Abstract Athyrium decurtatum var. platense (= Thelypteris decurtata subsp. platensis) is transferred to the genus Amauropelta and raised to the species level based on morphological, palynological and geographical evidences. This fern species is endemic to the Delta of Paraná district, belonging to the Esteros del Iberá biogeographic province in the Southern Cone of South America.

Resumo Athyrium decurtatum var. platense (= Thelypteris decurtata subsp. platensis) é transferida para o gênero Amauropelta e elevada ao nível de espécie com base em estudos morfológicos, palinológicos e geográficos. Esta espécie é endêmica do distrito Delta do Paraná, pertencendo à província biogeográfica dos Esteros del Iberá, no Cone Sul da América do Sul.

Abstract The recovery of soil spores is a strategy to strengthen in decline or disappeared populations from natural environments. In this work, we analyzed 25 soil samples extracted from a patch of gallery forest in an “albardón” of Punta Lara Reserve, Buenos Aires. The samples were distributed in 50 Petri dishes, 25 exposed to controlled temperature and light and another 25 kept in darkness. To contribute to the identification of gametophytes and sporophytes, spores of the local species were cultured in vitro. In 18 months of trial, the appearance of gametophytes and sporophytes was observed, in a greater proportion those belonging to a dominant species in the community: Doryopteris concolor. Numerous gametophytes and sporophytes from Gastoniella chaerophylla were also obtained, a taxon not found in the “albardón” for two years. The germination index (GI) was estimated and the morphological characteristics of the gametophytes and sporophytes were recorded. This is the first contribution to the knowledge of the spore banks in Argentina, in a protected area where several threats put at risk the survival of native species. The bases to implement methods of ex situ and in situ conservation of native ferns are provided.

Resumen La recuperación de esporas del suelo es una estrategia para reforzar poblaciones en disminución o desaparecidas de los ambientes naturales. En este trabajo se analizaron 25 muestras de tierra extraídas de un parche de selva en galería en un albardón de la Reserva Punta Lara, Buenos Aires. Las muestras fueron distribuidas en 50 cápsulas de Petri, 25 expuestas a temperatura y luz controladas y otras 25 mantenidas en oscuridad. Para contribuir a la identificación de los gametofitos y esporofitos se cultivaron in vitro esporas de las especies del lugar. En 18 meses de ensayo se observó la aparición de gametofitos y esporofitos, en mayor proporción los pertenecientes a una especie dominante en la comunidad: Doryopteris concolor. Se obtuvieron además numerosos gametofitos y esporofitos de Gastoniella chaerophylla, un taxón no encontrado en el albardón desde hace dos años. Se estimó el índice de germinación (IG) y se registraron las características morfológicas de los gametofitos y esporofitos. Esta es la primera contribución al conocimiento de los bancos de esporas en Argentina, en un área protegida donde diversas amenazas ponen en riesgo la supervivencia de especies nativas. Se brindan las bases para implementar métodos de conservación ex situ e in situ de los helechos nativos.

The aim of this work was to evaluate the in vitro effect of the biofumigation with Brassica juncea L. Czerniak and Sinapis alba L. on the growth of Trichoderma spp. and Azospirillum brasilense Tarrand, Krieg et Döbereiner. Five doses (5, 15, 25, 35 and 55 g) of triturated plant material from B. juncea and S. alba were placed separately in plastic containers. Petri dishes with culture medium inoculated with Trichoderma spp. or A. brasilense, were placed on top of the plant material. The plastic containers were then covered and incubated in darkness for 7 days at 25±2ºC (Trichoderma spp.) and 31±2ºC (A. brasilense). After that, the diameter of the colonies of Trichoderma spp. was measured, and the number of colony forming units of A. brasilense was counted. The results indicated that: i) fungistatic effect of B. juncea and S. alba was not observed on Trichoderma spp. at any doses; ii) B. juncea inhibited colony growth of A. brasilense at doses of 15 g or higher, with an increasing inhibition as the biofumigant dose increased; iii) S. alba did not inhibit colony growth of A. brasilense at any doses. These in vitro results suggest that the technique of biocontrol with the antagonist fungus Trichoderma spp. can be compatible with biofumigation with B. juncea and S. alba. Also, A. brasilense can only be compatible with biofumigation with S. alba and with low doses of B. juncea.

El objetivo de este trabajo fue evaluar el efecto in vitro de la biofumigación con Brassica juncea L. Czerniak y Sinapis alba L. sobre el crecimiento de Trichoderma spp. y Azospirillum brasilense Tarrand, Krieg et Döbereiner. Se trituraron plantas de B. juncea y S. alba y se colocaron, por separado, en recipientes de plástico en dosis de 5, 15, 25, 35 y 55 g. Sobre el material triturado se apoyaron cajas Petri que contenían medio de cultivo inoculado con Trichoderma spp. o A. brasilense. Los recipientes de plástico se taparon e incubaron en oscuridad durante siete días, a 25±2ºC (Trichoderma spp.) y a 31±2ºC (A. brasilense). Finalizado ese periodo, se midió el diámetro de las colonias de Trichoderma spp. y se recontó el número de unidades formadoras de colonias de A. brasilense. Los resultados que se obtuvieron, in vitro, son los siguientes: i) no se observó efecto fungistático de B. juncea y de S. alba sobre Trichoderma spp. en ninguna de las dosis; ii) B. juncea inhibió el crecimiento de las colonias de A. brasilense con dosis de 15 g o superiores, con un aumento de la inhibición a medida que se incrementó la dosis del biofumigante; iii) S. alba no inhibió el crecimiento de las colonias de A. brasilense en ninguna de las dosis. Estos resultados sugieren que la técnica de biocontrol con el hongo antagonista Trichoderma spp. sería compatible con la biofumigación con B. juncea y S. alba. Además, A. brasilense solo sería compatible con la biofumigación con S. alba y con dosis bajas de B. juncea.

