Caracterización molecular, efecto sobre el huésped, y transmisión, del micovirus Fusarium oxysporum f. sp. dianthi virus 1 (FodV1)

Los micovirus son virus que se encuentran infectando a hongos. Estas infecciones víricas afectan a la mayoría de los grupos taxonómicos de hongos, incluyendo los hongos patógenos de plantas. La característica más señalada de los micovirus es que carecen de una ruta extracelular de infección, y solo se transmiten intracelularmente mediante anastomosis hifal (transmisión horizontal) o durante la esporogénesis (transmisión vertical). Usualmente, las infecciones por micovirus son asintomáticas, pero en algunos casos la infección viral se ha asociado a la alteración de determinados caracteres fenotípicos en sus hongos hospedadores. Particularmente interesantes son los micovirus que inducen hipovirulencia en especies fitopatógenas, es decir, que reducen la virulencia del hongo frente a su planta huésped, debido a la posibilidad de ser utilizados como agentes de control biológico de las enfermedades causadas por sus hongos hospedadores. Todos los micovirus asociados a hipovirulencia tienen genomas de RNA de cadena sencilla (ssRNA) o de cadena doble (dsRNA), e incluyen representantes de las familias Totiviridae, Chrysoviridae, Hypoviridae, Narnaviridae y Reoviridae. En este trabajo se describe la estructura genómica completa, el efecto sobre el fenotipo del aislado hospedador, y la transmisión, del micovirus Fusarium oxysporum f. sp. dianthi virus 1 (FodV1), un nuevo miembro de la familia Chrysoviridae identificado en el aislado Fod 116 de Fusarium oxysporum f. sp. dianthi. FodV1 consta de 4 segmentos de dsRNA de 3.555pb (dsRNA1), 2.809 pb (dsRNA2), 2.794 pb (dsRNA3), y 2.646 pb (dsRNA4). DsRNA1 y dsRNA3 codifican una ARN polimerasa dependiente de ARN y una proteina de la cápsida, respectivamente; dsRNA2 y dsRNA4 codifican proteínas hipotéticas de función desconocida. El análisis filogenético basado en las secuencias aminoacídicas sitúa a FodV1 en la familia Chrysoviridae, dentro del grupo de los que han sido denominados como “chriso-like” micovirus, todos ellos asociados a la inducción de alteraciones fenotípicas en sus hongos hospedadores. El efecto de FodV1 sobre el fenotipo del hongo se ha determinado utilizando dos versiones del aislado portador Fod 116: una con título elevado del virus (la versión original, Fod 116V+), y otra con niveles residuales de infección viral, obtenida mediante selección y análisis de conidias (Fod 116V-). El análisis comparado de ambas versiones ha puesto de manifiesto un efecto significativo del micovirus FodV1 sobre todos los caracteres fenotípicos analizados. La presencia de títulos altos de FodV1 en el aislado Fod 116 altera la morfología y reduce la velocidad de crecimiento radial en medio sólido, disminuye la tasa de conidiación en medio líquido, y reduce la virulencia sobre clavel del aislado fúngico. Todos estos resultados identifican a FodV1 como un nuevo micovirus inductor de hipovirulencia, con potencial para ser utilizado como agente de control biológico. El éxito en la utilización de micovirus para controlar poblaciones de hongos fitopatógenos depende de la capacidad del micovirus para acumularse de manera estable en su hospedador fúngico, así como de su eficiencia para transmitirse entre aislados y dispersarse en las poblaciones fúngicas naturales. FodV1 presenta un elevado nivel de acumulación en su aislado portador original. Nuestros resultados demuestran que este nivel de acumulación permanece estable a lo largo del tiempo, tras sucesivos subcultivos, o después del paso por planta. Por otra parte, también ha quedado demostrado que FodV1 puede transferirse mediante anastomosis hifal entre aislados vegetativamente compatibles. Para evidenciar dicha transferencia se ha utilizado el aislado originalmente infectado (Fod 116V+, donante) y otro aislado compatible libre de virus y marcado con un gen de resistencia a higromicina (Fod 77HgR, receptor). Los resultados evidencian que el virus no solo se transfiere al aislado receptor, sino que además se acumula en éste a niveles inusualmente altos, similares a los detectados en el aislado donante. El análisis comparado de los aislados Fod 77HgR (libre de virus) y Fod 77HgRV+ (infectado con el virus) ha puesto de manifiesto que FodV1 induce en el nuevo aislado hospedador las mismas alteraciones fenotípicas identificadas en el aislado originalmente infectado. La otra vía de diseminación de la infección viral es a través de las esporas asexuales, o transmisión vertical. En esta tesis se ha analizado la eficiencia en la transmisión vertical