Rapid and Easy Modified Plate-based Screening Methods for Quantitative and Qualitative Detection of Protease Production by Fungi

Proteases constitute a significant part of cell wall-degrading enzymes (CWDEs) produced by fungal biocontrol agents and particularly crucial in mycoparasitism of fungal phytopathogens. Plate-based screening methods are routinely used for screening protease-producing microorganisms including fungi. Skim milk agar (SMA) is one of the most popular media for the detection of protease producing bacteria. However, SMA is not efficient to test fast growing fungi, because it does not give an estimation of the actual amount of secreted protease produced by fungal inocula. In the current study, the efficacy of two modified plate-screening methods, including split-SMA (SSMA) and minimal medium supplemented with skim milk (MSMW) was assessed for detection of protease production by three representative fungal strains including Trichoderma longibrachiatum strain N, Beauveria bassiana strain B and Purpureocillium lilacinum strain PL. Protease production was revealed on the three tested media by the three strains. However, the halo diameter of the fungal strains (a proxy for protease production) was the smallest on SMA. Furthermore, protease production could not be detected for T. longibrachiatum strain N on SMA due to its fast growth; while it showed the highest protease activity on both modified media compared with the other strains. According to the result of this study, the SSMA medium is an easy and more accurate method compared with the two other different methods as it displays the actual amount of protease produced by fungal strains and therefore this method is recommended for quantitative and qualitative detection of protease production by slow and fast growing fungi

Is morphology in Cercospora a reliable reflection of generic affinity?

Cercospora (Mycosphaerellaceae) is a large genus of fungi comprising many important plant pathogens. In recent years DNA-based studies have revealed multiple genera of cercosporoid fungi being poly- and paraphyletic. Among these genera, the genus Cercospora has always been perceived as monophyletic. In the present study, phylogenetic inferences based on partial gene sequences of the LSU, ITS, ACT, TEF1-α and HIS loci, elucidated a cercospora-like taxon from Ammi majus to cluster in a clade apart from Cercospora s. str. In spite of numerous Cercospora spp. presently known from their DNA sequence data, this collection represents the first concrete evidence to the fact that the morphological characters previously attributed to Cercospora s. str. evolved more than once in the Mycosphaerellaceae. The genus Neocercospora is subsequently introduced to accommodate the Iranian taxon occurring on A. majus. Further collections on other hosts and from different continents are now required to establish the prevalence and relative importance of species of Neocercospora.Laboratory of Evolutionary Phytopathology, CBS-KNAW Fungal Biodiversity Centre, the Research Deputy of the University of Tabriz and the Studienstiftung für mykologische Systematik und Ökologie.http://www.mapress.com/phytotaxahb201

Application of the consolidated species concept to Cercospora spp. from Iran

The genus Cercospora includes many important plant pathogenic fungi associated with leaf spot diseases on a wide range of hosts. The mainland of Iran covers various climatic regions with a great biodiversity of vascular plants, and a correspondingly high diversity of cercosporoid fungi. However, most of the cercosporoid species found to date have been identified on the basis of morphological characteristics and there are no cultures that support these identifications. In this study the Consolidated Species Concept was applied to differentiate Cercospora species collected from Iran. A total of 161 Cercospora isolates recovered from 74 host species in northern Iran were studied by molecular phylogenetic analysis. Our results revealed a rich diversity of Cercospora species in northern Iran. Twenty species were identified based on sequence data of five genomic loci (ITS, TEF1-α, actin, calmodulin and histone H3), host, cultural and morphological data. Six novel species, viz. C. convolvulicola, C. conyzae-canadensis, C. cylindracea, C. iranica, C. pseudochenopodii and C. sorghicola, are introduced. The most common taxon was Cercospora cf. flagellaris, which remains an unresolved species complex with a wide host range. New hosts were recorded for previously known Cercospora species, including C. apii, C. armoraciae, C. beticola, C. cf. richardiicola, C. rumicis, Cercospora sp. G and C. zebrina.The Research Deputy of the University of Tabriz, the Studienstiftung für mykologische Systematik und Ökologie and the CBSKNAW Fungal Biodiversity Centre.http://www.ingentaconnect.com/content/nhn/pimjam201

