Mauricio Luna - Academia.edu (original) (raw)
Papers by Mauricio Luna
Revista Chapingo Serie Ciencias Forestales y del Ambiente, 2011
El aprovechamiento forestal basado en la extracción de individuos fenotípicamente superiores, al ... more El aprovechamiento forestal basado en la extracción de individuos fenotípicamente superiores, al igual que otros factores, podría hacer degenerar el bosque al dejar árboles de menor calidad y disminuir la diversidad genética. La población de Juglans pyriformis en San José Buenavista, Veracruz (SJB), ha sido reducida por actividades agropecuarias y aprovechamiento forestal con fines maderables bajo el método silvícola de Selección Individual, mientras que la población de Coacoatzintla, Veracruz (COA), se ha reducido por cambios de uso de suelo y explotación clandestina. El objetivo fue determinar los niveles de variación fenotípica de J. pyriformis en SJB y contrastarla con la variación encontrada en la población de COA en un estudio previo, utilizando la misma metodología. En SJB el análisis de componentes principales identificó tres indicadores, FUSTE, COPA y ALT-DIAM, con un coeficiente de variación alto 26, 30 y 42 % respectivamente. El análisis de conglomerados mostró dos grupos de árboles, y el estadístico de Levene fue significativo (P<0.05) para el indicador COPA (0.030) y ALT-DIAM (0.161). Los resultados muestran una menor variación morfológica en la
REVISTA CHAPINGO SERIE CIENCIAS FORESTALES Y DEL AMBIENTE, 2010
La utilización de radiaciones ionizantes ha resultado de utilidad en los trabajos de mejoramiento... more La utilización de radiaciones ionizantes ha resultado de utilidad en los trabajos de mejoramiento genético de especies forestales. Sin embargo, su uso debe estar precedido por ensayos que permitan determinar el efecto que tiene sobre el material vegetal utilizado. Se realizó un experimento con el fin de evaluar el efecto de diversas dosis de radiaciones gamma (2, 5, 10, 15 y 20 Gy) comparado con un control sin irradiación, sobre el porcentaje de germinación de semillas de Abies religiosa (Kunth) Schltd. et Cham. procedentes del Cofre de Perote, Veracruz, México, así como sobre la variable altura y el número de hojas primarias de los propágulos germinados. Al analizar los datos y compararlos con el control se observó que las dosis produjeron un efecto severo en los caracteres evaluados. La germinación varió de 0 a 39, el control fue de 62 %. Las dosis de 5 Gy, clasificadas dentro del grupo I, por análisis de conglomerado, produjeron un efecto beneficioso en el carácter altura de la planta. No obstante, en estudios futuros que se desarrollen de esta especie, es recomendable evaluar el efecto de varias dosis que incluya valores por debajo de 2 Gy hasta 5 Gy.
Cuadernos de Biodiversidad, 2014
Three protocols were developed based on real- time RT-PCR with SYBR Green system and were compare... more Three protocols were developed based on real- time RT-PCR with SYBR Green system and were compared with conventional RT-PCR for detection of the Citrus exocortis viroid (CEVd), Hop stunt viroid (HSVd) and Citrus dwarf viroid (CDVd) using specific primers combinations; additionally, we conducted the analysis of citrus viroids from 90 citrus threes samples collected in orchards in the northeast of Mexico. Evaluated citrus samples comprised different species from the municipalities of General Teran, Montemorelos and Marin, Nuevo Leon, besides Rio Bravo, Victoria city and Hidalgo, Tamaulipas. Total RNA was extracted from the samples and analyzed by the techniques of multiple RT-PCR and real time RT-PCR with the SYBR Green system. We detected CEVd, HSVd and CDVd viroids individually and jointly in the samples. Using real-time RT-PCR with SYBR Green, we found a 41 % of CEVd positive samples, 42 % for HSVd and 49 % to CDVd. Comparing endpoint multiplex RT-PCR with real- time RT-PCR techniq...