de los dos aislados infectados con FodV1, Fod 166V+ y Fod 77HgRV+. Los resultados muestran que dicha eficiencia varía dependiendo del aislado considerado. FodV1 es el primer micovirus asociado a hipovirulencia identificado en la especie F. oxysporum.Fungal viruses (micoviruses) are viruses that infect fungi. Micoviruses are widespread throughout the major taxonomic groups of fungi, including plant-pathogenic species. They lack extracellular routes of transmission and are transmitted intracellularly by hyphal anastomosis (horizontal transmission) and during sporogenesis (vertical transmission). Frequently, mycovirus infections are cryptic, i.e. no discernible phenotypic effects are observed in their hosts, but in some cases the viral infection has been associated with the alteration of particular phenotypic traits in its fungal host. The most interesting cases are those of mycoviruses that induce hypovirulence in phytopathogenic species, that is, that reduce the virulence of the fungus against its host plant, because the possibility of using them as biological control agents of the diseases caused by their fungal hosts. Mycoviruses that induce hypovirulence have all single-stranded (ss) or double-stranded (ds) RNA genomes, and include representatives of the families Totiviridae, Chrysoviridae, Hypoviridae, Narnaviridae and Reoviridae. In this study we describe the complete genomic structure, the effect on the fungal phenotype, and the transmission, of mycovirus Fusarium oxysporum f. sp. dianthi virus 1 (FodV1), a new member of the family Chrysoviridae identified in isolate Fod 116 of Fusarium oxysporum f. sp. dianthi. FodV1 consists of four dsRNA segments of 3,555 bp (dsRNA1), 2,809 bp (dsRNA2), 2,794 bp (dsRNA3), and 2,646 pb (dsRNA4), respectively. DsRNA1 and dsRNA3 encode a RNA-dependent RNA polymerase and a coat protein, respectively; dsRNA2 and dsRNA4 encode hypothetical proteins with unknown functions. Phylogenetic analysis using aminoacid sequences places FodV1 in the Chrysoviridae family, very close to the designated as “chryso-like” mycoviruses, all of them associated to the alteration of phenotypic traits in their hosts. The effect of FodV1 on the phenotype of the fungus has been analysed using two versions of isolate Fod 116: the original one infected with a very high titer of the virus (Fod 116V+), and another one with a very low titer obtained by single conidia selection (Fod 116V-). Comparative analysis of both versions evidences a significative effect of FodV1 on all the phenotypic traits analyzed. Presence of a high titer of FodV1 in isolate Fod 116 alters the morphology and reduces the radial growth of the colony on solid medium, diminishes the conidiation in liquid medium, and reduces the virulence against carnation of its fungal host. All these results place FodV1 in the group of hypovirulent micoviruses, and open the possibility to its use as a biological control agent of Fusarium wilt of carnation. The successful application of mycoviruses to the control of phytopathogenic fungi depends both on their ability to stably accumulate in the fungal host and on their efficient transmission among isolates in the natural fungal populations. FodV1 reaches a very high level of accumulation in the originally infected isolate. Results obtained in this work show that this high level remains stable over time, after successive subculture or passage through plant. Moreover, it has also been shown that FodV1 can be transferred by hyphal anastomosis among vegetatively compatible isolates. To evidence this, we have used the strain originally infected (Fod 116V+, donor), and another vegetatively compatible virus-free strain that had been previously transformed with a hygromycin resistance gene (Fod 77HygR, recipient). Results obtained show that FodV1 not only transfers to the recipient isolate, but also accumulates at a similar high level in it. Comparative analysis of isolates Fod 77HygR (virus-free) and Fod 77HygRV+ (virus-infected) proves that FodV1 induces in its new host similar phenotypic alterations that those described in the original infected isolate Fod 166V+. Another factor that could contribute to the spread of the mycovirus in the fungal population is the efficiency in the vertical transmission through asexual spores. In this Thesis we have analized the efficiency in the vertical transmission of FodV1 in both virus-infected isolates, Fod 116V+ and Fod 77HygRV+. Results show that this efficiency varies depending on the isolate considered. FodV1 is the first mycovirus associated to hypovirulence identified in the species F. oxysporum

