Status de la familia Pythiaceae (Reino Straminipila) en Argentina : I. El género Pythium

197-211The genus Pythium (Pythiaceae (Peronosporomycetes-ex Oomycetes), KingdomStraminipila) includes important pathogens, affecting a wide range of hosts of economic value, causing damping-off and decline of herbaceous and wooded plants due to rootlets rot. In order to acquire a more comprehensive vision of Pythium in Argentina, a review and an updated report of recent progress in this matter was carried out since the first reports in the late XIX century till October 2009. Information was taken from printed and on line primary and secondary sources such as Proceedings of national and international Scientific Meetings, Bulletins from National Institutions and Universities, periodical Journals, books and data bases. The information was analyzed and categorized, thus updating the number of species of this genus, their geographical distribution, hosts affected, and symptoms. So far 18 species have been cited affecting, 247 hosts. The greatest number of hosts is affected by P. ultimum and P. debaryanum, followed by P. irregulare and P. aphanidermatum. The diversity of Pythium species in the world suggests that perhaps a wider variety of species, still not cited, could be present in Argentina. Projects dedicated to surveying the presence and identification of Pythium spp are necessary

Basal rot of Chamelaucium uncinatum caused by Phytophthora nicotianae in Argentina

35-37Since 1995 severe losses were recorded on the production of Chamelaucium uncinatum in the vicinity of La Plata. In 2010, with the aim to confirm the identity of the causal agent of Geraldton waxplant basal rot, molecular studies were added to the morphological observations of the pathogen. P. nicotianae was identified as the causal agent of the disease

Phytophthora nicotianae causando podridão de raiz e caule em Dieffenbachia picta em Buenos Aires, Argentina

327-331Dieffenbachia picta is a worldwide appreciated crop due to its ornamental value. In Argentina it is cultivated in warm provinces and in the outskirts of Buenos Aires city, where in spring 2007 a great amount of plants were lost in commercial greenhouses. Symptoms such as wilting and soaked lesions in the basal leaves began in four- to six-month-old plants causing plants to wilt due to basal stem and root rot processes. A Peronosporomycete was consistently isolated from diseased tissues. The pathogen was identified as Phytophthora nicotianae based on cultural characteristics, morphology of vegetative and reproductive structures, and on the analysis of the sequence of the nuclear ribosomal internal transcribed spacer (ITS) region. Pathogenicity tests were carried out and Koch's postulates were fulfilled. In complementary studies, the dieffenbachia varieties Alex, Compact, Camilla and Marianne were susceptible to the infection caused by P. nicotianae, whereas Tropic snow (D. amonea) was resistant. This is the first report of P. nicotianae causing stem and root rot of D. picta in Argentina and in the Americas

Post-harvest rots of pumpkin (Cucurbita moschata Duch.) “butternut” type. Enzymatic activity of Fusarium spp.

El zapallo tipo butternut (C. moschata) es el de mayor consumo en la Argentina. Durante el almacenamiento está expuesto a podredumbres ocasionadas por distintas especies de Fusarium con diferente virulencia. Para establecer alguna correlación entre la patogenicidady la actividad enzimática, con 22 cepas de dichas especies, se evaluó la producción "in vitro" de enzimas pectinolíticas y celulolíticas. Para la determinación se consideró la disminución de la viscosidad que produjo el filtrado de los hongos sobre sus respectivos sustratos. Se comprobó que todas las cepas produjeron ambos grupos de enzimas pero no se pudo establecer la correlación entre la capacidad patogénica de las mismas y su actividad enzimática.The “butternut" type pumpkin (Cucurbita moschata) is the most marketable vegetable in Argentina. Fusarium spp. exhibiting different pathogenicity, cause various rots during storage. Twenty two strains of Fusarium spp. were tested to study pectinolitic and cellulolitic enzymes production. The purpose of this work was to find any correlation between pathogenicity and enzyme activity. It was measured by reading viscosimetrical reduction after filtration of fungi over their corresponding substrate. The results indicated that all the strains, pathogenic and saprophitic, were able to produce both group of enzymes and no correlation was found between pathogenic and enzymatic activity.Facultad de Ciencias Agrarias y Forestale

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Mancha de la hoja de <i>Limonium sinuatum</i> en la Argentina

