1,720,963 research outputs found
Fusariosis de la espiga : incidencia y severidad en distintos cultivares de trigo según fechas de siembra. Oliveros, campaña 2016-2017
Get PDFEl objetivo del presente trabajo fue caracterizar el comportamiento de algunos cultivares comerciales de trigo frente a la fusariosis de la espiga según fechas de siembra.Fil: Castellarin, Julio Manuel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Oliveros; ArgentinaFil: Incremona, Miriam. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Oliveros; Argentina. Universidad Nacional de Rosario.Facultad de Ciencias Agrarias. Cátedra de Fitopatología; ArgentinaFil: Gonzalez, Mirian del Pilar. Universidad Nacional de Rosario.Facultad de Ciencias Agrarias. Cátedra de Fitopatología; Argentina. Universidad Nacional de Rosario. Carrera del Investigador Científico; ArgentinaFil: Ferraguti, Facundo Javier. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Oliveros; Argentin
Enfermedades foliares en trigo: evaluación del comportamiento de cultivares comerciales en tres fechas de siembra. Oliveros, campaña 2016/17
Get PDFEl objetivo del presente trabajo fue evaluar el comportamiento de los diferentes cultivares comerciales de trigo pan frente a las enfermedades foliares en tres fechas de siembra en la EEA Oliveros INTA.Fil: Gonzalez, Mirian del Pilar. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Oliveros; Argentina. Universidad Nacional de Rosario.Facultad de Ciencias Agrarias. Cátedra de Fitopatología; Argentina. Universidad Nacional de Rosario. Carrera del Investigador Científico; ArgentinaFil: Castellarin, Julio Manuel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Oliveros; ArgentinaFil: Incremona, Miriam. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Oliveros; Argentina. Universidad Nacional de Rosario.Facultad de Ciencias Agrarias. Cátedra de Fitopatología; ArgentinaFil: Ferraguti, Facundo Javier. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Oliveros; Argentin
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Morphological, molecular and physiological characterization of the Colletotrichum / Glomerella - Glycine max system and its bio-epidemiological relationship with other hosts in the core producing area of Argentina
No full textLas enfermedades constituyen un factor limitante para la producción vegetal tanto en el
rendimiento como en la calidad de la semilla de cereales y oleaginosos. La antracnosis es una
enfermedad asociada al cultivo de soja y maíz, causada por las especies de hongos que conforman
un complejo conocido como enfermedades de fin de ciclo (EFC). El complejo fúngico
Glomerella/Colletotrichum (G/C) es un binomio constituido por un Ascomycota (fase sexual,
perfecta o teleomorfo) y un Deuteromycota (fase asexual, imperfecta o anamorfo), que causa
antracnosis en diversas especies vegetales de las familias Fabaceae, Poaceae, Solanaceae y
Rosaceae. Este complejo G/C muestra amplia variabilidad genética y especificidad fisiológica
al interactuar con diferentes genotipos de un mismo y/o diferentes hospedantes. Los objetivos
del trabajo fueron a)Validar morfológica y molecularmente las identidades de la colección de
aislados del complejo G/C obtenidos en plantas sintomáticas de diferentes familias y especies de
hospedantes y diversos ambientes de la zona núcleo; b) Caracterizar el comportamiento
(avirulencia/virulencia) de los diversos aislados del complejo fúngico y la reacción
(resistencia/susceptibilidad) de los hospedantes en base a la observación fenotípica e identificar
fuentes de resistencia a la enfermedad en los cultivos evaluados y c) Evaluar el complejo G/Cy
sus interacciones bajo condiciones seminaturales en una rotación soja – maíz. Durante dos ciclos
agrícolas, se evaluaron las asociaciones resultantes de la interacción de 3 genotipos de soja y 5
híbridos de maíz con 6 aislados G/C obtenidos de tallos sintomáticos de ambos cultivos y de
cítricos, provenientes de las provincias de Santa. Fe, Buenos Aires, Córdoba y Entre Ríos. La
identidad fue propuesta por macro y micromorfología y validada molecularmente por RAPDs y
secuenciación de amplicones de ITs. Las inoculaciones en soja se realizaron por herida en el
estado fenológico de V3. Las evaluaciones se realizaron según los parámetros de Incidencia (IE)
y Severidad de entrenudos (SE). Las inoculaciones en maíz se realizaron con jeringa en el estado
Vt y R1. Se evaluó IE % y SE % cada 10 días posterior a la inoculación hasta finalizar el ciclo del cultivo. En ambos cultivos (soja y maíz) se pudo determinar una Escala de 5 grados para
cuantificar severidad de antracnosis en entrenudos. Tanto los cultivares de soja como los de maíz
mostraron diferencias en su respuesta de resistencia y susceptibilidad, expresados en IE y SE
promedio frente al patógeno, y se detectaron además interacciones específicas significativas. Los
aislados de C. truncatum y C. gloeosporioides provenientes de cultivos de soja y de mandarina
fueron los más virulentos en las inoculaciones de maíz. Mientras en soja, las cepas de C.
