First Report of Colletotrichum gloeosporioides Causing Anthracnose of Tejocote (Crataegus gracilior) Fruits in Mexico

Crataegus, is a genus classified in family Rosaceae and includes several tree species commonly called Tejocote that are widely cultivated for their pome fruits in Mexico. During fall of 2014, 2015, and 2016, severe symptoms of anthracnose were observed on approx. 60% of tejocote (Crataegus gracilior) fruits in an orchard located in Tulancingo, Oaxaca, Mexico. Affected fruits showed sunken, prominent, dark brown to black necrotic lesions, and were exuding salmon spore masses. To isolate the fungus, small pieces from tissue adjacent to the lesions of 10 symptomatic fruits were excised and surface disinfested by immersion in a 1% sodium hypochlorite solution for 2 min, rinsed three times in sterile distilled water, placed in Petri plates containing potato dextrose agar (PDA), and incubated at 25ºC for 5 to 7 days in darkness. Mycelial plugs were excised from the edge of the actively growing fungal colony and aseptically transferred to fresh PDA medium and incubated at 25°C for 6 days. Five monoconidial cultures were obtained by transferring germinated spores to Petri plates with fresh PDA. One isolate was selected as representative for morphological and molecular identification. Colonies of pure cultures exhibited greyish-white aerial mycelium and abundant salmon-pink conidial masses. Conidia (n= 100) were subcylindrical, hyaline, straight, one-celled, with rounded ends, measuring 13.6 to 17.7 × 4.4 to 5.9 μm. Conidial appressoria were ovoid and brown to dark brown. Based on morphological characteristics, the fungus was identified within the Colletotrichum gloeosporioides species complex (Weir et al. 2012). The isolate was designated UACH-177 and deposited in the Culture Collection of Phytopathogenic Fungi at the Chapingo Autonomous University. For molecular identification, the ITS region (White et al. 1990), and fragments of (Apn2) (Rojas et al. 2010), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and β-tubulin 2 (TUB2) genes (Weir et al. 2012) were amplified by PCR, and sequenced. The sequences were deposited in GenBank (Accessions numbers ITS:MG821312; Apn2:MG821310; GAPDH:MG821311; and TUB2:MG821313). A phylogenetic analysis using Bayesian inference and including published ITS, Apn2, GAPDH, and TUB2 data for C. gloeosporioides and other Colletotrichum species was performed. The phylogenetic analysis showed the sequences were grouped into the clade of C. gloeosporioides. To confirm the pathogenicity of the fungus, 20 tejocote fruits were surface disinfested by immersion in a 1% sodium hypochlorite solution for 1 min, washed three times with sterile distilled water and dried on sterilized filter paper. Inoculations were performed by deposition of 10 μl of a conidial suspension (106 spores ml-1) on the fruit surface. Ten fruit were mock inoculated with distilled water as a control. All fruits were kept in a moist chamber at 25°C for 10 days. Pathogenicity test was repeated twice. Disease symptoms were observed on all inoculated fruit after 7 days, whereas control fruit did not develop symptoms. Fungal colonies were re-isolated from all symptomatic fruits and were found to be morphologically identical to the original isolate inoculated on tejocote fruits, thus fulfilling Koch´s postulates. In Mexico, García-Alvarez (1976) reported Colletotrichum sp. on fruits of Crataegus mexicana, however, that report was not supported by morphological characterization nor pathogenicity tests. To our knowledge, this is the first report of C. gloeosporioides causing anthracnose of Crataegus gracilior in Mexico and worldwide.Fil: Nieto López, Edgar Humberto. University of Nebraska; Estados UnidosFil: Everhart, Sydney. University of Nebraska; Estados UnidosFil: Ayala Escobar, Victoria. Colegio de Postgraduados; MéxicoFil: Camacho Tapia, Moises. Universidad Autónoma Chapingo; MéxicoFil: Bernardi Lima, Nelson. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Nieto Angel, Raúl. Universidad Autónoma Chapingo; MéxicoFil: Tovar Pedraza, Juan Manuel. Universidad Autónoma Chapingo; Méxic

First report of white thread blight caused by ceratobasidium niltonsouzanum on yerba mate in Argentina

