Macrophomina phaseolina: General Characteristics of Pathogenicity and Methods of Control

Macrophomina phaseolina is a generalist soil-borne fungus present all over the world. It cause diseases such as stem and root rot, charcoal rot and seedling blight. Under high temperatures and low soil moisture, this fungus can cause substantial yield losses in crops such as soybean, sorghum and groundnut. The wide host range and high persistence of M. phaseolina in soil as microsclerotia make disease control challenging. Therefore, understanding the basis of the pathogenicity mechanisms as well as its interactions with host plants is crucial for controlling the pathogen. In this work, we aim to describe the general characteristics and pathogenicity mechanisms of M. phaseolina, as well as the hosts defense response.We also review the current methods and most promising forecoming ones to reach a responsible control of the pathogen, with minimal impacts to the environment and natural resources.Instituto de Patología VegetalFil: Marquez, Nathalie. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentina.Fil: Marquez, Nathalie. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFYMA); ArgentinaFil: Giachero, María Lorena. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Giachero, María Lorena.Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFYMA); ArgentinaFil: Declerck, Stéphane. Université Catholique de Louvain. Earth and Life Institute. Applied Microbiology. Mycology; BélgicaFil: Ducasse, Daniel Adrian. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentin

Soybean responseto initial stage of Fusarium virguliforme infection

Fusarium virguliforme causes the Sudden Death Syndrome, an important disease in soybean crops. In this work, we investigated the defensive response mechanisms in soybean root, at cell wall level, during F. virguliforme infection using an in vitro culture system. We measured total root lignin content by the acetyl bromide method and estimated the in-situ lignin and suberin deposition by confocal microscopy on local and systemic root tissues, i.e. adjacent and distant to the pathogen entry site respectively. Moreover, the expression dynamics of phenylalanine ammonia lyase (PAL), shikimate/quinate hydroxycinnamoyltransferase (HCT) and cinnamyl alcohol dehydrogenase (CAD) was evaluated by real-time quantitative PCR. The results showed that, although the most significant increment of lignin deposition was observed in the epidermal cells of local tissues, F. virguliforme also induced lignin deposition changes in a sistemic fashion. In fact, inoculated plants presented a higher deposition of lignin in hypodermis and cortex than the control ones, independently of the distance from the inoculum source, while suberin deposition was higher in local zones. Moreover, the gene expression analysis showed an up-regulation of PAL, HCT and CAD genes after the inoculation with the pathogen, which correlates with the cell wall modifications observed in the local tissues. The results presented here suggest that the increase in lignin and suberin deposition during soybean root/F. virguliforme interaction is probably a strategy not only to stop the pathogen entrance, but to provide the plant more time to prepare its defences as well.Instituto de Patología VegetalFil: Giachero, María Lorena. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Marquez, Nathalie. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Ortega, Leandro Ismael. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Ducasse, Daniel Adrian. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentin

Transcriptome analysis of mycorrhizal and nonmycorrhizal soybean plantlets upon infection with Fusarium virguliforme, one causal agent of sudden death syndrome

Soilborne pathogens represent a threat to agriculture causing important yield losses. Sudden death syndrome (SDS) of soybean is a severe disease caused by a complex of Fusarium species. This pathosystem has been widely investigated and several strategies have been proposed to manage SDS. Although a decrease in symptoms and in the level of root tissue infection, particularly by F. virguliforme, was observed in the presence of arbuscular mycorrhizal fungi (AMF), biological control based on AMF has received less attention. Here, the results are reported of transcriptional analysis of mycorrhizal versus nonmycorrhizal soybean plantlets infected by F. virguliforme, grown under strict in vitro culture experimental conditions. Important transcriptional reprogramming was detected following infection by the pathogen. Results revealed 1768 and 967 differentially expressed genes in the AMF-colonized (+AMF+Fv) and noncolonized (−AMF+Fv) plants, respectively. Major transcriptional changes corresponded to defence response-related genes belonging to secondary metabolism, stress and signalling categories. The +AMF+Fv treatment showed the largest number of up-regulated genes related to defence, such as those encoding disease resistance proteins, WRKY transcription factors, auxins, receptors kinases and proteases. Only a few genes had primed expression in the +AMF+Fv treatment, such as those encoding a thaumatin-like protein (TLP) and a pleiotropic drug resistance (PDR) protein. Moreover, +AMF+Fv showed a significantly greater number of down-regulated genes related to cell wall modification and peroxidases than the –AMF+Fv treatment. This detailed investigation increases knowledge of transcriptional changes and potential metabolic pathways involved in the enhanced resistance or tolerance of mycorrhizal plants to infection by F. virguliforme.Fil: Marquez, Nathalie. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigaciones Agropecuarias. Unidad de Fitopatologia y Modelizacion Agricola. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Unidad de Fitopatologia y Modelizacion Agricola.; ArgentinaFil: Giachero, María Lorena. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Fitopatología y Fisiología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gallou, A.. Centro Nacional de Referencia de Control Biológico; MéxicoFil: Debat, Humberto Julio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Fitopatología y Fisiología Vegetal; ArgentinaFil: Declerck, S,. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; ArgentinaFil: Ducasse, Daniel Adrián. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentin

Impacto de nanofertilizantes en la micorrización y crecimiento inicial de Medicago truncatula

PosterSe ha corroborado que, la aplicación de nanopartículas de selenita (NPS) mejora no sólo el desarrollo vegetal sino también beneficia el microbioma del suelo .Instituto de Fisiología y Recursos Genéticos VegetalesFil: Giachero, María Lorena. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Giachero, María Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); ArgentinaFil: Marquez, Nathalie. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Marquez, Nathalie. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); ArgentinaFil: Ranieri, Veronica Valeria. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Ranieri, Veronica Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); ArgentinaFil: Ciacci, María Belén. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Ciacci, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Estudios Agropecuarios (UDEA); Argentin

Manejo de enfermedades y mejora de la salud de las plantas mediante la utilización de microorganismos. Caso 2: relevamiento de las especies de hongos micorrícicos presentes en el suelo y asociadas a raíces de cebollas en diferentes rotaciones de cultivos y su efecto como agentes de bioprotección frente a enfermedades.

La diversidad de los microorganismos del suelo es esencial para la sustentabilidad de los sistemas productivos además de ser un indicador integral de la condición de los ecosistemas.Entre estos microorganismos los hongos micorrícicos(HMA)cumplen un papel fundamental, al incrementar la tolerancia de las plantas a estrés bióticos y abióticos. Los sistemas de labranza tradicionales y el monocultivo tienden a disminuir su diversidad y su población, mientras que las rotaciones de cultivos y el establecimiento de praderas hacen incrementar esta diversidad. Phoma terrestris es un hongo patógeno de suelo, agente causal de la “raíz rosada de la cebolla”, enfermedad limitante para dicho cultivo. Su control es muy difícil, dado que el patógeno sobrevive en el suelo varias campañas agrícolas, tiene un amplio rango de hospedantes y no existen variedades con buen comportamiento frente a los aislamientos argentinos. El presente proyecto propone la determinación biomolecular de los HMA presentes en el suelo y en asociación a las raíces de la cebolla, el estudio de la variaciones producidas en la flora micorríca bajo diferentes rotaciones, la determinación en la sanidad de la cebolla en las diferentes secuencias de cultivo y la evaluación de la capacidad de los mismos para atenuar los efectos deletéreos de P. terrestri

First report of Xanthomonas prunicola causing bacterial leaf streaks on wheat in Argentina