Xpert MTB/RIF Ultra and Xpert MTB/RIF assays for extrapulmonary tuberculosis and rifampicin resistance in adults.

BACKGROUND: Xpert MTB/RIF Ultra (Xpert Ultra) and Xpert MTB/RIF are World Health Organization (WHO)-recommended rapid nucleic acid amplification tests (NAATs) widely used for simultaneous detection of Mycobacterium tuberculosis complex and rifampicin resistance in sputum. To extend our previous review on extrapulmonary tuberculosis (Kohli 2018), we performed this update to inform updated WHO policy (WHO Consolidated Guidelines (Module 3) 2020). OBJECTIVES: To estimate diagnostic accuracy of Xpert Ultra and Xpert MTB/RIF for extrapulmonary tuberculosis and rifampicin resistance in adults with presumptive extrapulmonary tuberculosis. SEARCH METHODS: Cochrane Infectious Diseases Group Specialized Register, MEDLINE, Embase, Science Citation Index, Web of Science, Latin American Caribbean Health Sciences Literature, Scopus, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform, the International Standard Randomized Controlled Trial Number Registry, and ProQuest, 2 August 2019 and 28 January 2020 (Xpert Ultra studies), without language restriction. SELECTION CRITERIA: Cross-sectional and cohort studies using non-respiratory specimens. Forms of extrapulmonary tuberculosis: tuberculous meningitis and pleural, lymph node, bone or joint, genitourinary, peritoneal, pericardial, disseminated tuberculosis. Reference standards were culture and a study-defined composite reference standard (tuberculosis detection); phenotypic drug susceptibility testing and line probe assays (rifampicin resistance detection). DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data and assessed risk of bias and applicability using QUADAS-2. For tuberculosis detection, we performed separate analyses by specimen type and reference standard using the bivariate model to estimate pooled sensitivity and specificity with 95% credible intervals (CrIs). We applied a latent class meta-analysis model to three forms of extrapulmonary tuberculosis. We assessed certainty of evidence using GRADE. MAIN RESULTS: 69 studies: 67 evaluated Xpert MTB/RIF and 11 evaluated Xpert Ultra, of which nine evaluated both tests. Most studies were conducted in China, India, South Africa, and Uganda. Overall, risk of bias was low for patient selection, index test, and flow and timing domains, and low (49%) or unclear (43%) for the reference standard domain. Applicability for the patient selection domain was unclear for most studies because we were unsure of the clinical settings. Cerebrospinal fluid Xpert Ultra (6 studies) Xpert Ultra pooled sensitivity and specificity (95% CrI) against culture were 89.4% (79.1 to 95.6) (89 participants; low-certainty evidence) and 91.2% (83.2 to 95.7) (386 participants; moderate-certainty evidence). Of 1000 people where 100 have tuberculous meningitis, 168 would be Xpert Ultra-positive: of these, 79 (47%) would not have tuberculosis (false-positives) and 832 would be Xpert Ultra-negative: of these, 11 (1%) would have tuberculosis (false-negatives). Xpert MTB/RIF (30 studies) Xpert MTB/RIF pooled sensitivity and specificity against culture were 71.1% (62.8 to 79.1) (571 participants; moderate-certainty evidence) and 96.9% (95.4 to 98.0) (2824 participants; high-certainty evidence). Of 1000 people where 100 have tuberculous meningitis, 99 would be Xpert MTB/RIF-positive: of these, 28 (28%) would not have tuberculosis; and 901 would be Xpert MTB/RIF-negative: of these, 29 (3%) would have tuberculosis. Pleural fluid Xpert Ultra (4 studies) Xpert Ultra pooled sensitivity and specificity against culture were 75.0% (58.0 to 86.4) (158 