Romina Gazis - Academia.edu (original) (raw)
Papers by Romina Gazis
Mycologia, Jan 6, 2015
Trichoderma harzianum is known as a cosmopolitan, ubiquitous species associated with a wide varie... more Trichoderma harzianum is known as a cosmopolitan, ubiquitous species associated with a wide variety of substrates. It is possibly the most commonly used name in agricultural applications involving Trichoderma, including biological control of plant diseases. While various studies have suggested that T. harzianum is a species complex, only a few cryptic species are named. In the present study the taxonomy of the T. harzianum species complex is revised to include at least 14 species. Previously named species included in the complex are T. guizhouense, T. harzianum, and T. inhamatum. Two new combinations are proposed, T. lentiforme and T. lixii. Nine species are described as new, T. afarasin, T. afroharzianum, T. atrobrunneum, T. camerunense, T. endophyticum, T. neotropicale, T. pyramidale, T. rifaii and T. simmonsii. We isolated Trichoderma cultures from four commercial biocontrol products reported to contain T. harzianum. None of the biocontrol strains were identified as T. harzianum ...
Mycologia, Jan 8, 2015
Research on fungal endophytes has expanded dramatically in recent years, but little is known abou... more Research on fungal endophytes has expanded dramatically in recent years, but little is known about the diversity and ecological roles of endophytic basidiomycetes. Here we report the analysis of 310 basidiomycetous endophytes isolated from wild and planted populations of the rubber tree genus, Hevea. Species accumulation curves were nonasymptotic, as in the majority of endophyte surveys, indicating that more sampling is needed to recover the true diversity of the community. One hundred eighteen OTUs were delimited, representing nine orders of Basidiomycota (Agaricales, Atheliales, Auriculariales, Cantharellales, Hymenochaetales, Polyporales, Russulales, Septobasidiales, Tremellales). The diversity of basidiomycetous endophytes found inhabiting wild populations of Hevea was comparable to that present in plantations. However, when samples were segregated by tissue type, sapwood of wild populations was found to contain a higher number of species than sapwood of planted trees. Seventy-f...
Reconstructing the phylogenetic relationships that unite all lineages (the tree of life) is a gra... more Reconstructing the phylogenetic relationships that unite all lineages (the tree of life) is a grand challenge. The paucity of homologous character data across disparately related lineages currently renders direct phylogenetic inference untenable. To reconstruct a comprehensive tree of life we therefore synthesized published phylogenies, together with taxonomic classifications for taxa never incorporated into a phylogeny. We present a draft tree containing 2.3 million tips -- the Open Tree of Life. Realization of this tree required the assembly of two additional community resources: 1) a novel comprehensive global reference taxonomy; and 2) a database of published phylogenetic trees mapped to this taxonomy. Our open source framework facilitates community comment and contribution, enabling the tree to be continuously updated when new phylogenetic and taxonomic data become digitally available. While data coverage and phylogenetic conflict across the Open Tree of Life illuminate gaps in...
The main objectives of this dissertation project were to characterize and compare the fungal endo... more The main objectives of this dissertation project were to characterize and compare the fungal endophytic communities associated with rubber trees (Hevea brasiliensis) distributed in wild habitats and under plantations. This study recovered an extensive number of isolates ( ...
Fungal Ecology, 2011
It has been hypothesized that endophytic fungi originate from local environmental sources, and en... more It has been hypothesized that endophytic fungi originate from local environmental sources, and endophyte identity and composition can be predicted based on surrounding ex planta fungi. As part of a pilot study to characterize endophytes and ex planta fungi (eg ...