graminicola, C. gloeosporioides y C. truncatum resultaron virulentas según la severidad de
antracnosis en los entrenudos. Las infecciones se produjeron con mayor severidad en el segundo
entrenudo avanzado hacia el ápice y hacia la base. Para el cumplimiento del tercer objetivo se
realizó un ensayo en parcelas bajo cubierta antigranizo, simulando condiciones naturales, donde
se sembraron los tres genotipos de soja sobre rastrojo de maíz infectado independientemente con
cinco cepas de G/C provenientes de hospedantes maíz y soja. Estos resultados mostraron que los
genotipos de soja se infectaron y expresaron síntomas de antracnosis causadas por aislados de
diferentes hospedantes y zonas agroecológicas, registrándose diferencias significativas en todas
las interacciones. En este sistema de rotación maíz – soja (ambos hospedantes de G/C), el rastrojo
de maíz infectado de antracnosis resultó efectivo como fuente de inóculo primario de C.
graminicola, C. truncatum y C. gloeosporioides e iniciar un proceso patógenico en los genotipos
de soja. Demostrando un riesgo epidemiológico para un sistema productivo basado en la
alternancia de cereales y oleaginosos, implementado y generalizado entre los productores de la
región centro. Por ello, la determinación de genotipos de soja y maíz con respuestas diferenciales
(R, MR/MS y S) frente a diferentes cepas del patógeno, permitirá su incorporación en futuros
programas de mejoramiento.Glycine max y su relación bio-epidemiológica con otros hospedantes en la zona productora
núcleo de Argentina.
Diseases constitute a limiting factor for plant production, both in the yield and quality of cereal
and oilseed seeds. Anthracnose is a disease associated with the cultivation of soybeans and corn,
caused by the species of fungi that make up a complex known as end-of-cycle diseases (CFEs).
