https://hdl.handle.net/20.500.12008/26173 Incluye artículos, objetos de conferencias, seminarios y jornadas, reportes técnicos, comunicaciones y otros Sun, 02 Aug 2026 04:52:01 GMT 2026-08-02T04:52:01Z https://hdl.handle.net/20.500.12008/56217 Título: Comparative genomics of Pantoea allii lineages and distribution of ecologically relevant traits Autor: Shin, Gi Yoon; De Armas, Stefanie; Galván, Guillermo A.; Siri, María I.; Rojas, Mariah; Vinatzer, Boris A.; Asselin, Jo Ann E.; Stodghill, Paul; Zhao, Mei; Dutta, Bhabesh; Tambong, James; Kvitko, Brian H. Resumen: Pantoea allii, one of four Pantoea species known to cause onion centre rot, is infrequently isolated from onion compared to its closely related onion-pathogenic species in the same genus. To better understand the genomic diversity and genetic determinants of pathogenicity in this species, we analysed a collection of 38 P. allii strains isolated from 2 primary ecological niches, plants and rainwater, across North and South American and African continents using comparative genomics and phylogenetic approaches. Core-genome phylogeny, average nucleotide identity and gene presence–absence analyses revealed three genetically distinct lineages. All strains harboured conserved biosynthetic gene clusters (BGCs) for quorum sensing, carotenoid production, siderophores and thiopeptides. In contrast, two phosphonate BGCs, key determinants of onion pathogenicity, exhibited lineage-specific distributions. Onion-associated strains from lineages 1 and 2 carried the Halophos BGC responsible for onion tissue necrosis and also encoded the alt gene cluster that confers tolerance to thiosulfinates. Lineage 3 strains, isolated from both onion and rainwater, either lacked a phosphonate BGC entirely or possessed the HiVir phosphonate BGC. In addition, lineage 3 strains lacked the alt cluster altogether. The localization of these virulence genes in the genome varied, with Halophos integrated in the chromosome, HiVir encoded on the conserved Large Pantoea Plasmid, and alt located on small, variable plasmids (plasmid B). The type IV secretion system (T4SS) and type VI secretion system (T6SS) showed variable genomic architectures, with plasmid-borne T4SSs and two chromosomal T6SS loci differing in conservation and gene content. Additionally, conserved Pantailocin phage islands were detected in most genomes. Overall, this study reveals that while core metabolic and competitive traits are conserved across P. allii, virulence-associated loci display lineage-specific distribution, reflecting ecological differentiation and evolutionary plasticity within the species. Thu, 01 Jan 2026 00:00:00 GMT https://hdl.handle.net/20.500.12008/56217 2026-01-01T00:00:00Z https://hdl.handle.net/20.500.12008/56211 Título: Dual benefits of compost tea bacteria : boosting ‘San Andreas’ strawberries’ productivity and fruit quality Autor: Seimandi, Gisela M.; Garmendia, Gabriela; Nicolier, Juan G.; Favaro, María A.; Fernandez, Laura N.; Ruiz, Verónica E.; Vero, Silvana; Derita, Marcos G. Resumen: Bacteria represent promising tools for reducing the use of synthetic inputs in crop production. In this study, we evaluated the effects of two bacterial strains isolated from chicken compost tea—Bacillus licheniformis and Pseudomonas mendocina—on the yield and quality of strawberry. Experimental assays were conducted in two seasons (2023 and 2024) under macro-tunnel conditions, with the following treatments: control without applications (Con); commercial NPK fertilizer (FerC); application of B. licheniformis (BL) and P. mendocina (PM) solution in soil once a month. Both bacterial treatments enhanced soil properties. Fruit individual weight significantly increased in BL treatment compared to the control. Similar trends were observed for anthocyanin and ascorbic acid content (increases > 25%), as well as for antioxidant activity (increases of more than 20% and 13% for BL and PM, respectively). The differences were more significant in 2023. In addition, both strains showed positive in vitro results for phytase, siderophore, and IAA production (5.8–8.8 and 9.3–13 μg IAA/mL for BL and PM after 15 days). Although further field validation is required, these results indicate that bacteria (particularly B. licheniformis) show strong potential as bioinoculants to enhance the productivity and quality of strawberry. Thu, 01 Jan 2026 00:00:00 GMT https://hdl.handle.net/20.500.12008/56211 2026-01-01T00:00:00Z https://hdl.handle.net/20.500.12008/56198 Título: Early deficient lactation differentially affects neonatal thymic cortical development and humoral immune responses in rats Autor: Sánchez, María Belén; Michel Lara, María