Yerba mate (Ilex paraguariensis A.St.-Hil.) is a native species of the subtropical and temperate regions of South America. In the Misiones province, in Northeastern Argentina, yerba mate is an important agricultural crop grown on approximately 150,000 ha. In March 2019, diseased leaves and stems from four fields near Comandante Andresito city, were received for diagnosis at the Instituto de Patología Vegetal (IPAVE) and Instituto Nacional de Tecnología Agropecuaria (INTA), Argentina. Disease symptoms were accompanied by white mycelium threads in the young branches. The threads extended longitudinally, along the surface of the stem, which later developed into leaf blight, with leaves hanging on white threads of fungal hyphae. Symptoms were the same in samples from all four fields (100% prevalence) and disease incidence varied between 50 and 80%. Isolations were performed by transferring small sections of diseased plant tissue, disinfested in 1.5% sodium hypochlorite for 1 min, washed with sterile distilled water, then transferred to Petri dishes containing potato dextrose agar (PDA), and incubated at 25°C, in the dark. Over ten isolations from five plants, eight Rhizoctonia-like colonies were isolated. Pure cultures were obtained by transferring hyphal tips to plates containing PDA. Four isolates (IPAVE 0075, 0076, 0077 and 0078) were selected as representatives for characterization and deposited at the Culture Collection of Instituto de Patologia Vegetal ? IPAVE (Córdoba, Argentina). On PDA, the colonies initially had white aerial mycelia and concentric rings were visible on the reverse side. The colonies turned brown after approximately 30 days. Hyphae were branched with 90° angulation, a typical character of members of the form genus Rhizoctonia. For molecular identification, the internal transcribed spacer (ITS) region was amplified by PCR (White et al. 1990), and sequenced. Phylogenetic analyses using Bayesian inference grouped the isolates from yerba mate with the type species of Ceratobasidium niltonsouzanum (Melo et al. 2018) with high posterior probability (0.98). Pathogenicity testing was conducted using toothpicks colonized with the pathogen (Souza et al. 2009). Inoculum was produced on PDA medium by allowing the isolates to colonize sterilized toothpicks placed on PDA, and incubating for 7 days at 25°C, under a 12h photoperiod. Twenty four-month old yerba mate plants were inoculated by inserting the colonized toothpicks into the base of the leaf petiole. Plants were kept in the greenhouse at 25°C, under high humidity, for 30 days and observed daily (Souza et al. 2009). Four control plants were mock-inoculated using only sterilized toothpicks. White thread blight symptoms were observed on all inoculated plants after 20 days, whereas control plants remained symptomless. C. niltonsouzanum was re-isolated from symptomatic tissue (leaves and petiole) of the inoculated plants, with a frequency of 100%, thereby validating Koch?s postulates. The experiment was performed twice. C. niltonsouzanum has been reported as a pathogen on numerous crops including Coffea arabica, Camellia sinensis, Azadirachta indica and Eugenia uniflora in Brazil (Melo et al 2018). This work improves knowledge surrounding the etiology of the disease associated with yerba mate in Argentina, which is essential information for the identification of appropriate management practices. To our knowledge, this is the first report of C. niltonsouzanum causing white thread blight of yerba mate in Argentina and worldwide.Fil: Bernardi Lima, Nelson. 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: Kryvenki, Mario Angel. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Misiones. Estacion Experimental Agropecuaria Cerro Azul. Agencia de Extension Rural Apostoles; ArgentinaFil: Conforto, Erica Cinthia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Serri, Dannae. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Unidad de Fitopatología y Modelización Agrícola - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Fitopatología y Modelización Agrícola; ArgentinaFil: Kramer, Rodrigo. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Roca, Monica Esther María. Universidad Nacional La Rioja. Servicio Nacional de Sanidad y Calidad Agroalimentaria; ArgentinaFil: Vargas Gil, Silvina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Unidad de Fitopatología y Modelización Agrícola - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Fitopatología y Modelización Agrícola; Argentin

First draft genome of \u3ci\u3eThecaphora frezii\u3c/i\u3e, causal agent of peanut smut disease

