12 research outputs found
Patogenicidad de hongos asociados a plantas de fresa (Fragaria ananassa) y descripción ultraestructural del patosistema
Introducción. La fresa es importante en Costa Rica por su alta demanda como fruta fresca y para elaboración de mermeladas. En 2015 empezaron reportes de muerte de plantas, presumiblemente, asociada a complejos de hongos habitantes del suelo. Los síntomas eran enrojecimiento y necrosis de hojas, coronas y raíces; luego, el desplome de las plantas. Con pérdidas hasta del 90% en plantaciones nuevas. Objetivo. Determinar la patogenicidad de hongos asociados a plantas de fresa enfermas y describir la micro morfología del patosistema. Materiales y métodos. Se colectaron plantas enfermas variedad Festival, y se realizaron aislamientos a partir de corona y raíz. Se clasificaron los morfotipos recuperados, se eligieron tres para secuenciación del espaciador interno transcrito del ADN nuclear ribosomal (nrDNA ITS por sus siglas en inglés) y ejecución de los Postulados de Koch, con 3,5 x 105 conidios/ml inoculados en gránulos de alfalfa. Las plantas se mantuvieron 19 semanas en ambiente protegido. Luego, se realizó el reaislamiento y la secuenciación de los hongos inoculados, y se describió el patosistema, por medio de microscopía electrónica de barrido. Resultados. Se obtuvieron diez aislamientos de hongos de corona y 22 de raíz, que se clasificaron en nueve morfotipos. Se eligieron tres, que, de acuerdo con el ITS, se ubicaron en las unidades taxonómicas operativas Fusarium oxysporum, Neonectria/Dactylonectria y Sydowia polyspora. Se registró 100% de incidencia en todas las plantas inoculadas y los síntomas coincidieron con los de campo, mientras que, el testigo permaneció sano. Los porcentajes de similitud de las secuencias de ITS de los hongos aislados de plantas enfermas, provenientes de campo y de los hongos recuperados de la prueba de patogenicidad, fueron > 99%. A nivel ultraestructural se observó que las raíces pierden la epidermis y son colonizadas por los hongos. Conclusión. Los hongos inoculados fueron patogénicos a plantas de fresa variedad Festival, tuvieron la capacidad de dañar la epidermis radical y multiplicarse internamente.Pathogenicity of fungi associated with strawberry plants (Fragaria ananassa) and ultrastructural description of the pathosystem. Introduction. Strawberries are important in Costa Rica due to their high demand as fresh fruit and for making jams. In 2015, reports of plant death began, presumably associated with soil-dwelling fungal complexes. The symptoms were redness and necrosis of leaves, crowns, and roots, then the collapse of the plants. With losses of up to 90% in new plantations. Objective. To determine the pathogenicity of fungi associated with diseased strawberry plants and to describe the micromorphology of the pathosystem. Materials and methods. Diseased Festival variety plants were collected, and isolations were made from crown and root. The recovered morphotypes were classified, three were chosen for sequencing of the internal transcribed spacer of nuclear ribosomal DNA (nrDNA ITS) and execution of Koch’s Postulates, with 3.5 x 105conidia/ml inoculated in alfalfa granules. The plants were kept for 19 weeks in a protected environment. Then, reisolation and sequencing of the inoculated fungi was performed, and the pathosystem was described by means of scanning electron microscopy. Results. Ten isolates of crown and 22 root fungi were obtained, which were classified into 9 morphotypes. Three were chosen, which, according to the ITS, were in the operational taxonomic units Fusarium oxysporum, Neonectria/Dactylonectria and Sydowia polyspora. The 100% incidence was recorded in all the inoculated plants and the symptoms coincided with those in the field, while the control remained healthy. The similarity percentages of the ITS sequences of the fungi isolated from diseased plants, from the field, and of the fungi recovered from the pathogenicity test, were > 99%. At the ultrastructural level, it was observed that the roots lose the epidermis and are colonized by fungi. Conclusion. The inoculated fungi were pathogenic to Festival variety strawberry plants, they had the ability to damage the root epidermis and multiply internallyUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Estructuras Microscópicas (CIEMIC)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones en Productos Naturales (CIPRONA)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí
A microfungus from Costa Rica: Ticosynnema gen. nov.
