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2.
J Fungi (Basel) ; 8(6)2022 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-35736096

RESUMEN

Symbiosis between beetles and fungi arose multiple times during the evolution of both organisms. Some of the most biologically diverse and economically important are mutualisms in which the beetles cultivate and feed on fungi. Among these are bark beetles and Harringtonia, a fungal genus that produces Raffaelea-like asexual morph and hosts the causal agent of laurel wilt, H. lauricola (formerly Raffaelea lauricola). In this study, we propose four new species of Harringtonia associated with beetles from Belize and Florida (USA). We hope to contribute towards a more robust and inclusive phylogenetic framework for future studies on these beetle-fungi relationships and their potential impact in crops and forests worldwide.

3.
Sports (Basel) ; 10(2)2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35202062

RESUMEN

The present study analyzed the effects from day-before to day-of bodybuilding competition on intracellular water (ICW), extracellular water (ECW), total body water (TBW), and bioimpedance analysis (BIA) parameters (resistance, R; reactance, Xc; and derived scores) in bodybuilding athletes. We assessed anthropometry and BIA (foot-to-hand; tetrapolar; 50 kHz) in 11 male bodybuilders (29 ± 4 year-old; 81 ± 8 kg; 172 ± 7 cm; 27 ± 2 kg/m2) both on the pre-competition day and on the contest day. Results revealed significant increases in ICW (31.6 ± 2.9 to 33.1 ± 2.8 L), with concomitant decreases in ECW (19.8 ± 1.8 to 17.2 ± 1.4 L) and TBW (51.4 ± 4.6 to 50.3 ± 4.2 L) from the day-before competition to contest day, which resulted in relatively large increases in the ICW/ECW ratio (1.60 ± 0.03 to 1.92 ± 0.01 L). Moreover, significant increases in R (391 ± 34 to 413 ± 33 ohm), Xc (64 ± 7 to 70 ± 6 ohm), and phase angle (9.3 ± 0.6 to 9.6 ± 0.7 degree) were observed between time periods. The phase angle scores reported on show-day of 9.6 and 11.2 appear to be the highest group mean and individual values observed in the literature to date. In conclusion, the strategies carried out on the final day of peak-week bodybuilding preparation lead to changes in BIA parameters and body water, with fluids shifting from the extra- to the intracellular compartment.

4.
J Fungi (Basel) ; 7(12)2021 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-34947025

RESUMEN

Symbiosis between insects and fungi arose multiple times during the evolution of both groups, and some of the most biologically diverse and economically important are mutualisms in which the insects cultivate and feed on fungi. Among these are bark beetles, whose ascomycetous cultivars are better known and studied than their frequently-overlooked and poorly understood basidiomycetous partners. In this study, we propose five new species of Entomocorticium, fungal mutualists in the Russulales (Basidiomycota) that are mutualistic symbionts of scolytine beetles. We have isolated these fungi from the beetle mycangia, which are structures adapted for the selective storage and transportation of fungal mutualists. Herein, we present the most complete phylogeny of the closely related genera Entomocorticium and Peniophora and provide insights into how an insect-associated taxon (Entomocorticium) evolved from within a wood-decaying, wind-dispersed lineage (Peniophora). Our results indicate that following a transition from angiosperms to gymnosperms, fungal domestication by beetles facilitated the evolution and diversification of Entomocorticium. We additionally propose four new species: Entomocorticium fibulatum Araújo, Li & Hulcr, sp. nov.; E. belizense Araújo, Li & Hulcr, sp. nov.; E. perryae Araújo, Li & Hulcr, sp. nov.; and E. macrovesiculatum Araújo, Li, Six & Hulcr, sp. nov. Our findings highlight the fact that insect-fungi associations remain an understudied field and that these associations harbor a large reservoir of novel fungal species.

5.
IMA Fungus ; 12(1): 3, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33541437

RESUMEN

The entomopathogenic genus Ophiocordyceps includes a highly diverse group of fungal species, predominantly parasitizing insects in the orders Coleoptera, Hemiptera, Hymenoptera and Lepidoptera. However, other insect orders are also parasitized by these fungi, for example the Blattodea (termites and cockroaches). Despite their ubiquity in nearly all environments insects occur, blattodeans are rarely found infected by filamentous fungi and thus, their ecology and evolutionary history remain obscure. In this study, we propose a new species of Ophiocordyceps infecting the social cockroaches Salganea esakii and S. taiwanensis, based on 16 years of collections and field observations in Japan, especially in the Ryukyu Archipelago. We found a high degree of genetic similarity between specimens from different islands, infecting these two Salganea species and that this relationship is ancient, likely not originating from a recent host jump. Furthermore, we found that Ophiocordyceps lineages infecting cockroaches evolved around the same time, at least twice, one from beetles and the other from termites. We have also investigated the evolutionary relationships between Ophiocordyceps and termites and present the phylogenetic placement of O. cf. blattae. Our analyses also show that O. sinensis could have originated from an ancestor infecting termite, instead of beetle larvae as previously proposed.