Application of the consolidated species concept to Cercospora spp. from Iran

The genus Cercospora includes many important plant pathogenic fungi associated with leaf spot diseases on a wide range of hosts. The mainland of Iran covers various climatic regions with a great biodiversity of vascular plants, and a correspondingly high diversity of cercosporoid fungi. However, most of the cercosporoid species found to date have been identified on the basis of morphological characteristics and there are no cultures that support these identifications. In this study the Consolidated Species Concept was applied to differentiate Cercospora species collected from Iran. A total of 161 Cercospora isolates recovered from 74 host species in northern Iran were studied by molecular phylogenetic analysis. Our results revealed a rich diversity of Cercospora species in northern Iran. Twenty species were identified based on sequence data of five genomic loci (ITS, TEF1-α, actin, calmodulin and histone H3), host, cultural and morphological data. Six novel species, viz. C. convolvulicola, C. conyzae-canadensis, C. cylindracea, C. iranica, C. pseudochenopodii and C. sorghicola, are introduced. The most common taxon was Cercospora cf. flagellaris, which remains an unresolved species complex with a wide host range. New hosts were recorded for previously known Cercospora species, including C. apii, C. armoraciae, C. beticola, C. cf. richardiicola, C. rumicis, Cercospora sp. G and C. zebrina.The Research Deputy of the University of Tabriz, the Studienstiftung für mykologische Systematik und Ökologie and the CBSKNAW Fungal Biodiversity Centre.http://www.ingentaconnect.com/content/nhn/pimjam201

Pseudovirgaria, a fungicolous hyphomycete genus

The genus Pseudovirgaria, based on P. hyperparasitica, was recently introduced for a mycoparasite of rust sori of various species of Frommeëlla, Pucciniastrum and Phragmidium in Korea. In the present study, an older name introduced by Saccardo based on European material, Rhinotrichum griseum, is shown to resemble P. hyperparasitica. Morphological study and ITS barcodes from fresh collections of R. griseum from Austria on uredinia and telia of Phragmidium bulbosum on Rubus spp. reveal that it is distinct from P. hyperparasitica. The status of the genus Rhinotrichum, introduced for a fungus occurring on dry wood, remains unclear. Pseudovirgaria grisea comb. nov. is therefore proposed for the mycoparasite occurring on rust fungi in Europe, and an epitype is designated from the recent collections

Racoleus, a new genus of sterile filamentous lichen-forming fungi from the tropics, with observations on the nomenclature and typification of Cystocoleus and Racodium

Racoleus trichophorus gen. sp. nov. is described for a tropical sterile filamentous lichenized fungus which overgrows various crustose lichens on bark. It shares some features with Cystocoleus and Racodium, but is unique in having non-lichenized long lateral spines. The genus, which is known from China, the Ivory Coast, and Peru, is of uncertain systematic position; on the basis of morphological similarities, however, it may be referred to “? Capnodiales (incertae sedis)” ad interim. In addition, the nomenclature and typification of the monotypic genera Cystocoleus and Racodium are reviewed, and lectotypes selected for the type of each. The available information on the ecology and distribution of these two genera is also summarized, and scanning electron micrographs (SEM) of all three species are presented for the first time

Desafíos políticos de los países de inmigración

13 págs.-- Publicado en "Confluencia XXI. Revista de Pensamiento Político" (México), nº 3 (Oct-Dic 2008) bajo el título monográfico "Migrantes: ¿Por qué se van? ¿Por qué se quedan?".Las migraciones, una práctica tan antigua como la propia condición humana, se han convertido en un factor estructural de primer orden, en uno de los macrofenómenos más definitorios de nuestra época y en un complejo reto para las sociedades contemporáneas. En prácticamente todos los países del mundo, todo lo que concierne a este complejo fenómeno ocupa un lugar destacado en la agenda política. La gestión, el control y la integración de los movimientos internacionales de personas se presentan como un policy field de creciente y prioritaria relevancia. No se trata, sin embargo, de una cuestión de mera moda: el número de países implicados de manera significativa en las migraciones internacionales ha aumentado considerablemente, hasta el punto de que resulta realmente difícil encontrar algún Estado que no sea bien un país de inmigración, bien un país de emigración o bien ambas cosas a la vez, cuando no al menos un país de tránsito. No ha de extrañar entonces que la mayoría de los gobiernos haya tomado conciencia de la necesidad de ofrecer una respuesta en términos legales e institucionales a un fenómeno de carácter permanente que puede llegar a alterar la estructura demográfica, social, cultural, económica y laboral de un país. Dada la complejidad de la cuestión, y por cuestiones de economía argumentativa, aquí se abordará de manera fundamental desde la perspectiva de los países receptores, que, por lo demás, es también la adoptada en forma habitual por los países europeos que registran mayor inmigración. Sin embargo, el fenómeno migratorio es fundamentalmente transnacional y tiene fehacientes repercusiones en los países de emigración.Peer reviewe