Resumen . Se llevo a cabo el aislamiento de cepas productoras de ocratoxinas en cafe pergamino ( ... more Resumen . Se llevo a cabo el aislamiento de cepas productoras de ocratoxinas en cafe pergamino ( Coffea arabica ) almacenado durante siete meses en tres beneficios de una region productora en Mexico. Paralelamente, se determino el contenido de ocratoxina A (OTA) por el metodo de inmunoafinidad. Si bien, los valores iniciales (despues de 2 meses de almacenamiento) fluctuaron entre 1.2 a 7.7 ppb, no aumentaron a niveles no permitidos despues de 5 meses de almacenamiento, debido a que las condiciones naturales de humedad y temperatura, caracteristicas de la region estudiada no favorecieron el desarrollo fungico; no obstante, el 100% de las cepas de Aspergillus niger encontradas mostro posibilidades de producir dichas micotoxinas, si las condiciones de temperatura y humedad no se controlan. Por tal motivo, en el presente trabajo se presenta una metodologia combinada de deteccion de OTA comercial (inmunoafinidad), con la valoracion de la capacidad productora de OTA por cepas nativas de
Se llevo a cabo el aislamiento de cepas productoras de ocratoxinas en cafe pergamino (Coffea arab... more Se llevo a cabo el aislamiento de cepas productoras de ocratoxinas en cafe pergamino (Coffea arabica) almacenado durante siete meses en tres beneficios de una region productora en Mexico. Paralelamente, se determino el contenido de ocratoxina A (OTA) por el metodo de inmunoafinidad. Si bien, los valores iniciales (despues de 2 meses de almacenamiento) fluctuaron entre 1.2 a 7.7 ppb, no aumentaron a niveles no permitidos despues de 5 meses de almacenamiento, debido a que las condiciones naturales de humedad y temperatura, caracteristicas de la region estudiada no favorecieron el desarrollo fungico; no obstante, el 100% de las cepas de Aspergillus niger encontradas mostro posibilidades de producir dichas micotoxinas, si las condiciones de temperatura y humedad no se controlan. Por tal motivo, en el presente trabajo se presenta una metodologia combinada de deteccion de OTA comercial (inmunoafinidad), con la valoracion de la capacidad productora de OTA por cepas nativas de Aspergillus e...
Background: F. oxysporum as a species complex (FOSC) possess the capacity, to specialize into hos... more Background: F. oxysporum as a species complex (FOSC) possess the capacity, to specialize into host-specific pathogens deriving into formae speciales. This with the help of horizontal gene transfer (HGT) between pathogenic and endophytic individuals of FOSC. From these pathogenic forma speciales, F. oxysporum f. sp. vanillae (Fov) is the causal agent of fusarium wilt producing root and stem rot (RSR) positions itself was the main phytosanitary problem in vanilla plantations worldwide. Nonetheless, the origin of this forma specialis and the behavioral genetics dictating the endophytic/pathogenic Fusarium lifestyles are still unknown. To elucidate the underlying molecular mechanisms that establish these behaviors we analyzed the RNA-seq libraries of two-times frames of vanilla-fov interactions. Results: Our analyses identified the sets of transcripts corresponding to Fov pathogenic strain JAGH3 during the two-times frames of the infection as the sets of the transcripts belonging to end...
Plant Pathology
F. R. Flores-de la Rosa , E. De Luna, J. Adame-Garc ıa , L. G. Iglesias-Andreu and M. Luna-Rodr ı... more F. R. Flores-de la Rosa , E. De Luna, J. Adame-Garc ıa , L. G. Iglesias-Andreu and M. Luna-Rodr ıguez* Instituto de Biotecnolog ıa y Ecolog ıa Aplicada, Universidad Veracruzana, Av. de las Culturas Veracruzanas #101 col. Emiliano Zapata, Xalapa, Veracruz, CP, 91090; Red de Biodiversidad y Sistem atica, Instituto de Ecolog ıa AC, Carretera antigua a Coatepec 351, El Haya, Xalapa Enr ıquez, Veracruz, CP, 91070; Tecnol ogico Nacional de M exico, Instituto Tecnol ogico de Ursulo Galv an, Km 4.5 Carretera Cardel-Chachalacas, Ursulo Galv an, Veracruz, CP, 91667; and Laboratorio de Gen etica e Interacciones Planta Microorganismos, Facultad de Ciencias Agr ıcolas, Universidad Veracruzana, Circuito Gonzalo Aguirre Beltr an s/n, Zona Universitaria, Xalapa, Veracruz, CP 91090, Mexico
Environment, Development and Sustainability
Native corn in Mexico can be affected by maize bushy stunt disease (MBS), which can negatively im... more Native corn in Mexico can be affected by maize bushy stunt disease (MBS), which can negatively impact maize-farming operations. Maize bushy stunt symptoms in native corn were linked to the presence of phytoplasmas through molecular analysis of symptomatic native corn plants in Mexico. These findings motivated a socioeconomic characterization and identification of the management strategies developed by the “subsistence farmers” of those communities to answer the questions: What elements of farming affect the presence of MBS disease in “subsistence farmers” fields? What do “subsistence farmers” know about MBS disease and the pathogen associated with MBS disease? How best can MBS disease be managed in small farming communities in Mexico? Through face-to-face interviews with growers and the corresponding analyses of their responses, we identified a widespread lack of knowledge about MBS disease, its causal agent and its vector(s). This study highlighted factors useful to guide future management decisions and education programs, as well as further research to transmit information about MBS disease among “subsistence farmers” in rural communities in Mexico.