Since 2018, bacterial-like symptoms, such as leaf streaks were observed on wheat plants (Triticum aestivum L.) in Córdoba province in Argentina, with 1 to 5% of disease incidence. Samples of wheat stem and spike collected in a trial of varieties for summer/autumn sowing in the experimental field of the INTA Marcos Juárez were disinfected, washed and macerated in mortars with sterile distilled water and extracts were streaked on Luria-Bertani (LB) agar. After 48 h incubation at 28 °C, circular, mucoid, convex, and cream colonies were observed and pure cultures were transferred to LB medium for further identification tests. Biochemical tests corroborated the detection of a Gram-negative bacillus. Conventional PCR was performed using DNA isolate from pure cultures and general primers for various species of genera Xanthomonas (Maes 1993) and Pseudomonas (Mulet et al. 2010). An isolate (Arg-1), with cream colored colonies was positive using general primers for Xanthomonas sp (amplified fragment of 444 bp). A bacterial suspension containing 108 CFU mL−1 grown for 48 h on LB medium at 28 °C was injected into three-week-old leaves of wheat plants to fulfill Koch’s postulates. After 5 days, plants showed symptoms of chlorosis, streaks and then necrosis on the leaves. The bacteria were re-isolated from the inoculated plants, showing same symptoms observed in the original plants. Negative control plants, inoculated with sterile water remained without symptoms. The amplified 444 bp fragment described above was sequenced by the Sanger method (GenBank accession OM972662), as well as another 757 bp fragment amplified with universal primers that amplify the partial 16S rDNA gene (GenBank accession OM972661). Analyses of these sequences, as well as the protein profile of the isolate obtained by matrix assisted laser desorption/ionization time of-flight mass spectrometry (MALDI-TOF MS) Bruker Biotyper, allowed to identify only the genus Xanthomonas. With the purpose of determine the species status, the complete genome of isolate Arg-1 was sequenced using Oxford Nanopore Technologies (ONT). Total gDNA was isolate from pure cultures using a commercial kit (Wizard Genomic DNA Purification Kit, Promega). gDNA library was constructed using Ligation Sequencing Kit (SQK-LSK109) and sequenced using ONT platform on a MinION 1kb device. Raw basecalled sequences were filtered using Filtlong and assembled using Trycycler. The genome was assembled in a single contig comprising 5.410.641 bp with 4740 predicted CDSs and 63.9% GC content. Genome sequence was deposited in GenBank under accession number CP094827 and SRA data SRX14635308. Whole-genome Average Nucleotide Identity (ANI) analysis showed values of ~ 97% against the reference genomes of Xanthomonas prunicola (PHKX01.1, PHKV01.1 and PHKW01.1) and 100% in complete 16S rRNA gene sequences (1547 bp). These findings suggest that a new wheat pathogen within the genus Xanthomonas is present in Argentina, as well as was reported in Uruguay and USA (Clavijo et al. 2021). To our knowledge, this is the first report of X. prunicola affecting wheat in Argentina and the first complete genome registered for this specie. Accurate and specific diagnostics are required for the detection of X. prunicola in wheat crops to implement correct prevention and control strategies to this disease, avoiding the dissemination in lots where it has not yet been found.Instituto de Patología VegetalFil: Martino, Julia Andrea. Fondo para la Investigación Científica y Tecnológica (FONCYT); ArgentinaFil: Martino, Julia Andrea. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Fernandez, Franco Daniel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Fernandez, Franco Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); ArgentinaFil: Pozzi, Elizabeth Alicia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juárez; ArgentinaFil: Alberione, Enrique Javier. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juárez; ArgentinaFil: Bainotti, Carlos Tomas. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juárez; ArgentinaFil: Marquez, Nathalie. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Marquez, Nathalie. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); ArgentinaFil: Tolocka, Patricia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Tolocka, Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); ArgentinaFil: Salines, Nicolas. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juárez; ArgentinaFil: Gomez, Dionisio Tomas. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juárez; ArgentinaFil: Donaire, Guillermo Manuel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juárez; ArgentinaFil: Conci, Luis Rogelio. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Conci, Luis Rogelio. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); ArgentinaFil: Alemandri, Vanina Maria. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Alemandri, Vanina Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); Argentin

¿Nueva problemática sanitaria asociada a bacteria fitopatógena gram-positiva en trigo? [resumen]

A nivel mundial, se han descripto numerosas bacterias fitopatógenas en trigo (Triticum aestivum L.) responsables de ocasionar mermas en el rendimiento de este cultivo. Si bien la mayoría de ellas pertenecen a géneros de bacterias Gram-negativas, se ha indicado que Clavibacter michiganensis subsp. tessellarius (Cmt), bacteria Gram-positiva, afecta a este cereal, provocando síntomas como pequeñas lesiones amarillas con márgenes indefinidos distribuidas por toda la hoja, dando la apariencia de un mosaico. Una característica epidemiológica importante de Cmt es que se transmite por semilla. El objetivo de este trabajo fue el aislamiento de bacterias fitopatógenas en semillas de trigo provenientes de lotes de producción en la localidad de Manfredi, en la provincia de Córdoba, con síntomas similares a los descriptos para Cmt. Las semillas fueron desinfectadas, enjuagadas y molidas en morteros estériles. Posteriormente, se sembró 1 ml del extracto en medio de cultivo Luria-Bertani (LB) y conservadas a 28ºC. De dichos aislamientos, se observaron colonias aisladas con características morfológicas similares a las descriptas para Cmt. Se efectuaron pruebas bioquímicas que corroboraron la detección de un bacilo Gram-positivo. Respecto a pruebas moleculares, se realizaron PCR convencionales a partir de ADN de cultivos puros con el empleo de cebadores universales para bacterias que amplifican la región intergénica del 16S. Los productos de PCR fueron secuenciados por el método de Sanger. También, se realizaron los postulados de Koch, inoculando en hojas una suspensión bacteriana de concentración conocida (> a 108 UFC/ml).Instituto de Patología VegetalFil: Marquez, Nathalie. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFYMA); Argentina.Fil: Tolocka, Patricia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFYMA); Argentina.Fil: Haelterman, Raquel Mercedes. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFYMA); Argentina.Fil: Rodriguez, Ana Valeria. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Manfredi; ArgentinaFil: Leiva, Rocío. Instituto Superior Albert Sabin; ArgentinaFil: Conci, Luis Rogelio. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFYMA); Argentina.Fil: Alemandri, Vanina Maria. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFYMA); Argentina

Engineering a highly defective stable UiO-66 with tunable Lewis-Brønsted acidity : the role of the hemilabile linker

