Ruvishika S Jayawardena | Mae Fah Luang University (original) (raw)

Papers by Ruvishika S Jayawardena

Metabolites

From the rice fermentation product of a new record fungus, Neohelicosporium griseum, two new poly... more From the rice fermentation product of a new record fungus, Neohelicosporium griseum, two new polyketides, neogrisphenol A (1) and neogrisphenol B (2), one new isochroman-1-one, (S)-6-hydroxy-7-methoxy-3,5-dimethylisochroman-1-one (3), and four known compounds (4–7) were isolated. Their structures were determined using 1D- and 2D-NMR, mass spectrometry, and chemical calculations. The C-3~C-2′ polymerization mode between the two α-naphthalenone derivative moieties is uncommon in compounds 1 and 2. Meanwhile, compounds 1–2 and 5 exhibited antibacterial activity against Bacillus subtilis, Clostridium perfringens, Staphylococcus aureus, and Staphylococcus aureus, with MIC values ranging between 16 and 31 µg/mL. In addition, compound 5 showed antifungal activity against Sclerotinia sclerotiorum and Phytophthora nicotianae var. nicotianae, with respective IC50 values of 88.14 ± 2.21 µg/mL and 52.36 ± 1.38 µg/mL. Compound 1 showed significant cytotoxicity against A2780, PC-3, and MBA-MD-231...

Journal of Fungi

Uromyces is the second-largest plant pathogenic rust genus, is responsible for numerous diseases,... more Uromyces is the second-largest plant pathogenic rust genus, is responsible for numerous diseases, and has major effects on both agricultural and non-agricultural plants. The genus is generally characterized by its unicellular teliospores that help to characterize it and distinguish it from another important rust genus, Puccinia. In this study, a global overview of the diversity and distribution of Uromyces is presented based on both online and offline resources. The information obtained was analyzed for numerical and graphical summaries to provide the diversity and distribution of the genus by country and continent. Besides this, broad taxonomical aspects, a brief life cycle, and other comparative aspects on diversity and distribution were also provided. In addition, a phylogenetic analysis based on the ITS and nLSU DNA sequence data available in GenBank and published literature was performed to examine the intergeneric relationships of Uromyces. The results obtained revealed that t...

Pathogens

Coffee is grown in more than 80 countries as a cash crop and consumed worldwide as a beverage and... more Coffee is grown in more than 80 countries as a cash crop and consumed worldwide as a beverage and food additive. It is susceptible to fungal infection during growth, processing and storage. Fungal infections, in particular, can seriously affect the quality of coffee and threaten human health. The data for this comprehensive review were collected from the United States Department of Agriculture, Agricultural Research Service (USDA ARS) website and published papers. This review lists the fungal species reported on coffee based on taxonomy, life mode, host, affected plant part and region. Five major fungal diseases and mycotoxin-producing species (post-harvest diseases of coffee) are also discussed. Furthermore, we address why coffee yield and quality are affected by fungi and propose methods to control fungal infections to increase coffee yield and improve quality. Endophytic fungi and their potential as biological control agents of coffee disease are also discussed.

A fungus was collected from a dead twig of Ulmus minor  Ulmus pumila in Southern European Russia... more A fungus was collected from a dead twig of Ulmus minor  Ulmus pumila in Southern European Russia. The phylogenetic analysis based on combined gene regions of Internal transcribed spacer (ITS), the large subunit of nuclear ribosomal RNA (LSU), beta-tubulin (TUB2) and the second-largest subunit of nuclear RNA polymerase II (RPB2) sequence dataset shows that species clusters within the genus Nothophoma. Morphological characteristics and phylogenetic results confirmed that the fungus is Nothophoma quercina. Since this is the first report of N. quercina from Ulmus, we report this species as a new host record from Ulmus minor × Ulmus pumila in Russia. A detailed description, colour photographs and a phylogenetic tree to show the placement of N. quercina are given.

Fungal Diversity, 2021

Scientific names are crucial for communicating knowledge concerning fungi and fungus-like organis... more Scientific names are crucial for communicating knowledge concerning fungi and fungus-like organisms. In plant pathology, they link information regarding biology, host range, distribution and potential risk to agriculture and food security. In the past, delimitation among pathogenic taxa was primarily based on morphological characteristics. Due to distinct species sharing overlapping characteristics, the morphological identification of species is often neither straightforward nor reliable. Hence, the phylogenetic species concept based on molecular phylogenetic reconstructions gained importance. The present opinion discusses what a fungal species is and how identification of species in plant pathology has changed over the past decades. In this context, host-specialization and species complexes are discussed. Furthermore, species concepts in plant pathology are examined using case studies from Bipolaris, Colletotrichum, Curvularia, Diaporthe, Diplodia, Meliola, Plasmopara, rust fungi and Trichoderma. Each entry contains a brief introduction to the genus, concepts used in species identification so far and the problems in describing a species followed by recommendations. The importance of correctly naming and identifying a species is addressed in the context of recent introductions, and we also discuss whether the introduction of new species in pathogenic genera has been overestimated. We also provide guidelines to be considered when introducing a new species in a plant pathogenic genus.