participants; very low-certainty evidence) and 87.0% (63.1 to 97.9) (240 participants; very low-certainty evidence). Of 1000 people where 100 have pleural tuberculosis, 192 would be Xpert Ultra-positive: of these, 117 (61%) would not have tuberculosis; and 808 would be Xpert Ultra-negative: of these, 25 (3%) would have tuberculosis. Xpert MTB/RIF (25 studies) Xpert MTB/RIF pooled sensitivity and specificity against culture were 49.5% (39.8 to 59.9) (644 participants; low-certainty evidence) and 98.9% (97.6 to 99.7) (2421 participants; high-certainty evidence). Of 1000 people where 100 have pleural tuberculosis, 60 would be Xpert MTB/RIF-positive: of these, 10 (17%) would not have tuberculosis; and 940 would be Xpert MTB/RIF-negative: of these, 50 (5%) would have tuberculosis. Lymph node aspirate Xpert Ultra (1 study) Xpert Ultra sensitivity and specificity (95% confidence interval) against composite reference standard were 70% (51 to 85) (30 participants; very low-certainty evidence) and 100% (92 to 100) (43 participants; low-certainty evidence). Of 1000 people where 100 have lymph node tuberculosis, 70 would be Xpert Ultra-positive and 0 (0%) would not have tuberculosis; 930 would be Xpert Ultra-negative and 30 (3%) would have tuberculosis. Xpert MTB/RIF (4 studies) Xpert MTB/RIF pooled sensitivity and specificity against composite reference standard were 81.6% (61.9 to 93.3) (377 participants; low-certainty evidence) and 96.4% (91.3 to 98.6) (302 participants; low-certainty evidence). Of 1000 people where 100 have lymph node tuberculosis, 118 would be Xpert MTB/RIF-positive and 37 (31%) would not have tuberculosis; 882 would be Xpert MTB/RIF-negative and 19 (2%) would have tuberculosis. In lymph node aspirate, Xpert MTB/RIF pooled specificity against culture was 86.2% (78.0 to 92.3), lower than that against a composite reference standard. Using the latent class model, Xpert MTB/RIF pooled specificity was 99.5% (99.1 to 99.7), similar to that observed with a composite reference standard. Rifampicin resistance Xpert Ultra (4 studies) Xpert Ultra pooled sensitivity and specificity were 100.0% (95.1 to 100.0), (24 participants; low-certainty evidence) and 100.0% (99.0 to 100.0) (105 participants; moderate-certainty evidence). Of 1000 people where 100 have rifampicin resistance, 100 would be Xpert Ultra-positive (resistant): of these, zero (0%) would not have rifampicin resistance; and 900 would be Xpert Ultra-negative (susceptible): of these, zero (0%) would have rifampicin resistance. Xpert MTB/RIF (19 studies) Xpert MTB/RIF pooled sensitivity and specificity were 96.5% (91.9 to 98.8) (148 participants; high-certainty evidence) and 99.1% (98.0 to 99.7) (822 participants; high-certainty evidence). Of 1000 people where 100 have rifampicin resistance, 105 would be Xpert MTB/RIF-positive (resistant): of these, 8 (8%) would not have rifampicin resistance; and 895 would be Xpert MTB/RIF-negative (susceptible): of these, 3 (0.3%) would have rifampicin resistance. AUTHORS' CONCLUSIONS: Xpert Ultra and Xpert MTB/RIF may be helpful in diagnosing extrapulmonary tuberculosis. Sensitivity varies across different extrapulmonary specimens: while for most specimens specificity is high, the tests rarely yield a positive result for people without tuberculosis. For tuberculous meningitis, Xpert Ultra had higher sensitivity and lower specificity than Xpert MTB/RIF against culture. Xpert Ultra and Xpert MTB/RIF had similar sensitivity and specificity for rifampicin resistance. Future research should acknowledge the concern associated with culture as a reference standard in paucibacillary specimens and consider ways to address this limitation