6.
Phytopathology ; 111(2): 304-311, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32734814

RESUMEN

The nematophagous fungal genus Esteya is reported as a natural enemy of the pine wood nematode Bursaphelenchus xylophilus, which causes pine wilt in Asia and Europe. During a survey of fungi associated with ambrosia beetles in Florida, an undescribed Esteya species was found. A phylogenetic analysis based on nuclear large subunit and ß-tubulin DNA sequences supported this isolate as a new species, E. floridanum. Morphological and phylogenetic characteristics and a species description are provided here. The fungus was observed to kill the pine wood nematode in vitro. To evaluate the ability of E. floridanum to protect trees against the pine wood nematode in vivo, the effect of prophylactic inoculation was tested on Pinus koraiensis and Larix olgensis in Liaoning, China. The results suggest that the fungus is not a plant pathogen and that it delays wilt and postpones death of two conifer trees. This presents a potential new avenue for research on biocontrol of pine wilt disease and stresses the value of research on pest organisms in their native regions.


Asunto(s)
Pinus , Tylenchida , Animales , Asia , China , Europa (Continente) , Florida , Filogenia , Enfermedades de las Plantas
7.
Fungal Biol ; 124(12): 983-1003, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33213787

RESUMEN

Witches' broom caused by Moniliophthora perniciosa is the main disease of cacao (Theobroma cacao) in Brazil. The fungus is known to occur on other host families and these populations have been addressed in the literature as biotypes: C (Malvaceae); H (Malpighiaceae); L (Bignoniaceae) and S (Solanaceae). No complete elucidation of the phylogenetic relationships of isolates obtained from this disparate host range appears in the literature. One member of H (ex Heteropterys acutifolia) has been described as a distinct species. But should other biotypes be also recognized as distinct taxa? In the present study, a survey yielding 24 isolates of M. perniciosa from ten hosts and covering a wide range of geographic regions in Brazil was undertaken. These isolates were compared with those from T. cacao using three DNA regions for the phylogenetic analyses: ITS, LSU and RPB1. Morphology was also examined. All isolates in this study were found to belong to M. perniciosa, including the population from H. acutifolia, formerly treated as Moniliophthora brasiliensis but reduced here to a synonym of M. perniciosa. This species ranged from pathogenic to a previously unreported occurrence as a non-pathogenic endophyte in the Atlantic rainforest tree Allophylus edulis (Sapindaceae). M. perniciosa was recorded on a range of solanaceous hosts (16 species) over a wide variety of ecosystems. The ecological and evolutionary significance of these novel findings are discussed.


Asunto(s)
Agaricales , Cacao , Enfermedad por Fitoplasma/microbiología , Enfermedades de las Plantas/microbiología , Agaricales/patogenicidad , Brasil , Cacao/microbiología , Ecosistema , Especificidad del Huésped , Filogenia
8.
J Invertebr Pathol ; 177: 107499, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33129891

RESUMEN

Hosts can be manipulated by parasites to move to locations advantageous for onward transmission. To investigate the role of behavioral manipulation in creating transmission hotspots, we studied the distribution of zombie turtle ants in the Amazon rainforest. The turtle ant Cephalotes atratus nests and mostly forages in the canopy, but is found at the base of trees when infected with the zombie ant fungus Ophiocordyceps kniphofioides. We found 626 infected cadavers on 14.8% of 162 trees sampled. Cadavers were highly aggregated on the surface of the trees, explained by behavioral observations indicating infected ants as slightly attracted to zombie ant cadavers on a tree. From 1,726 h of camera footage, we recorded the removal of three zombie ant cadavers by live ants. The number of removals compared to the density of infected individuals indicates the base of a tree as an escape from the evolved ability of social insects to recognize and treat disease inside the nest, allowing the parasite to continuously remain in the environment.


Asunto(s)
Hormigas/fisiología , Interacciones Huésped-Patógeno , Hypocreales/fisiología , Animales , Hormigas/microbiología , Brasil , Conducta Social , Árboles
9.
Mycologia ; 112(6): 1171-1183, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32484758

RESUMEN

The genus Ophiocordyceps contains the most diverse assemblage of fungi that attack ants worldwide and are remarkably well adapted to the specific ecologies of their hosts. Desmidiospora myrmecophila Thaxt. is closely related to other ant-pathogenic species within Ophiocordyceps, possibly specific to queens, but the sheer infrequency of encounters and previously unsuccessful attempts to culture this fungus has precluded any meaningful assessment until now. A new record of Desmidiospora myrmecophila from Louisiana was found infecting a foundress Camponotus pennsylvanicus queen, the same host species favored by the more common and ubiquitous ant-pathogenic Ophiocordyceps unilateralis clade found in the same geographic locality. To evaluate a long-held assumption that these fungi represent synanamorphs of a single species, we sampled our Desmidiospora specimen along with the local O. unilateralis population for molecular comparison. We are able to present for the first time the in vitro characteristics and morphology of Desmidiospora myrmecophila, as well as a phylogenetic context for this fungus based on combined molecular analysis of representative members of the Ophiocordycipitaceae. Our results place the Desmidiospora myrmecophila lineage within the genus Ophiocordyceps, with a basal affiliation to the Ophiocordyceps unilateralis core clade; thus, in accordance to the "One Fungus-One Name" (1F1N) rule, we propose a new synonym to suppress Desmidiospora in protection of Ophiocordyceps, i.e., O. desmidiospora. These results further implicate this species as an important and quintessential example of cryptic diversity among an already taxonomically diverse and ecologically important group of fungi.