Annals of Applied Biology
Phytoplasmas in the X-disease group (16SrIII) are highly diverse in terms of geographic distribut... more Phytoplasmas in the X-disease group (16SrIII) are highly diverse in terms of geographic distributions, vectorship and plant host specificity. Such biological and ecological diversity is often correlated with distinctive genetic markers present in evolutionarily conserved genes. Based on restriction fragment length polymorphism (RFLP) markers in the 16S rRNA gene sequences, 29 subgroups have been delineated, with most of them being found in the Americas. However, it has been unknown whether distinct geographic lineages are present within a given subgroup. Prior to this study, phytoplasmas belonging to subgroups 16SrIII-J and 16SrIII-U were reported only in countries located in South America. In the present study, we identified new phytoplasmas strains closely related to the reference strains of the two subgroups in Mexico, a North American country. These newly identified Mexican strains possess unique RFLP, single nucleotide polymorphism, and fragmental deletion markers in 16S rRNA- and/or ribosomal protein-encoding genes. Since these markers consistently distinguished the Mexican strains from their South American counterparts, they may represent emerging or previously unknown North American geographic lineages of the subgroups 16SrIII-J and 16SrIII-U.
Scientific Reports, 2017
Geographically diverse samples from strawberry exhibiting symptoms of Strawberry Green Petal (SbG... more Geographically diverse samples from strawberry exhibiting symptoms of Strawberry Green Petal (SbGP), periwinkle plants with virescence, and blackberry, blueberry, and raspberry plants displaying yellowing and inedible fruits, were assayed for the presence of phytoplasma DNA. PCR targeting the 16S rRNA-encoding gene and chaperonin-60 (cpn60) showed that the plants were infected with phytoplasma subgroup16SrXIII-(A/I)I (SbGP/MPV). To examine the geographic distribution of this pathogen in Mexico, we designed an array of cpn60-targeted molecular diagnostic assays for SbGP/ MPV phytoplasma. A fluorescent microsphere hybridization assay was designed that was capable of detecting SbGP/MPV phytoplasma in infected plant tissues, successfully differentiating it from other known phytoplasma cpn60 UT sequences, while identifying a double infection with SbGP/MPV and aster yellows (16SrI) phytoplasma. Two quantitative assays, quantitative real-time PCR (qRT-PCR) and droplet digital PCR (ddPCR), gave similar results in infected samples. Finally, a loop-mediated isothermal amplification (LAMP) assay provided rapid detection of SbGP/MPV phytoplasma DNA. Application of these assays revealed that SbGP/MPV phytoplasma is widely distributed in Central Mexico, with positive samples identified from eleven localities within three states separated by hundreds of kilometres. These results also provide tools for determining the presence and geographic distribution of this pathogen in plant and insect samples in other localities. Phytoplasmas ('Candidatus Phytoplasma' spp.) are wall-less bacteria that were first described as mycoplasma-like organisms 1 with a small, AT rich and distinctive genome, that are taxonomically classified as Mollicutes 2, 3. Phytoplasmas are insect-vectored plant pathogens that infect a very wide variety of plants, including most crop species, causing developmental alterations leading to leaf-like floral structures and aborted seed production 4-6. Detection of phytoplasma infection in plant and insect tissues, along with proper classification and identification, is therefore critical for disease surveillance and control 2. However, phytoplasmas are unculturable microorganisms and the detection and classification criteria are based on the use of molecular approaches 7. Phytoplasma detection has relied on PCR amplification of targets within and surrounding the 16 S rRNA-encoding gene 8. Identification and classification has typically used restriction fragment length polymorphism (RFLP) analysis of this locus 9 , resulting in the identification of over thirty 16Sr groups described as16SrI-16SrXXXIII 10. However, other genes have been used as additional markers, including the groEL or cpn60 gene 11, 12. The cpn60 universal target (cpn60 UT), a sequence of approximately 550 bp, is located within the Cpn60-encoding gene 13. This
Tropical Plant Pathology, 2016
Catharantus roseus, known as periwinkle, is highly susceptible to phytoplasma infection. Periwink... more Catharantus roseus, known as periwinkle, is highly susceptible to phytoplasma infection. Periwinkle plants showing proliferation symptoms were detected during 2013–2014 in four geographically distant states in Mexico. The presence of phytoplasmas was confirmed through the amplification of 16S F2nR2 and cpn60 UT sequences from symptomatic plants. Sequencing, phylogenetic analysis and in vitro RFLP revealed that the isolates were ‘Candidatus Phytoplasma asteris’-related strains and members of the 16SrI-B subgroup, confirming the association of this phytoplasma group with periwinkle proliferation disease in Mexico. We also demonstrated that the use of the approximately 550 pb cpn60 universal target sequences allow the differentiation of two 16SrI-B strains, designated here as MePP-Centre, and MePP-South.