Ticosynnema carranzae gen. & sp. nov., a new microfungus collected on the
twig of an unidentified plant, is described and illustrated. It is distinguished by synnematous
determinate conidiomata, monoblastic integrated determinate conidiogenous cells, and solitary,
3–4-septate, oblong, cylindrical to vermiform, brown conidia that secede rhexolytically.UCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de AgronomíaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro de Investigación en Protección de Cultivos (CIPROC)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí
Phylogenetics and taxonomy of Telimenaceae (Phyllachorales) from Central America
Since the circumscription of the genera Phyllachora and Telimena has been emended, several neotropical nongraminicolous
species of Phyllachora have been transferred to Telimena, and several species of Telimena have been
newly described. In order to better understand the species diversity and taxonomy of neotropical tar spot fungi,
symptomatic leaves of non-graminicolous hosts of Trichilia sp. (Meliaceae) and Acalypha spp. (Euphorbiaceae) were
collected in Costa Rica and Panama. Telimena trichiliae is newly described from Panama and Phyllachora
acalyphae, Ph. Pichinchae, and Ph. balansae are newly combined into Telimena. Detailed morphological descriptions
and illustrations are provided. New synonyms and records of Telimena are also presented, together with new
morphological, host plant, and molecular data. We also present a revision and a dichotomous key for neotropical tar
spot fungi on the host family Meliaceae.Deutscher Akademischer Austauschdienst/[]/DAAD/AlemaniaUniversidad de Costa Rica/[111-B8-284]/UCR/Costa RicaDeutsche Forschungsgemeinschaft/[]/DFG/AlemaniaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí
Systematics, taxonomy, and distribution of Myriogenospora G.F. Atk. (Clavicipitaceae, Hypocreales, Ascomycota)
Based on new specimens of Myriogenospora spp. from Costa Rica and Panama, we present morphological analyses,
systematic conclusions, additions to host ranges, and geographical distribution data for the two species currently classified
in this genus. Myriogenospora atramentosa (Berk. & M.A. Curtis) Diehl differs from Myriogenospora linearis
(Rehm) J.F. White & Glenn in the ascus and part-spore morphology, a different position in the molecular phylogeny,
and the host range. We conclude that the two species are not congeneric and propose that M. linearis should be called
Balansia linearis (Rehm) Diehl.Universidad de Costa Rica/[]/UCR/Costa RicaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí
Contribution to the phylogeny and a new species of Coccodiella (Phyllachorales)
Coccodiella is a genus of plant-parasitic species in
the family Phyllachoraceae (Phyllachorales, Ascomycota),
i.e., tropical tar spot fungi. Members of the genus Coccodiella
are tropical in distribution and are host-specific, growing on
plant species belonging to nine host plant families. Most of
the known species occur on various genera and species of the
Melastomataceae in tropical America. In this study, we describe
the new species C. calatheae from Panama, growing on
Calathea crotalifera (Marantaceae). We obtained ITS, nrLSU,
and nrSSU sequence data from this new species and from other
freshly collected specimens of five species of Coccodiella on
members of Melastomataceae from Ecuador and Panama.
Phylogenetic analyses allowed us to confirm the placement of
Coccodiella within Phyllachoraceae, as well as the monophyly
of the genus. The phylogeny of representative species within
the family Phyllachoraceae, including Coccodiella spp.,
graminicolous species of Phyllachora and taxa with erumpent
to superficial stroma from several host families, suggests that
the genus Phyllachora might be polyphyletic. Furthermore, tar
spot fungi with superficial or erumpent perithecia seem to be
restricted to the family Phyllachoraceae, independently of the
host plant. We also discuss the biodiversity and host-plant patterns
of species of Coccodiella worldwide.Deutsche Forschungsgemeinschaft/[]/DFG/AlemaniaDeutscher Akademischer Austauschdienst/[]/DAAD/AlemaniaOficina de Asuntos Internacionales y Cooperación Externa/[]/OAICE-UCR/Costa RicaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí
Telimena (Telimenaceae, Phyllachorales) species on Neotropical host plants: New species, combinations and revision of species on Polygonaceae
In this investigation, we propose a new species in Telimena, T. bromeliae sp. nov. growing on bromeliads with a detailed description, illustrations, and molecular characterisation based on material collected in Costa Rica and Panama. Additionally, four species of Phyllachora occurring on non-graminicolous hosts are transferred into Telimena based on morphological and molecular data: T. amphibola comb. nov. on Inga spp. and T. tenuis comb. nov. on Bauhinia spp. (Fabaceae, Cercidiodeae); T. dominicana comb. nov. on Coccoloba spp.; and T. rubefaciens comb. nov. on Clethra spp. (Clethraceae). The species with newly combined names are redescribed and fully illustrated from type specimens and material recently collected in Costa Rica, Florida (USA) and Panama. Additionally, a revision of tropical tar spot fungi on host species belonging to the family Polygonaceae is provided, including a dichotomous key of known species and geographical distribution data.Universidad de Costa Rica/[111-B8-284]/UCR/Costa RicaMinisterio de Ambiente y Energía/[]/MINAE/Costa RicaAutoridad Nacional de Ambiente/[]/ANAM/PanamáDeutsche Forschungsgemeinschaft/[]/DFG/AlemaniaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de BiologíaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Biodiversidad y Ecología Tropical (CIBET
