Variabilidad en cepas de Xylella fastidiosa procedentes de olivo (Olea europaea L.) de Argentina [resumen]

Xylella fastidiosa, es considerada una bacteria polífaga, capaz de vivir y multiplicarse en un amplio rango de hospedantes, más de 500 especies de plantas, abarcando tanto cultivos de interés agrícola como especies ornamentales y malezas. En el año 2013, se dieron las primeras detecciones de la bacteria en fincas tradicionales de olivo de La Rioja, observando un marcado declinamiento en las plantas, hasta causar la muerte de ejemplares de más de 50 años de edad. Posteriormente, fue reportada en plantaciones de las provincias de Córdoba y Catamarca. X. fastidiosa es una bacteria genéticamente diversa que actualmente comprende las siguientes subespecies: fastidiosa, pauca, multiplex, sandyi, morus y tashke. Mediante el sistema de clasificación Multilocus Sequence Typing (MLST), se caracterizaron aislamientos de la bacteria proveniente de olivo de las provincias de La Rioja, Córdoba y Catamarca, obteniéndose la misma secuencia tipo-ST69Instituto de Patología VegetalFil: 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).Córdoba; Argentina.Fil: Olivares García, C. Consejo Superior de Investigaciones Agrícolas. Instituto de Agricultura Sostenible; EspañaFil: Guzman, Fabiana. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Manfredi. Agencia De Extensión Rural Villa Dolores. Villa Dolores, Córdoba; ArgentinaFil:Landa Del Castillo, B.B. Consejo Superior de Investigaciones Agrícolas. Instituto de Agricultura Sostenible; EspañaFil: 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

Tritordeum breads are well tolerated with preference over gluten-free breads in non-celiac wheat-sensitive patients and its consumption induce changes in gut bacteria

BACKGROUND The ingestion of wheat and other cereals are related to several gut disorders. The specific components responsible for non-celiac wheat-sensitivity (NCWS) may include gluten and other compounds. Tritordeum is a new cereal derived from crossing durum wheat with a wild barley species, which differs from bread wheat in its gluten composition. In the present work, we examined the response of NCWS patients to tritordeum bread Gastrointestinal symptoms as well as tritordeum acceptability, gluten immunogenic peptides excretion, and the composition and structure of the intestinal microbiota were evaluated. RESULTS Gastrointestinal symptoms of the subjects showed no significant change between the gluten-free bread and the tritordeum bread. Participating subjects rated tritordeum bread higher than the gluten-free bread. Analysis of the bacterial gut microbiota indicated that tritordeum consumption does not alter the global structure and composition of the intestinal microbiota, and only a few changes in some butyrate-producing bacteria were observed. CONCLUSIONS All the results derived from acceptability, biochemical and microbiological tests suggest that tritordeum may be tolerated by a sub-set of NCWS sufferers who do not require strict exclusion of gluten from their diet. (c) 2020 Society of Chemical Industry

Aplicaciones de metodologías moleculares y biotecnológicas en la investigación sobre las enfermedades de cultivos en la Agricultura Sostenible

Las enfermedades son un componente de significación en la producción agrícola actual porque pueden reducir el rendimiento potencial o causar devastación en los cultivos de plantas; y la extensión y severidad de sus ataques va unida a los cambios que se están produciendo en los sistemas de manejo que dan lugar a mejoras en el rendimiento o modificaciones en los ambientes de producción. El control eficiente de las enfermedades requiere necesariamente la determinación exacta, rápida e informativa de su etiología, incluyendo la evaluación de la historia y potencial evolutivo en las poblaciones del agente causal, así como de la composición y diversidad de la microbiota beneficiosa asociada con el crecimiento vegetal, que hagan posible la aplicación eficiente de las acciones de prevención en que se fundamenta el manejo sostenible de dichas enfermedades. Las tecnologías de base molecular y biotecnológica ofrecen una excelente oportunidad para mejorar nuestras capacidades para satisfacer dichos requisitos. En este trabajo se ilustran tales oportunidades utilizando como ejemplo los resultados alcanzados por el Grupo AGR136 ‘Sanidad Vegetal’ durante el desarrollo de programa de investigación llevados a cabo sobre enfermedades importantes en la agricultura andaluz

Avances en teledetección para la prevención y detección temprana de Xylella fastidiosa en el marco de los proyectos H2020 POnTE y XF-ACTORS.

