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1.
J Fungi (Basel) ; 8(5)2022 May 17.
Article in English | MEDLINE | ID: mdl-35628771

ABSTRACT

During surveys of insect pathogenic fungi (IPF) in Thailand, fungi associated with scale insects and plants were found to represent five new species of the genus Ascopolyporus in Cordycipitaceae. Their macroscopic features resembled both Hyperdermium and Ascopolyporus. Morphological comparisons with the type and known Ascopolyporus and Hyperdermium species and phylogenetic evidence from a multigene dataset support the appointment of a new species of Ascopolyporus. Moreover, the data also revealed that the type species of Hyperdermium, H. caulium, is nested within Ascopolyporus, suggesting that Hyperdermium is congeneric with Ascopolyporus. The specimens investigated here differ from other Ascopolyporus species by phenotypic characters including size and color of stromata. Phylogenetic analyses of combined LSU, TEF1, RPB1 and RPB2 sequences strongly support the notion that these strains are distinct from known species of Ascopolyporus, and are proposed as Ascopolyporus albus, A. galloides, A. griseoperitheciatus, A. khaoyaiensis and A. purpuratus. Neohyperdermium gen. nov. is introduced for other species originally assigned to Hyperdermium and Cordyceps occurring on scale insects and host plants as epiphytes, accommodating two new combinations of Hyperdermium pulvinatum and Cordyceps piperis.

2.
MycoKeys ; 91: 113-149, 2022.
Article in English | MEDLINE | ID: mdl-36760890

ABSTRACT

Collections of pathogenic fungi found on spiders from Thailand were selected for a detailed taxonomic study. Morphological comparison and phylogenetic analyses of the combined ITS, LSU, tef1, rpb1 and rpb2 sequence data indicated that these specimens formed new independent lineages within the Cordycipitaceae, containing two new genera occurring on spiders, i.e. Jenniferia gen. nov. and Polystromomyces gen. nov. Two new species in Jenniferia, J.griseocinerea sp. nov. and J.thomisidarum sp. nov., are described. Two strains, NHJ 03510 and BCC 2191, initially named as Akanthomycescinereus (Hevansiacinerea), were shown to be part of Jenniferia. By including sequences of putative Hevansia species from GenBank, we also revealed Parahevansia as a new genus with the ex-type strain NHJ 666.01 of Pa.koratensis, accommodating specimens previously named as Akanthomyceskoratensis (Hevansiakoratensis). One species of Polystromomyces, Po.araneae sp. nov., is described. We established an asexual-sexual morph connection for Hevansianovoguineensis (Cordycipitaceae) with ex-type CBS 610.80 and proposed a new species, H.minuta sp. nov. Based on characteristics of the sexual morph, Hevansia and Polystromomyces share phenotypic traits by producing stipitate ascoma with fertile terminal heads; however, they differ in the shape and colour of the stipes. Meanwhile, Jenniferia produces non-stipitate ascoma with aggregated superficial perithecia forming a cushion. A new morphology of ascospores in Jenniferia is described, illustrated and compared with other species in Cordycipitaceae.

3.
Int J Syst Evol Microbiol ; 67(8): 3077-3082, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28857736

ABSTRACT

A novel actinomycete, designated strain EURKPP3H10T, was isolated from surface-sterilized roots of Eucalyptus camaldulensis Dehnh., collected from Kamphaengphet Silvicultural Research Station, Kamphaengphet province, Thailand. The taxonomic position of strain EURKPP3H10T was studied using a polyphasic approach. Phylogenetic evaluation based on 16S rRNA gene sequence analysis showed that strain EURKPP3H10T belongs to the genus Cryptosporangium, with the highest sequence similarity to Cryptosporangium cibodasense LIPI11-2-Ac046T (99.2 %). Colonies of strain EURKPP3H10T were orange yellow. Spherical sporangia with motile spores were observed. The strain contained meso-diaminopimelic acid and acofriose, arabinose, galactose, glucose, mannose, xylose and ribose in whole-cell hydrolysates. The predominant menaquinones were MK-9(H8) and MK-9(H6). The major fatty acids were iso-C16 : 0, C17 : 1ω8c, C18 : 1ω9c and C17 : 0. The polar lipids of the strain were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol and unknown lipids. The DNA G+C content of the genomic DNA was 71.5 mol%. Based on comparative analysis of physiological, biochemical and chemotaxonomic data, including DNA-DNA hybridization, strain EURKPP3H10T represents a novel species of the genus Cryptosporangium, for which the name Cryptosporangium eucalypti sp. nov. is proposed. The type strain is EURKPP3H10T (=BCC 77605T=NBRC 111482T).


Subject(s)
Actinomycetales/classification , Eucalyptus/microbiology , Phylogeny , Plant Roots/microbiology , Actinomycetales/genetics , Actinomycetales/isolation & purification , Bacterial Typing Techniques , Base Composition , DNA, Bacterial/genetics , Diaminopimelic Acid/chemistry , Fatty Acids/chemistry , Nucleic Acid Hybridization , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Thailand , Vitamin K 2/analogs & derivatives , Vitamin K 2/chemistry
4.
Microbiol Res ; 188-189: 42-52, 2016.
Article in English | MEDLINE | ID: mdl-27296961

ABSTRACT

In Thailand, Eucalyptus plantations rapidly expand across the country. Leaf and shoot blight caused by Cryptosporiopsis eucalypti, Cylindrocladium sp. and Teratosphaeria destructans is a serious disease in Eucalyptus plantations. In this study, a total of 477 actinomycete strains were successfully isolated from roots and rhizosphere soil of Eucalyptus. Four hundred and thirty nine isolates were classified as streptomycetes and 38 isolates were non-streptomycetes. Among these isolates, 272 (57.0%), 118 (24.7%) and 241 (50.5%) isolates were antagonistic to Cryptosporiopsis eucalypti, Cylindrocladium sp. and Teratosphaeria destructans, respectively. All isolates were tested for their abilities to produce siderophores, indole acetic acid (IAA) and solubilise phosphate. Most isolates (464, 97.3%) produced siderophores. The majority of isolates (345, 72.3%) solubilised phosphate. In addition, almost half of these isolates (237, 49.7%) produced indole acetic acid. Strain EUSKR2S82 which showed the strongest inhibitory effect against all tested fungi with plant growth promoting ability was selected to test with Eucalyptus. This strain could colonize plant roots and increase Eucalyptus roots length. In a detached leaves bioassay, the disease severity of EUSKR2S82-inoculated Eucalyptus leaves was only 30% compared to 95% in the control treatment. The 16S rRNA gene sequence analysis revealed that the strain EUSKR2S82 was related to Streptomyces ramulosus NRRL-B 2714(T) (99.44% similarity). Identification of non-streptomycete isolates using 16S rRNA gene sequences classified them into 9 genera: Actinoallomurus, Actinomadura, Amycolatopsis, Cryptosporangium, Microbispora, Micromonospora, Nocardia, Nonomuraea and Pseudonocardia. It is evident that Eucalyptus tree harbored several genera of actinomycetes. The selected isolate, EUSKR2S82 showed potential as a candidate for biocontrol agent of leaf and shoot blight of Eucalyptus and to promote growth.


Subject(s)
Actinobacteria/classification , Actinobacteria/physiology , Antibiosis , Eucalyptus/microbiology , Fungi/growth & development , Pest Control, Biological/methods , Plant Diseases/microbiology , Actinobacteria/genetics , Actinobacteria/isolation & purification , Biological Assay , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Microbiological Techniques , Microscopy , Phosphates/metabolism , Plant Diseases/prevention & control , Plant Growth Regulators/metabolism , Plant Leaves/microbiology , Plant Roots/microbiology , Plant Shoots/microbiology , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Soil Microbiology , Thailand
5.
BMC Ecol ; 11: 13, 2011 May 09.
Article in English | MEDLINE | ID: mdl-21554670

ABSTRACT

BACKGROUND: Parasites that manipulate host behavior can provide prominent examples of extended phenotypes: parasite genomes controlling host behavior. Here we focus on one of the most dramatic examples of behavioral manipulation, the death grip of ants infected by Ophiocordyceps fungi. We studied the interaction between O. unilateralis s.l. and its host ant Camponotus leonardi in a Thai rainforest, where infected ants descend from their canopy nests down to understory vegetation to bite into abaxial leaf veins before dying. Host mortality is concentrated in patches (graveyards) where ants die on sapling leaves ca. 25 cm above the soil surface where conditions for parasite development are optimal. Here we address whether the sequence of ant behaviors leading to the final death grip can also be interpreted as parasite adaptations and describe some of the morphological changes inside the heads of infected workers that mediate the expression of the death grip phenotype. RESULTS: We found that infected ants behave as zombies and display predictable stereotypical behaviors of random rather than directional walking, and of repeated convulsions that make them fall down and thus precludes returning to the canopy. Transitions from erratic wandering to death grips on a leaf vein were abrupt and synchronized around solar noon. We show that the mandibles of ants penetrate deeply into vein tissue and that this is accompanied by extensive atrophy of the mandibular muscles. This lock-jaw means the ant will remain attached to the leaf after death. We further present histological data to show that a high density of single celled stages of the parasite within the head capsule of dying ants are likely to be responsible for this muscular atrophy. CONCLUSIONS: Extended phenotypes in ants induced by fungal infections are a complex example of behavioral manipulation requiring coordinated changes of host behavior and morphology. Future work should address the genetic basis of such extended phenotypes.


Subject(s)
Ants/microbiology , Ants/physiology , Behavior, Animal/physiology , Hypocreales/physiology , Animals , Host-Parasite Interactions/physiology , Mycoses/physiopathology , Thailand
6.
PLoS One ; 4(3): e4835, 2009.
Article in English | MEDLINE | ID: mdl-19279680

ABSTRACT

Parasites are likely to play an important role in structuring host populations. Many adaptively manipulate host behaviour, so that the extended phenotypes of these parasites and their distributions in space and time are potentially important ecological variables. The fungus Ophiocordyceps unilateralis, which is pan-tropical in distribution, causes infected worker ants to leave their nest and die under leaves in the understory of tropical rainforests. Working in a forest dynamic plot in Southern Thailand we mapped the occurrence of these dead ants by examining every leaf in 1,360 m(2) of primary rainforest. We established that high density aggregations exist (up to 26 dead ants/m(2)), which we coined graveyards. We further established that graveyards are patchily distributed in a landscape with no or very few O. unilateralis-killed ants. At some, but not all, spatial scales of analysis the density of dead ants correlated with temperature, humidity and vegetation cover. Remarkably, having found 2243 dead ants inside graveyards we only found 2 live ants of the principal host, ant Camponotus leonardi, suggesting that foraging host ants actively avoid graveyards. We discovered that the principal host ant builds nests in high canopy and its trails only occasionally descend to the forest floor where infection occurs. We advance the hypothesis that rare descents may be a function of limited canopy access to tree crowns and that resource profitability of such trees is potentially traded off against the risk of losing workers due to infection when forest floor trails are the only access routes. Our work underscores the need for an integrative approach that recognises multiple facets of parasitism, such as their extended phenotypes.


Subject(s)
Ants/microbiology , Cordyceps/pathogenicity , Animals , Feeding Behavior , Plant Leaves/microbiology , Tropical Climate
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