The aims of this work were: to determine feasibility of the combination of two biological control methods: application of antagonistic fungus Trichoderma spp. and biofumigation with the aerial part of Brassica juncea in the end of fruiting stage; to evaluate their effect on the growth of the pathogen Fusarium graminearum. Two doses (5 and 10 g) of triturated plant material from B. juncea were placed in plastic recipients. Petri dishes with potato glucose agar medium 2% and a disc inoculated with F. graminearum, or Trichoderma spp. or both fungi, were placed on top of the plant material. Plastic recipients were then closed and incubated at 25±2°C in darkness for 7 days. After that, the diameter of the colonies was measured. The results indicated that: i) when Trichoderma spp. and F. graminearum were biofumigated separately, fungistatic effect was not observed, ii) without biofumigant, Trichoderma spp. significantly inhibited growth of F. graminearum colonies, iii) the combination of Trichoderma spp. and the biofumigation with B. juncea showed synergic effect on growth control of F. graminearum. These in vitro results suggest that the growth of Trichoderma spp. And its potential biocontrol effect of F. graminearum, are not affected by biofumigation with B. juncea. Also, the combination of Trichoderma spp. and biofumigation with B. juncea, would have synergic effect on growth control of F. graminearum.

Los objetivos de este trabajo fueron: determinar la factibilidad de la utilización combinada de dos métodos de control biológico: la aplicación del hongo antagonista Trichoderma spp. y la biofumigación con la parte aérea de Brassica juncea en el estadio de fin de fructificación; evaluar su efecto sobre el crecimiento del patógeno Fusarium graminearum. Se trituraron plantas de B. juncea y se colocaron en recipientes de plástico en dosis de 5 y 10 g. Sobre el material triturado se apoyó una caja de Petri con agar papa glucosado al 2%, que contenía un disco con micelio de F. graminearum o Trichoderma spp. o ambos hongos. Los recipientes de plástico se cerraron e incubaron a 25±2°C en oscuridad durante 7 días. Finalizado este período, se midió el diámetro de las colonias. Se obtuvieron los siguientes resultados: i) cuando se biofumigaron por separado, no se observó efecto fungistático de B. juncea sobre Trichoderma spp. ni sobre F. graminearum; ii) en ausencia del biofumigante, Trichoderma spp. inhibió significativamente el crecimiento de las colonias de F. graminearum, iii) la combinación de Trichoderma spp. y la biofumigación con B. juncea mostró un efecto sinérgico sobre el control del crecimiento miceliar de F. graminearum. Los resultados in vitro sugieren que el crecimiento de Trichoderma spp. y su potencial efecto de biocontrol sobre F. graminearum, no son afectados por la biofumigación con B. juncea. La utilización combinada de Trichoderma spp. y la biofumigación con B. juncea, tendría un efecto sinérgico sobre el control del crecimiento de F. graminearum.

A doença de Whipple (DW) é infecção sistémica rara causada pelo Tropheryma whippelii. Cerca de 40% dos doentes apresentam envolvimento neurológico, seja como manifestação inicial da doença, seja durante o seu curso. Apresentamos o caso de um homem de 45 anos com doença de DW com episódios iniciais, persistentes e irresistíveis de sonolência durante a actividade diurna. O doente era positivo para o HLA-DQB1*0602 (marcador genético de narcolepsia). A suspeita do diagnóstico de DW foi levantada com base na clínica e RM e confirmada por estudo imunocitoquímico do material de biópsia jejunal. Quarenta meses mais tarde, todas as manifestações clínicas melhoraram, os episódios narcolépticos desapareceram, e a RM e o LCR normalizaram. Os estudos neurofisiológicos seriados do sono revelaram alterações persistentes caracterizadas por fragmentação do sono, escassez de ondas lentas e sono REM. A perturbação do circuito da hipocretina na região hipotálamo-diencefálica, causada pela infecção, foi a causa provável da hipersónia num doente geneticamente susceptível. A DW deve ser incluída nas causas de hipersónia secundária.

Whipple disease (WD) is a rare systemic infection caused by Tropheryma whippelii. Neurological involvement has been recognised in 40% of patients, either as initial manifestations or during the course of the disease. We report on a 45 years-old man with WD with initial, persistent and irresistible episodes of daytime somnolence. The patient was HLA-DQB1*0602 positive (genetic marker for narcolepsy). WD diagnosis was suspected on clinical and MRI basis and confirmed by histological and immunohistochemical study of duodenal biopsy. Forty months later all clinical features improved, narcoleptic-like episodes disappeared and cerebral MRI and CSF normalised. Longitudinal neurophysiological studies revealed persistent sleep pattern abnormalities with sleep fragmentation, paucity of slow wave and of REM sleep. The disruption of the hypocretin circuitry in the hypothalamic - diencephalic region triggered by the infection was the probable cause of the hypersomnia and narcopleptic symptoms. WD should be added to the list of causes of secondary hypersomnia.