Se realizo un estudio para evaluar el grado de variacion morfometrica, isoenzimatica, y molecular... more Se realizo un estudio para evaluar el grado de variacion morfometrica, isoenzimatica, y molecular en una plantacion forestal de Pinus patula Schede ex Schldtl & Cham., en el Estado de Veracruz, Mexico. Los objetivos principales de este estudio fueron la obtencion de criterios sobre la calidad de la plantacion y el establecimiento de una metodologia para la seleccion de fuentes parentales adecuadas para la produccion de semillas de mayor calidad genetica...
Revista Mexicana De Micologia, Dec 1, 2010
Resumen . Se llevo a cabo el aislamiento de cepas productoras de ocratoxinas en cafe pergamino ( ... more Resumen . Se llevo a cabo el aislamiento de cepas productoras de ocratoxinas en cafe pergamino ( Coffea arabica ) almacenado durante siete meses en tres beneficios de una region productora en Mexico. Paralelamente, se determino el contenido de ocratoxina A (OTA) por el metodo de inmunoafinidad. Si bien, los valores iniciales (despues de 2 meses de almacenamiento) fluctuaron entre 1.2 a 7.7 ppb, no aumentaron a niveles no permitidos despues de 5 meses de almacenamiento, debido a que las condiciones naturales de humedad y temperatura, caracteristicas de la region estudiada no favorecieron el desarrollo fungico; no obstante, el 100% de las cepas de Aspergillus niger encontradas mostro posibilidades de producir dichas micotoxinas, si las condiciones de temperatura y humedad no se controlan. Por tal motivo, en el presente trabajo se presenta una metodologia combinada de deteccion de OTA comercial (inmunoafinidad), con la valoracion de la capacidad productora de OTA por cepas nativas de
Revista Colombiana De Biotecnologia, Jul 1, 2011
Botanical Sciences, 2015
Although vanilla originated from Mexico and an important pathogen for this plant is Fusarium oxys... more Although vanilla originated from Mexico and an important pathogen for this plant is Fusarium oxysporum f. sp. vanilla, studies concerning their association are limited. Previous reports on agents that cause root and stem rot in vanilla clearly indicate that Fusarium species are associated with this disease. During 2009 and 2010 in Papantla, which is the greatest vanilla-producing region of Mexico, the fungus was isolated from vanilla roots and stems that showed symptoms of the disease. From 189 isolates of Fusarium, 11 morphologically different colonies were selected to verify the species of each colony by microscopic observation of their morphological characteristics when cultivated on SNA and PDA media and by amplifying and sequencing their ITS regions. The detected species corresponded to F. proliferatum, Fusarium sp., F. oxysporum f. sp. vanillae (which was the most numerous and most pathogenic to vanilla stems and leaves), an undetermined species of Fusarium, and F. proliferatum, which showed no evidence of producing disease symptoms.
International Journal of Systematic and Evolutionary Microbiology, 2015
Phytoplasmas ('Candidatus Phytoplasma') are insect-transmitted, cell-wall-less, plantpathogenic b... more Phytoplasmas ('Candidatus Phytoplasma') are insect-transmitted, cell-wall-less, plantpathogenic bacteria that cause economically important crop diseases. Because phytoplasmas are difficult or impossible to culture in vitro, they are classified taxonomically according to the convention used for unculturable microorganisms. The first coherent scheme of classification of phytoplasmas, based on the RFLP pattern of the 16S rRNA-encoding gene generated with 17 restriction endonucleases, was updated several times until the development of the i PhyClassifier. i PhyClassifier is an interactive online tool capable of determining the species, group and subgroup of 'Candidatus Phytoplasma' of unknown samples using the 16S F2nR2 sequence. Latin America, an important geographical area in relation to food production, has a high incidence of plant diseases caused by phytoplasmas. However, many phytoplasmas associated with these diseases have not been properly classified. An extensive literature review and the use of i PhyClassifier allowed us to identify two new tentative groups (16SrXXXIII-A and 16SrXXXIV-A) and the following tentative new subgroups among Latin American strains that were either previously unclassified or misclassified: six in 16SrI, six in 16SrII, one in 16SrIII, one in 16SrVII, one in 16SrIX, one in 16SrXII and two in 16SrXIII. Details of i PhyClassifier analyses are available with the online Supplementary Material.