Limonium sinuatum (L) Mill (“flor de pa­pel”, “estátice”) se cultiva como flor para corte en invernaderos de la provincia de Buenos Aires. De manera reiterada, desde hace algu­nos años las plantaciones sufren los efectos de una enfermedad que compromete las ho­jas y las varas florales, reduciendo notable­mente el área fotosintética y la calidad de las mismas. En ataques severos las flores resul­tan no comerciables y puede llegar a produ­cirse la muerte de las plantas. La infección comienza en las hojas más viejas, que se encuentran en contacto con el suelo, y luego avanza hacia las hojas centra­les y la panícula floral. Se comprobó que el rastrojo que queda en el terreno constituye una im portante fuente de infección y que, al repetir el cultivo se producen ataques más severos. En estos casos las hojas centrales de la roseta, que retienen la humedad, se atizonan antes de la formación de las flores.Facultad de Ciencias Agrarias y Forestale

Status of the Pythiaceae (Straminipila) in Argentina: I. The GenusPythium

The genus Pythium (Pythiaceae (Peronosporomycetes - ex Oomycetes), Kingdom Straminipila) includes important pathogens, affecting a wide range of hosts of economic value, causing damping-off and decline of herbaceous and wooded plants due to rootlets rot. In order to acquire a more comprehensive vision of Pythium in Argentina, a review and an updated report of recent progress in this matter was carried out since the first reports in the late XIX century till October 2009. Information was taken from printed and on line primary and secondary sources such as Proceedings of national and international Scientific Meetings, Bulletins from National Institutions and Universities, periodical Journals, books and data bases. The information was analyzed and categorized, thus updating the number of species of this genus, their geographical distribution, hosts affected, and symptoms. So far 18 species have been cited affecting, 247 hosts. The greatest number of hosts is affected by P. ultimum and P. debaryanum, followed by P. irregulare and P. aphanidermatum. The diversity of Pythium species in the world suggests that perhaps a wider variety of species, still not cited, could be present in Argentina. Projects dedicated to surveying the presence and identification of Pythium spp are necessary.<br>El género Pythium (Pythiaceae (Peronosporomycetes-ex Oomycetes), Straminipila) incluye patógenos que afectan hospedantes de importancia económica, ocasionando damping off en pre y postemergencia de plántulas de almácigo y el declinamiento de plantas herbáceas y adultas por destrucción de las raíces absorbentes. Con la finalidad de conocer el estado actual de la información disponible sobre este género en Argentina, se llevó a cabo una revisión desde los primeros reportes a fines del siglo XIX hasta octubre de 2009. Se consultaron fuentes primarias y secundarias de información escrita y electrónica: presentaciones en congresos nacionales e internacionales, publicaciones periódicas nacionales e internacionales, boletines de instituciones y universidades, libros y bases de datos. La información obtenida fue categorizada y analizada permitiendo conocer el número de especies de este género, su distribución geográfica y por tipo de cultivos, relaciones hospedante-patógeno involucradas y la sintomatología observada. Se encuentran citadas 18 especies que afectan a 247 hospedantes. Un elevado número de hospedantes fueron afectados por P. ultimum y P. debaryanum, seguidos por P. irregulare y P. aphanidermatum. La diversidad de especies de Pythium en el mundo sugiere que un mayor número de especies podrían estar presentes en el país, siendo necesario su relevamiento e identificación

<i>Alternaria dianthicola</i> en el clavel en la Argentina

El clavel (Dianthus caryophyllus L) es uno de los principales cultivos de flor para corte en la Argentina. El mismo se realiza principalmente en la provincia de Buenos Ai­res, en los alrededores de las ciudades de Buenos Aires y La Plata. Durante los últimos años ha aparecido una patología que afecta a la producción y calidad de las flores. Los síntomas más desta­cados se observan en los pimpollos, los cua­les detienen el proceso de maduración, se atizonan y muestran los ápices de los sépalos y los pétalos necrosados y de color marrón claro. En las hojas se presentan manchas, que se inician en los bordes y en los ápices, se hacen confluentes y progresivamente pueden cubrir toda la lámina. También se produce este tipo de manchas sobre los tallos, en sentido longitudinal. En todos los casos son de color amarillo a marrón claro, con bordes más oscu­ros. En condiciones de humedad, sobre estas manchas, al igual que sobre los pétalos y los sépalos afectados, se puede observar el signo de la enfermedad, consistente en el micelio, conidióforos y conidios del hongo causante del proceso.Facultad de Ciencias Agrarias y Forestale