Informational article of the tasks carried out in WP6 of POnTE and WP3 of XF-ACTORS in a professional Spanish magazin

Antagonistic activity of bacteria from the chickpea rhizosphere against Fusarium oxysporum f.sp. ciceris.

The antagonistic activity against in vitro growth of Fusarium oxysporum f.sp. ciceris was determined for 74 bacterial isolates obtained from the rhizosphere of chickpeas grown in two field soils with different histories of Fusarium wilt, and for seven isolates of Pseudomonas spp. from culture collections. Twenty-four isolates of Bacillus spp. and Pseudomonas chlororaphis 30-84 showed a strong antagonism against three races (0, 1 and 5) of F.o. ciceris tested. Three selected Bacillus isolates and P. chlororaphis 30-84 were further tested against 30 isolates of races 0, 1 and 5 of F.o ciceris, races 0,1 and 2 of F.o. melonis, F.o. Phaseoli and nonpathogenic F. oxysporum. Bacillus isolates differed in their antagonistic activity and were less inhibitory to myce lial growth of F.o. ciceris than to that of other fungal isolates. Furthermore, the extent of growth inhibition of F.o. ciceris was influenced both by bacterial isolates and by race of the pathogen. Cell-free culture filtrates of four Bacillus isolates inhibited conidial germination and hyphal growth of F.o. ciceris and nonpathogenic F. oxysporum. Joint seed+soil treatment with some selected antagonistic Bacillus spp. isolates suppressed disease caused by the highly virulent F.o. ciceris race-5 in cv. ICCV 4 and cv. PV 61 chickpeas. However, the degree of protection was influenced by the host genotype and the inoculum concentration of pathogen

Antagonistic activity of bacteria from the chickpea rhizosphere against Fusarium oxysporum f.sp. ciceris.

The antagonistic activity against in vitro growth of Fusarium oxysporum f.sp. ciceris was determined for 74 bacterial isolates obtained from the rhizosphere of chickpeas grown in two field soils with different histories of Fusarium wilt, and for seven isolates of Pseudomonas spp. from culture collections. Twenty-four isolates of Bacillus spp. and Pseudomonas chlororaphis 30-84 showed a strong antagonism against three races (0, 1 and 5) of F.o. ciceris tested. Three selected Bacillus isolates and P. chlororaphis 30-84 were further tested against 30 isolates of races 0, 1 and 5 of F.o ciceris, races 0,1 and 2 of F.o. melonis, F.o. Phaseoli and nonpathogenic F. oxysporum. Bacillus isolates differed in their antagonistic activity and were less inhibitory to myce lial growth of F.o. ciceris than to that of other fungal isolates. Furthermore, the extent of growth inhibition of F.o. ciceris was influenced both by bacterial isolates and by race of the pathogen. Cell-free culture filtrates of four Bacillus isolates inhibited conidial germination and hyphal growth of F.o. ciceris and nonpathogenic F. oxysporum. Joint seed+soil treatment with some selected antagonistic Bacillus spp. isolates suppressed disease caused by the highly virulent F.o. ciceris race-5 in cv. ICCV 4 and cv. PV 61 chickpeas. However, the degree of protection was influenced by the host genotype and the inoculum concentration of pathogen.Made available in DSpace on 2017-01-16T23:00:39Z (GMT). No. of bitstreams: 1 1997AP039BettiolAntagonistic3360.PDF: 309959 bytes, checksum: 99c0e62f6c5f75f76add61f34efa32a1 (MD5) Previous issue date: 1998-03-05199

Effect of fusaric acid and phytoanticipins on growth of rhizobacteria and Fusarium oxysporum

International audienc

Characterization of the Cystoid Nematode Meloidoderita kirjanovae (Nemata: Sphaeronematidae) from Southern Italy