Asian Journal of Mycology, 2020

Fungal Diversity, 2020

This is the twelfth contribution to the Fungal Diversity Notes series on fungal taxonomy, based o... more This is the twelfth contribution to the Fungal Diversity Notes series on fungal taxonomy, based on materials collected from many countries which were examined and described using the methods of morphology, anatomy, and strain culture, combined with DNA sequence analyses. 110 taxa are described and illustrated, including five new genera, 92 new species, eight new combinations and other taxonomic contributions (one new sequenced species, one new host and three new records) which are accommodated in 40 families and 1 incertae sedis in Dothideomycetes. The new genera are Amyloceraceomyces, Catenuliconidia, Hansenopezia, Ionopezia and Magnopulchromyces. The new species are Amyloceraceomyces angustisporus, Amylocorticium ellipsosporum,

Asian Journal of Mycology, 2020

Asian Journal of Mycology, 2019

Fungal Diversity, 2019

This paper is the second in a series focused on providing a stable platform for the taxonomy of p... more This paper is the second in a series focused on providing a stable platform for the taxonomy of phytopathogenic fungi. It focuses on 25 phytopathogenic genera: Alternaria, Bipolaris, Boeremia, Botryosphaeria, Calonectria, Coniella, Corticiaceae, Curvularia, Elsinoe, Entyloma, Erythricium, Fomitiporia, Fulviformes, Laetisaria, Limonomyces, Neofabraea, Neofusicoccum, Phaeoacremonium, Phellinotus, Phyllosticta, Plenodomus, Pseudopyricularia, Tilletia, Venturia and Waitea, using recent molecular data, up to date names and the latest taxonomic insights. For each genus a taxonomic background, diversity aspects, species identification and classification based on molecular phylogeny and recommended genetic markers are provided. In this study, varieties of the genus Boeremia have been elevated to species level. Botryosphaeria, Bipolaris, Curvularia, Neofusicoccum and Phyllosticta that were included in the One Stop Shop 1 paper are provided with updated entries, as many new species have been introduced to these genera.

Metabolites

From the rice fermentation product of a new record fungus, Neohelicosporium griseum, two new poly... more From the rice fermentation product of a new record fungus, Neohelicosporium griseum, two new polyketides, neogrisphenol A (1) and neogrisphenol B (2), one new isochroman-1-one, (S)-6-hydroxy-7-methoxy-3,5-dimethylisochroman-1-one (3), and four known compounds (4–7) were isolated. Their structures were determined using 1D- and 2D-NMR, mass spectrometry, and chemical calculations. The C-3~C-2′ polymerization mode between the two α-naphthalenone derivative moieties is uncommon in compounds 1 and 2. Meanwhile, compounds 1–2 and 5 exhibited antibacterial activity against Bacillus subtilis, Clostridium perfringens, Staphylococcus aureus, and Staphylococcus aureus, with MIC values ranging between 16 and 31 µg/mL. In addition, compound 5 showed antifungal activity against Sclerotinia sclerotiorum and Phytophthora nicotianae var. nicotianae, with respective IC50 values of 88.14 ± 2.21 µg/mL and 52.36 ± 1.38 µg/mL. Compound 1 showed significant cytotoxicity against A2780, PC-3, and MBA-MD-231...

Journal of Fungi

Uromyces is the second-largest plant pathogenic rust genus, is responsible for numerous diseases,... more Uromyces is the second-largest plant pathogenic rust genus, is responsible for numerous diseases, and has major effects on both agricultural and non-agricultural plants. The genus is generally characterized by its unicellular teliospores that help to characterize it and distinguish it from another important rust genus, Puccinia. In this study, a global overview of the diversity and distribution of Uromyces is presented based on both online and offline resources. The information obtained was analyzed for numerical and graphical summaries to provide the diversity and distribution of the genus by country and continent. Besides this, broad taxonomical aspects, a brief life cycle, and other comparative aspects on diversity and distribution were also provided. In addition, a phylogenetic analysis based on the ITS and nLSU DNA sequence data available in GenBank and published literature was performed to examine the intergeneric relationships of Uromyces. The results obtained revealed that t...