Asunto(s)
Hormigas/microbiología , Hypocreales/clasificación , Hypocreales/genética , Filogenia , Animales , Variación Genética , Especificidad del Huésped , Hypocreales/citología , Hypocreales/aislamiento & purificación , Louisiana , Especificidad de la Especie
10.
Curr Biol ; 29(21): 3735-3738.e2, 2019 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-31668622

RESUMEN

The manipulation of animal behavior by parasitic organisms is one of the most complex adaptations to have arisen via natural selection. Among the most impressive examples of behavioral manipulation are the zombie-ant fungi [1]. In this association, ants are controlled to leave the colony and perform a stereotyped death grip behavior, where they bite onto vegetation over foraging trails, before being killed for the post mortem fungal growth. Manipulation functions to provide a platform outside the nest, from which fungal parasites actively shoot out spores, targeting foraging ants because within colony transmission is prevented by strong social immunity exhibited by social insect societies [2, 3]. It is not clear how such complex examples of host manipulation arose. To address this, we performed a broad-scale phylogenetic reconstruction of the order Hypocreales, to which the zombie-ant fungi, Ophiocordyceps, belong. In order to understand the patterns of host association and host switching along the evolution of Ophiocordyceps, we performed ancestral character state reconstruction analysis. We found that zombie-ant fungi likely arose from an ancestor that infected beetle larvae residing in soil or decaying wood, similar to extant beetle-infecting Ophiocordyceps species. Surprisingly, the jump led to an extensive species radiation observed after the development of behavioral manipulation. We suggest that the jump from solitary beetle larva to ants within a colony exposed the fungus to the robust social immunity of ant societies.


Asunto(s)
Hormigas/patogenicidad , Evolución Biológica , Escarabajos/patogenicidad , Interacciones Huésped-Patógeno , Hypocreales/fisiología , Animales , Hormigas/parasitología , Escarabajos/parasitología , Interacciones Huésped-Parásitos , Filogenia , Especificidad de la Especie
11.
Evolution ; 72(10): 2144-2155, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29808578

RESUMEN

Environmental conditions exert strong selection on animal behavior. We tested the hypothesis that the altered behavior of hosts due to parasitic manipulation is also subject to selection imposed by changes in environmental conditions over time. Our model system is ants manipulated by parasitic fungi to bite onto vegetation. We analyzed the correlation between forest type (tropical vs. temperate) and the substrate where the host bites (biting substrate: leaf vs. twigs), the time required for the fungi to reach reproductive maturity, and the phylogenetic relationship among specimens from tropical and temperate forests from different parts of the globe. We show that fungal development in temperate forests is longer than the period of time leaves are present and the ants are manipulated to bite twigs. When biting twigs, 90% of the dead ants we examined had their legs wrapped around twigs, which appears to provide better attachment to the plant. Ancestral state character reconstruction suggests that leaf biting is the ancestral trait and that twig biting is a convergent trait in temperate regions of the globe. These three lines of evidence suggest that changes in environmental conditions have shaped the manipulative behavior of the host by its parasite.


Asunto(s)
Hormigas/microbiología , Evolución Biológica , Bosques , Interacciones Huésped-Parásitos , Hypocreales/fisiología , Animales , Filogenia , Hojas de la Planta , Tallos de la Planta , Reproducción
12.
IMA Fungus ; 5(1): 121-34, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25083412

RESUMEN

Ophiocordycipitaceae is a diverse family comprising ecologically, economically, medicinally, and culturally important fungi. The family was recognized due to the polyphyly of the genus Cordyceps and the broad diversity of the mostly arthropod-pathogenic lineages of Hypocreales. The other two cordyceps-like families, Cordycipitaceae and Clavicipitaceae, will be revised taxonomically elsewhere. Historically, many species were placed in Cordyceps, but other genera have been described in this family as well, including several based on anamorphic features. Currently there are 24 generic names in use across both asexual and sexual life stages for species of Ophiocordycipitaceae. To reflect changes in Art. 59 in the International Code of Nomenclature for algae, fungi, and plants (ICN), we propose to protect and to suppress names within Ophiocordycipitaceae, and to present taxonomic revisions in the genus Tolypocladium, based on rigorous and extensively sampled molecular phylogenetic analyses. When approaching this task, we considered the principles of priority, monophyly, minimizing taxonomic revisions, and the practical utility of these fungi within the wider biological research community.

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