Horizontal and vertical transmission of the hypovirulence-associated mycovirus Fusarium oxysporum f. sp. dianthi virus 1

First Online 10 August 2018.Mycovirus Fusarium oxysporum f. sp. dianthi virus 1 (FodV1) has been recently described infecting isolate Fod 116 of Fusarium oxysporum f. sp. dianthi (Fod). FodV1 is a new member of the family Chrysoviridae, and its genome consists of four dsRNA segments ranging from 2.6 to 3.5 kb. Presence of high levels of FodV1 in its original fungal host correlated with alteration of some phenotypic traits, including virulence. In this work we have analysed if FodV1 can be transferred horizontally to another Fod isolate by hyphal anastomosis, and vertically through conidiation, and if the mycovirus accumulates in the recipient isolate at similar levels that those found in the donor one. Moreover, we have investigated if the new virus-infected isolate reproduces the same phenotypic alterations that the original virus-infected does. Results indicated that FodV1 transfers horizontally between compatible isolates by hyphal anastomosis, reaching a high level of accumulation in the recipient isolate, and vertically during sporogenesis. Presence of FodV1 in the new fungal host reduced the growth rate and altered the morphology of the colony on solid medium, and diminished the conidiation rate in liquid medium. More interestingly, FodV1 induced hypovirulence in its new fungal host. Results contained in this work constitute the basis for further research on the application of mycovirus FodV1 to the control of Fusarium wilt diseases.This research was supported by Grants AGL 2010–18279, from the Spanish Ministry of Science and Innovation, and AGL 2013–48980-R, from the Spanish Ministry of Economy and Competitiveness, co-funded by the European Union (FEDER funds).Peer reviewe

Identification of a micovirus in fusarium oxysporum f.sp. dianthi which affects phenotypic traits of the fungal host

Trabajo presentado en la 12th European Conference on Fungal Genetics (ECFG12), celebrada en Sevilla del 23 al 27 de marzo de 2014.N

Complete genome sequence of a novel dsRNA mycovirus isolated from the phytopathogenic fungus Fusarium oxysporum f. sp. dianthi

A novel double-stranded RNA (dsRNA) mycovirus, designated Fusarium oxysporum f. sp. dianthi mycovirus 1 (FodV1), was isolated from a strain of the phytopathogenic fungus F. oxysporum f. sp. dianthi. The FodV1 genome had four dsRNA segments, designated, from the largest to the smallest one, dsRNA 1, 2 3, and 4. Each one of these segments contained a single open reading frame (ORF). dsRNA 1 (3555 bp) and dsRNA 3 (2794 bp) encoded a putative RNA-dependent RNA polymerase (RdRp) and a putative coat protein (CP), respectively. dsRNA 2 (2809 bp) and dsRNA 4 (2646 bp) contained ORFs encoding hypothetical proteins (named P2 and P4, respectively) with unknown functions. Analysis of its genomic structure, homology searches of the deduced amino acid sequences, and phylogenetic analysis all indicated that FodV1 is a new member of the family Chrysoviridae. This is the first report of the complete genomic characterization of a mycovirus identified in the plant pathogen Fusarium oxysporum.This research was supported by Grants AGL2010-18279 and AGL2013-48980-R from the Spanish Ministry of Science and Innovation, co-funded by the European Union (FEDER funds). C.G. Lemus-Minor was the recipient of a JAE-Pre fellowship from CSIC, also co-funded with FEDER funds.Peer reviewe

Fusarium oxysporum f. sp. dianthi virus 1 Accumulation Is Correlated with Changes in Virulence and Other Phenotypic Traits of Its Fungal Host