Pathogens

Coffee is grown in more than 80 countries as a cash crop and consumed worldwide as a beverage and... more Coffee is grown in more than 80 countries as a cash crop and consumed worldwide as a beverage and food additive. It is susceptible to fungal infection during growth, processing and storage. Fungal infections, in particular, can seriously affect the quality of coffee and threaten human health. The data for this comprehensive review were collected from the United States Department of Agriculture, Agricultural Research Service (USDA ARS) website and published papers. This review lists the fungal species reported on coffee based on taxonomy, life mode, host, affected plant part and region. Five major fungal diseases and mycotoxin-producing species (post-harvest diseases of coffee) are also discussed. Furthermore, we address why coffee yield and quality are affected by fungi and propose methods to control fungal infections to increase coffee yield and improve quality. Endophytic fungi and their potential as biological control agents of coffee disease are also discussed.

A fungus was collected from a dead twig of Ulmus minor  Ulmus pumila in Southern European Russia... more A fungus was collected from a dead twig of Ulmus minor  Ulmus pumila in Southern European Russia. The phylogenetic analysis based on combined gene regions of Internal transcribed spacer (ITS), the large subunit of nuclear ribosomal RNA (LSU), beta-tubulin (TUB2) and the second-largest subunit of nuclear RNA polymerase II (RPB2) sequence dataset shows that species clusters within the genus Nothophoma. Morphological characteristics and phylogenetic results confirmed that the fungus is Nothophoma quercina. Since this is the first report of N. quercina from Ulmus, we report this species as a new host record from Ulmus minor × Ulmus pumila in Russia. A detailed description, colour photographs and a phylogenetic tree to show the placement of N. quercina are given.

Fungal Diversity, 2021

Scientific names are crucial for communicating knowledge concerning fungi and fungus-like organis... more Scientific names are crucial for communicating knowledge concerning fungi and fungus-like organisms. In plant pathology, they link information regarding biology, host range, distribution and potential risk to agriculture and food security. In the past, delimitation among pathogenic taxa was primarily based on morphological characteristics. Due to distinct species sharing overlapping characteristics, the morphological identification of species is often neither straightforward nor reliable. Hence, the phylogenetic species concept based on molecular phylogenetic reconstructions gained importance. The present opinion discusses what a fungal species is and how identification of species in plant pathology has changed over the past decades. In this context, host-specialization and species complexes are discussed. Furthermore, species concepts in plant pathology are examined using case studies from Bipolaris, Colletotrichum, Curvularia, Diaporthe, Diplodia, Meliola, Plasmopara, rust fungi and Trichoderma. Each entry contains a brief introduction to the genus, concepts used in species identification so far and the problems in describing a species followed by recommendations. The importance of correctly naming and identifying a species is addressed in the context of recent introductions, and we also discuss whether the introduction of new species in pathogenic genera has been overestimated. We also provide guidelines to be considered when introducing a new species in a plant pathogenic genus.

Asian Journal of Mycology, 2020

Fungal Diversity, 2020

This is the twelfth contribution to the Fungal Diversity Notes series on fungal taxonomy, based o... more This is the twelfth contribution to the Fungal Diversity Notes series on fungal taxonomy, based on materials collected from many countries which were examined and described using the methods of morphology, anatomy, and strain culture, combined with DNA sequence analyses. 110 taxa are described and illustrated, including five new genera, 92 new species, eight new combinations and other taxonomic contributions (one new sequenced species, one new host and three new records) which are accommodated in 40 families and 1 incertae sedis in Dothideomycetes. The new genera are Amyloceraceomyces, Catenuliconidia, Hansenopezia, Ionopezia and Magnopulchromyces. The new species are Amyloceraceomyces angustisporus, Amylocorticium ellipsosporum,

Asian Journal of Mycology, 2020

Asian Journal of Mycology, 2019

Fungal Diversity, 2019

This paper is the second in a series focused on providing a stable platform for the taxonomy of p... more This paper is the second in a series focused on providing a stable platform for the taxonomy of phytopathogenic fungi. It focuses on 25 phytopathogenic genera: Alternaria, Bipolaris, Boeremia, Botryosphaeria, Calonectria, Coniella, Corticiaceae, Curvularia, Elsinoe, Entyloma, Erythricium, Fomitiporia, Fulviformes, Laetisaria, Limonomyces, Neofabraea, Neofusicoccum, Phaeoacremonium, Phellinotus, Phyllosticta, Plenodomus, Pseudopyricularia, Tilletia, Venturia and Waitea, using recent molecular data, up to date names and the latest taxonomic insights. For each genus a taxonomic background, diversity aspects, species identification and classification based on molecular phylogeny and recommended genetic markers are provided. In this study, varieties of the genus Boeremia have been elevated to species level. Botryosphaeria, Bipolaris, Curvularia, Neofusicoccum and Phyllosticta that were included in the One Stop Shop 1 paper are provided with updated entries, as many new species have been introduced to these genera.