A population of the cystoid nematode Meloidoderita kirjanovae was detected parasitizing water mint (Mentha aquatica) in southern Italy. The morphological identification of this species was confirmed by molecular analysis using the internal transcribed spacer 1 (ITS1) and 5.8S gene sequences of nuclear ribosomal DNA (rDNA), which clearly separated it from the closely related species Meloidoderita polygoni. A phylogenetic analysis of M. kirjanovae with species of related genera was conducted using sequences of the D2-D3 expansion segments of the 28S nuclear ribosomal RNA gene. The resulting phylogenetic tree was congruent with trees from an extended dataset for Criconematina and Tylenchida. The basal position of the genus Meloidoderita together with Sphaeronema within the Criconematina clade in this tree may indicate their close relationships. The anatomical changes induced by M. kirjanovae population from Italy in water mint were similar to those reported for a nematode population infecting roots of M. longifolia in Israel. Nematode feeding caused the formation of a stellar syncytium that disorganized the pericycle and vascular root tissues

A comparison of real-time PCR protocols for the quantitative monitoring of asymptomatic olive infections by Verticillium dahliae pathotypes

Early, specific, and accurate in planta detection and quantification of Verticillium dahliae are essential to prevent the spread of Verticillium wilt in olive using certified pathogen-free planting material and development of resistance. We comparatively assessed the accuracy, specificity, and efficiency of eight real-time quantitative polymerase chain reaction protocols published since 2002 for the specific detection and quantification of V. dahliae in various host plant species and in soil, using a background of DNAs extracted from olive roots, stems, and leaves. Results showed that some of those protocols were not specific for V. dahliae or were inhibited when using backgrounds other than water. Ranking of protocols according to a weighted score system placed protocols TAQ (based on intergenic spacer ribosomal DNA target gene) and SYBR-4 (based on the -tubulin 2 target gene) first in sensitivity and efficiency for the quantification of V. dahliae DNA in small amounts and different types of olive tissues (root and stem) tested. Use of TAQ and SYBR-4 protocols allowed accurate quantification of V. dahliae DNA regardless of the background DNA, with a detection limit being fixed at a cycle threshold of 36 (18 fg for SYBR-4 and 15 fg for TAQ) of V. dahliae. The amount of DNA from defoliating (D) and nondefoliating (ND) V. dahliae pathotypes was monitored in Verticillium wilt-resistant 'Frantoio' olive using the TAQ and SYBR-4 protocols. In the infection bioassay, higher amounts of D V. dahliae DNA were measured in olive stems, whereas the average amount of fungal DNA in roots was higher for ND-infected plants than D-infected ones. Overall, V. dahliae DNA amounts in all olive tissues tested tended to slightly decrease or remain stable by the end of the experiment (35 days after inoculation). The SYBR-4 and TAQ protocols further enabled detection of V. dahliae in tissues of symptomless plants, suggesting that both techniques can be useful for implementing certification schemes of pathogen-free planting material as well as helpful tools in breeding resistance to V. dahliae in olive. © 2013 The American Phytopathological Society

Tritordeum breads are well tolerated with preference over gluten‐free

BACKGROUND The ingestion of wheat and other cereals are related to several gut disorders. The specific components responsible for non-celiac wheat-sensitivity (NCWS) may include gluten and other compounds. Tritordeum is a new cereal derived from crossing durum wheat with a wild barley species, which differs from bread wheat in its gluten composition. In the present work, we examined the response of NCWS patients to tritordeum bread Gastrointestinal symptoms as well as tritordeum acceptability, gluten immunogenic peptides excretion, and the composition and structure of the intestinal microbiota were evaluated. RESULTS Gastrointestinal symptoms of the subjects showed no significant change between the gluten-free bread and the tritordeum bread. Participating subjects rated tritordeum bread higher than the gluten-free bread. Analysis of the bacterial gut microbiota indicated that tritordeum consumption does not alter the global structure and composition of the intestinal microbiota, and only a few changes in some butyrate-producing bacteria were observed. CONCLUSIONS All the results derived from acceptability, biochemical and microbiological tests suggest that tritordeum may be tolerated by a sub-set of NCWS sufferers who do not require strict exclusion of gluten from their diet. (c) 2020 Society of Chemical Industry