Fusarium oxysporum f. sp. dianthi virus 1 (FodV1) was detected in isolate 116 (116V+) of Fusarium oxysporum f. sp. dianthi, reaching such a high accumulation level that it was clearly visible after agarose gel electrophoresis of total DNA extracts. FodV1 consists of four double-stranded RNA segments that correspond to a new mycovirus in the Chrysoviridae family. We obtained an isolate of F. oxysporum f. sp. dianthi 116 (116V−) with only a residual level of FodV1 RNA accumulation by single-conidia selection. Compared with 116V−, isolate 116V+ showed significant phenotypic alterations in vegetative growth and virulence. Thus, the presence of a high titer of mycovirus FodV1 was associated with a modified morphology and a reduced growth of the colonies on solid medium, and with a diminished conidiation in liquid medium. Inoculation of four susceptible carnation cultivars with either 116V− or 116V+ showed that the presence of a high titer of FodV1 was also correlated with a significantly reduced virulence of its fungal host. All of the results suggest that FodV1 could be associated with hypovirulence, identifying it as a potential biocontrol agent for Fusarium wilt of carnation. This is the first report of a mycovirus potentially associated with the induction of hypovirulence in the species F. oxysporum.This research was supported by grants AGL 2010-18279 and AGL 2013-48980-R from the Spanish Ministry of Science and Innovation, co-funded by the European Union (FEDER funds).Peer reviewe

Identificación de Micovirus en Fusarium oxysporum f. sp. dianthi que induce hipovirulencia

Trabajo presentado en el XVII Congreso de la Sociedad Española de Fitopatología, celebrado en Lleida del 7 al 10 de octubre de 2014.Los determinantes de virulencia en hongos fitopatógenos pueden estar asociados a factores cromosómicos y extracromosómicos. La presencia de moléculas de ARN de doble hebra (dsRNA) extracromosómicas en células fúngicas se ha asociado a la infección por virus (micovirus), algunos de los cuales inducen hipovirulencia en su hospedador. Los micovirus que inducen hipovirulencia tienen un gran potencial como herramientas de control biológico en enfermedades fúngicas, de ahí la importancia de identificar y caracterizar estos determinantes de virulencia en hongos fitopatógenos. Fusarium oxysporum f. sp. dianthi (Fod) es el agente causal de la marchitez vascular del clavel, la enfermedad más dañina de las que afectan este cultivo a nivel mundial. Las poblaciones de Fod muestran una alta diversidad genética y patogénica, que incluye la existencia de 10 razas fisiológicas, así como de grupos de virulencia dentro de algunas de ellas. El análisis de extractos de ácidos nucleicos totales de una amplia colección de aislados de Fod dio lugar a la identificación de un nuevo micovirus perteneciente a la familia Chrysoviridae, al que hemos denominado FodV1, en un aislado de raza 2 (Fod 116). Considerando que en la familia Chrysoviridae se han caracterizado miembros con capacidad de inducir hipovirulencia, en este trabajo hemos analizado el efecto que FodV1 ejerce sobre las características fenotípicas del hongo hospedador. Para ello se realizaron estudios comparados con las versiones con virus y sin virus (versión curada) del aislado Fod 116. Los resultados mostraron que la presencia de FodV1 tiene efectos importantes sobre el fenotipo del hongo, afectando la morfología y tamaño de la colonia, la pigmentación, y la tasa de conidiación. Más aún, los resultados de un test de patogenicidad con 5 cultivares de clavel (1 resistente y 4 susceptibles a Fod raza 2), indicaron que FodV1 induce hipovirulencia en Fod, aunque este efecto es cultivar-dependiente.Este trabajo ha sido financiado por fondos del Plan Nacional de Investigación otorgados por el Ministerio de Ciencia e Innovación (AGL2010-18279), cofinanciado con fondos FEDER (EU).N

Caracterización Molecular de un nuevo Micovirus en Fusarium oxysporum f. sp. dianthi