Molecular Phylogenetics and Evolution, 2012
Through a culture-based survey of living sapwood and leaves of rubber trees (Hevea spp.) in remot... more Through a culture-based survey of living sapwood and leaves of rubber trees (Hevea spp.) in remote forests of Peru, we discovered a new major lineage of Ascomycota, equivalent to a class rank. Multilocus phylogenetic analyses reveal that this new lineage originated during the radiation of the 'Leotiomyceta', which resulted not only in the evolution of the Arthoniomycetes, Dothideomycetes, Eurotiomycetes, Geoglossomycetes, Lecanoromycetes, Leotiomycetes, Lichinomycetes, and Sordariomycetes, but also of the majority of hyperdiverse foliar endophytes. Because its origin is nested within this major burst of fungal diversification, we could not recover strong support for its phylogenetic relationship within the 'Leotiomyceta'. Congruent with their long phylogenetic history and distinctive preference for growing in sapwood, this new lineage displays unique morphological, physiological, and ecological traits relative to known endophytes and currently described members of the 'Leotiomyceta'. In marked contrast to many foliar endophytes, the strains we isolated fail to degrade cellulose and lignin in vitro. Discovery of the new class, herein named Xylonomycetes and originally mis-identified by ITSrDNA sequencing alone, highlights the importance of inventorying tropical endophytes from unexplored regions, using multilocus data sets to infer the phylogenetic placement of unknown strains, and the need to sample diverse plant tissues using traditional methods to enhance efforts to discover the evolutionary, taxonomic, and functional diversity of symbiotrophic fungi.
Fungal Ecology, 2011
... Measurements of continuous characters such as length and width were made using Scion Image so... more ... Measurements of continuous characters such as length and width were made using Scion Image software beta version 4.0.2 (Scion Corporation, Frederick, Maryland, USA). Continuous measurements were based on at least 30 measured units. ...
Fungal Ecology, 2010
... No cure exists for SALB and chemical fungicides have largely failed ( [Lieberei et al., 1988]... more ... No cure exists for SALB and chemical fungicides have largely failed ( [Lieberei et al., 1988] , [Priyadarshan and Goncalves, 2003] , [Le Guen et al ... gene was amplified: translation elongation factor 1α (tef1) using the primers EF-728 (Carbone & Kohn 1999) and EF2 (Jacobs et al. ...
Mycologia, Jan 6, 2015
Trichoderma harzianum is known as a cosmopolitan, ubiquitous species associated with a wide varie... more Trichoderma harzianum is known as a cosmopolitan, ubiquitous species associated with a wide variety of substrates. It is possibly the most commonly used name in agricultural applications involving Trichoderma, including biological control of plant diseases. While various studies have suggested that T. harzianum is a species complex, only a few cryptic species are named. In the present study the taxonomy of the T. harzianum species complex is revised to include at least 14 species. Previously named species included in the complex are T. guizhouense, T. harzianum, and T. inhamatum. Two new combinations are proposed, T. lentiforme and T. lixii. Nine species are described as new, T. afarasin, T. afroharzianum, T. atrobrunneum, T. camerunense, T. endophyticum, T. neotropicale, T. pyramidale, T. rifaii and T. simmonsii. We isolated Trichoderma cultures from four commercial biocontrol products reported to contain T. harzianum. None of the biocontrol strains were identified as T. harzianum ...
Mycologia, Jan 8, 2015
Research on fungal endophytes has expanded dramatically in recent years, but little is known abou... more Research on fungal endophytes has expanded dramatically in recent years, but little is known about the diversity and ecological roles of endophytic basidiomycetes. Here we report the analysis of 310 basidiomycetous endophytes isolated from wild and planted populations of the rubber tree genus, Hevea. Species accumulation curves were nonasymptotic, as in the majority of endophyte surveys, indicating that more sampling is needed to recover the true diversity of the community. One hundred eighteen OTUs were delimited, representing nine orders of Basidiomycota (Agaricales, Atheliales, Auriculariales, Cantharellales, Hymenochaetales, Polyporales, Russulales, Septobasidiales, Tremellales). The diversity of basidiomycetous endophytes found inhabiting wild populations of Hevea was comparable to that present in plantations. However, when samples were segregated by tissue type, sapwood of wild populations was found to contain a higher number of species than sapwood of planted trees. Seventy-f...