The stability of metal-organic frameworks (MOFs) typically decreases with an increasing number of defects, limiting the number of defects that can be created and limiting catalytic and other applications. Herein, we use a hemilabile (Hl) linker to create up to a maximum of six defects per cluster in UiO-66. We synthesized hemilabile UiO-66 (Hl-UiO-66) using benzene dicarboxylate (BDC) as linker and 4-sulfonatobenzoate (PSBA) as the hemilabile linker. The PSBA acts not only as a modulator to create defects but also as a coligand that enhances the stability of the resulting defective framework. Furthermore, upon a postsynthetic treatment in H2SO4, the average number of defects increases to the optimum of six missing BDC linkers per cluster (three per formula unit), leaving the Zr-nodes on average sixfold coordinated. Remarkably, the thermal stability of the materials further increases upon this treatment. Periodic density functional theory calculations confirm that the hemilabile ligands strengthen this highly defective structure by several stabilizing interactions. Finally, the catalytic activity of the obtained materials is evaluated in the acid-catalyzed isomerization of a-pinene oxide. This reaction is particularly sensitive to the Bronsted or Lewis acid sites in the catalyst. In comparison to the pristine UiO-66, which mainly possesses Bronsted acid sites, the Hl-UiO-66 and the postsynthetically treated Hl-UiO-66 structures exhibited a higher Lewis acidity and an enhanced activity and selectivity. This is further explored by CD3CN spectroscopic sorption experiments. We have shown that by tuning the number of defects in UiO-66 using PSBA as the hemilabile linker, one can achieve highly defective and stable MOFs and easily control the Bronsted to Lewis acid ratio in the materials and thus their catalytic activity and selectivity

Consolidation of an Olfactory Memory Trace in the Olfactory Bulb Is Required for Learning-Induced Survival of Adult-Born Neurons and Long-Term Memory

Background: It has recently been proposed that adult-born neurons in the olfactory bulb, whose survival is modulated by learning, support long-term olfactory memory. However, the mechanism used to select which adult-born neurons following learning will participate in the long-term retention of olfactory information is unknown. We addressed this question by investigating the effect of bulbar consolidation of olfactory learning on memory and neurogenesis. Methodology/Principal Findings: Initially, we used a behavioral ecological approach using adult mice to assess the impact of consolidation on neurogenesis. Using learning paradigms in which consolidation time was varied, we showed that a spaced (across days), but not a massed (within day), learning paradigm increased survival of adult-born neurons and allowed long-term retention of the task. Subsequently, we used a pharmacological approach to block consolidation in the olfactory bulb, consisting in intrabulbar infusion of the protein synthesis inhibitor anisomycin, and found impaired learning and no increase in neurogenesis, while basic olfactory processing and the basal rate of adult-born neuron survival remained unaffected. Taken together these data indicate that survival of adult-born neurons during learning depends on consolidation processes taking place in the olfactory bulb. Conclusion/Significance: We can thus propose a model in which consolidation processes in the olfactory bulb determine both survival of adult-born neurons and long-term olfactory memory. The finding that adult-born neuron survival durin

A dualistic model of primary anal canal adenocarcinoma with distinct cellular origins, etiologies, inflammatory microenvironments and mutational signatures: implications for personalised medicine.

Primary adenocarcinoma of the anal canal is a rare and aggressive gastrointestinal disease with unclear pathogenesis. Because of its rarity, no clear clinical practice guideline has been defined and a targeted therapeutic armamentarium has yet to be developed. The present article aimed at addressing this information gap by in-depth characterising the anal glandular neoplasms at the histologic, immunologic, genomic and epidemiologic levels. In this multi-institutional study, we first examined the histological features displayed by each collected tumour (n = 74) and analysed their etiological relationship with human papillomavirus (HPV) infection. The intratumoural immune cell subsets (CD4, CD8, Foxp3), the expression of immune checkpoints (PD-1, PD-L1), the defect in mismatch repair proteins and the mutation analysis of multiple clinically relevant genes in the gastrointestinal cancer setting were also determined. Finally, the prognostic significance of each clinicopathological variable was assessed. Phenotypic analysis revealed two region-specific subtypes of anal canal adenocarcinoma. The significant differences in the HPV status, density of tumour-infiltrating lymphocytes, expression of immune checkpoints and mutational profile of several targetable genes further supported the separation of these latter neoplasms into two distinct entities. Importantly, anal gland/transitional-type cancers, which poorly respond to standard treatments, displayed less mutations in downstream effectors of the EGFR signalling pathway (i.e., KRAS and NRAS) and demonstrated a significantly higher expression of the immune inhibitory ligand-receptor pair PD-1/PD-L1 compared to their counterparts arising from the colorectal mucosa. Taken together, the findings reported in the present article reveal, for the first time, that glandular neoplasms of the anal canal arise by HPV-dependent or independent pathways. These etiological differences leads to both individual immune profiles and mutational landscapes that can be targeted for therapeutic benefits