Objectives: The fungal pathogen Thecaphora frezii Carranza & Lindquist causes peanut smut, a severe disease currently endemic in Argentina. To study the ecology of T. frezii and to understand the mechanisms of smut resistance in peanut plants, it is crucial to know the genetics of this pathogen. The objective of this work was to isolate the pathogen and generate the first draft genome of T. frezii that will be the basis for analyzing its potential genetic diversity and its interaction with peanut cultivars. Our research group is working to identify peanut germplasm with smut resistance and to understand the genetics of the pathogen. Knowing the genome of T. frezii will help analyze potential variants of this pathogen and contribute to develop enhanced peanut germplasm with broader and long-lasting resistance. Data description: Thecaphora frezii isolate IPAVE 0401 (here referred as T.f.B7) was obtained from a single hyphal-tip culture, its DNA was sequenced using Pacific Biosciences Sequel II (PacBio) and Illumina NovaSeq6000 (Nova). Data from both sequencing platforms were combined and the de novo assembling estimated a 29.3 Mb genome size. Completeness of the genome examined using Benchmarking Universal Single-Copy Orthologs (BUSCO) showed the assembly had 84.6% of the 758 genes in fungi_odb10

Uso de biocarbón en la estimulación de la microbiota del suelo y el manejo del carbón del maní (Thecaphora frezii)

Dada la importancia del maní (Arachis hypogaea) para la economía de la provincia de Córdoba, surge el interés por dotar de valor agregado a los residuos que genera este sector productivo. Actualmente, se han desarrollado unidades de generación de energía eléctrica que utilizan la biomasa de cáscara de maní. A pesar de la eficiencia del proceso, las cenizas (C) que son el subproducto que se genera, se acumulan en grandes volúmenes que no tiene destino concreto. Por otra parte, una alternativa es la producción de biocarbón (BC), material producido por la pirólisis de biomasa con la finalidad de ser utilizado como enmienda de suelos. Su aplicación ha registrado aumento de la fertilidad e intercambio catiónico en suelos pobres en materia orgánica, retención de agua y nutrientes, y mejora del pH en suelos ácidos. A su vez, ha demostrado ser promisorio en la supresión de enfermedades por diversos mecanismos, inducción de resistencia sistémica, aumento de la abundancia y/o actividad de microorganismos benéficos, efecto fungitóxico por sus componentes químicos y/o por su estructura porosa que provee un hábitat que propicia el incremento de la microbiota nativa. Dado que el cultivo de maní se vio afectado en la última década por el carbón del maní (Thecaphora frezii), siendo la enfermedad del rizoplano de mayor prevalencia e intensidad, una opción para prevenirla es actuar sobre el suelo, con la finalidad de inactivar al patógeno. En este sentido, la aplicación de C o BC obtenidos a través del tratamiento de cáscaras de maní, podrían ser estrategias promisorias en la reducción de la incidencia de carbón del maní potenciando las aplicaciones de estos subproductos. El objetivo fue evaluar el efecto de C y BC en la actividad microbiana edáfica, parámetros fisiológicos y de respuesta al carbón del maníInstituto de Patología VegetalFil: Serri, Dannae Lilia. 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: Guzzo, María Carla. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Estudios Agropecuarios; ArgentinaFil: Bernanrdi Lima, Nelson. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFYMA); ArgentinaFil: Milesi Delaye, Luis Antonio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino; ArgentinaFil: Andriulo, Adrian Enrique. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino. Pergamino, Buenos Aires; ArgentinaFil: Fermanelli, C. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Tecnológica Nacional. Facultad Regional Córdoba. Centro de Investigación y Tecnología Química; ArgentinaFil: Saux, C. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Tecnológica Nacional. Facultad Regional Córdoba. Centro de Investigación y Tecnología Química; ArgentinaFil: Dominchin, M.F. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Meriles, J.M. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Vargas Gil, Silvina. 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); Argentin

The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey (eBOSS); the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020, and will be followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14 happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov 2017 (this is the "post-print" and "post-proofs" version; minor corrections only from v1, and most of errors found in proofs corrected

Measurement of the p-pbar -> Wgamma + X cross section at sqrt(s) = 1.96 TeV and WWgamma anomalous coupling limits