Revista Chapingo, Serie Ciencias Forestales y del Ambiente
ABSTRACT
Revista Chapingo Serie Ciencias Forestales y del Ambiente, 2011
El aprovechamiento forestal basado en la extracción de individuos fenotípicamente superiores, al ... more El aprovechamiento forestal basado en la extracción de individuos fenotípicamente superiores, al igual que otros factores, podría hacer degenerar el bosque al dejar árboles de menor calidad y disminuir la diversidad genética. La población de Juglans pyriformis en San José Buenavista, Veracruz (SJB), ha sido reducida por actividades agropecuarias y aprovechamiento forestal con fines maderables bajo el método silvícola de Selección Individual, mientras que la población de Coacoatzintla, Veracruz (COA), se ha reducido por cambios de uso de suelo y explotación clandestina. El objetivo fue determinar los niveles de variación fenotípica de J. pyriformis en SJB y contrastarla con la variación encontrada en la población de COA en un estudio previo, utilizando la misma metodología. En SJB el análisis de componentes principales identificó tres indicadores, FUSTE, COPA y ALT-DIAM, con un coeficiente de variación alto 26, 30 y 42 % respectivamente. El análisis de conglomerados mostró dos grupos de árboles, y el estadístico de Levene fue significativo (P<0.05) para el indicador COPA (0.030) y ALT-DIAM (0.161). Los resultados muestran una menor variación morfológica en la
REVISTA CHAPINGO SERIE CIENCIAS FORESTALES Y DEL AMBIENTE, 2010
La utilización de radiaciones ionizantes ha resultado de utilidad en los trabajos de mejoramiento... more La utilización de radiaciones ionizantes ha resultado de utilidad en los trabajos de mejoramiento genético de especies forestales. Sin embargo, su uso debe estar precedido por ensayos que permitan determinar el efecto que tiene sobre el material vegetal utilizado. Se realizó un experimento con el fin de evaluar el efecto de diversas dosis de radiaciones gamma (2, 5, 10, 15 y 20 Gy) comparado con un control sin irradiación, sobre el porcentaje de germinación de semillas de Abies religiosa (Kunth) Schltd. et Cham. procedentes del Cofre de Perote, Veracruz, México, así como sobre la variable altura y el número de hojas primarias de los propágulos germinados. Al analizar los datos y compararlos con el control se observó que las dosis produjeron un efecto severo en los caracteres evaluados. La germinación varió de 0 a 39, el control fue de 62 %. Las dosis de 5 Gy, clasificadas dentro del grupo I, por análisis de conglomerado, produjeron un efecto beneficioso en el carácter altura de la planta. No obstante, en estudios futuros que se desarrollen de esta especie, es recomendable evaluar el efecto de varias dosis que incluya valores por debajo de 2 Gy hasta 5 Gy.
Cuadernos de Biodiversidad, 2014
Three protocols were developed based on real- time RT-PCR with SYBR Green system and were compare... more Three protocols were developed based on real- time RT-PCR with SYBR Green system and were compared with conventional RT-PCR for detection of the Citrus exocortis viroid (CEVd), Hop stunt viroid (HSVd) and Citrus dwarf viroid (CDVd) using specific primers combinations; additionally, we conducted the analysis of citrus viroids from 90 citrus threes samples collected in orchards in the northeast of Mexico. Evaluated citrus samples comprised different species from the municipalities of General Teran, Montemorelos and Marin, Nuevo Leon, besides Rio Bravo, Victoria city and Hidalgo, Tamaulipas. Total RNA was extracted from the samples and analyzed by the techniques of multiple RT-PCR and real time RT-PCR with the SYBR Green system. We detected CEVd, HSVd and CDVd viroids individually and jointly in the samples. Using real-time RT-PCR with SYBR Green, we found a 41 % of CEVd positive samples, 42 % for HSVd and 49 % to CDVd. Comparing endpoint multiplex RT-PCR with real- time RT-PCR techniq...