Cecilia; Germanó, María José; Neira, Flavia Judith; Viruel, Luciana Belén; Tomsich, Jacqueline Lisset; Rodríguez-Camejo, Claudio; Troncoso, Mariana; Pietrobon, Elisa Olivia; Soaje, Marta; Hernández, Ana; Jara, Evelyn L.; Valdez, Susana Ruth; Mackern-Oberti, Juan Pablo Resumen: Hypoprolactinemia (hypoPRL) disrupts lactation and compromises milk production. Although maternal milk is a critical source of nutrients and bioactive compounds for newborns, the consequences of deficient lactation based on reduced milk quantity on the offspring’s immune development remain incompletely understood. Therefore, this study aimed to elucidate how deficient lactation due to hypoPRL interferes with offspring immunity and development. Female Sprague Dawley (SD) and spontaneous hypoPRL Oncins France Colony A (OFA) rats were euthanized on day 2 of lactation to assess the impact of hypoPRL on serum, milk, and tissue samples. We demonstrated that early deficient lactation in the OFA model impaired maternal performance, leading to increased pup mortality during early lactation. OFA pups exhibited reduced body weight and weight gain, decreased cerebral weight and index, and an increased cephalization index. Thymic development was markedly altered, as evidenced by reduced thymus weight, area, and cortical extension. These structural changes were accompanied by increased thymic Rag 1 expression, suggesting altered lymphocyte development. In parallel, passive immune transfer was compromised, with reduced levels of OVA-specific immunoglobulin isotypes detected in pup serum, reflecting changes in milk-derived immune support. In summary, maternal hypoPRL during early lactation adversely affects offspring growth and thymic maturation with lasting consequences for neonatal immune maturation. This study provides a novel experimental framework to investigate the consequences of lactation deficiency with potential implications for understanding lactation insufficiency and its impact on neonatal immune exposure. Thu, 01 Jan 2026 00:00:00 GMT https://hdl.handle.net/20.500.12008/56198 2026-01-01T00:00:00Z https://hdl.handle.net/20.500.12008/56150 Título: Rapid detection of black pepper adulteration withendogenous and exogenous materials : assessment of benchtop and handheld infrared spectrometers Autor: Rentz, Paul; Mihailova, Alina; Heinzen, Horacio; Bergaentzlé, Martine; Ruhland, Elisa; Islam, Marivil D.; Hamed, Islam; Vlachou, Christina; Kelly, Simon; Ennahar, Said; Werner, Dalal Resumen: Black pepper is the most widely used spice crop globally and has significant economic value, making it a target for economically motivated adulteration. A wide range of organic and inorganic bulking materials has been used as adulterants in black pepper. Development of rapid non-targeted screening methods for use at different stages of the black pepper supply chain is extremely important for the identification and prevention of evolving fraudulent practices. This study has assessed the potential of benchtop Fourier Transform infrared with attenuated total reflectance (FTIR-ATR), benchtop Fourier Transform near-infrared (FT-NIR), and two handheld NIR spectrometers, coupled with chemometrics, for the discrimination of black pepper (Piper nigrum), pepper from other species and genera (non- Piper nigrum) and a broad range (n = 27) of endogenous and exogenous adulterants. Spiked samples were prepared to imitate pepper adulteration with seven different adulterants at five levels of adulteration (5%, 25%, 50%, 75%, 95% w/w). Orthogonal partial least squares discriminant analysis (OPLS-DA) achieved 100% total prediction accuracy for both FTIRATR and FT-NIR in differentiating authentic Piper nigrum and adulterant samples. The handheld microNIR 1700ES resulted in a 91.30% correct classification rate, while the SCiO model achieved 86.96% prediction accuracy. Detection of black pepper adulteration with multiple adulterants was performed using data-driven soft independent modelling of class analogy (DD-SIMCA). The highest performance of the DD-SIMCA model was achieved by FTIR-ATR (100% sensitivity and 100% specificity) followed by FT-NIR (98% sensitivity and 99% specificity). The handheld microNIR 1700ES resulted in 95% sensitivity and 90% specificity. This study demonstrated that FTIR-ATR and FT-NIR, coupled with DD-SIMCA, can effectively detect black pepper adulteration with multiple endogenous and exogenous adulterants. The handheld NIR (microNIR1700ES) clearly demonstrated the potential for rapid and effective verification of Piper nigrum authenticity outside the laboratory. Thu, 01 Jan 2026 00:00:00 GMT https://hdl.handle.net/20.500.12008/56150 2026-01-01T00:00:00Z