The WWgamma triple gauge boson coupling parameters are studied using p-pbar -> l nu gamma + X (l = e,mu) events at sqrt(s) = 1.96 TeV. The data were collected with the DO detector from an integrated luminosity of 162 pb^{-1} delivered by the Fermilab Tevatron Collider. The cross section times branching fraction for p-pbar -> W(gamma) + X -> l nu gamma + X with E_T^{gamma} > 8 GeV and Delta R_{l gamma} > 0.7 is 14.8 +/- 1.6 (stat) +/- 1.0 (syst) +/- 1.0 (lum) pb. The one-dimensional 95% confidence level limits on anomalous couplings are -0.88 < Delta kappa_{gamma} < 0.96 and -0.20 < lambda_{gamma} < 0.20.Comment: Submitted to Phys. Rev. D Rapid Communication

Measurement of the ttbar Production Cross Section in ppbar Collisions at sqrt{s} = 1.96 TeV using Kinematic Characteristics of Lepton + Jets Events

We present a measurement of the top quark pair ttbar production cross section in ppbar collisions at a center-of-mass energy of 1.96 TeV using 230 pb**{-1} of data collected by the DO detector at the Fermilab Tevatron Collider. We select events with one charged lepton (electron or muon), large missing transverse energy, and at least four jets, and extract the ttbar content of the sample based on the kinematic characteristics of the events. For a top quark mass of 175 GeV, we measure sigma(ttbar) = 6.7 {+1.4-1.3} (stat) {+1.6- 1.1} (syst) +/-0.4 (lumi) pb, in good agreement with the standard model prediction.Comment: submitted to Phys.Rev.Let

Measurement of the ttbar Production Cross Section in ppbar Collisions at sqrt(s)=1.96 TeV using Lepton + Jets Events with Lifetime b-tagging

We present a measurement of the top quark pair ($t\bar{t}$) production cross section ($\sigma_{t\bar{t}}$) in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV using 230 pb$^{-1}$ of data collected by the D0 experiment at the Fermilab Tevatron Collider. We select events with one charged lepton (electron or muon), missing transverse energy, and jets in the final state. We employ lifetime-based b-jet identification techniques to further enhance the $t\bar{t}$ purity of the selected sample. For a top quark mass of 175 GeV, we measure $\sigma_{t\bar{t}}=8.6^{+1.6}_{-1.5}(stat.+syst.)\pm 0.6(lumi.)$ pb, in agreement with the standard model expectation.Comment: 7 pages, 2 figures, 3 tables Submitted to Phys.Rev.Let

Search for R-parity violating supersymmetry via the LLE couplings lambda_{121}, lambda_{122} or lambda_{133} in ppbar collisions at sqrt(s)=1.96 TeV

A search for gaugino pair production with a trilepton signature in the framework of R-parity violating supersymmetry via the couplings lambda_121, lambda_122, or lambda_133 is presented. The data, corresponding to an integrated luminosity of L~360/pb, were collected from April 2002 to August 2004 with the D0 detector at the Fermilab Tevatron Collider, at a center-of-mass energy of sqrt(s)=1.96 TeV. This analysis considers final states with three charged leptons with the flavor combinations eel, mumul, and eetau (l=e or mu). No evidence for supersymmetry is found and limits at the 95% confidence level are set on the gaugino pair production cross section and lower bounds on the masses of the lightest neutralino and chargino are derived in two supersymmetric models.Comment: 9 pages, 4 figures (fig2 includes 3 subfigures

Search for right-handed W bosons in top quark decay

We present a measurement of the fraction f+ of right-handed W bosons produced in top quark decays, based on a candidate sample of $t\bar{t}$ events in the lepton+jets decay mode. These data correspond to an integrated luminosity of 230pb^-1, collected by the DO detector at the Fermilab Tevatron $p\bar{p}$ Collider at sqrt(s)=1.96 TeV. We use a constrained fit to reconstruct the kinematics of the $t\bar{t}$ and decay products, which allows for the measurement of the leptonic decay angle $\theta^*$ for each event. By comparing the $\cos\theta^*$ distribution from the data with those for the expected background and signal for various values of f+, we find f+=0.00+-0.13(stat)+-0.07(syst). This measurement is consistent with the standard model prediction of f+=3.6x10^-4.Comment: Submitted to Physical Review D Rapid Communications 7 pages, 3 figure