Resumen . Se llevo a cabo el aislamiento de cepas productoras de ocratoxinas en cafe pergamino ( ... more Resumen . Se llevo a cabo el aislamiento de cepas productoras de ocratoxinas en cafe pergamino ( Coffea arabica ) almacenado durante siete meses en tres beneficios de una region productora en Mexico. Paralelamente, se determino el contenido de ocratoxina A (OTA) por el metodo de inmunoafinidad. Si bien, los valores iniciales (despues de 2 meses de almacenamiento) fluctuaron entre 1.2 a 7.7 ppb, no aumentaron a niveles no permitidos despues de 5 meses de almacenamiento, debido a que las condiciones naturales de humedad y temperatura, caracteristicas de la region estudiada no favorecieron el desarrollo fungico; no obstante, el 100% de las cepas de Aspergillus niger encontradas mostro posibilidades de producir dichas micotoxinas, si las condiciones de temperatura y humedad no se controlan. Por tal motivo, en el presente trabajo se presenta una metodologia combinada de deteccion de OTA comercial (inmunoafinidad), con la valoracion de la capacidad productora de OTA por cepas nativas de
Se llevo a cabo el aislamiento de cepas productoras de ocratoxinas en cafe pergamino (Coffea arab... more Se llevo a cabo el aislamiento de cepas productoras de ocratoxinas en cafe pergamino (Coffea arabica) almacenado durante siete meses en tres beneficios de una region productora en Mexico. Paralelamente, se determino el contenido de ocratoxina A (OTA) por el metodo de inmunoafinidad. Si bien, los valores iniciales (despues de 2 meses de almacenamiento) fluctuaron entre 1.2 a 7.7 ppb, no aumentaron a niveles no permitidos despues de 5 meses de almacenamiento, debido a que las condiciones naturales de humedad y temperatura, caracteristicas de la region estudiada no favorecieron el desarrollo fungico; no obstante, el 100% de las cepas de Aspergillus niger encontradas mostro posibilidades de producir dichas micotoxinas, si las condiciones de temperatura y humedad no se controlan. Por tal motivo, en el presente trabajo se presenta una metodologia combinada de deteccion de OTA comercial (inmunoafinidad), con la valoracion de la capacidad productora de OTA por cepas nativas de Aspergillus e...
Background: F. oxysporum as a species complex (FOSC) possess the capacity, to specialize into hos... more Background: F. oxysporum as a species complex (FOSC) possess the capacity, to specialize into host-specific pathogens deriving into formae speciales. This with the help of horizontal gene transfer (HGT) between pathogenic and endophytic individuals of FOSC. From these pathogenic forma speciales, F. oxysporum f. sp. vanillae (Fov) is the causal agent of fusarium wilt producing root and stem rot (RSR) positions itself was the main phytosanitary problem in vanilla plantations worldwide. Nonetheless, the origin of this forma specialis and the behavioral genetics dictating the endophytic/pathogenic Fusarium lifestyles are still unknown. To elucidate the underlying molecular mechanisms that establish these behaviors we analyzed the RNA-seq libraries of two-times frames of vanilla-fov interactions. Results: Our analyses identified the sets of transcripts corresponding to Fov pathogenic strain JAGH3 during the two-times frames of the infection as the sets of the transcripts belonging to end...
Plant Pathology
F. R. Flores-de la Rosa , E. De Luna, J. Adame-Garc ıa , L. G. Iglesias-Andreu and M. Luna-Rodr ı... more F. R. Flores-de la Rosa , E. De Luna, J. Adame-Garc ıa , L. G. Iglesias-Andreu and M. Luna-Rodr ıguez* Instituto de Biotecnolog ıa y Ecolog ıa Aplicada, Universidad Veracruzana, Av. de las Culturas Veracruzanas #101 col. Emiliano Zapata, Xalapa, Veracruz, CP, 91090; Red de Biodiversidad y Sistem atica, Instituto de Ecolog ıa AC, Carretera antigua a Coatepec 351, El Haya, Xalapa Enr ıquez, Veracruz, CP, 91070; Tecnol ogico Nacional de M exico, Instituto Tecnol ogico de Ursulo Galv an, Km 4.5 Carretera Cardel-Chachalacas, Ursulo Galv an, Veracruz, CP, 91667; and Laboratorio de Gen etica e Interacciones Planta Microorganismos, Facultad de Ciencias Agr ıcolas, Universidad Veracruzana, Circuito Gonzalo Aguirre Beltr an s/n, Zona Universitaria, Xalapa, Veracruz, CP 91090, Mexico
Environment, Development and Sustainability
Native corn in Mexico can be affected by maize bushy stunt disease (MBS), which can negatively im... more Native corn in Mexico can be affected by maize bushy stunt disease (MBS), which can negatively impact maize-farming operations. Maize bushy stunt symptoms in native corn were linked to the presence of phytoplasmas through molecular analysis of symptomatic native corn plants in Mexico. These findings motivated a socioeconomic characterization and identification of the management strategies developed by the “subsistence farmers” of those communities to answer the questions: What elements of farming affect the presence of MBS disease in “subsistence farmers” fields? What do “subsistence farmers” know about MBS disease and the pathogen associated with MBS disease? How best can MBS disease be managed in small farming communities in Mexico? Through face-to-face interviews with growers and the corresponding analyses of their responses, we identified a widespread lack of knowledge about MBS disease, its causal agent and its vector(s). This study highlighted factors useful to guide future management decisions and education programs, as well as further research to transmit information about MBS disease among “subsistence farmers” in rural communities in Mexico.