Reconstructing the phylogenetic relationships that unite all lineages (the tree of life) is a gra... more Reconstructing the phylogenetic relationships that unite all lineages (the tree of life) is a grand challenge. The paucity of homologous character data across disparately related lineages currently renders direct phylogenetic inference untenable. To reconstruct a comprehensive tree of life we therefore synthesized published phylogenies, together with taxonomic classifications for taxa never incorporated into a phylogeny. We present a draft tree containing 2.3 million tips -- the Open Tree of Life. Realization of this tree required the assembly of two additional community resources: 1) a novel comprehensive global reference taxonomy; and 2) a database of published phylogenetic trees mapped to this taxonomy. Our open source framework facilitates community comment and contribution, enabling the tree to be continuously updated when new phylogenetic and taxonomic data become digitally available. While data coverage and phylogenetic conflict across the Open Tree of Life illuminate gaps in...
The main objectives of this dissertation project were to characterize and compare the fungal endo... more The main objectives of this dissertation project were to characterize and compare the fungal endophytic communities associated with rubber trees (Hevea brasiliensis) distributed in wild habitats and under plantations. This study recovered an extensive number of isolates ( ...
Fungal Ecology, 2011
It has been hypothesized that endophytic fungi originate from local environmental sources, and en... more It has been hypothesized that endophytic fungi originate from local environmental sources, and endophyte identity and composition can be predicted based on surrounding ex planta fungi. As part of a pilot study to characterize endophytes and ex planta fungi (eg ...
Molecular Phylogenetics and Evolution, 2012
Through a culture-based survey of living sapwood and leaves of rubber trees (Hevea spp.) in remot... more Through a culture-based survey of living sapwood and leaves of rubber trees (Hevea spp.) in remote forests of Peru, we discovered a new major lineage of Ascomycota, equivalent to a class rank. Multilocus phylogenetic analyses reveal that this new lineage originated during the radiation of the 'Leotiomyceta', which resulted not only in the evolution of the Arthoniomycetes, Dothideomycetes, Eurotiomycetes, Geoglossomycetes, Lecanoromycetes, Leotiomycetes, Lichinomycetes, and Sordariomycetes, but also of the majority of hyperdiverse foliar endophytes. Because its origin is nested within this major burst of fungal diversification, we could not recover strong support for its phylogenetic relationship within the 'Leotiomyceta'. Congruent with their long phylogenetic history and distinctive preference for growing in sapwood, this new lineage displays unique morphological, physiological, and ecological traits relative to known endophytes and currently described members of the 'Leotiomyceta'. In marked contrast to many foliar endophytes, the strains we isolated fail to degrade cellulose and lignin in vitro. Discovery of the new class, herein named Xylonomycetes and originally mis-identified by ITSrDNA sequencing alone, highlights the importance of inventorying tropical endophytes from unexplored regions, using multilocus data sets to infer the phylogenetic placement of unknown strains, and the need to sample diverse plant tissues using traditional methods to enhance efforts to discover the evolutionary, taxonomic, and functional diversity of symbiotrophic fungi.
Fungal Ecology, 2011
... Measurements of continuous characters such as length and width were made using Scion Image so... more ... Measurements of continuous characters such as length and width were made using Scion Image software beta version 4.0.2 (Scion Corporation, Frederick, Maryland, USA). Continuous measurements were based on at least 30 measured units. ...
Fungal Ecology, 2010
... No cure exists for SALB and chemical fungicides have largely failed ( [Lieberei et al., 1988]... more ... No cure exists for SALB and chemical fungicides have largely failed ( [Lieberei et al., 1988] , [Priyadarshan and Goncalves, 2003] , [Le Guen et al ... gene was amplified: translation elongation factor 1α (tef1) using the primers EF-728 (Carbone & Kohn 1999) and EF2 (Jacobs et al. ...