an HR in tomato leaves and is a host-limiting factor. Interestingly, all tested X. perforans and X. euvesicatoria strains pathogenic on tomato contain a stop codon immediately upstream of the first EF-hand domain in the efhXXe gene, whereas most X. euvesicatoria strains pathogenic on pepper do not.
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Changes in the structure of bone can occur in space as an adaptive response to microgravity and on Earth due to the adaptive effects to exercise, to the aging of bone cells, or to prolonged disuse. Knowledge of cell-mediated bone remodeling on Earth informs our understanding of bone tissue changes in space and whether these skeletal changes might increase the risk for fractures or premature osteoporosis in astronauts. Comparisons of skeletal health between astronauts and aging humans, however, may be both informative and misleading. Astronauts are screened for a high level of physical fitness and health, are launched with high bone mineral densities, and perform exercise daily in space to combat skeletal atrophy as an adaptive response to reduced weight-bearing function, while the elderly display cellular and tissue pathology as a response to senescence and disuse. Current clinical testing for age-related bone change, applied to astronauts, may not be sufficient for fully understanding risks associated with rare and uniquely induced bone changes. This review aims to (i) highlight cellular analogies between spaceflight-induced and age-related bone loss, which could aid in predicting fractures, (ii) discuss why overreliance on terrestrial clinical approaches may miss potentially irreversible disruptions in trabecular bone microarchitecture induced by spaceflight, and (iii) detail how the cellular effects of the bisphosphonate class of drugs offer a prophylactic countermeasure for suppressing the elevated bone resorption characteristically observed during long-duration spaceflights. Thus the use of the bisphosphonate will help protect the bone from structural changes while in microgravity either along with exercise or alone when exercise is not performed, e.g. after an injury or illness.
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Astronautas , Difosfonatos , Voo Espacial , Humanos , Difosfonatos/farmacologia , Difosfonatos/uso terapêutico , Osteoporose , Ausência de Peso/efeitos adversos , Densidade Óssea/efeitos dos fármacosRESUMO
OBJECTIVE: To investigate potential carcinogenic exposures in military personnel that are implicated in the development of bladder cancer. METHODS: This systematic review aimed to evaluate the association between specific military exposures and bladder cancer risk among veterans. PubMed, Scopus, and Ovid MEDLINE databases were searched in December 2023 for relevant articles. Inclusion criteria comprised retrospective cohort studies, reviews, and observational studies documenting bladder cancer incidence among military populations exposed to specific agents. A total of 25 studies, involving 4,320,262 patients, met the inclusion criteria. Data extraction followed PRISMA guidelines, and a random-effects model was used for data synthesis. RESULTS: The meta-analysis revealed significant associations between exposure to Agent Orange (HR 1.17 [95% CI: 1.01-1.36], P < .00001) and depleted uranium (HR 2.13 [95% CI: 1.31-3.48], P = .002) with increased bladder cancer risk among veterans. Contaminated drinking water showed a trend towards increased risk (HR 1.25 [95% CI: 0.97-1.61], P = .08). CONCLUSION: The findings suggest a possible association between specific military exposures and heightened bladder cancer risk among veterans, emphasizing the necessity for targeted screening protocols and preventive measures. Further research is essential to identify specific carcinogenic agents and prevalence of exposures among veterans, enabling more effective prevention and management strategies.
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INTRODUCTION: Mild cognitive impairment (MCI) is a significant public health concern and a potential precursor to Alzheimer's disease (AD). This study leverages electronic health record (EHR) data to explore rural-urban differences in MCI incidence, risk factors, and healthcare navigation in West Michigan. METHODS: Analysis was conducted on 1,528,464 patients from Corewell Health West, using face-to-face encounters between 1/1/2015 and 7/31/2022. MCI cases were identified using International Classification of Diseases (ICD) codes, focusing on patients aged 45+ without prior MCI, dementia, or AD diagnoses. Incidence rates, cumulative incidences, primary care physicians (PCPs), and neuropsychology referral outcomes were examined across rural and urban areas. Risk factors were evaluated through univariate and multivariate Cox regression analyses. The geographic distribution of patient counts, hospital locations, and neurology department referrals were examined. RESULTS: Among 423,592 patients, a higher MCI incidence rate was observed in urban settings compared to rural settings (3.83 vs. 3.22 per 1,000 person-years). However, sensitivity analysis revealed higher incidence rates in rural areas when including patients who progressed directly to dementia. Urban patients demonstrated higher rates of referrals to and completion of neurological services. While the risk factors for MCI were largely similar across urban and rural populations, urban-specific factors for incident MCI are hearing loss, inflammatory bowel disease, obstructive sleep apnea, insomnia, being African American, and being underweight. Common risk factors include diabetes, intracranial injury, cerebrovascular disease, coronary artery disease, stroke, Parkinson's disease, epilepsy, chronic obstructive pulmonary disease, depression, and increased age. Lower risk was associated with being female, having a higher body mass index, and having a higher diastolic blood pressure. DISCUSSION: This study highlights rural-urban differences in MCI incidence and access to care, suggesting potential underdiagnosis in rural areas likely due to reduced access to specialists. Future research should explore socioeconomic, environmental, and lifestyle determinants of MCI to refine prevention and management strategies across geographic settings. Highlights: Leveraged EHRs to explore rural-urban differences in MCI in West Michigan.Revealed a significant underdiagnosis of MCI, especially in rural areas.Observed lower rates of neurological referrals and completions for rural patients.Identified risk factors specific to rural and urban populations.
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The emergence of plant pathogens is often associated with waves of unique evolutionary and epidemiological events. Xanthomonas hortorum pv. gardneri is one of the major pathogens causing bacterial spot disease of tomatoes. After its first report in the 1950s, there were no formal reports on this pathogen until the 1990s, despite active global research on the pathogens that cause tomato and pepper bacterial spot disease. Given the recently documented global distribution of X. hortorum pv. gardneri, our objective was to examine genomic diversification associated with its emergence. We sequenced the genomes of X. hortorum pv. gardneri strains collected in eight countries to examine global population structure and pathways of emergence using phylodynamic analysis. We found that strains isolated post-1990 group by region of collection and show minimal impact of recombination on genetic variation. A period of rapid geographic expansion in X. hortorum pv. gardneri is associated with acquisition of a large plasmid conferring copper tolerance by horizontal transfer and coincides with the burgeoning hybrid tomato seed industry through the 1980s. The ancestry of X. hortorum pv. gardneri is consistent with introduction to hybrid tomato seed production and dissemination during the rapid increase in trade of hybrid seeds. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.