Annals of Applied Biology
Phytoplasmas in the X-disease group (16SrIII) are highly diverse in terms of geographic distribut... more Phytoplasmas in the X-disease group (16SrIII) are highly diverse in terms of geographic distributions, vectorship and plant host specificity. Such biological and ecological diversity is often correlated with distinctive genetic markers present in evolutionarily conserved genes. Based on restriction fragment length polymorphism (RFLP) markers in the 16S rRNA gene sequences, 29 subgroups have been delineated, with most of them being found in the Americas. However, it has been unknown whether distinct geographic lineages are present within a given subgroup. Prior to this study, phytoplasmas belonging to subgroups 16SrIII-J and 16SrIII-U were reported only in countries located in South America. In the present study, we identified new phytoplasmas strains closely related to the reference strains of the two subgroups in Mexico, a North American country. These newly identified Mexican strains possess unique RFLP, single nucleotide polymorphism, and fragmental deletion markers in 16S rRNA- and/or ribosomal protein-encoding genes. Since these markers consistently distinguished the Mexican strains from their South American counterparts, they may represent emerging or previously unknown North American geographic lineages of the subgroups 16SrIII-J and 16SrIII-U.
Scientific Reports, 2017
Geographically diverse samples from strawberry exhibiting symptoms of Strawberry Green Petal (SbG... more Geographically diverse samples from strawberry exhibiting symptoms of Strawberry Green Petal (SbGP), periwinkle plants with virescence, and blackberry, blueberry, and raspberry plants displaying yellowing and inedible fruits, were assayed for the presence of phytoplasma DNA. PCR targeting the 16S rRNA-encoding gene and chaperonin-60 (cpn60) showed that the plants were infected with phytoplasma subgroup16SrXIII-(A/I)I (SbGP/MPV). To examine the geographic distribution of this pathogen in Mexico, we designed an array of cpn60-targeted molecular diagnostic assays for SbGP/ MPV phytoplasma. A fluorescent microsphere hybridization assay was designed that was capable of detecting SbGP/MPV phytoplasma in infected plant tissues, successfully differentiating it from other known phytoplasma cpn60 UT sequences, while identifying a double infection with SbGP/MPV and aster yellows (16SrI) phytoplasma. Two quantitative assays, quantitative real-time PCR (qRT-PCR) and droplet digital PCR (ddPCR), gave similar results in infected samples. Finally, a loop-mediated isothermal amplification (LAMP) assay provided rapid detection of SbGP/MPV phytoplasma DNA. Application of these assays revealed that SbGP/MPV phytoplasma is widely distributed in Central Mexico, with positive samples identified from eleven localities within three states separated by hundreds of kilometres. These results also provide tools for determining the presence and geographic distribution of this pathogen in plant and insect samples in other localities. Phytoplasmas ('Candidatus Phytoplasma' spp.) are wall-less bacteria that were first described as mycoplasma-like organisms 1 with a small, AT rich and distinctive genome, that are taxonomically classified as Mollicutes 2, 3. Phytoplasmas are insect-vectored plant pathogens that infect a very wide variety of plants, including most crop species, causing developmental alterations leading to leaf-like floral structures and aborted seed production 4-6. Detection of phytoplasma infection in plant and insect tissues, along with proper classification and identification, is therefore critical for disease surveillance and control 2. However, phytoplasmas are unculturable microorganisms and the detection and classification criteria are based on the use of molecular approaches 7. Phytoplasma detection has relied on PCR amplification of targets within and surrounding the 16 S rRNA-encoding gene 8. Identification and classification has typically used restriction fragment length polymorphism (RFLP) analysis of this locus 9 , resulting in the identification of over thirty 16Sr groups described as16SrI-16SrXXXIII 10. However, other genes have been used as additional markers, including the groEL or cpn60 gene 11, 12. The cpn60 universal target (cpn60 UT), a sequence of approximately 550 bp, is located within the Cpn60-encoding gene 13. This
Tropical Plant Pathology, 2016
Catharantus roseus, known as periwinkle, is highly susceptible to phytoplasma infection. Periwink... more Catharantus roseus, known as periwinkle, is highly susceptible to phytoplasma infection. Periwinkle plants showing proliferation symptoms were detected during 2013–2014 in four geographically distant states in Mexico. The presence of phytoplasmas was confirmed through the amplification of 16S F2nR2 and cpn60 UT sequences from symptomatic plants. Sequencing, phylogenetic analysis and in vitro RFLP revealed that the isolates were ‘Candidatus Phytoplasma asteris’-related strains and members of the 16SrI-B subgroup, confirming the association of this phytoplasma group with periwinkle proliferation disease in Mexico. We also demonstrated that the use of the approximately 550 pb cpn60 universal target sequences allow the differentiation of two 16SrI-B strains, designated here as MePP-Centre, and MePP-South.