Trabajo presentado en el XVII Congreso de la Sociedad Española de Fitopatología, celebrado en Lleida del 7 al 10 de octubre de 2014.La búsqueda, identificación y caracterización de micovirus que infectan hongos fitopatógenos constituye una línea de investigación de importancia creciente debido a su posible utilización en estrategias de control biológico. El análisis de extractos de ácidos nucleicos totales de una amplia colección de aislados de Fusarium oxysporum f. sp. dianthi (Fod), obtenidos de áreas de cultivo de clavel del sur de España, resultó en la identificación de un elemento extracromosómico de ARN de doble hebra (dsRNA) en uno de los aislados (Fod 116). Para elucidar la secuencia de este elemento se utilizaron tres técnicas distintas: Single Primer Amplification Technique (SPAT), construcción de librerías de cDNA, y amplificaciones dirigidas. El uso combinado de estas técnicas dio como resultado la determinación de la secuencia genómica completa del virus identificado, que consta de 4 segmentos distintos de dsRNA, denominados dsRNA 1, 2, 3 y 4. La secuencia de estos 4 segmentos se analizó utilizando búsquedas BLAST, encontrando similitudes con otros micovirus de la familia Chrysoviridae, como Fusarium graminearum-China 9 (FgV-ch9) y Magnaporte oryzae chrysovirus 1 (MoCV1). Estos resultados evidencian la presencia en un aislado de Fod de un nuevo micovirus, al que hemos denominado Fusarium oxysporum f. sp. dianthi Virus 1 (FodV1). En este trabajo se presenta una descripción detallada de la estructura genómica de FodV1 y se analiza su relación filogenética con otros micovirus.Este trabajo ha sido financiado por fondos del Plan Nacional de Investigación otorgados por el Ministerio de Ciencia e Innovación (AGL2010-18279), cofinanciado con fondos FEDER (EUN

Optimal Economic Dispatch in Microgrids with Renewable Energy Sources

Due to the opening of the energy market and agreements for the reduction of pollution emissions, the use of microgrids attracts more attention in the scientific community, but the management of the distribution of electricity has new challenges. This paper considers different distributed generation systems as a main part to design a microgrid and the resources management is defined in a period through proposed dynamic economic dispatch approach. The inputs are obtained by the model predictive control algorithm considering variations of both pattern of consumption and generation systems capacity, including conventional and renewable energy sources. Furthermore, the proposed approach considers a benefits program to customers involving a demand restriction and the costs of regeneration of the pollutants produced by conventional generation systems. The dispatch strategy through a mathematical programming approach seeks to reduce to the minimum the fuel cost of conventional generators, the energy transactions, the regeneration of polluted emissions and, finally, includes the benefit in electricity demand reduction satisfying all restrictions through mathematical programming strategy. The model is implemented in LINGO 17.0 software (Lindo Systems, 1415 North Dayton Street, Chicago, IL, USA). The results exhibit the proposed approach effectiveness through a study case under different considerations

Horizontal and vertical transmission of the hypovirulence-associated Mycovirus Fusarium oxysporum f. sp. dianthi virus 1

Póster presentado en el XVIII Congreso de la Sociedad Española de Fitopatología (SEF), celebrado en Palencia del 20 al 23 de septiembre de 2016.Fusarium oxysporum f. sp. dianthi (Fod) is the causal agent of carnation wilt, the most devastating disease of this plant species. Recently, a “chryso-like” mycovirus, named Fusarium oxysporum f. sp. dianthi virus 1 (FodV1), has been identified in isolate Fod 116 of Fod. FodV1 genome has been fully sequenced, and it consists of 4 dsRNA segments ranging from 2.6 to 3.5 kb. Comparison of the naturally infected Fod 116 isolate (Fod 116V+) and a selected version with a very reduced level of viral dsRNA (Fod 116V-), evidenced that FodV1 significantly reduced the mycelial growth and conidiation rates, and the virulence on carnation of his fungal host, thus opening the possibility to its use as a biological control agent. In this work we have demonstrated that FodV1 can be transferred horizontally, through hyphal anastomosis between vegetatively compatible isolates, and vertically during conidiation, and that the new recipient isolate reproduces the same phenotypic alterations that the donor one. To assess the horizontal transmission, isolate Fod 77, compatible with the donor Fod116V+, was transformed with the hph gen (hygromycin resistant), and after hyphal anastomosis between both isolates, the presence of FodV1 in the new fungal host was evidenced by dsRNA purification and RT-qPCR. Comparative analysis of isolate Fod 77 with (V+) and without (V-) mycovirus FodV1, showed significant alterations in all the hypovirulence-associated traits analyzed. The frequency of mycovirus transmission through asexual spores has also been determined, showing significant differences between the two virus-containing isolates.Research supported by Grants AGL2010-18279 and AGL2013-48980-R, from the Spanish Ministry of Science and Innovation, co-funded by the European Union (FEDER funds).Peer Reviewe