The Glomerella / Colletotrichum (G/C) fungal complex is a binomial consisting of an
Ascomycota (sexual, perfect or teleomorphic phase) and a Deuteromycota (asexual, imperfect or
anamorphic phase), which causes anthracnose in various plant species of the Fabaceae families,
Poaceae, Solanaceae and Rosaceae. This G/C complex shows wide genetic variability and
physiological specificity when interacting with different genotypes of the same and / or different
hosts. The objectives of the work were a) To validate morphologically and molecularly the
identities of the collection of isolates of the G/C complex in symptomatic plants of different host
families and species and various environments of the core zone; b) Characterize the behavior
(avirulence / virulence) of the various isolates of the fungal complex and the reaction (resistance
/ susceptibility) of the hosts based on phenotypic observation and identify sources of resistance
to the disease in the evaluated crops and c) Evaluate the G/C complex and its interactions under
semi-natural conditions in a soybean-corn rotation. During two agricultural cycles, the
associations resulting from the interaction of 3 soybean genotypes and 5 maize hybrids with 6
G/C isolates obtened from symptomatic stems of both crops and citrus fruits from the Santa Fe,
Buenos Aires, Córdoba and Entre Ríos provinces, were evaluated. The identity was proposed by
macro and micro-morphology and molecularly validated by RAPDs and ITS amplicon
sequencing. Soybean inoculations were performed by wound in the phenological state of V3. The
evaluations were carried out according to the Incidence (IE) and Internode Severity (SE)
parameters. Corn inoculations were performed with a syringe in the Vt and R1 state. IE% and
SE% were evaluated every 10 days after inoculation until the end of the cultivation cycle. In both
crops (soybeans and corn), a 5-degree Scale could be determined to quantify anthracnose severity
in internodes. Both soybean and corn cultivars showed differences in their resistance and susceptibility response, expressed in average IE and SE against the pathogen, and significant
specific interactions were also detected. Isolates of C. truncatum and C. gloeosporioides from
soybean and mandarin crops were the most virulent in maize inoculations. While in soybeans,
the strains of C. graminicola and C. gloeosporioides and C. truncatum were virulent according
to the severity of anthracnose in the internodes. Infections occurred more severely in the second
internode advanced towards the apex and towards the base. To fulfill the third objective, a trial
was carried out in plots under hail cover, simulating natural conditions, where the 3 soybean
genotypes were planted on corn stubble independently infected with 5 G / C strains from corn
and soybean hosts. The results showed that soybean genotypes were infected and expressed
anthracnose symptoms caused by isolates from different hosts and agro-ecological zones,
registering significant differences in all interactions. In this corn-soybean rotation system (both
G/C hosts), anthracnose-infected corn stubble was effective as a source of primary inoculum for
C. graminicola, C. truncatum and C. gloeosporioides and to start a pathogenic process in the
soybean genotypes. Demonstrating an epidemiological risk for a production system based on the
alternation of cereals and oilseeds, implemented and widespread among producers in the central
region. Therefore, the determination of soybean and corn genotypes with differential responses
(R, MR / MS and S) against different strains of the pathogen, will allow their incorporation in
future breeding programs.Fil: Apellido, Nombre. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; ArgentinaIncremona, Miriam. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; Argentin
Colletotrichum sp. ASSOCIATED WITH SOYBEAN AND CORN ANTHRACNOSE IN THE PAMPAS REGION OF ARGENTINA
Get PDFColletotrichum species (C.) exhibit considerable genetic variability, causing diseases in different hosts and showing physiological specificity between isolates that interact with different genotypes of the same crop. The objective of this study was to identify Colletotrichum isolates collected from symptomatic plants of various plant species and environments in the central region of Argentina. Isolates were obtained from symptomatic stems of soybean, corn, alfalfa, and citrus plants. Fungal identity was confirmed through macro- and micromorphological analysis, as well as molecular techniques including by RAPD and sequencing of ITS1 and ITS4 fragments amplified by PCR. The identified Colletotrichum species included: C. truncatum and C. gloeosporioides in soybean, C. graminicola in corn, C. gloeosporioides in tangerine, and C. truncatum in alfalfa. These results highlight the plasticity of this pathogenic complex and the epidemiological risk posed by corn-soybean crop rotation for the development and severity of anthracnose.Colletotrichum species (C.) exhibit considerable genetic variability, causing diseases in different hosts and showing physiological specificity between isolates that interact with different genotypes of the same crop. The objective of this study was to identify Colletotrichum isolates collected from symptomatic plants of various plant species and environments in the central region of Argentina. Isolates were obtained from symptomatic stems of soybean, corn, alfalfa, and citrus plants. Fungal identity was confirmed through macro- and micromorphological analysis, as well as molecular techniques including by RAPD and sequencing of ITS1 and ITS4 fragments amplified by PCR. The identified Colletotrichum species included: C. truncatum and C. gloeosporioides in soybean, C. graminicola in corn, C. gloeosporioides in tangerine, and C. truncatum in alfalfa. These results highlight the plasticity of this pathogenic complex and the epidemiological risk posed by corn-soybean crop rotation for the development and severity of anthracnose
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