Se realizo un estudio para evaluar el grado de variacion morfometrica, isoenzimatica, y molecular... more Se realizo un estudio para evaluar el grado de variacion morfometrica, isoenzimatica, y molecular en una plantacion forestal de Pinus patula Schede ex Schldtl & Cham., en el Estado de Veracruz, Mexico. Los objetivos principales de este estudio fueron la obtencion de criterios sobre la calidad de la plantacion y el establecimiento de una metodologia para la seleccion de fuentes parentales adecuadas para la produccion de semillas de mayor calidad genetica...
Revista Mexicana De Micologia, Dec 1, 2010
Resumen . Se llevo a cabo el aislamiento de cepas productoras de ocratoxinas en cafe pergamino ( ... more Resumen . Se llevo a cabo el aislamiento de cepas productoras de ocratoxinas en cafe pergamino ( Coffea arabica ) almacenado durante siete meses en tres beneficios de una region productora en Mexico. Paralelamente, se determino el contenido de ocratoxina A (OTA) por el metodo de inmunoafinidad. Si bien, los valores iniciales (despues de 2 meses de almacenamiento) fluctuaron entre 1.2 a 7.7 ppb, no aumentaron a niveles no permitidos despues de 5 meses de almacenamiento, debido a que las condiciones naturales de humedad y temperatura, caracteristicas de la region estudiada no favorecieron el desarrollo fungico; no obstante, el 100% de las cepas de Aspergillus niger encontradas mostro posibilidades de producir dichas micotoxinas, si las condiciones de temperatura y humedad no se controlan. Por tal motivo, en el presente trabajo se presenta una metodologia combinada de deteccion de OTA comercial (inmunoafinidad), con la valoracion de la capacidad productora de OTA por cepas nativas de
Revista Colombiana De Biotecnologia, Jul 1, 2011
Botanical Sciences, 2015
Although vanilla originated from Mexico and an important pathogen for this plant is Fusarium oxys... more Although vanilla originated from Mexico and an important pathogen for this plant is Fusarium oxysporum f. sp. vanilla, studies concerning their association are limited. Previous reports on agents that cause root and stem rot in vanilla clearly indicate that Fusarium species are associated with this disease. During 2009 and 2010 in Papantla, which is the greatest vanilla-producing region of Mexico, the fungus was isolated from vanilla roots and stems that showed symptoms of the disease. From 189 isolates of Fusarium, 11 morphologically different colonies were selected to verify the species of each colony by microscopic observation of their morphological characteristics when cultivated on SNA and PDA media and by amplifying and sequencing their ITS regions. The detected species corresponded to F. proliferatum, Fusarium sp., F. oxysporum f. sp. vanillae (which was the most numerous and most pathogenic to vanilla stems and leaves), an undetermined species of Fusarium, and F. proliferatum, which showed no evidence of producing disease symptoms.
International Journal of Systematic and Evolutionary Microbiology, 2015
Phytoplasmas ('Candidatus Phytoplasma') are insect-transmitted, cell-wall-less, plantpathogenic b... more Phytoplasmas ('Candidatus Phytoplasma') are insect-transmitted, cell-wall-less, plantpathogenic bacteria that cause economically important crop diseases. Because phytoplasmas are difficult or impossible to culture in vitro, they are classified taxonomically according to the convention used for unculturable microorganisms. The first coherent scheme of classification of phytoplasmas, based on the RFLP pattern of the 16S rRNA-encoding gene generated with 17 restriction endonucleases, was updated several times until the development of the i PhyClassifier. i PhyClassifier is an interactive online tool capable of determining the species, group and subgroup of 'Candidatus Phytoplasma' of unknown samples using the 16S F2nR2 sequence. Latin America, an important geographical area in relation to food production, has a high incidence of plant diseases caused by phytoplasmas. However, many phytoplasmas associated with these diseases have not been properly classified. An extensive literature review and the use of i PhyClassifier allowed us to identify two new tentative groups (16SrXXXIII-A and 16SrXXXIV-A) and the following tentative new subgroups among Latin American strains that were either previously unclassified or misclassified: six in 16SrI, six in 16SrII, one in 16SrIII, one in 16SrVII, one in 16SrIX, one in 16SrXII and two in 16SrXIII. Details of i PhyClassifier analyses are available with the online Supplementary Material.
Revista Chapingo, Serie Ciencias Forestales y del Ambiente
ABSTRACT