Taxonomy and phylogeny of the genus Ganoderma (Polyporales, Basidiomycota) in Costa Rica
Ganoderma species are well recognised by their significant role in the recycling of nutrients in ecosystems and by their production of secondary metabolites of medical and biotechnological importance. Ganoderma spp. are characterised by laccate and non-laccate, woody basidiocarps, polypore hymenophores and double-walled basidiospores generally with truncate apex. Despite the importance of this genus, its taxonomy is unclear and it includes several species’ complexes with few circumscribed species and incorrect geographic distributions. The aim of this work was to provide detailed morphological descriptions together with phylogenetic analyses using ITS sequences to confirm the presence of seven species of Ganoderma in Costa Rica: G. amazonense, G. applanatum s.l., G. australe, G. curtisii, G. ecuadorense, G. oerstedii and G. parvulum. This is the first study that integrates morphological and phylogenetic data of Ganoderma from Central America and a key of the neotropical species. Besides, the distribution range of G. curtisii, previously reported from North America and G. ecuadorense from South America, is expanded to Central America
New neotropical species of Phyllachorales based on molecular, morphological, and ecological data
Species of tropical tar spot fungi (Phyllachorales, Ascomycota) are obligate biotrophic plant
parasitic fungi associated with living leaves of a wide range of families of host plants, mainly in
tropical and subtropical regions. In this study, samples of tropical tar spot fungi were collected
in forests in Costa Rica and Panamá. To identify taxa, we used morphology and information on
host plants and combined multigene phylogeny of four genes: the large subunit nuclear
ribosomal DNA (28S rDNA), the small subunit nuclear ribosomal DNA (18S rDNA), the complete
internal transcribed spacer region of ribosomal DNA (nuc rDNA ITS1-5.8S-ITS2; ITS), and the
translation elongation factor 1-α (tef1). Here we propose one new species in the genus
Camarotella and eight new species in Telimena with their morphological descriptions, illustrations,
and sequence data. The newly described species are Camarotella licaniae on Licania
arborea (Chrysobalanaceae) and in the genus Telimena: T. billiae on Billia rosea (Sapindaceae),
T. drymoniae on Drymonia multiflora (Gesneriaceae), T. hydrangeae on Hydrangea sp.
(Hydrangeaceae), T. miravallensis on Symplocos panamensis (Symplocaceae), T. protii on
Protium sp. (Burseraceae), T. rinoreae on Rinorea sp. (Violaceae), T. semialarii on Semialarium
mexicanum (Celastraceae), and T. triseptata on Tapirira mexicana (Anacardiaceae). The new name
Telimena nitens on Schlegelia brachyanta (Schlegeliaceae) is presented and 10 species of
Phyllachora are transferred to Telimena, leading to the new combinations T. canarii, T. galavisii,
T. insueta, T. ruelliae, T. scutiformis, T. serjaniicola, T. spicatae, T. subrepens, T. symploci, and T.
symplocicola. Additionally, revisions of tar spot fungi on host families Burseraceae, Sapindaceae,
and Symplocaceae are provided, and four new synonyms are proposed.Deutsche Forschungsgemeinschaft/[]/DFG/AlemaniaDeutscher Akademischer Austauschdienst/[]/DAAD/AlemaniaOficina de Asuntos Internacionales y Cooperación Externa/[]/OAICE-UCR/Costa RicaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí
Phylogeny of the order Phyllachorales (Ascomycota, Sordariomycetes): among and within order relationships based on five molecular loci
The order Phyllachorales (Pezizomycotina, Ascomycota) is a group of biotrophic, obligate plant parasitic
fungi with a tropical distribution and high host specificity. Traditionally two families are recognised within this order:
Phyllachoraceae and Phaeochoraceae, based mostly on morphological and host characteristics. Currently, the
position of the order within the class Sordariomycetes is inconclusive, as well as the monophyly of the order, and
its internal phylogenetic structure. Here we present a phylogeny of the order Phyllachorales based on sequence
data of 29 species with a broad host range resulting from a wide geographical sampling. We inferred Maximum
Likelihood and Bayesian phylogenies from data of five DNA regions: nrLSU rDNA, nrSSU rDNA, ITS rDNA, and
the protein coding genes RPB2, and TEF1. We found that the order Phyllachorales is monophyletic and related
to members of the subclass Sordariomycetidae within Sordariomycetes. Within the order, members of the family
Phaeochoraceae form a monophyletic group, and the family Phyllachoraceae is split into two lineages. Maximum
Likelihood ancestral state reconstructions indicate that the ancestor of Phyllachorales had a monocotyledonous
host plant, immersed perithecia, and a black stroma. Alternative states of these characters evolved multiple times
independently within the order. Based on our results we redefine the family Phyllachoraceae and propose the new
family Telimenaceae with Telimena erythrinae as type species, resulting in three families in the order. Species of
Telimena spp. occur in several monocotyledonous and eudicotyledonous host plants except Poaceae, and generally
have enlarged black pseudostroma around the perithecia, a character not present in species of Phyllachoraceae.Deutsche Forschungsgemeinschaft/[]/DFG/AlemaniaDeutscher Akademischer Austauschdienst/[]/DAAD/AlemaniaOficina de Asuntos Internacionales y Cooperación Externa/[]/OAICE-UCR/Costa RicaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí