Tree Decay - An Expanded Concept

Treesearch

Alex L. Shigo

1979-01-01

The purpose of this publication is to clarify further the tree decay concept that expands the classical concept to include the orderly response of the tree to wounding and infection-compartmentalization-and the orderly infection of wounds by many microorganisms-successions. The heartrot concept must be abandoned because it deals only with decay-causing fungi and it...

Wood-Destroying Soft Rot Fungi in the Historic Expedition Huts of Antarctica

PubMed Central

Blanchette, Robert A.; Held, Benjamin W.; Jurgens, Joel A.; McNew, Douglas L.; Harrington, Thomas C.; Duncan, Shona M.; Farrell, Roberta L.

2004-01-01

Three expedition huts in the Ross Sea region of Antarctica, built between 1901 and 1911 by Robert F. Scott and Ernest Shackleton, sheltered and stored the supplies for up to 48 men for 3 years during their explorations and scientific investigation in the South Pole region. The huts, built with wood taken to Antarctica by the early explorers, have deteriorated over the past decades. Although Antarctica has one of the coldest and driest environments on earth, microbes have colonized the wood and limited decay has occurred. Some wood in contact with the ground contained distinct microscopic cavities within secondary cell walls caused by soft rot fungi. Cadophora spp. could be cultured from decayed wood and other woods sampled from the huts and artifacts and were commonly associated with the soft rot attack. By using internal transcribed spacer sequences of ribosomal DNA and morphological characteristics, several species of Cadophora were identified, including C. malorum, C. luteo-olivacea, and C. fastigiata. Several previously undescribed Cadophora spp. also were found. At the Cape Evans and Cape Royds huts, Cadophora spp. commonly were isolated from wood in contact with the ground but were not always associated with soft rot decay. Pure cultures of Cadophora used in laboratory decay studies caused dark staining of all woods tested and extensive soft rot in Betula and Populus wood. The presence of Cadophora species, but only limited decay, suggests there is no immediate threat to the structural integrity of the huts. These fungi, however, are widely found in wood from the historic huts and have the capacity to cause extensive soft rot if conditions that are more conducive to decay become common. PMID:15006750

Biodeterioration of wood

Treesearch

Terry L. Highley

1999-01-01

Under proper conditions, wood will give centuries of service. However, if conditions exist that permit the development of wood-degrading organisms, protection must be provided during processing, merchandising, and use. The principal organisms that can degrade wood are fungi, insects, bacteria, and marine borers. Molds, most sapwood stains, and decay are caused by fungi...

Five New Wood Decay Fungi (Polyporales and Hymenochaetales) in Korea.

PubMed

Kim, Nam Kyu; Park, Jae Young; Park, Myung Soo; Lee, Hyun; Cho, Hae Jin; Eimes, John A; Kim, Changmu; Lim, Young Woon

2016-09-01

The wood decay fungi are a diverse taxonomic group that plays a pivotal role in forest carbon cycling. Wood decay fungi use various enzymatic pathways to digest dead or living wood in order to obtain carbon and other nutrients and these enzymatic systems have been exploited for both industrial and medical applications. Over 600 wood decay fungi species have been described in Korea; however, the recent application of molecular markers has dramatically altered the taxonomy of many of these wood decay fungi at both the genus and species levels. By combining molecular methods, specifically sequences of the internal transcribed spacer region, with traditional morphological characters, this study identified five new species records for Korea in five genera: Aurantiporus , Favolus , Neofavolus , Loweomyces , and Hymenochaetopsis . Three of these genera ( Aurantiporus , Favolus , and Loweomyces ) were previously unknown in Korea. The relatively simple morphology of the wood decay fungi often leads to ambiguous taxonomic assignment. Therefore, molecular markers are a necessary component of any taxonomic or evolutionary study of wood decay fungi. Our study highlights the need for a more robust and multifaceted approach in investigating new wood decay fungi in Korea.

Natural decomposition of hornbeam wood decayed by the white rot fungus Trametes versicolor.

PubMed

Karim, Maryam; Daryaei, Mehrdad Ghodskhah; Torkaman, Javad; Oladi, Reza; Ghanbary, Mohammad Ali Tajick; Bari, Ehsan; Yilgor, Nural

2017-01-01

The impacts of white-rot fungi on altering wood chemistry have been studied mostly in vitro. However, in vivo approaches may enable better assessment of the nature of interactions between saprotrophic fungi and host tree in nature. Hence, decayed and sound wood samples were collected from a naturally infected tree (Carpinus betulus L.). Fruiting bodies of the white rot fungus Trametes versicolor grown on the same tree were identified using rDNA ITS sequencing. Chemical compositions (cellulose and lignin) of both sound and infected wood were studied. FT-IR spectroscopy was used to collect spectra of decayed and un-decayed wood samples. The results of chemical compositions indicated that T. versicolor reduced cellulose and lignin in similar quantities. Fungal activities in decayed wood causes serious decline in pH content. The amount of alcohol-benzene soluble extractives was severely decreased, while a remarkable increase was found in 1% sodium hydroxide soluble and hot water extractive contents in the decayed wood samples, respectively. FT-IR analyses demonstrated that T. versicolor causes simultaneous white rot in the hornbeam tree in vivo which is in line with in vitro experiments.

Five New Wood Decay Fungi (Polyporales and Hymenochaetales) in Korea

PubMed Central

Kim, Nam Kyu; Park, Jae Young; Park, Myung Soo; Lee, Hyun; Cho, Hae Jin; Eimes, John A.; Kim, Changmu

2016-01-01

The wood decay fungi are a diverse taxonomic group that plays a pivotal role in forest carbon cycling. Wood decay fungi use various enzymatic pathways to digest dead or living wood in order to obtain carbon and other nutrients and these enzymatic systems have been exploited for both industrial and medical applications. Over 600 wood decay fungi species have been described in Korea; however, the recent application of molecular markers has dramatically altered the taxonomy of many of these wood decay fungi at both the genus and species levels. By combining molecular methods, specifically sequences of the internal transcribed spacer region, with traditional morphological characters, this study identified five new species records for Korea in five genera: Aurantiporus, Favolus, Neofavolus, Loweomyces, and Hymenochaetopsis. Three of these genera (Aurantiporus, Favolus, and Loweomyces) were previously unknown in Korea. The relatively simple morphology of the wood decay fungi often leads to ambiguous taxonomic assignment. Therefore, molecular markers are a necessary component of any taxonomic or evolutionary study of wood decay fungi. Our study highlights the need for a more robust and multifaceted approach in investigating new wood decay fungi in Korea. PMID:27790065

Using isotopic patterns of ectomycorrhizal and saprotrophic fungi to elucidate fungal sources of carbon and nitrogen in a Norway spruce stand

NASA Astrophysics Data System (ADS)

Chen, Janet; Rinne-Garmston, Katja; Penttilä, Reijo; Hobbie, Erik; Mäkipää, Raisa

2016-04-01

To predict effects of global change on fungal community structure and the consequential effects on carbon (C) and nitrogen (N) cycling, we first need to understand different fungal sources of C and N. We determined sources of C and N by measuring δ15N and δ13C of an extensive collection of ectomycorrhizal and saprotrophic sporocarps and their potential substrates from Norway spruce (Picea abies) stands in southern Finland. The substrates included organic soil, roots in organic soil, mineral soil, roots in mineral soil, moss, needles, needles in litter, branches, twigs in litter, wood and decay wood from stages I-V. Notably, δ15N and δ13C analysis of wood in decay stages I-V was a novel measurement, as were our associations between wood decay fungi and the decay stage of trees. Decay stage of wood significantly correlated with the δ15N and δ13C of associated saprotrophic wood decay fungi species. Fungi were lower in δ15N by 0.3-0.7‰ when associated with decay wood in stages II and III compared to I and IV and higher in δ13C by 0.9-1.2‰ when associated with decay stage I compared to decay stages II-IV. The ectomycorrhizal fungi, Piloderma fallax, was significantly correlated with 15N enrichment of decay wood upon its introduction in decay stages III and IV that continued to the later decay stage V, with δ15N of decay stage V 1.5‰ higher than decay stage IV. These results indicate that wood decay fungi rely on C and N from various wood decay stages and influence C and N pools of wood as well. Litter decay fungi were lower in δ13C than wood decay fungi by 1.9‰ and higher in δ15N by 3‰ and isotopically tracked their C and N sources. Calocera viscosa, Gymnopus acervatus, and Leotia lubrica were highly 15N-enriched compared to other saprotrophic fungi and they had δ15N values similar to fungi with hydrophobic ectomycorrhizae indicating function more similar to ectomycorrhizal fungi or N sources similar to this functional group. Similar to other studies, ectomycorrhizal fungi were 15N-enriched relative to saprotrophic fungi and fungi with hydrophobic ectomycorrhizae were 15N-enriched compared to fungi with hydrophilic ectomycorrhizae by 3.6‰. δ15N and δ13C values indicate that ectomycorrhizal fungi derive C from plant sugars similar to woody substrate, and acquire N from older sources within the litter layer and deeper in organic and mineral soils, with hydrophobic ectomycorrhizae using older sources of N than hydrophilic ectomycorrhizae. Interestingly, Entoloma cetratum with hydrophilic ectomycorrhizae and Hydnum repandum with hydrophobic ectomycorrhizae both had abnormally high δ15N values that suggest an irregular 15N-enriched source of N, likely from a higher 15N-enriched trophic level.

Determination of fungal diseases, site and stand characteristics in mixed stands in Ilgaz-Yenice forest district, Cankiri, Turkey.

PubMed

Oner, Nuri; Dogan, Hasan Huseyin; Ozturk, Celaleddin; Gurer, Meral

2009-07-01

Fungal diseases, site and stand characteristics were investigated in Yenice forest sub-district headquarters belonging to Ilgaz forest enterprise. Diseases and wood decaying fungi on fallen and cut tree stumps were determined on scots pine (Pinus sylvestris), crimean pine (P. nigra subsp. nigra varcaramanica), and uludag fir (Abies nordmanniana subsp. bommulleriana). Altitude (m), exposure, slope (%), relief, rate of mixture (%) and anthropogenic effects were noted for 56 sample plots which have various stand compositions. Age, breast height diameter (cm), top height (m), crown and bole quality regeneration quality and development of representative tree species were also recorded into vegetation forms. Yellow witches' broom (Melampsorella caryophyllacearum), which caused drying of uludag fir trees, was determined. Besides, 53 macrofungi species belonging to 3 divisions, 10 orders, 25 families and 36 genera were determined. Some of them cause white and brown decay on living and core wood. The most common parasitic and saprobe fungi are Galerina Ganoderma, Gloeophyllum, Gymnopilus, Hypholoma, Lentinus, Phellinus, Pleurotus, Polyporus and Stereum species in the research area. Trichaptum abietinum is also typical wood decay fungi for living or cut fir trees and it is very common in the research area.

Decay and termite resistance, water absorption and swelling of thermally compressed wood panels

Treesearch

Oner Unsal; S. Nami Kartal; Zeki Candan; Rachel A. Arango; Carol A. Clausen; Frederick Green

2009-01-01

This study evaluated decay and termite resistance of thermally compressed pine wood panels under pressure at either 5 or 7 MPa and either 120 or 150 °C for 1 h. Wood specimens from the panels were exposed to laboratory decay resistance by using the wood degrading fungi, Gloeophyllum trabeum and Trametes versicolor. The thermal compression process caused increases in...

The impact of the postharvest environment on the viability and virulence of decay fungi.

PubMed

Liu, Jia; Sui, Yuan; Wisniewski, Michael; Xie, Zhigang; Liu, Yiqing; You, Yuming; Zhang, Xiaojing; Sun, Zhiqiang; Li, Wenhua; Li, Yan; Wang, Qi

2018-07-03

Postharvest decay of fruits, vegetables, and grains by fungal pathogens causes significant economic losses. Infected produce presents a potential health risk since some decay fungi produce mycotoxins that are hazardous to human health. Infections are the result of the interplay between host resistance and pathogen virulence. Both of these processes, however, are significantly impacted by environmental factors, such as temperature, UV, oxidative stress, and water activity. In the present review, the impact of various physical postharvest treatments (e.g., heat and UV) on the viability and virulence of postharvest pathogens is reviewed and discussed. Oxidative injury, protein impairment, and cell wall degradation have all been proposed as the mechanisms by which these abiotic stresses reduce fungal viability and pathogenicity. The response of decay fungi to pH and the ability of pathogens to modulate the pH of the host environment also affect pathogenicity. The effects of the manipulation of the postharvest environment by ethylene, natural edible coatings, and controlled atmosphere storage on fungal viability are also discussed. Lastly, avenues of future research are proposed.

The effects of environmental conditions on the growth of Merulius lacrymans

Treesearch

Jesse D. Diller; E. James Koch

1960-01-01

The two building decay fungi, the European Merulius lacrymans Fr. and the native Poria incrassate (Berk. & Curt.) Burt., do not often become established in buildings. But when they do, these fungi can cause serious damage to structural timbers. In extreme cases they have advanced to the second and third floor of buildings. This...

Field guide to common macrofungi in eastern forests and their ecosystem functions

Treesearch

Michael E. Ostry; Neil A. Anderson; Joesph G. O' Brien

2011-01-01

Macrofungi are distinguished from other fungi by their spore-bearing fruit bodies (mushrooms, conks, brackets). These fungi are critical in forests, causing disease, and wood and litter decay, recycling nutrients, and forming symbiotic relationships with trees. This guide is intended to assist in identifying macrofungi and provide a description of the ecological...

Strength reduction in slash pine (Pinus elliotii) wood caused by decay fungi

Treesearch

Zhong Yang; Zhehui Jiang; Chung Y. Hse; Todd F. Shupe

2009-01-01

Small wood specimens selected from slash pine (Pinus elliotii )trees at three growth rates (fast, medium, and slow) were inoculated with brown-rot and white-rot fungi and then evaluated for work to maximum load (WML), modulus of rupture (MOR), and modulus of elasticity (MOE). The experimental variables studied included a brown-rot fungus (Gloeophyllum trabeum...

Changes in the Chemical Composition and Decay Resistance of Thermally-Modified Hevea brasiliensis Wood

PubMed Central

2016-01-01

In this study the effect of thermal treatment on the equilibrium moisture content, chemical composition and biological resistance to decay fungi of juvenile and mature Hevea brasiliensis wood (rubber wood) was evaluated. Samples were taken from a 53-year-old rubber wood plantation located in Tabapuã, Sao Paulo, Brazil. The samples were thermally-modified at 180°C, 200°C and 220°C. Results indicate that the thermal modification caused: (1) a significant increase in the extractive content and proportional increase in the lignin content at 220°C; (2) a significant decrease in the equilibrium moisture content, holocelluloses, arabinose, galactose and xylose content, but no change in glucose content; and (3) a significant increase in wood decay resistance against both Pycnoporus sanguineus (L.) Murrill and Gloeophyllum trabeum (Pers.) Murrill decay fungi. The greatest decay resistance was achieved from treatment at 220°C which resulted in a change in wood decay resistance class from moderately resistant to resistant. Finally, this study also demonstrated that the influence of thermal treatment in mature wood was lower than in juvenile wood. PMID:26986200

Deception Island, Antarctica, harbors a diverse assemblage of wood decay fungi.

PubMed

Held, Benjamin W; Blanchette, Robert A

2017-02-01

Very little is known about fungal diversity in Antarctica as compared to other biomes and how these important organisms function in this unusual ecosystem. Perhaps one of the most unusual ecosystems is that of Deception Island; an active volcanic island part of the South Shetland Islands of the Antarctic Peninsula. Here we describe the fungal diversity associated with historic wood from structures on the island, which reveals a diverse fungal assemblage of known wood decay fungi as well as the discovery of undescribed species. The major group of wood decay fungi identified were species of Cadophora and as shown in previous studies in other geographic regions of Antarctica, they caused a soft-rot type of decay in the introduced woods. Additionally, unlike other areas of Antarctica that have been studied, filamentous basidiomycetes (Hypochniciellum spp. and Pholiota spp.) were also identified that have different modes of degradation including brown and white rot. Matches of fungal sequences to known species in temperate regions likely introduced on building materials indicates human influences and volcanic activity have greatly impacted fungal diversity. Lahars (mudslides from volcanic activity) have partially buried many of the structures and the buried environment as well as the moist, warm soils provided conditions conducive for fungal growth that are not found in other regions of Antarctica. The diverse assemblage of decay fungi and different forms of wood decomposition add to the difficulty of conserving wooden structures at these important polar heritage sites. Copyright © 2016 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Evaluation of a portable MOS electronic nose to detect root rots in shade tree species

Treesearch

Manuela Baietto; Letizia Pozzi; Alphus Dan Wilson; Daniele Bassi

2013-01-01

The early detection of wood decays in high-value standing trees is very important in urban areas because mitigating control measures must be implemented long before tree failures result in property damage or injuries to citizens. Adverse urban environments increase physiological stresses in trees, causing greater susceptibility to attacks by pathogenic decay fungi. The...

Systematic search for cultivatable fungi that best deconstruct cell walls of Miscanthus and sugarcane in the field.

PubMed

Shrestha, Prachand; Szaro, Timothy M; Bruns, Thomas D; Taylor, John W

2011-08-01

The goals of our project were to document the diversity and distributions of cultivable fungi associated with decaying Miscanthus and sugarcane plants in nature and to further assess biodegradation of host plant cell walls by these fungi in pure cultures. Late in 2008 and early in 2009 we collected decaying Miscanthus and Saccharum from 8 sites in Illinois and 11 sites in Louisiana, respectively. To recover fungi that truly decay plants and to recover slow-growing fungi, we washed the plant material repeatedly to remove spores and cultivated fungi from plant fragments small enough to harbor at most one mycelium. We randomly selected 950 fungal colonies out of 4,560 microwell colonies and used molecular identification to discover that the most frequently recovered fungal species resided in Hypocreales (Sordariomycetes), Pleosporales (Dothideomycetes), and Chaetothryiales (Eurotiomycetes) and that only a few weedy species were recovered. We were particularly interested in Pleosporales and Chaetothyriales, groups that have not been mined for plant decay fungi. To confirm that we had truly recovered fungi that deconstruct plant cell walls, we assayed the capacity of the fungi to consume whole, alkali-pretreated, ground Miscanthus. Solid substrate cultures of the nine most commonly encountered Ascomycota resulted in Miscanthus weight loss of 8 to 13% over 4 weeks. This is the first systematic, high-throughput, isolation and biodegradation assessment of fungi isolated from decaying bioenergy grasses.

Investigations of biodeterioration by fungi in historic wooden churches of Chiloé, Chile.

PubMed

Ortiz, Rodrigo; Párraga, Mario; Navarrete, José; Carrasco, Ivo; de la Vega, Eduardo; Ortiz, Manuel; Herrera, Paula; Jurgens, Joel A; Held, Benjamin W; Blanchette, Robert A

2014-04-01

The use of wood in construction has had a long history and Chile has a rich cultural heritage of using native woods for building churches and other important structures. In 2000, UNESCO designated a number of the historic churches of Chiloé, built entirely of native woods, as World Heritage Sites. These unique churches were built in the late 1700 s and throughout the 1800 s, and because of their age and exposure to the environment, they have been found to have serious deterioration problems. Efforts are underway to better understand these decay processes and to carryout conservation efforts for the long-term preservation of these important structures. This study characterized the types of degradation taking place and identified the wood decay fungi obtained from eight historic churches in Chiloé, seven of them designated as UNESCO World Heritage sites. Micromorphological observations identified white, brown and soft rot in the structural woods and isolations provided pure cultures of fungi that were identified by sequencing of the internal transcribed region of rDNA. Twenty-nine Basidiomycota and 18 Ascomycota were found. These diverse groups of fungi represent several genera and species not previously reported from Chile and demonstrates a varied microflora is causing decay in these historic buildings.

Volatile organic compounds from Wickerhamomyces anomalus, Metschnikowia pulcherrima and Saccharomyces cerevisiae inhibit growth of decay causing fungi and control postharvest diseases of strawberries.

PubMed

Oro, Lucia; Feliziani, Erica; Ciani, Maurizio; Romanazzi, Gianfranco; Comitini, Francesca

2018-01-16

The effectiveness of Wickerhamomyces anomalus, Metschnikowia pulcherrima and Saccharomyces cerevisiae as biocontrol agents on postharvest decay of strawberry (Fragaria x ananassa, cv. 'Alba') fruit, and their inhibitory activities on some decay-causing fungi were evaluated. Volatile organic compounds from these yeasts decreased mycelial growth of Botrytis cinerea by 69%, and by less for Monilinia fructicola, Alternaria alternata, Aspergillus carbonarius, Penicillium digitatum, Cladosporium spp., and Colletotrichum spp. Strawberry fruit exposed to 6-day-old liquid cultures of W. anomalus, M. pulcherrima and S. cerevisiae for 48h showed 89%, 40%, and 32% reductions, respectively, in gray mold McKinney Index. Vapours of ethyl acetate, the main volatile organic compound of these yeasts, completely inhibited B. cinerea growth at 8.97mg/cm 3 , and suppressed gray mold on strawberry fruit at 0.718mg/cm 3 . The biocontrol activities of these yeasts can be ascribed to ethyl acetate, which can be used for control of postharvest gray mold of strawberry fruit. Copyright © 2017 Elsevier B.V. All rights reserved.

Systematic Search for Cultivatable Fungi That Best Deconstruct Cell Walls of Miscanthus and Sugarcane in the Field ▿ †

PubMed Central

Shrestha, Prachand; Szaro, Timothy M.; Bruns, Thomas D.; Taylor, John W.

2011-01-01

The goals of our project were to document the diversity and distributions of cultivable fungi associated with decaying Miscanthus and sugarcane plants in nature and to further assess biodegradation of host plant cell walls by these fungi in pure cultures. Late in 2008 and early in 2009 we collected decaying Miscanthus and Saccharum from 8 sites in Illinois and 11 sites in Louisiana, respectively. To recover fungi that truly decay plants and to recover slow-growing fungi, we washed the plant material repeatedly to remove spores and cultivated fungi from plant fragments small enough to harbor at most one mycelium. We randomly selected 950 fungal colonies out of 4,560 microwell colonies and used molecular identification to discover that the most frequently recovered fungal species resided in Hypocreales (Sordariomycetes), Pleosporales (Dothideomycetes), and Chaetothryiales (Eurotiomycetes) and that only a few weedy species were recovered. We were particularly interested in Pleosporales and Chaetothyriales, groups that have not been mined for plant decay fungi. To confirm that we had truly recovered fungi that deconstruct plant cell walls, we assayed the capacity of the fungi to consume whole, alkali-pretreated, ground Miscanthus. Solid substrate cultures of the nine most commonly encountered Ascomycota resulted in Miscanthus weight loss of 8 to 13% over 4 weeks. This is the first systematic, high-throughput, isolation and biodegradation assessment of fungi isolated from decaying bioenergy grasses. PMID:21685162

Effect of Trichoderma-enriched organic charcoal in the integrated wood protection strategy

PubMed Central

Gandía, Mónica; Marcos, Jose F.; Bas, Maria del Carmen; Fink, Siegfried

2017-01-01

The gradual elimination of chromium from wood preservative formulations results in higher Cu leaching and increased susceptibility to wood decay fungi. Finding a sustainable strategy in wood protection has become of great interest among researchers. The objective of these in vitro studies was to demonstrate the effect of T-720-enriched organic charcoal (biochar) against five wood decay basidiomycetes isolated from strongly damaged poles. For this purpose, the antagonistic potential of Trichoderma harzianum (strain T-720) was confirmed among other four Trichoderma spp. against five brown-rot basidiomycetes in dual culture tests. T-720 was genetically transformed and tagged with the green fluorescent protein (GFP) in order to study its antagonistic mechanism against wood decay basidiomycetes. It was also demonstrated that T-720 inhibits the oxalic acid production by basidiomycetes, a well-known mechanism used by brown-rot fungi to detoxify Cu from impregnated wood. Additionally, this study evaluated the effect of biochar, alone or in combination with T-720, on Cu leaching by different preservatives, pH stabilization and prevention of wood decay caused by five basidiomycetes. Addition of biochar resulted in a significant Cu binding released from impregnated wood specimens. T-720-enriched biochar showed a significant reduction of wood decay caused by four basidiomycetes. The addition of T-720-enriched biochar to the soil into which utility poles are placed may improve the efficiency of Cr-free wood preservatives. PMID:28797118

Effect of Trichoderma-enriched organic charcoal in the integrated wood protection strategy.

PubMed

Ribera, Javier; Gandía, Mónica; Marcos, Jose F; Bas, Maria Del Carmen; Fink, Siegfried; Schwarze, Francis W M R

2017-01-01

The gradual elimination of chromium from wood preservative formulations results in higher Cu leaching and increased susceptibility to wood decay fungi. Finding a sustainable strategy in wood protection has become of great interest among researchers. The objective of these in vitro studies was to demonstrate the effect of T-720-enriched organic charcoal (biochar) against five wood decay basidiomycetes isolated from strongly damaged poles. For this purpose, the antagonistic potential of Trichoderma harzianum (strain T-720) was confirmed among other four Trichoderma spp. against five brown-rot basidiomycetes in dual culture tests. T-720 was genetically transformed and tagged with the green fluorescent protein (GFP) in order to study its antagonistic mechanism against wood decay basidiomycetes. It was also demonstrated that T-720 inhibits the oxalic acid production by basidiomycetes, a well-known mechanism used by brown-rot fungi to detoxify Cu from impregnated wood. Additionally, this study evaluated the effect of biochar, alone or in combination with T-720, on Cu leaching by different preservatives, pH stabilization and prevention of wood decay caused by five basidiomycetes. Addition of biochar resulted in a significant Cu binding released from impregnated wood specimens. T-720-enriched biochar showed a significant reduction of wood decay caused by four basidiomycetes. The addition of T-720-enriched biochar to the soil into which utility poles are placed may improve the efficiency of Cr-free wood preservatives.

Comparison of effectiveness of wood decay fungi maintained by annual subculture on agar and stored in sterile water for 18 years.

PubMed

Richter, Dana L; Kangas, Laura C; Smith, Jill K; Laks, Peter E

2010-03-01

Fourteen isolates of basidiomycete decay fungi (12 species) were maintained for 18 years on agar slants transferred annually and also stored as mycelium-agar cores under cold sterile water without subculture. Isolates stored by each method were evaluated for decay effectiveness using a standard laboratory accelerated soil-block decay test. Effectiveness was measured by mean percent mass loss of wood blocks. There was no significant difference (p < or = 0.05) in decay effectiveness between storage methods for 12 of the fungus isolates tested. For the 2 fungi that showed a significant difference in the amount of decay with respect to storage method, 1 fungus (Fomitopsis lilacinogilva) produced more decay by the strain maintained as an agar slant, while the other fungus (Trametes versicolor) produced more decay by the strain stored in sterile water. Results suggested that storage under sterile water is an easy and effective method to store isolates of decay fungi for long periods, but as with any microbial storage method, careful monitoring of isolates upon revival is necessary.

Online resources for the identification of North American wood decay fungi

Treesearch

Jessie A. Glaeser

2012-01-01

The ability to identify wood decay fungi is an important skill for an arborist. Knowing which fungus is colonizing a tree can be used to better assess the type, amount, and position of decay in the tree, and its subsequent effects on wood strength. Distinguishing species of fungi that colonize sapwood, heartwood, or roots can provide information to improve the quality...

Bull’s-eye rot management: understanding the disease cycle of Neofabraea spp. occurring on apples grown in the Pacific Northwest

USDA-ARS?s Scientific Manuscript database

In the US Pacific Northwest, bull’s-eye rot of pome fruit, caused by Neofabraea spp., is a major quarantine concern. Of the four fungi causing this disease, Neofabraea perennans and N. kienholzii are common in north central Washington. In addition to fruit decay, N. perennans causes perennial cank...

Detection and Identification of Decay Fungi in Spruce Wood by Restriction Fragment Length Polymorphism Analysis of Amplified Genes Encoding rRNA†

PubMed Central

Jasalavich, Claudia A.; Ostrofsky, Andrea; Jellison, Jody

2000-01-01

We have developed a DNA-based assay to reliably detect brown rot and white rot fungi in wood at different stages of decay. DNA, isolated by a series of CTAB (cetyltrimethylammonium bromide) and organic extractions, was amplified by the PCR using published universal primers and basidiomycete-specific primers derived from ribosomal DNA sequences. We surveyed 14 species of wood-decaying basidiomycetes (brown-rot and white-rot fungi), as well as 25 species of wood-inhabiting ascomycetes (pathogens, endophytes, and saprophytes). DNA was isolated from pure cultures of these fungi and also from spruce wood blocks colonized by individual isolates of wood decay basidiomycetes or wood-inhabiting ascomycetes. The primer pair ITS1-F (specific for higher fungi) and ITS4 (universal primer) amplified the internal transcribed spacer region from both ascomycetes and basidiomycetes from both pure culture and wood, as expected. The primer pair ITS1-F (specific for higher fungi) and ITS4-B (specific for basidiomycetes) was shown to reliably detect the presence of wood decay basidiomycetes in both pure culture and wood; ascomycetes were not detected by this primer pair. We detected the presence of decay fungi in wood by PCR before measurable weight loss had occurred to the wood. Basidiomycetes were identified to the species level by restriction fragment length polymorphisms of the internal transcribed spacer region. PMID:11055916

A review of the role of fungi in wood decay of forest ecosystems

Treesearch

Bruce G. Marcot

2017-01-01

Fungi are key players in the health, diversity, and productivity of forest ecosystems in Pacific Northwest forests, as mycorrhizal associations, pathogens, decomposers, nontimber resources, and food resources for wildlife. A number of invertebrate species are associated with wood decay fungi, serve as vectors for fungal pathogens, or are fungivorous (consume fungi) and...

[The influence of oil heat treatment on wood decay resistance by Fourier infrared spectrum analysis].

PubMed

Wang, Ya-Mei; Ma, Shu-Ling; Feng, Li-Qun

2014-03-01

Wood preservative treatment can improve defects of plantation wood such as easy to corrupt and moth eaten. Among them heat-treatment is not only environmental and no pollution, also can improve the corrosion resistance and dimension stability of wood. In this test Poplar and Mongolian Seoteh Pine was treated by soybean oil as heat-conducting medium, and the heat treatment wood was studied for indoor decay resistance; wood chemical components before and after treatment, the effect of heat treatment on wood decay resistance performance and main mechanism of action were analysed by Fourier infrared spectrometric. Results showed that the mass loss rate of poplar fell from 19.37% to 5% and Mongolian Seoteh Pine's fell from 8.23% to 3.15%, so oil heat treatment can effectively improve the decay resistance. Infrared spectrum analysis shows that the heat treatment made wood's hydrophilic groups such as hydroxyl groups in largely reduced, absorbing capacity decreased and the moisture of wood rotting fungi necessary was reduced; during the heat treatment wood chemical components such as cellulose, hemicellu lose were degraded, and the nutrient source of wood rotting fungi growth necessary was reduced. Wood decay fungi can grow in the wood to discredit wood is because of that wood can provide better living conditions for wood decay fungi, such as nutrients, water, oxygen, and so on. The cellulose and hemicellulose in wood is the main nutrition source of wood decay fungi. So the oil heat-treatment can reduce the cellulose, hemicellulose nutrition source of wood decay fungi so as to improve the decay resistance of wood.

Visual cues for woodpeckers: light reflectance of decayed wood varies by decay fungus

USGS Publications Warehouse

O'Daniels, Sean T.; Kesler, Dylan C.; Mihail, Jeanne D.; Webb, Elisabeth B.; Werner, Scott J.

2018-01-01

The appearance of wood substrates is likely relevant to bird species with life histories that require regular interactions with wood for food and shelter. Woodpeckers detect decayed wood for cavity placement or foraging, and some species may be capable of detecting trees decayed by specific fungi; however, a mechanism allowing for such specificity remains unidentified. We hypothesized that decay fungi associated with woodpecker cavity sites alter the substrate reflectance in a species-specific manner that is visually discriminable by woodpeckers. We grew 10 species of wood decay fungi from pure cultures on sterile wood substrates of 3 tree species. We then measured the relative reflectance spectra of decayed and control wood wafers and compared them using the receptor noise-limited (RNL) color discrimination model. The RNL model has been used in studies of feather coloration, egg shells, flowers, and fruit to model how the colors of objects appear to birds. Our analyses indicated 6 of 10 decayed substrate/control comparisons were above the threshold of discrimination (i.e., indicating differences discriminable by avian viewers), and 12 of 13 decayed substrate comparisons were also above threshold for a hypothetical woodpecker. We conclude that woodpeckers should be capable of visually detecting decayed wood on trees where bark is absent, and they should also be able to detect visually species-specific differences in wood substrates decayed by fungi used in this study. Our results provide evidence for a visual mechanism by which woodpeckers could identify and select substrates decayed by specific fungi, which has implications for understanding ecologically important woodpecker–fungus interactions.

Spore sensitivity to sunlight and freezing can restrict dispersal in wood-decay fungi

PubMed Central

Norros, Veera; Karhu, Elina; Nordén, Jenni; Vähätalo, Anssi V; Ovaskainen, Otso

2015-01-01

Assessment of the costs and benefits of dispersal is central to understanding species' life-history strategies as well as explaining and predicting spatial population dynamics in the changing world. While mortality during active movement has received much attention, few have studied the costs of passive movement such as the airborne transport of fungal spores. Here, we examine the potential of extreme environmental conditions to cause dispersal mortality in wood-decay fungi. These fungi play a key role as decomposers and habitat creators in forest ecosystems and the populations of many species have declined due to habitat loss and fragmentation. We measured the effect of simulated solar radiation (including ultraviolet A and B) and freezing at −25°C on the spore germinability of 17 species. Both treatments but especially sunlight markedly reduced spore germinability in most species, and species with thin-walled spores were particularly light sensitive. Extrapolating the species' laboratory responses to natural irradiance conditions, we predict that sunlight is a relevant source of dispersal mortality at least at larger spatial scales. In addition, we found a positive effect of spore size on spore germinability, suggesting a trade-off between dispersal distance and establishment. We conclude that freezing and particularly sunlight can be important sources of dispersal mortality in wood-decay fungi which can make it difficult for some species to colonize isolated habitat patches and habitat edges. PMID:26380666

An experimental method to simulate incipient decay of wood basidiomycete fungi

Treesearch

Simon Curling; Jerrold E. Winandy; Carol A. Clausen

2000-01-01

At very early stages of decay of wood by basidiomycete fungi, strength loss can be measured from wood before any measurable weight loss. Therefore, strength loss is a more efficient measure of incipient decay than weight loss. However, common standard decay tests (e.g. EN 113 or ASTM D2017) use weight loss as the measure of decay. A method was developed that allowed...

Chapter 3: Wood Decay

Treesearch

Dan Cullen

2014-01-01

A significant portion of global carbon is sequestered in forest systems. Specialized fungi have evolved to efficiently deconstruct woody plant cell walls. These important decay processes generate litter, soil bound humic substances, or carbon dioxide and water. This chapter reviews the enzymology and molecular genetics of wood decay fungi, most of which are members of...

Control of wood decay by Trichoderma (Gliocladium virens. I, Antagonistic properties

Treesearch

T. L. Highley

1997-01-01

Antagonistic characteristics of a commercial biofungicide, Trichoderma (Gliocladiurn) virens (GL-21, W. R. Grace and Co., CT), were evaluated against three white-rot fungi, Trametes versicolor, Phlebia brevispora, Irpex lacteus, and three brown-rot fungi, Postia placenta, Neolentinus lepideus, and Gloeophyllum trabeum. In dual cultures of T. virens and wood decay fungi...

Comparative transcriptome and secretome analysis of wood decay fungi Postia placenta and Phanerochaete chrysosporium

Treesearch

Amber J. Vanden Wymelenberg; Jill Gaskell; Michael Mozuch; Grzegorz Sabat; John Ralph; Oleksandr Skyba; Shawn D Mansfield; Robert A. Blanchette; Diego Martinez; Igor Grigoriev; Philip J Kersten; Daniel Cullen

2010-01-01

Cellulose degradation by brown rot fungi, such as Postia placenta, is poorly understood relative to the phylogenetically related white rot basidiomycete, Phanerochaete chrysosporium. To elucidate the number, structure, and regulation of genes involved in lignocellulosic cell wall attack, secretome and transcriptome analyses were performed on both wood decay fungi...

Differences in crystalline cellulose modification due to degradation by brown and white rot fungi.

PubMed

Hastrup, Anne Christine Steenkjær; Howell, Caitlin; Larsen, Flemming Hofmann; Sathitsuksanoh, Noppadon; Goodell, Barry; Jellison, Jody

2012-10-01

Wood-decaying basidiomycetes are some of the most effective bioconverters of lignocellulose in nature, however the way they alter wood crystalline cellulose on a molecular level is still not well understood. To address this, we examined and compared changes in wood undergoing decay by two species of brown rot fungi, Gloeophyllum trabeum and Meruliporia incrassata, and two species of white rot fungi, Irpex lacteus and Pycnoporus sanguineus, using X-ray diffraction (XRD) and (13)C solid-state nuclear magnetic resonance (NMR) spectroscopy. The overall percent crystallinity in wood undergoing decay by M. incrassata, G. trabeum, and I. lacteus appeared to decrease according to the stage of decay, while in wood decayed by P. sanguineus the crystallinity was found to increase during some stages of degradation. This result is suggested to be potentially due to the different decay strategies employed by these fungi. The average spacing between the 200 cellulose crystal planes was significantly decreased in wood degraded by brown rot, whereas changes observed in wood degraded by the two white rot fungi examined varied according to the selectivity for lignin. The conclusions were supported by a quantitative analysis of the structural components in the wood before and during decay confirming the distinct differences observed for brown and white rot fungi. The results from this study were consistent with differences in degradation methods previously reported among fungal species, specifically more non-enzymatic degradation in brown rot versus more enzymatic degradation in white rot. Copyright © 2012 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Decay fungi associated with oaks and other hardwoods in the western United States

Treesearch

Jessie A. Glaeser; Kevin T. Smith

2010-01-01

An assessment of the presence and extent of the wood decay process should be part of any hazard tree analysis. Identification of the fungi responsible for decay improves both the prediction of the consequences of wood decay and the prescription of management options including tree pruning or removal. Until the outbreak of Sudden Oak Death (SOD), foresters in the...

Fungal accumulation of metals from building materials during brown rot wood decay.

PubMed

Hastrup, Anne Christine Steenkjær; Jensen, Bo; Jellison, Jody

2014-08-01

This study analyzes the accumulation and translocation of metal ions in wood during the degradation performed by one strain of each of the three brown rot fungi; Serpula lacrymans, Meruliporia incrassata and Coniophora puteana. These fungi species are inhabitants of the built environment where the prevention and understanding of fungal decay is of high priority. This study focuses on the influence of various building materials in relation to fungal growth and metal uptake. Changes in the concentration of iron, manganese, calcium and copper ions in the decayed wood were analyzed by induced coupled plasma spectroscopy and related to wood weight loss and oxalic acid accumulation. Metal transport into the fungal inoculated wood was found to be dependent on the individual strain/species. The S. lacrymans strain caused a significant increase in total iron whereas the concentration of copper ions in the wood appeared decreased after 10 weeks of decay. Wood inoculated with the M. incrassata isolate showed the contrary tendency with high copper accumulation and low iron increase despite similar weight losses for the two strains. However, significantly lower oxalic acid accumulation was recorded in M. incrassata degraded wood. The addition of a building material resulted in increased weight loss in wood degraded by C. puteana in the soil-block test; however, this could not be directly linked specifically to the accumulation of any of the four metals recorded. The accumulation of oxalic acid seemed to influence the iron uptake. The study assessing the influence of the presence of soil and glass in the soil-block test revealed that soil contributed the majority of the metals for uptake by the fungi and contributed to increased weight loss. The varying uptake observed among the three brown rot fungi strains toward the four metals analyzed may be related to the specific non-enzymatic and enzymatic properties including bio-chelators employed by each of the species during wood decay.

Wood-decay abilities of grapevine trunk pathogens Diaporthe ampelina, Diplodia seriata, Eutypa lata, and Neofusicoccum parvum

USDA-ARS?s Scientific Manuscript database

Trunk pathogens are fungi that infect grapevine wood through pruning wounds and destroy fruiting positions, thereby impacting grape production. Neofusicoccum parvum (causal fungus of Botryosphaeria dieback) and Eutypa lata (causal fungus of Eutypa dieback) cause chronic infections (cankers) of the t...

Correlation between oxalic acid production and copper tolerance in Wolfiporia cocos

Treesearch

C. A. Clausen; Frederick Green; B. M. Woodward; J. W. Evans; R. C. DeGroot

2000-01-01

The increased interest in copper-based wood preservatives has hastened the need for understanding why some fungi are able to attack copper-treated wood. Due in part to accumulation of oxalic acid by brown-rot fungi and visualization of copper oxalate crystals in wood decayed by known copper-tolerant decay fungi, oxalic acid has been implicated in copper tolerance by...

Inhibition of decay fungi using cotton cellulose hydrolysis as a model for wood decay

Treesearch

Frederick Green

2000-01-01

Environmental pressures to replace chromium and arsenic in fixed waterborne preservatives have been increasing. Potential inhibitors of brown-, white- and soft-rot fungi need to be evaluated as alternative preservatives by screening and testing in, in vitro model systems. This paper reports the inhibition of cellulose depolymerization and weight loss of selected decay...

Antimicrobial Decapeptide KSL-W Attenuates Candida albicans Virulence by Modulating Its Effects on Toll-Like Receptor, Human Beta-Defensin, and Cytokine Expression by Engineered human Oral Mucosa

DTIC Science & Technology

2011-02-02

against phytopathogenic fungi that cause postharvest decay in fruits . Mol Plant Microbe Interact 2000;13:837–46. [28] Montesinos E, Antimicrobial peptides...inactivated KSL-W did not affect epithelial cell proliferation (Fig. 2). 3.3. KSL-W pre-treatment reduced Candida growth in the infected oral mucosa tissue...against fungi , such as C. albi- cans, remains to be determined. Oral candidiasis is associatedwith gingival tissuewhere epithe- lial cells are the primary

An Antarctic hot spot for fungi at Shackleton's historic hut on Cape Royds.

PubMed

Blanchette, Robert A; Held, Benjamin W; Arenz, Brett E; Jurgens, Joel A; Baltes, Nicolas J; Duncan, Shona M; Farrell, Roberta L

2010-07-01

The historic expedition huts located in the Ross Sea Region of the Antarctic and the thousands of artifacts left behind by the early explorers represent important cultural heritage from the "Heroic Era" of Polar exploration. The hut at Cape Royds built by Ernest Shackleton and members of the 1907-1908 British Antarctic Expedition has survived the extreme Antarctic environment for over 100 years, but recent studies have shown many forms of deterioration are causing serious problems, and microbial degradation is evident in the historic wood. Conservation work to reduce moisture at the hut required removal of fodder, wood, and many different types of organic materials from the stables area on the north side of the structure allowing large numbers of samples to be obtained for these investigations. In addition, wood from historic food storage boxes exposed in a ravine adjacent to the hut were also sampled. Fungi were cultured on several different media, and pure cultures were obtained and identified by sequencing of the internal transcribed spacer region of rDNA. From the 69 cultures of filamentous fungi obtained, the most predominant genera were Cadophora (44%) followed by Thielavia (17%) and Geomyces (15%). Other fungi found included Cladosporium, Chaetomium, and isolates identified as being in Pezizomycotina, Onygenales, Nectriaceae, and others. No filamentous basidiomycetes were found. Phylogenetic analyses of the Cadophora species showed great species diversity present revealing Cadophora malorum, Cadophora luteo-olivacea, Cadophora fastigiata, as well as Cadophora sp. 4E71-1, a C. malorum-like species, and Cadophora sp. 7R16-1, a C. fastigiata-like species. Scanning electron microscopy showed extensive decay was present in the wood samples with type 1 and type 2 forms of soft rot evident in pine and birch wood, respectively. Fungi causing decay in the historic wooden structures and artifacts are of great concern, and this investigation provides insight into the identity and species diversity of fungi found at the site. The historic woods and other organic materials at this site represent a large input of carbon into the Antarctic environment. This as well as nutrient additions from the nearby Adélie penguin (Pygoscelis adeliae) colony and favorable conditions for fungal growth at Cape Royds appear responsible for the significant fungal diversity, and where extensive decay is taking place in wood in contact with the ground.

Decay resistance of wood treated with boric acid and tall oil derivates.

PubMed

Temiz, Ali; Alfredsen, Gry; Eikenes, Morten; Terziev, Nasko

2008-05-01

In this study, the effect of two boric acid concentrations (1% and 2%) and four derivates of tall oil with varying chemical composition were tested separately and in combination. The tall oil derivates were chosen in a way that they consist of different amounts of free fatty, resin acids and neutral compounds. Decay tests using two brown rot fungi (Postia placenta and Coniophora puteana) were performed on both unleached and leached test samples. Boric acid showed a low weight loss in test samples when exposed to fungal decay before leaching, but no effect after leaching. The tall oil derivates gave better efficacy against decay fungi compared to control, but are not within the range of the efficacy needed for a wood preservative. Double impregnation with boric acid and tall oil derivates gave synergistic effects for several of the double treatments both in unleached and leached samples. In the unleached samples the double treatment gave a better efficacy against decay fungi than tall oil alone. In leached samples a better efficacy against brown rot fungi were achieved than in samples with boron alone and a nearly similar or better efficacy than for tall oil alone. Boric acid at 2% concentration combined with the tall oil derivate consisting of 90% free resin acids (TO-III) showed the best performance against the two decay fungi with a weight loss less than 3% after a modified pure culture test.

Decay fungi of oaks and associated hardwoods for western arborists

Treesearch

Jessie A. Glaeser; Kevin T. Smith

2010-01-01

Examination of trees for the presence and extent of decay should be part of any hazard tree assessment. Identification of the fungi responsible for the decay improves prediction of tree performance and the quality of management decisions, including tree pruning or removal. Scouting for Sudden Oak Death (SOD) in the West has drawn attention to hardwood tree species,...

Wood decay fungi restore essential calcium to acidic soils in northern New England

Treesearch

Walter C. Shortle; Kevin T. Smith

2015-01-01

The depletion of root-available calcium in northern forests soils exposed to decades of increased acid deposition adversely affects forest health and productivity. Laboratory studies indicated the potential of wood-decay fungi to restore lost calcium to the rooting zone of trees. This study reports changes in concentrations of Ca, Mg, and K during decay of sapwood of...

Use of cyclodextrin-based polymer for patulin analysis in apple juice

USDA-ARS?s Scientific Manuscript database

Penicillium expansum, one of the patulin producing fungi that causes decay on apple, is recognized as the main source of patulin contamination on apple and apple products. The widely used method for patulin analysis in apple juice is liquid-liquid extraction with ethyl acetate followed by HPLC-UV or...

Distinctive Expansion of Gene Families Associated with Virulence Functions in the Genomes of Grapevine Trunk Pathogens

USDA-ARS?s Scientific Manuscript database

Trunk diseases are responsible for important economic losses in all viticulture production systems. They are caused by distantly-related fungi that form chronic wood infections. Variation in wood-decay abilities and production of phytotoxic compounds are thought to contribute to differences in the d...

Comparative genome analysis of Basidiomycete fungi

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riley, Robert; Salamov, Asaf; Henrissat, Bernard

Fungi of the phylum Basidiomycota (basidiomycetes), make up some 37percent of the described fungi, and are important in forestry, agriculture, medicine, and bioenergy. This diverse phylum includes symbionts, pathogens, and saprotrophs including the majority of wood decaying and ectomycorrhizal species. To better understand the genetic diversity of this phylum we compared the genomes of 35 basidiomycetes including 6 newly sequenced genomes. These genomes span extremes of genome size, gene number, and repeat content. Analysis of core genes reveals that some 48percent of basidiomycete proteins are unique to the phylum with nearly half of those (22percent) found in only one organism.more » Correlations between lifestyle and certain gene families are evident. Phylogenetic patterns of plant biomass-degrading genes in Agaricomycotina suggest a continuum rather than a dichotomy between the white rot and brown rot modes of wood decay. Based on phylogenetically-informed PCA analysis of wood decay genes, we predict that that Botryobasidium botryosum and Jaapia argillacea have properties similar to white rot species, although neither has typical ligninolytic class II fungal peroxidases (PODs). This prediction is supported by growth assays in which both fungi exhibit wood decay with white rot-like characteristics. Based on this, we suggest that the white/brown rot dichotomy may be inadequate to describe the full range of wood decaying fungi. Analysis of the rate of discovery of proteins with no or few homologs suggests the value of continued sequencing of basidiomycete fungi.« less

Production of polygalacturonase and increase of longitudinal gas permeability in southern pine by brown-rot and white-rot fungi

Treesearch

Frederick Green; Carol A. Clausen

1999-01-01

Hydrolysis of bordered and pinoid pits may be a key event during colonization of wood by decay fungi. Although pits are numerous, studies of pectin-hydrolyzing enzymes in wood decay fungi are scarce, probably because of the relatively low content (less than 4 %) of pectin in wood and because of the primary focus on understanding the degradation of lignified components...

Characteristics of ten tropical hardwoods from certified forests in Bolivia. Part II, Natural durability to decay fungi

Treesearch

Regis B. Miller; Alex C. Wiedenhoeft; R. Sam Williams; Willy Stockman; Frederick Green

2003-01-01

The natural durability of 10 lesser known, commercially available Bolivian hardwoods to decay fungi was evaluated using a modified ASTM soil-block analysis for 12 weeks. The blocks were then retested for an additional 12 weeks to determine their level of decay resistance, as determined by percentage of weight loss. Astronium urundeuva, Caesalpinia cf. pluviosa,...

Extensive sampling of basidiomycete genomes demonstrates inadequacy of the white-rot/brown-rot paradigm for wood decay fungi

Treesearch

Robert Riley; Asaf A. Salamov; Daren W. Brown; Laszlo G. Nagy; Dimitrios Floudas; Benjamin W. Held; Anthony Levasseur; Vincent Lombard; Emmanuelle Morin; Robert Otillar; Erika A. Lindquist; Hui Sun; Kurt M. LaButti; Jeremy Schmutz; Dina Jabbour; Hong Luo; Scott E. Baker; Antonio G. Pisabarro; Jonathan D. Walton; Robert A. Blanchette; Bernard Henrissat; Francis Martin; Daniel Cullen; David S. Hibbett; Igor V. Grigoriev

2014-01-01

Basidiomycota (basidiomycetes) make up 32% of the described fungi and include most wood-decaying species, as well as pathogens and mutualistic symbionts. Wood-decaying basidiomycetes have typically been classified as either white rot or brown rot, based on the ability (in white rot only) to degrade lignin along with cellulose and hemicellulose. Prior genomic...

Syringyl-rich lignin renders poplars more resistant to degradation by wood decay fungi.

PubMed

Skyba, Oleksandr; Douglas, Carl J; Mansfield, Shawn D

2013-04-01

In order to elucidate the effects of lignin composition on the resistance of wood to degradation by decay fungi, wood specimens from two transgenic poplar lines expressing an Arabidopsis gene encoding ferulate 5-hydroxylase (F5H) driven by the cinnimate-4-hydroxylase promoter (C4H::F5H) that increased syringyl/guaiacyl (S/G) monolignol ratios relative to those in the untransformed control wood were incubated with six different wood decay fungi. Alterations in wood weight and chemical composition were monitored over the incubation period. The results showed that transgenic poplar lines extremely rich in syringyl lignin exhibited a drastically improved resistance to degradation by all decay fungi evaluated. Lignin monomer composition and its distribution among cell types and within different cell layers were the sole wood chemistry parameters determining wood durability. Since transgenic poplars with exceedingly high syringyl contents were recalcitrant to degradation, where wood durability is a critical factor, these genotypes may offer improved performance.

Syringyl-Rich Lignin Renders Poplars More Resistant to Degradation by Wood Decay Fungi

PubMed Central

Skyba, Oleksandr; Douglas, Carl J.

2013-01-01

In order to elucidate the effects of lignin composition on the resistance of wood to degradation by decay fungi, wood specimens from two transgenic poplar lines expressing an Arabidopsis gene encoding ferulate 5-hydroxylase (F5H) driven by the cinnimate-4-hydroxylase promoter (C4H::F5H) that increased syringyl/guaiacyl (S/G) monolignol ratios relative to those in the untransformed control wood were incubated with six different wood decay fungi. Alterations in wood weight and chemical composition were monitored over the incubation period. The results showed that transgenic poplar lines extremely rich in syringyl lignin exhibited a drastically improved resistance to degradation by all decay fungi evaluated. Lignin monomer composition and its distribution among cell types and within different cell layers were the sole wood chemistry parameters determining wood durability. Since transgenic poplars with exceedingly high syringyl contents were recalcitrant to degradation, where wood durability is a critical factor, these genotypes may offer improved performance. PMID:23396333

[Bacterium Arthrobacter agilis UMCV2 and diverse amines inhibit in vitro growth of wood-decay fungi].

PubMed

Orozco-Mosqueda, M Del Carmen; Valencia-Cantero, Eduardo; López-Albarrán, Pablo; Martínez-Pacheco, Mauro; Velázquez-Becerra, Crisanto

2015-01-01

The kingdom Fungi is represented by a large number of organisms, including pathogens that deteriorate the main structural components of wood, such as cellulose, hemicellulose and lignin. The aim of our work was to characterize the antifungal activity in Arthrobacter agilis UMCV2 and diverse amines against wood-decaying fungi. Four fungal organisms (designated as UMTM) were isolated from decaying wood samples obtained from a forest in Cuanajo-Michoacán, México. Two of them showed a clear enzymatic activity of cellulases, xylanases and oxido-reducing enzymes and were identified as Hypocrea (UMTM3 isolate) and Fusarium (UMTM13 isolate). In vitro, the amines showed inhibitory effect against UMTM growth and one of the amines, dimethylhexadecylamine (DMA16), exhibited strong potential as wood preventive treatment, against the attack of decaying fungi. Copyright © 2015 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Wood decay: a submicroscopic view

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blanchette, R.A.

1980-01-01

Typical patterns of decay in softwoods are shown by ultrastructural differences revealed by SEM. Illustrative micrographs are reproduced showing fungi and their effects. Brown rot fungi (e.g. Fomitopsis pinicolor) degrade cellulose leaving a lignin skeleton. White rot fungi (e.g. Coriolus versicolor and Hirschioporus abietinus) degrade both lignin and cellulose. White pocket rots (e.g. Phellinus pini) primarily degrade lignin; they have potential for use in paper making, or the production of animal feed.

Diversity and decay ability of basidiomycetes isolated from lodgepole pines killed by the mountain pine beetle.

PubMed

Son, E; Kim, J-J; Lim, Y W; Au-Yeung, T T; Yang, C Y H; Breuil, C

2011-01-01

When lodgepole pines (Pinus contorta Douglas ex Louden var. latifolia Engelm. ex S. Watson) that are killed by the mountain pine beetle (Dendroctonus ponderosae) and its fungal associates are not harvested, fungal decay can affect wood and fibre properties. Ophiostomatoids stain sapwood but do not affect the structural properties of wood. In contrast, white or brown decay basidiomycetes degrade wood. We isolated both staining and decay fungi from 300 lodgepole pine trees killed by mountain pine beetle at green, red, and grey stages at 10 sites across British Columbia. We retained 224 basidiomycete isolates that we classified into 34 species using morphological and physiological characteristics and rDNA large subunit sequences. The number of basidiomycete species varied from 4 to 14 species per site. We assessed the ability of these fungi to degrade both pine sapwood and heartwood using the soil jar decay test. The highest wood mass losses for both sapwood and heartwood were measured for the brown rot species Fomitopsis pinicola and the white rot Metulodontia and Ganoderma species. The sap rot species Trichaptum abietinum was more damaging for sapwood than for heartwood. A number of species caused more than 50% wood mass losses after 12 weeks at room temperature, suggesting that beetle-killed trees can rapidly lose market value due to degradation of wood structural components.

Bacteria in decomposing wood and their interactions with wood-decay fungi.

PubMed

Johnston, Sarah R; Boddy, Lynne; Weightman, Andrew J

2016-11-01

The fungal community within dead wood has received considerable study, but far less attention has been paid to bacteria in the same habitat. Bacteria have long been known to inhabit decomposing wood, but much remains underexplored about their identity and ecology. Bacteria within the dead wood environment must interact with wood-decay fungi, but again, very little is known about the form this takes; there are indications of both antagonistic and beneficial interactions within this fungal microbiome. Fungi are hypothesised to play an important role in shaping bacterial communities in wood, and conversely, bacteria may affect wood-decay fungi in a variety of ways. This minireview considers what is currently known about bacteria in wood and their interactions with fungi, and proposes possible associations based on examples from other habitats. It aims to identify key knowledge gaps and pressing questions for future research. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Multidimensional NMR analysis reveals truncated lignin structures in wood decayed by the brown rot basidiomycete Postia placenta

Treesearch

Daniel J. Yelle; Dongsheng Wei; John Ralph; Kenneth E. Hammel

2011-01-01

Lignocellulose biodegradation, an essential step in terrestrial carbon cycling, generally involves removal of the recalcitrant lignin barrier that otherwise prevents infiltration by microbial polysaccharide hydrolases. However, fungi that cause brown rot of wood, a major route for biomass recycling in coniferous forests, utilize wood polysaccharides efficiently while...

Distinctive expansion of gene families associated with plant cell wall degradation, secondary metabolism, and nutrient uptake in the genomes of grapevine trunk pathogens

USDA-ARS?s Scientific Manuscript database

Trunk diseases threaten the longevity and productivity of grapevines in all viticulture production systems. They are caused by distantly-related fungi that form chronic wood infections, but variation in wood-decay abilities and production of phytotoxic compounds are thought to contribute to their un...

[Isolation of wood-decaying fungi and evaluation of their enzymatic activity (Quindío, Colombia)].

PubMed

Chaparro, Deisy Fernanda; Rosas, Diana Carolina; Varela, Amanda

2009-12-31

White rot fungi (Ascomycota and Basidiomycota) were collected on fallen trunks with different decay stages, in a subandean forest (La Montaña del Ocaso nature reserve), and it was evaluated their ligninolitic activity. They were cultured on malt extract agar. Then it was performed semiquantitative tests for laccase and cellobiose dehydrogenase (CDH) activity using ABTS and DCPIP as enzymatic inducers. Based on the results of these tests, the fungi with higher activities from trunks with different decay stages were selected: Cookeina sulcipes (for stage 1), a fungus from the family Corticiaceae (for stage 2), Xylaria polymorpha (for stage 3) and Earliella sp. (for stage 4). A fermentation was performed at 28 degrees C, during 11 days, in a rotatory shaker at 150 rpm. Biomass, glucose, proteins and enzyme activities measurements were performed daily. The fungi that were in the trunks with decay states from 1 to 3, showed higher laccase activity as the state of decay increased. A higher DCH activity was also associated with a higher. Also, there was a positive relationship between both enzymes' activities. Erliella was the fungus which presented the highest biomass production (1140,19 g/l), laccase activity (157 UL(-1)) and CDH activity (43,50 UL(-1)). This work is the first report of laccase and CDH activity for Cookeina sulcipes and Earliella sp. Moreover, it gives basis for the use of these native fungi in biotechnological applications and the acknowledgment of their function in the wood decay process in native forest.

Aggregation and feeding behavior of the formosan subterranean termite (Isoptera: Rhinotermitidae) on wood decayed by three species of wood rot fungi

USDA-ARS?s Scientific Manuscript database

Aggregation and feeding behavior of the Formosan subterranean termite, Coptotermes formosanus Shiraki, was evaluated on wood decayed by three species of fungus that use different enzymatic pathways to degrade lignocellulose, the brown rot fungus, Gloeophyllum trabeum and two white rot fungi, Phanero...

A multiplex PCR-based method for the detection and early identification of wood rotting fungi in standing trees.

PubMed

Guglielmo, F; Bergemann, S E; Gonthier, P; Nicolotti, G; Garbelotto, M

2007-11-01

The goal of this research was the development of a PCR-based assay to identify important decay fungi from wood of hardwood tree species in northern temperate regions. Eleven taxon-specific primers were designed for PCR amplification of either nuclear or mitochondrial ribosomal DNA regions of Armillaria spp., Ganoderma spp., Hericium spp., Hypoxylon thouarsianum var. thouarsianum, Inonotus/Phellinus-group, Laetiporus spp., Perenniporia fraxinea, Pleurotus spp., Schizophyllum spp., Stereum spp. and Trametes spp. Multiplex PCR reactions were developed and optimized to detect fungal DNA and identify each taxon with a sensitivity of at least 1 pg of target DNA in the template. This assay correctly identified the agents of decay in 82% of tested wood samples. The development and optimization of multiplex PCRs allowed for reliable identification of wood rotting fungi directly from wood. Early detection of wood decay fungi is crucial for assessment of tree stability in urban landscapes. Furthermore, this method may prove useful for prediction of the severity and the evolution of decay in standing trees.

SEM study of the effects of bacteria and yeasts on wood decay by brown and white-rot fungi. [Enterobacter, Cryptococcus Pichia, and Saccharomyces

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blanchette, R.A.; Shaw, C.G.; Cohen, A.L.

The scanning electron microscope was used to 1) examine the associations among microorganisms during wood decay and 2) observe the effect of these organisms on degradation of cell wall components. Bacteria (Enterobacter) and yeasts (Cryptococcus Pichia, and Saccharomyces) were found to have a mutualistic association with a white-rot fungus during decay of coniferous wood. Coriolus (Polyporus versicolar) degraded cell wall components in a typical ''erosion trough'' manner (i.e., by lysing zones around fungal hyphae). Bacteria and yeasts were seen only in these lysed zones. Typical gross decay patterns caused by the white-rot fungus were unaltered by bacteria and yeasts. Themore » SEM study suggests that the decay process is enhanced when these organisms are associated. In contrast, the same bacteria and yeasts were inhibitory when combined with a brown-rot fungus.« less

Simulated nitrogen deposition affects wood decomposition by cord-forming fungi.

PubMed

Bebber, Daniel P; Watkinson, Sarah C; Boddy, Lynne; Darrah, Peter R

2011-12-01

Anthropogenic nitrogen (N) deposition affects many natural processes, including forest litter decomposition. Saprotrophic fungi are the only organisms capable of completely decomposing lignocellulosic (woody) litter in temperate ecosystems, and therefore the responses of fungi to N deposition are critical in understanding the effects of global change on the forest carbon cycle. Plant litter decomposition under elevated N has been intensively studied, with varying results. The complexity of forest floor biota and variability in litter quality have obscured N-elevation effects on decomposers. Field experiments often utilize standardized substrates and N-levels, but few studies have controlled the decay organisms. Decomposition of beech (Fagus sylvatica) blocks inoculated with two cord-forming basidiomycete fungi, Hypholoma fasciculare and Phanerochaete velutina, was compared experimentally under realistic levels of simulated N deposition at Wytham Wood, Oxfordshire, UK. Mass loss was greater with P. velutina than with H. fasciculare, and with N treatment than in the control. Decomposition was accompanied by growth of the fungal mycelium and increasing N concentration in the remaining wood. We attribute the N effect on wood decay to the response of cord-forming wood decay fungi to N availability. Previous studies demonstrated the capacity of these fungi to scavenge and import N to decaying wood via a translocating network of mycelium. This study shows that small increases in N availability can increase wood decomposition by these organisms. Dead wood is an important carbon store and habitat. The responses of wood decomposers to anthropogenic N deposition should be considered in models of forest carbon dynamics.

Mechanisms of protection by NHA against fungal decay

Treesearch

Frederick Green; William Henry; Tor Schultz

2002-01-01

Treating wood with the water-borne sodium salt of N'-N-naphthaloylhydroxylamine (Na-NHA) protects wood against decay and termite damage. Initial testing indicated little or no inhibition of sapstain fungi, molds, or soft-rot fungi by Na-NHA, suggesting that the mechanism by which this compound protected wood was complex and not that of a broad-spectrum biocide....

Bioprocessing preservative-treated waste wood

Treesearch

Barbara L. Illman; Vina W. Yang; Les Ferge

2000-01-01

Disposal of preservative-treated waste wood is a growing problem worldwide. Bioprocessing the treated wood offers one approach to waste management under certain conditions. One goal is to use wood decay fungi to reduce the volume of waste with an easily managed system in a cost-effective manner. Wood decay fungi were obtained from culture collections in the Mycology...

Inhibition and stimulation effects in communities of wood decay fungi: exudates from colonized wood influence growth by other species.

PubMed

Heilmann-Clausen, J; Boddy, L

2005-04-01

The effects of exudates from uncolonized and from partly decayed beech wood on the extension rates of 16 later stage decay fungi were investigated. The partly decayed wood had been colonized by the pyrenomycete Eutypa spinosa, or the basidiomycetes Fomes fomentarius, Stereum hirsutum, and Trametes versicolor, all known as common early decay agents in European beech forests. Sterilized wood pieces were placed onto 0.5% malt agar, opposite to small agar plugs containing the test fungi. The latter showed very variable and species-specific growth responses to the various wood types. The presence of uncolonized wood stimulated extension rates in many species, whereas the four previously decayed wood types had variable stimulatory or inhibitory effects. Wood decayed by S. hirsutum resulted in reduced extension rate, delayed growth, or total inhibition in the majority of species, thus it is suggested that this species uses secondary metabolites in a defensive strategy. A single species was, however, stimulated in the presence of S. hirsutum-decayed wood. In contrast, the presence of wood decayed by F. fomentarius was stimulatory to 45% of the species. The other previously decayed wood types generally resulted in more variable responses, depending upon species. The results are discussed in an ecological context and it is suggested that the exudates from the partly decayed wood that are responsible for the reported effects may function as infochemicals, structuring microbial communities in wood.

Observation and identification of wood decay fungi from the heartwood of peach tree limbs in central Georgia, USA

USDA-ARS?s Scientific Manuscript database

Peach tree health, longevity, and limb strength can be affected by wood decay fungi, but the extent of the colonization and their identities have not been characterized in Georgia, the United States of America. In an incubation experiment, dense white fungal mycelium grew on the cross-cut faces of a...

Significant alteration of gene expression in wood decay fungi Postia placenta and Phanerochaete chrysosporium by plant species

Treesearch

Amber Vanden Wymelenberg; Jill Gaskell; Michael Mozuch; Sandra Splinter BonDurant; Grzegorz Sabat; John Ralph; Oleksandr Skyba; Shawn D. Mansfield; Robert A. Blanchette; Igor Grigoriev; Philip J. Kersten; Daniel Cullen

2011-01-01

Identification of specific genes and enzymes involved in conversion of lignocellulosics from an expanding number of potential feedstocks is of growing interest to bioenergy process development. The basidiomycetous wood decay fungi Phanerochaete chrysosporium and Postia placenta are promising in this regard because they are able to utilize a wide range of simple and...

Activity of two strobilurin fungicides against three species of decay fungi in agar plate tests

Treesearch

Juliet D. Tang; Tina Ciaramitaro; Maria Tomaso-Peterson; Susan V. Diehl

2017-01-01

The objective of this study was to examine the toxicity of strobilurin fungicides against wood decay fungi in order to assess their potential to act as a co-biocide for copper-based wood protection. Two strobilurin fungicides, Heritage (50% azoxystrobin active ingredient) and Insignia (20% pyraclostrobin active ingredients), and copper sulfate pentahydrate were tested...

Effects of pex1 disruption on wood lignin biodegradation, fruiting development and the utilization of carbon sources in the white-rot Agaricomycete Pleurotus ostreatus and non-wood decaying Coprinopsis cinerea.

PubMed

Nakazawa, Takehito; Izuno, Ayako; Horii, Masato; Kodera, Rina; Nishimura, Hiroshi; Hirayama, Yuichiro; Tsunematsu, Yuta; Miyazaki, Yasumasa; Awano, Tatsuya; Muraguchi, Hajime; Watanabe, Kenji; Sakamoto, Masahiro; Takabe, Keiji; Watanabe, Takashi; Isagi, Yuji; Honda, Yoichi

2017-12-01

Peroxisomes are well-known organelles that are present in most eukaryotic organisms. Mutant phenotypes caused by the malfunction of peroxisomes have been shown in many fungi. However, these have never been investigated in Agaricomycetes, which include white-rot fungi that degrade wood lignin in nature almost exclusively and play an important role in the global carbon cycle. Based on the results of a forward genetics study to identify mutations causing defects in the ligninolytic activity of the white-rot Agaricomycete Pleurotus ostreatus, we report phenotypes of pex1 disruptants in P. ostreatus, which are defective in two major features of white-rot Agaricomycetes: lignin biodegradation and mushroom formation. Pex1 disruption was also shown to cause defects in the hyphal growth of P. ostreatus on certain sawdust and minimum media. We also demonstrated that pex1 is essential for fruiting initiation in the non-wood decaying Agaricomycete Coprinopsis cinerea. However, unlike P. ostreatus, significant defects in hyphal growth on the aforementioned agar medium were not observed in C. cinerea. This result, together with previous C. cinerea genetic studies, suggests that the regulation mechanisms for the utilization of carbon sources are altered during the evolution of Agaricomycetes or Agaricales. Copyright © 2017 Elsevier Inc. All rights reserved.

Twenty-second Fungal Genetics Conference - Asilomar, 2003

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jonathan D. Walton

The purpose of the Twenty Second Fungal Genetics Conference is to bring together scientists and students who are interested in genetic approaches to studying the biology of filamentous fungi. It is intended to stimulate thinking and discussion in an atmosphere that supports interactions between scientists at different levels and in different disciplines. Topics range from the basic to the applied. Filamentous fungi impact human affairs in many ways. In the environment they are the most important agents of decay and nutrient turnover. They are used extensively in the food industry for the production of food enzymes such as pectinase andmore » food additives such as citric acid. They are used in the production of fermented foods such as alcoholic drinks, bread, cheese, and soy sauce. More than a dozen species of mushrooms are used as foods directly. Many of our most important antibiotics, such as penicillin, cyclosporin, and lovastatin, come from fungi. Fungi also have many negative impacts on human health and economics. Fungi are serious pathogens in immuno-compromised patients. Fungi are the single largest group of plant pathogens and thus a serious limit on crop productivity throughout the world. Many fungi are allergenic, and mold contamination of residences and commercial buildings is now recognized as a serious public health threat. As decomposers, fungi cause extensive damage to just about all natural and synthetic materials.« less

Copper tolerance of brown-rot fungi : time course of oxalic acid production

Treesearch

Frederick Green; Carol A. Clausen

2003-01-01

The increase in the use of non-arsenical copper-based wood preservatives in response to environmental concerns has been accompanied by interest in copper-tolerant decay fungi. Oxalic acid production by brown-rot fungi has been proposed as one mechanism of copper tolerance. Fifteen brown-rot fungi representing the genera Postia, Wolfiporia, Meruliporia, Gloeophyllum,...

Molecular genetics of lignin-degrading fungi and their applications in organopollutant degradation

Treesearch

Daniel Cullen

2002-01-01

This chapter provides an overview of the physiology and associated molecular genetics of wood- decaying fungi as they relate to organopollutant degradation. White-rot fungi are characterized by an ability to fragment all major structural polymers of wood including lignin. More poorly understood are the brown-rot fungi, which rapidly depolymerize cellulosic materials...

A study of overproduction and enhanced secretion of enzymes. Quarterly report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dashek, W.V.

1993-09-01

Wood decay within forests, a significant renewable photosynthetic energy resource, is caused primarily by Basidiomycetous fungi, e.g., white rot fungi. These organisms possess the ability to degrade lignin, cellulose and hemicellulose, the main organic polymers of wood. In the case of the white rot fungi, e.g., Coriolus versicolor, the capacity results from the fungus` ability to elaborate extracellular cellulolytic and ligninolytic enzymes. With regard to the latter, at least one of the enzymes, polyphenol oxidase (PPO) appears within a defined growth medium. This proposal focuses on the over-production and enhanced secretion of PPO, cellulase and lignin peroxidase. There are twomore » major sections to the proposal: (1) overproduction of lignocellulolytic enzymes by genetic engineering methodologies and hyper-production and enhanced secretion of these enzymes by biochemical/electro microscopical techniques and (2) the biochemical/electron microscopical method involves substrate induction and the time-dependent addition of respiration and PPO enzymes.« less

Investigations of fungal diversity in wooden structures and soils at historic sites on the Antarctic Peninsula.

PubMed

Arenz, Brett E; Blanchette, Robert A

2009-01-01

Investigations of microbial diversity in Antarctic are important to begin to understand ecosystem functioning and decomposition processes. This study documents fungi at 9 historic sites on the Antarctic Peninsula collected from wooden structures, other organic materials, and soils during a joint National Science Foundation and British Antarctic Survey expedition in 2007. Many of these sites had wooden structures built by the British during the World War II Operation Tabarin, but others visited included the American "East Base" on Stonington Island and the Swedish hut on Snow Hill Island. Fungi were cultured on several different media and pure cultures were obtained and identified by DNA sequencing of the internal transcribed spacer region. Cadophora species previously found to attack historic wooden structures on Ross Island, Antarctica, were found at all but 1 location sampled in the Peninsula region. Fungi causing decay in the historic wooden structures and artifacts and those causing mold problems inside the structures are of great concern, and conservation efforts are urgently needed to help preserve these important polar heritage structures. The results presented also expand our knowledge on the identity of fungi present throughout the Antarctic Peninsula region and provide insights into the organisms responsible for decomposition and nutrient recycling.

How to Make a Beetle Out of Wood: Multi-Elemental Stoichiometry of Wood Decay, Xylophagy and Fungivory

PubMed Central

Filipiak, Michał; Weiner, January

2014-01-01

The majority of terrestrial biomass is wood, but the elemental composition of its potential consumers, xylophages, differs hugely from that of wood. This causes a severe nutritional imbalance. We studied the stoichiometric relationships of 11 elements (C, N, P, K, Ca, Mg, Fe, Zn, Mn, Cu, Na) in three species of pine-xylem-feeding insects, Stictoleptura rubra, Arhopalus rusticus (Coleoptera, Cerambycidae) and Chalcophora mariana (Coleoptera, Buprestidae), to elucidate their mechanisms of tissue growth and to match their life histories to their dietary constraints. These beetles do not differ from other Coleoptera in their absolute elemental compositions, which are approximately 1000 (N), 100 (P, Cu) and 50 (K, Na) times higher than in dead but undecayed pine wood. This discrepancy diminishes along the wood decay gradient, but the elemental concentrations remain higher by an order of magnitude in beetles than in highly decayed wood. Numerical simulation of the life history of S. rubra shows that feeding on nutrient-poor undecayed wood would extend its development time to implausible values, whereas feeding on highly decomposed wood (heavily infected with fungi) would barely balance its nutritional budget during the long development period of this species. The changes in stoichiometry indicate that the relative change in the nutrient levels in decaying wood cannot be attributed solely to carbon loss resulting from decomposer respiration: the action of fungi substantially enriches the decaying wood with nutritional elements imported from the outside of the system, making it a suitable food for wood-eating invertebrates. PMID:25536334

How to make a beetle out of wood: multi-elemental stoichiometry of wood decay, xylophagy and fungivory.

PubMed

Filipiak, Michał; Weiner, January

2014-01-01

The majority of terrestrial biomass is wood, but the elemental composition of its potential consumers, xylophages, differs hugely from that of wood. This causes a severe nutritional imbalance. We studied the stoichiometric relationships of 11 elements (C, N, P, K, Ca, Mg, Fe, Zn, Mn, Cu, Na) in three species of pine-xylem-feeding insects, Stictoleptura rubra, Arhopalus rusticus (Coleoptera, Cerambycidae) and Chalcophora mariana (Coleoptera, Buprestidae), to elucidate their mechanisms of tissue growth and to match their life histories to their dietary constraints. These beetles do not differ from other Coleoptera in their absolute elemental compositions, which are approximately 1000 (N), 100 (P, Cu) and 50 (K, Na) times higher than in dead but undecayed pine wood. This discrepancy diminishes along the wood decay gradient, but the elemental concentrations remain higher by an order of magnitude in beetles than in highly decayed wood. Numerical simulation of the life history of S. rubra shows that feeding on nutrient-poor undecayed wood would extend its development time to implausible values, whereas feeding on highly decomposed wood (heavily infected with fungi) would barely balance its nutritional budget during the long development period of this species. The changes in stoichiometry indicate that the relative change in the nutrient levels in decaying wood cannot be attributed solely to carbon loss resulting from decomposer respiration: the action of fungi substantially enriches the decaying wood with nutritional elements imported from the outside of the system, making it a suitable food for wood-eating invertebrates.

Substrate-Specific Differential Gene Expression and RNA editing in the Brown Rot Fungus Fomitopsis pinicola.

PubMed

Wu, Baojun; Gaskell, Jill; Held, Benjamin W; Toapanta, Cristina; Vuong, Thu; Ahrendt, Steven; Lipzen, Anna; Zhang, Jiwei; Schilling, Jonathan S; Master, Emma; Grigoriev, Igor V; Blanchette, Robert A; Cullen, Dan; Hibbett, David S

2018-06-08

Wood-decaying fungi tend to have characteristic substrate ranges that partly define their ecological niche. Fomitopsis pinicola is a brown rot species of Polyporales that is reported on 82 species of softwoods and 42 species of hardwoods. We analyzed gene expression levels and RNA editing profiles of F. pinicola from submerged cultures with ground wood powder (sampled at five days) or solid wood wafers (sampled at ten and thirty days), using aspen, pine, and spruce substrates (aspen was used only in submerged cultures). Fomitopsis pinicola expressed similar sets of wood-degrading enzymes typical of brown rot fungi across all culture conditions and timepoints. Nevertheless, differential gene expression and RNA editing were observed across all pairwise comparisons of substrates and timepoints. Genes exhibiting differential expression and RNA editing encode diverse enzymes with known or potential function in brown rot decay, including laccase, benzoquinone reductase, aryl alcohol oxidase, cytochrome P450s, and various glycoside hydrolases. There was no overlap between differentially expressed and differentially edited genes, suggesting that these may provide F. pinicola with independent mechanisms for responding to different conditions. Comparing transcriptomes from submerged cultures and wood wafers, we found that culture conditions had a greater impact on global expression profiles than substrate wood species. In contrast, the suites of genes subject to RNA editing were much less affected by culture conditions. These findings highlight the need for standardization of culture conditions in studies of gene expression in wood-decaying fungi. IMPORTANCE All species of wood-decaying fungi occur on a characteristic range of substrates (host plants), which may be broad or narrow. Understanding the mechanisms that allow fungi to grow on particular substrates is important for both fungal ecology and applied uses of different feedstocks in industrial processes. We grew the wood-decaying polypore Fomitopsis pinicola on three different wood species, aspen, pine and spruce, under various culture conditions. We examined both gene expression (transcription levels) and RNA editing (post-transcriptional modification of RNA, which can potentially yield different proteins from the same gene). We found that F. pinicola is able to modify both gene expression and RNA editing profiles across different substrate species and culture conditions. Many of the genes involved encode enzymes with known or predicted functions in wood decay. This work provides clues to how wood-decaying fungi may adjust their arsenal of decay enzymes to accommodate different host substrates. Copyright © 2018 American Society for Microbiology.

Tested Studies for Laboratory Teaching. Proceedings. Workshop/Conference of the Association for Biology Laboratory Education (ABLE) (11th, Fredericton, New Brunswick, Canada, June 12-16, 1989). Volume 11.

ERIC Educational Resources Information Center

Goldman, Corey A., Ed.

The focus of the Association for Biology Laboratory Education (ABLE) is to improve the undergraduate biology laboratory experience by promoting the development and dissemination of interesting, innovative, and reliable laboratory exercises. This proceedings volume contains 10 papers: "Investigating Fungi Which Cause Rot and Decay" (J. A Johnson);…

Decay of wood and wood-based products above ground in buildings

Treesearch

Charles G. Carll; Terry L. Highley

1999-01-01

This paper is an overview of what we know about occurrence of wood decay above ground within buildings. It presents information concerning under what conditions decay may become established. In laboratory tests involving optimum moisture and temperature conditions for decay fungi, and direct contact with large quantities of specific well-developed decay...

Spatial Heterogeneity of SOM Concentrations Associated with White-rot Versus Brown-rot Wood Decay.

PubMed

Bai, Zhen; Ma, Qiang; Dai, Yucheng; Yuan, Haisheng; Ye, Ji; Yu, Wantai

2017-10-23

White- and brown-rot fungal decay via distinct pathways imparts characteristic molecular imprints on decomposing wood. However, the effect that a specific wood-rotting type of fungus has on proximal soil organic matter (SOM) accumulation remains unexplored. We investigated the potential influence of white- and brown-rot fungi-decayed Abies nephrolepis logs on forest SOM stocks (i.e., soil total carbon (C) and nitrogen (N)) and the concentrations of amino sugars (microbial necromass) at different depths and horizontal distances from decaying woody debris. The brown-rot fungal wood decay resulted in higher concentrations of soil C and N and a greater increase in microbial necromass (i.e., 1.3- to 1.7-fold greater) than the white-rot fungal wood decay. The white-rot sets were accompanied by significant differences in the proportions of the bacterial residue index (muramic acid%) with soil depth; however, the brown-rot-associated soils showed complementary shifts, primarily in fungal necromass, across horizontal distances. Soil C and N concentrations were significantly correlated with fungal rather than bacterial necromass in the brown-rot systems. Our findings confirmed that the brown-rot fungi-dominated degradation of lignocellulosic residues resulted in a greater SOM buildup than the white-rot fungi-dominated degradation.

Hexadecyl ammonium chloride amylose inclusion complex to emulsify cedarwood oil and treat wood against termites and wood-decay fungi

Treesearch

F.J. Eller; W.T. Hay; G.T. Kirker; M.E. Mankowski; G.W. Sellling

2018-01-01

Cedarwood oil (CWO) has a wide range of bioactivities, including insect repellency and toxicity, as well as conferring resistance against termites and wood-decay fungi. In previous work examining pressure treatment of wood, ethanol was used as the diluent/carrier for CWO. However, it is preferable to use a water-based carrier for environmental, safety and cost...

Analysis of D-glucose metabolism of wood decay fungi using 13C-NMR and 13C-labeled substrates

Treesearch

Theodorus H. de Koker; Michael D. Mozuch; Philip J. Kersten

2003-01-01

D-Glucose metabolism is thought to be important during wood decay by fungi, not only for anabolic and catabolic purposes of central metabolism, but also as a potential source of peroxide required by extracellular peroxidases. There has been some confusion in the literature as to whether this peroxide-generating activity is of the glucose 1-oxidase or pyranose 2-oxidase...

Oxalic acid overproduction by copper-tolerant brown-rot basidiomycetes on southern yellow pine treated with copper-based preservatives

Treesearch

Carol A. Clausen; Frederick Green

2003-01-01

Accumulation of oxalic acid (OA) by brown-rot fungi and precipitation of copper oxalate crystals in wood decayed by copper-tolerant decay fungi has implicated OA in the mechanism of copper tolerance. Understanding the role of OA in copper tolerance is important due to an increasing reliance on copper-based wood preservatives. In this study, four copper-tolerant brown-...

Wood-inhabiting fungi in southern Italy forest stands: morphogroups, vegetation types and decay classes.

PubMed

Granito, Vito Mario; Lunghini, Dario; Maggi, Oriana; Persiani, Anna Maria

2015-01-01

The authors conducted an ecological study of forests subjected to varying management. The aim of the study was to extend and integrate, within a multivariate context, knowledge of how saproxylic fungal communities behave along altitudinal/vegetational gradients in response to the varying features and quality of coarse woody debris (CWD). The intra-annual seasonal monitoring of saproxylic fungi, based on sporocarp inventories, was used to investigate saproxylic fungi in relation to vegetation types and management categories. We analyzed fungal species occurrence, recorded according to the presence/absence and frequency of sporocarps, on the basis of the harvest season, of coarse woody debris decay classes as well as other environmental and ecological variables. Two-way cluster analysis, DCA and Spearman's rank correlations, for indirect gradient analysis, were performed to identify any patterns of seasonality and decay. Most of the species were found on CWD in an intermediate decay stage. The first DCA axis revealed the vegetational/microclimate gradient as the main driver of fungal community composition, while the second axis corresponded to a strong gradient of CWD decay classes. © 2015 by The Mycological Society of America.

Long-term behaviour of timber structures in torrent control

NASA Astrophysics Data System (ADS)

Rickli, Christian; Graf, Frank

2014-05-01

Timber is widely used for protection measures in torrent control. However, life span of woody constructions such as timber check dams is limited due to fungal decay. However, only sparse scientific information is available on the long-term behaviour of timber structures and the colonisation with decay fungi. Related to this, in practice a controversial discussion has been going on if either Norway Spruce (Picea abies) or Silver Fir (Abies alba) is more enduring and if bark removal increases resistance against fungal decay. In order to going into this matter a series of 15 timber check dams built in 1996 has been monitored. The constructions were alternatively realised with Norway Spruce and Silver Fir, half of them each with remaining and removed bark, respectively. The scientific investigations included the documentation of colonisation with rot fungi and the identification of decayed zones with a simple practical approach as well as based on drilling resistance. Colonisation by decay fungi started three years after construction (e.g. Gloeophyllum sepiarium), detecting two years later first parts with reduced wood resistance. Sixteen years after construction decay was found on all check dams but two. Wood quality was markedly better in watered sections compared to the occasionally dry lateral abutment sections. Taking the whole check dams into consideration, slightly more decay was detected in Norway Spruce compared to logs in Silver Fir and both the practical approach and the drilling resistance measurement yielded in more defects on logs without bark. However, due to limited number of replications and fungal data, it was not possible to statistically verify these results. Statistical analysis was restricted to the drilling resistance data and fruit-bodies of decay fungi of the uppermost log of each check dam. Based on this limited analysis significant differences in the effect on the drilling resistance were found for watered sections and lateral abutments, brown and white rot as well as fir with and without bark. Taking further into account that brown rot reduces wood strength faster than white rot, it may be speculated that spruce logs without bark and fir logs with bark are more resistant against fungal decay compared to logs of spruce with and fir without bark, respectively. However, this has to be treated with caution as only the uppermost logs were considered, the observation period was only 15 years and the relative abundance of the most important decay fungi considerably varied between as well as within the check dams. Consequently, for statistically sound and well-funded recommendations further investigations over a longer period are indispensable.

Heart rot hotel: fungal communities in red-cockaded woodpecker excavations

Treesearch

Michelle A. Jusino; Daniel L. Lindner; Mark T. Banik; Jeffrey R. Walters

2015-01-01

Tree-cavity excavators such as woodpeckers are ecosystem engineers that have potentially complex but poorly documented associations with wood decay fungi. Fungi facilitate cavity excavation by preparing and modifying excavation sites for cavity excavators. Associations between fungi and endangered red-cockaded woodpeckers (RCWs) are particularly interesting because...

Bioremediation of treated wood with fungi

Treesearch

Barbara L. Illman; Vina W. Yang

2006-01-01

The authors have developed technologies for fungal bioremediation of waste wood treated with oilborne or metal-based preservatives. The technologies are based on specially formulated inoculum of wood-decay fungi, obtained through strain selection to obtain preservative-tolerant fungi. This waste management approach provides a product with reduced wood volume and the...

A Minimally Invasive Method for Sampling Nest and Roost Cavities for Fungi: a Novel Approach to Identify the Fungi Associated with Cavity-Nesting Birds

Treesearch

Michelle A. Jusino; Daniel Lindner; John K. Cianchetti; Adam T. Grisé; Nicholas J. Brazee; Jeffrey R. Walters

2014-01-01

Relationships among cavity-nesting birds, trees, and wood decay fungi pose interesting management challenges and research questions in many systems. Ornithologists need to understand the relationships between cavity-nesting birds and fungi in order to understand the habitat requirements of these birds. Typically, researchers rely on fruiting body surveys to identify...

Directional change in tunneling of subterranean termites (Isoptera: Rhinotermitidae) in response to decayed wood attractants.

PubMed

Su, Nan-Yao

2005-04-01

Wood discs decayed with brown rot fungi and polymer discs impregnated with acetone extract of decayed wood were embedded in sand of a two-dimensional foraging arena to evaluate their attractant potential in directing termite tunnels toward them. Termites were released near one arena corner and were guided to follow the physical guideline of the arena edges. In the absence of the attractants, termites generally formed a relatively linear tunnel along the edges. When decayed wood discs or treated polymer discs were placed in wet sand near one side of the arena, termite tunnels departed from the arena edges and were oriented toward them. The attraction distance ranged from 12 to 18 cm. The attractant properties were most likely water soluble and permeated through wet sand to cause termites to change their orientation. The results demonstrated that when such attractants are placed near a bait station in the field, they may be used to direct termite foraging toward the station.

Extensive sampling of basidiomycete genomes demonstrates inadequacy of the white rot/ brown rot paradigm for wood decay fungi

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riley, Robert; Salamov, Asaf; Brown, Daren W.

Basidiomycota (basidiomycetes) make up 32percent of the described fungi and include most wood decaying species, as well as pathogens and mutualistic symbionts. Wood-decaying basidiomycetes have typically been classified as either white rot or brown rot, based on the ability (in white rot only) to degrade lignin along with cellulose and hemicellulose. Prior genomic comparisons suggested that the two decay modes can be distinguished based on the presence or absence of ligninolytic class II peroxidases (PODs), as well as the abundance of enzymes acting directly on crystalline cellulose (reduced in brown rot). To assess the generality of the white rot/brown rotmore » classification paradigm we compared the genomes of 33 basidiomycetes, including four newly sequenced wood decayers, and performed phylogenetically-informed Principal Components Analysis (PCA) of a broad range of gene families encoding plant biomass-degrading enzymes. The newly sequenced Botryobasidium botryosum and Jaapia argillacea genomes lack PODs, but possess diverse enzymes acting on crystalline cellulose, and they group close to the model white rot species Phanerochaete chrysosporium in the PCA. Furthermore, laboratory assays showed that both B. botryosum and J. argillacea can degrade all polymeric components of woody plant cell walls, a characteristic of white rot. We also found expansions in reducing polyketide synthase genes specific to the brown rot fungi. Our results suggest a continuum rather than a dichotomy between the white rot and brown rot modes of wood decay. A more nuanced categorization of rot types is needed, based on an improved understanding of the genomics and biochemistry of wood decay.« less

Extensive sampling of basidiomycete genomes demonstrates inadequacy of the white-rot/brown-rot paradigm for wood decay fungi

PubMed Central

Riley, Robert; Salamov, Asaf A.; Brown, Daren W.; Nagy, Laszlo G.; Floudas, Dimitrios; Held, Benjamin W.; Levasseur, Anthony; Lombard, Vincent; Morin, Emmanuelle; Otillar, Robert; Lindquist, Erika A.; Sun, Hui; LaButti, Kurt M.; Schmutz, Jeremy; Jabbour, Dina; Luo, Hong; Baker, Scott E.; Pisabarro, Antonio G.; Walton, Jonathan D.; Blanchette, Robert A.; Henrissat, Bernard; Martin, Francis; Cullen, Dan; Hibbett, David S.; Grigoriev, Igor V.

2014-01-01

Basidiomycota (basidiomycetes) make up 32% of the described fungi and include most wood-decaying species, as well as pathogens and mutualistic symbionts. Wood-decaying basidiomycetes have typically been classified as either white rot or brown rot, based on the ability (in white rot only) to degrade lignin along with cellulose and hemicellulose. Prior genomic comparisons suggested that the two decay modes can be distinguished based on the presence or absence of ligninolytic class II peroxidases (PODs), as well as the abundance of enzymes acting directly on crystalline cellulose (reduced in brown rot). To assess the generality of the white-rot/brown-rot classification paradigm, we compared the genomes of 33 basidiomycetes, including four newly sequenced wood decayers, and performed phylogenetically informed principal-components analysis (PCA) of a broad range of gene families encoding plant biomass-degrading enzymes. The newly sequenced Botryobasidium botryosum and Jaapia argillacea genomes lack PODs but possess diverse enzymes acting on crystalline cellulose, and they group close to the model white-rot species Phanerochaete chrysosporium in the PCA. Furthermore, laboratory assays showed that both B. botryosum and J. argillacea can degrade all polymeric components of woody plant cell walls, a characteristic of white rot. We also found expansions in reducing polyketide synthase genes specific to the brown-rot fungi. Our results suggest a continuum rather than a dichotomy between the white-rot and brown-rot modes of wood decay. A more nuanced categorization of rot types is needed, based on an improved understanding of the genomics and biochemistry of wood decay. PMID:24958869

Comparative Analysis of 35 Basidiomycete Genomes Reveals Diversity and Uniqueness of the Phylum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riley, Robert; Salamov, Asaf; Otillar, Robert

Fungi of the phylum Basidiomycota (basidiomycetes), make up some 37percent of the described fungi, and are important in forestry, agriculture, medicine, and bioenergy. This diverse phylum includes symbionts, pathogens, and saprobes including wood decaying fungi. To better understand the diversity of this phylum we compared the genomes of 35 basidiomycete fungi including 6 newly sequenced genomes. The genomes of basidiomycetes span extremes of genome size, gene number, and repeat content. A phylogenetic tree of Basidiomycota was generated using the Phyldog software, which uses all available protein sequence data to simultaneously infer gene and species trees. Analysis of core genes revealsmore » that some 48percent of basidiomycete proteins are unique to the phylum with nearly half of those (22percent) comprising proteins found in only one organism. Phylogenetic patterns of plant biomass-degrading genes suggest a continuum rather than a sharp dichotomy between the white rot and brown rot modes of wood decay among the members of Agaricomycotina subphylum. There is a correlation of the profile of certain gene families to nutritional mode in Agaricomycotina. Based on phylogenetically-informed PCA analysis of such profiles, we predict that that Botryobasidium botryosum and Jaapia argillacea have properties similar to white rot species, although neither has liginolytic class II fungal peroxidases. Furthermore, we find that both fungi exhibit wood decay with white rot-like characteristics in growth assays. Analysis of the rate of discovery of proteins with no or few homologs suggests the high value of continued sequencing of basidiomycete fungi.« less

Grapevine Botryosphaeria dieback fungi have specific aggressiveness factor repertory involved in wood decay and stilbene metabolization.

PubMed

Stempien, Elodie; Goddard, Mary-Lorène; Wilhelm, Kim; Tarnus, Céline; Bertsch, Christophe; Chong, Julie

2017-01-01

Grapevine trunk diseases: Eutypa dieback, esca and Botryosphaeria dieback, which incidence has increased recently, are associated with several symptoms finally leading to the plant death. In the absence of efficient treatments, these diseases are a major problem for the viticulture; however, the factors involved in disease progression are not still fully identified. In order to get a better understanding of Botryosphaeria dieback development in grapevine, we have investigated different factors involved in Botryosphaeriaceae fungi aggressiveness. We first evaluated the activity of the wood-degrading enzymes of different isolates of Neofusicoccum parvum and Diplodia seriata, two major fungi associated with Botryosphaeria dieback. We further examinated the ability of these fungi to metabolize major grapevine phytoalexins: resveratrol and δ-viniferin. Our results demonstrate that Botryosphaeriaceae were characterized by differential wood decay enzymatic activities and have the capacity to rapidly degrade stilbenes. N. parvum is able to degrade parietal polysaccharides, whereas D. seriata has a better capacity to degrade lignin. Growth of both fungi exhibited a low sensitivity to resveratrol, whereas δ-viniferin has a fungistatic effect, especially on N. parvum Bourgogne S-116. We further show that Botryosphaeriaceae are able to metabolize rapidly resveratrol and δ-viniferin. The best stilbene metabolizing activity was measured for D. seriata. In conclusion, the different Botryosphaeriaceae isolates are characterized by a specific aggressiveness repertory. Wood and phenolic compound decay enzymatic activities could enable Botryosphaeriaceae to bypass chemical and physical barriers of the grapevine plant. The specific signature of Botryosphaeriaceae aggressiveness factors could explain the importance of fungi complexes in synergistic activity in order to fully colonize the host.

Network Analysis Reveals Ecological Links between N-Fixing Bacteria and Wood-Decaying Fungi

PubMed Central

Hoppe, Björn; Kahl, Tiemo; Karasch, Peter; Wubet, Tesfaye; Bauhus, Jürgen; Buscot, François; Krüger, Dirk

2014-01-01

Nitrogen availability in dead wood is highly restricted and associations with N-fixing bacteria are thought to enable wood-decaying fungi to meet their nitrogen requirements for vegetative and generative growth. We assessed the diversity of nifH (dinitrogenase reductase) genes in dead wood of the common temperate tree species Fagus sylvatica and Picea abies from differently managed forest plots in Germany using molecular tools. By incorporating these genes into a large compilation of published nifH sequences and subsequent phylogenetic analyses of deduced proteins we verified the presence of diverse pools corresponding to functional nifH, almost all of which are new to science. The distribution of nifH genes strongly correlated with tree species and decay class, but not with forest management, while higher fungal fructification was correlated with decreasing nitrogen content of the dead wood and positively correlated with nifH diversity, especially during the intermediate stage of wood decay. Network analyses based on non-random species co-occurrence patterns revealed interactions among fungi and N-fixing bacteria in the dead wood and strongly indicate the occurrence of at least commensal relationships between these taxa. PMID:24505405

Network analysis reveals ecological links between N-fixing bacteria and wood-decaying fungi.

PubMed

Hoppe, Björn; Kahl, Tiemo; Karasch, Peter; Wubet, Tesfaye; Bauhus, Jürgen; Buscot, François; Krüger, Dirk

2014-01-01

Nitrogen availability in dead wood is highly restricted and associations with N-fixing bacteria are thought to enable wood-decaying fungi to meet their nitrogen requirements for vegetative and generative growth. We assessed the diversity of nifH (dinitrogenase reductase) genes in dead wood of the common temperate tree species Fagus sylvatica and Picea abies from differently managed forest plots in Germany using molecular tools. By incorporating these genes into a large compilation of published nifH sequences and subsequent phylogenetic analyses of deduced proteins we verified the presence of diverse pools corresponding to functional nifH, almost all of which are new to science. The distribution of nifH genes strongly correlated with tree species and decay class, but not with forest management, while higher fungal fructification was correlated with decreasing nitrogen content of the dead wood and positively correlated with nifH diversity, especially during the intermediate stage of wood decay. Network analyses based on non-random species co-occurrence patterns revealed interactions among fungi and N-fixing bacteria in the dead wood and strongly indicate the occurrence of at least commensal relationships between these taxa.

Response of maple sapwood to injury and infection

Treesearch

W.C. Shortle; K.T. Smith; K.R. Dudzik; Sharon Parker

1995-01-01

In sapwood challenge experiments in Acer rubrum, columns of discolouration initiated by wounding and inoculation with pioneer fungi (Cephalosporium sp., Phialophora sp.) were similar in size to untreated wounds. Inoculation with decay fungi (Pleurotus ostreatus, Trametes versicolor) produced...

Exploring the hypothesis that limiting diffusion of fungal oxidants underlies decay resistance in acetylated wood

Treesearch

Christopher G. Hunt; Steven Lacher; Kolby Hirth; Linda Lorenz; Kenneth E. Hammel

2017-01-01

The mechanisms by which chemical modifications, specifically acetylation, improve the decay resistance of wood are a topic of active research. In the early stages of decay, fungi secrete lowmolecular- weight oxidants or oxidant precursors. These oxidants diffuse through the wet wood cell wall and oxidize cell wall polymers, which enable the decay process to proceed....

Sarcoporia polyspora (Basidiomycota, Polyporales): a rare wood-decay fungus newly recorded from South America

Treesearch

Daiana Bortoluzzi Baldoni; Beatriz Ortiz-Santana; Gilberto Coelho; Zaida I. Antoniolli; Rodrigo J.S. Jacques

2014-01-01

Brown-rot fungi degrade almost exclusively wood cellulosic materials participating in the, carbon cycle and soil formation of many forest regions, these are especially important on boreal and cultivated coniferous forests. These fungi and forests may have a common co-evolutionary history. Studying wood-inhabiting fungi in cultivated pine forests in Southern Brazil, we...

Effect of lauricidin and ethylenediaminetetraacetic acid on growth of nine hymenomycetous fungi.

Treesearch

C. Y. Li; Paul E. Aho

1984-01-01

Growth of nine wood-decaying basidiomycetes was measured on media containing 10, 100, and 1,000 parts per million (p/m) Lauricidin with or without 0.1 percent ethylenediaminetetraacetic acid (EDTA). EDTA alone significantly reduced the growth of all fungi tested. Lauricidin at 1,000 p/m significantly retarded the growth of all fungi except two: Ganoderma...

Examination of fungi in domestic interiors by using factor analysis: Correlations and associations with home factors. [Cladosporium, Alternaria, Epicoccum, Aureobasidium, Aspergillus; Penicillium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Su, H.J.; Rotnitzky, A.; Spengler, J.D.

1992-01-01

Factor analysis was utilized to investigate correlations among airborne microorganisms collected with Andersen samplers from homes in Topeka, Kans., during the winter of 1987 to 1988. The factors derived were used to relate microbial concentrations with categorical, questionnaire-derived descriptions of housing conditions. This approach successfully identified groups of common aboveground decay fungi including Cladosporium, Alternaria, Epicoccum, and Aureobasidium spp. The common soil fungi Aspergillus and Penicillium spp. were also separated as a group. These previously known ecological groupings were confirmed with air sampling data by a quantitative evaluation technique. The above ground decay fungi sampled indoors in winter were presentmore » at relatively high concentrations in homes with gas stoves for cooking, suggesting a possible association between these fungi and increased humidity from the combustion process. Elevated concentrations of the soil fungi were significantly associated with the dirt floor, crawl-space type of basement. Elevated concentrations of water-requiring fungi, such as Fusarium spp., were shown to be associated with water collection in domestic interiors. Also, elevated mean concentrations for the group of fungi including Cladosporium, Epicoccum, Aureobasidium, and yeast spp. were found to be associated with symptoms reported on a health questionnaire. This finding was consistent with the authors previous study of associations between respiratory health and airborne microorganisms by univariate logistic regression analysis.« less

Comparative analysis of secretomes from Ectomycorrhizal fungi with an emphasis on small-secreted proteins

DOE PAGES

Pellegrin, Clement; Morin, Emmanuelle; Martin, Francis M.; ...

2015-11-18

Fungi are major players in the carbon cycle in forest ecosystems due to the wide range of interactions they have with plants either through soil degradation processes by litter decayers or biotrophic interactions with pathogenic and ectomycorrhizal symbionts. Secretion of fungal proteins mediates these interactions by allowing the fungus to interact with its environment and/or host. Ectomycorrhizal (ECM) symbiosis independently appeared several times throughout evolution and involves approximately 80% of trees. Despite extensive physiological studies on ECM symbionts, little is known about the composition and specificities of their secretomes. In this study, we used a bioinformatics pipeline to predict andmore » analyze the secretomes of 49 fungal species, including 11 ECM fungi, wood and soil decayers and pathogenic fungi to tackle the following questions: (1) Are there differences between the secretomes of saprophytic and ECM fungi? (2) Are small-secreted proteins (SSPs) more abundant in biotrophic fungi than in saprophytic fungi? and (3) Are there SSPs shared between ECM, saprotrophic and pathogenic fungi? We showed that the number of predicted secreted proteins is similar in the surveyed species, independently of their lifestyle. The secretome from ECM fungi is characterized by a restricted number of secreted CAZymes, but their repertoires of secreted proteases and lipases are similar to those of saprotrophic fungi. Focusing on SSPs, we showed that the secretome of ECM fungi is enriched in SSPs compared with other species. Most of the SSPs are coded by orphan genes with no known PFAM domain or similarities to known sequences in databases. Finally, based on the clustering analysis, we identified shared- and lifestyle-specific SSPs between saprotrophic and ECM fungi. The presence of SSPs is not limited to fungi interacting with living plants as the genome of saprotrophic fungi also code for numerous SSPs. As a result, ECM fungi shared lifestyle-specific SSPs likely involved in symbiosis that are good candidates for further functional analyses.« less

Comparative analysis of secretomes from Ectomycorrhizal fungi with an emphasis on small-secreted proteins

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pellegrin, Clement; Morin, Emmanuelle; Martin, Francis M.

Fungi are major players in the carbon cycle in forest ecosystems due to the wide range of interactions they have with plants either through soil degradation processes by litter decayers or biotrophic interactions with pathogenic and ectomycorrhizal symbionts. Secretion of fungal proteins mediates these interactions by allowing the fungus to interact with its environment and/or host. Ectomycorrhizal (ECM) symbiosis independently appeared several times throughout evolution and involves approximately 80% of trees. Despite extensive physiological studies on ECM symbionts, little is known about the composition and specificities of their secretomes. In this study, we used a bioinformatics pipeline to predict andmore » analyze the secretomes of 49 fungal species, including 11 ECM fungi, wood and soil decayers and pathogenic fungi to tackle the following questions: (1) Are there differences between the secretomes of saprophytic and ECM fungi? (2) Are small-secreted proteins (SSPs) more abundant in biotrophic fungi than in saprophytic fungi? and (3) Are there SSPs shared between ECM, saprotrophic and pathogenic fungi? We showed that the number of predicted secreted proteins is similar in the surveyed species, independently of their lifestyle. The secretome from ECM fungi is characterized by a restricted number of secreted CAZymes, but their repertoires of secreted proteases and lipases are similar to those of saprotrophic fungi. Focusing on SSPs, we showed that the secretome of ECM fungi is enriched in SSPs compared with other species. Most of the SSPs are coded by orphan genes with no known PFAM domain or similarities to known sequences in databases. Finally, based on the clustering analysis, we identified shared- and lifestyle-specific SSPs between saprotrophic and ECM fungi. The presence of SSPs is not limited to fungi interacting with living plants as the genome of saprotrophic fungi also code for numerous SSPs. As a result, ECM fungi shared lifestyle-specific SSPs likely involved in symbiosis that are good candidates for further functional analyses.« less

Comparative Analysis of Secretomes from Ectomycorrhizal Fungi with an Emphasis on Small-Secreted Proteins

PubMed Central

Pellegrin, Clement; Morin, Emmanuelle; Martin, Francis M.; Veneault-Fourrey, Claire

2015-01-01

Fungi are major players in the carbon cycle in forest ecosystems due to the wide range of interactions they have with plants either through soil degradation processes by litter decayers or biotrophic interactions with pathogenic and ectomycorrhizal symbionts. Secretion of fungal proteins mediates these interactions by allowing the fungus to interact with its environment and/or host. Ectomycorrhizal (ECM) symbiosis independently appeared several times throughout evolution and involves approximately 80% of trees. Despite extensive physiological studies on ECM symbionts, little is known about the composition and specificities of their secretomes. In this study, we used a bioinformatics pipeline to predict and analyze the secretomes of 49 fungal species, including 11 ECM fungi, wood and soil decayers and pathogenic fungi to tackle the following questions: (1) Are there differences between the secretomes of saprophytic and ECM fungi? (2) Are small-secreted proteins (SSPs) more abundant in biotrophic fungi than in saprophytic fungi? and (3) Are there SSPs shared between ECM, saprotrophic and pathogenic fungi? We showed that the number of predicted secreted proteins is similar in the surveyed species, independently of their lifestyle. The secretome from ECM fungi is characterized by a restricted number of secreted CAZymes, but their repertoires of secreted proteases and lipases are similar to those of saprotrophic fungi. Focusing on SSPs, we showed that the secretome of ECM fungi is enriched in SSPs compared with other species. Most of the SSPs are coded by orphan genes with no known PFAM domain or similarities to known sequences in databases. Finally, based on the clustering analysis, we identified shared- and lifestyle-specific SSPs between saprotrophic and ECM fungi. The presence of SSPs is not limited to fungi interacting with living plants as the genome of saprotrophic fungi also code for numerous SSPs. ECM fungi shared lifestyle-specific SSPs likely involved in symbiosis that are good candidates for further functional analyses. PMID:26635749

Decay not serious in northern red oak

Treesearch

Frederick H. Berry; John A. Beaton

1971-01-01

A study of 114 northern red oak, Quercus rubra, indicated that decay is not serious during the time necessary to produce high-quality saw logs and veneer logs. Two heart-rot fungi, Poria oleraceae and P. cocos, accounted for almost 25 percent of the total decay volume in the study trees. Basal fire wounds, dead...

Wood decay fungi of subalpine conifer forests

Treesearch

Jessie A. Glaeser; Kevin T. Smith

2016-01-01

One of the fundamental skills needed for hazard tree assessment is the evaluation of decay. This may be a difficult task as we usually only use external symptoms (wounds, basal swellings, decayed branch stubs), signs (mushrooms, fungal crusts or brackets) or mechanical/indirect sampling methods (drilling, electrical or sonic resistance) to estimate the amount of sound...

Ecosystem processes related to wood decay

Treesearch

Bruce G. Marcot

2017-01-01

Wood decay elements include snags, down wood, root wads, tree stumps, litter, duff, broomed or diseased branches, and partially dead trees, all of which contribute to ecological processes and biodiversity of the forest ecosystem. Down wood can serve as reservoirs for moisture and mycorrhizal fungi beneficial to the health and growth of commercial tree species. Decaying...

Changes in structural and chemical components of wood delignified by fungi

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blanchette, R.A.; Otjen, L.; Effland, M.J.

1985-01-01

Cerrena unicolor, Ganoderma applanatum, Ischnoderma resinosum and Poria medulla-panis were associated with birch (Betula papyrifera) wood that had been selectively delignified in the forest. Preferential lignin degradation was not uniformly distributed throughout the decayed wood. A typical white rot causing a simultaneous removal of all cell wall components was also present. In the delignified wood, 95 to 98% of the lignin was removed as well as substantial amounts of hemicelluloses. Scanning and transmission electron microscopy were used to identify the micromorphological and ultrastructural changes that occurred in the cells during degradation. In delignified areas the compound middle lamella was extensivelymore » degraded causing a defibration of cells. The secondary wall, especially the S2 layer, remained relatively unaltered. In simultaneously white-rotted wood all cell wall layers were progressively removed from the lumen toward the middle lamella causing erosion troughs or holes to form. Large voids filled with fungal mycelia resulted from a coalition of degraded areas. Birch wood decayed in laboratory soil-block tests was also intermittently delignified, selective delignification, sparsely distributed throughout the wood, and a simultaneous rot resulting in the removal of all cell wall components were evident. SEM appears to be an appropriate technique for examining selectively delignified decayed wood. 30 references.« less

Grapevine Botryosphaeria dieback fungi have specific aggressiveness factor repertory involved in wood decay and stilbene metabolization

PubMed Central

Wilhelm, Kim; Tarnus, Céline; Bertsch, Christophe

2017-01-01

Grapevine trunk diseases: Eutypa dieback, esca and Botryosphaeria dieback, which incidence has increased recently, are associated with several symptoms finally leading to the plant death. In the absence of efficient treatments, these diseases are a major problem for the viticulture; however, the factors involved in disease progression are not still fully identified. In order to get a better understanding of Botryosphaeria dieback development in grapevine, we have investigated different factors involved in Botryosphaeriaceae fungi aggressiveness. We first evaluated the activity of the wood-degrading enzymes of different isolates of Neofusicoccum parvum and Diplodia seriata, two major fungi associated with Botryosphaeria dieback. We further examinated the ability of these fungi to metabolize major grapevine phytoalexins: resveratrol and δ-viniferin. Our results demonstrate that Botryosphaeriaceae were characterized by differential wood decay enzymatic activities and have the capacity to rapidly degrade stilbenes. N. parvum is able to degrade parietal polysaccharides, whereas D. seriata has a better capacity to degrade lignin. Growth of both fungi exhibited a low sensitivity to resveratrol, whereas δ-viniferin has a fungistatic effect, especially on N. parvum Bourgogne S-116. We further show that Botryosphaeriaceae are able to metabolize rapidly resveratrol and δ-viniferin. The best stilbene metabolizing activity was measured for D. seriata. In conclusion, the different Botryosphaeriaceae isolates are characterized by a specific aggressiveness repertory. Wood and phenolic compound decay enzymatic activities could enable Botryosphaeriaceae to bypass chemical and physical barriers of the grapevine plant. The specific signature of Botryosphaeriaceae aggressiveness factors could explain the importance of fungi complexes in synergistic activity in order to fully colonize the host. PMID:29261692

Antifungal activities of three supercritical fluid extracted cedar oils

Treesearch

Tianchuan Du; Todd F. Shupe; Chung Y. Hse

2009-01-01

The antifungal activities of three supercritical CO2 (SCC) extracted cedar oils, Port-Orford-cedar (POC) (Chamaecyparis lawsoniana), Alaska yellow cedar (AYC) (Chamaecyparis nootkatensis), and Eastern red cedar (ERC) (Juniperus virginiana L), were evaluated against two common wood decay fungi, brown-rot fungi (...

Production and degradation of oxalic acid by brown rot fungi

DOE Office of Scientific and Technical Information (OSTI.GOV)

Espejo, E.; Agosin, E.

1991-07-01

Our results show that all of the brown rot fungi tested produce oxalic acid in liquid as well as in semisolid cultures. Gloeophyllum trabeum, which accumulates the lowest amount of oxalic acid during decay of pine holocellulose, showed the highest polysaccharide-depolymerizing activity. Semisolid cultures inoculated with this fungus rapidly converted {sup 14}C-labeled oxalic acid to CO{sub 2} during cellulose depolymerization. The other brown rot fungi also oxidized {sup 14}C-labeled oxalic acid, although less rapidly. In contrast, semisolid cultures inoculated with the white rot fungus Coriolus versicolor did not significantly catabolize the acid and did not depolymerize the holocellulose during decay.more » Semisolid cultures of G. trabeum amended with desferrioxamine, a specific iron-chelating agent, were unable to lower the degree of polymerization of cellulose or to oxidize {sup 14}C-labeled oxalic acid to the extent or at the rate that control cultures did. These results suggest that both iron and oxalic acid are involved in cellulose depolymerization by brown rot fungi.« less

Fungal degradation of wood lignins: Geochemical perspectives from CuO-derived phenolic dimers and monomers

NASA Astrophysics Data System (ADS)

Goñi, Miguel A.; Nelson, Bryan; Blanchette, Robert A.; Hedges, John I.

1993-08-01

The elemental compositions and yields of CuO-derived phenol dimers and monomers from woods degraded by different fungi under laboratory and natural conditions were compared to those from undegraded controls. In laboratory experiments, white-rot fungi caused pronounced mass losses, lowered the organic carbon content of the remnant woods, and decreased the absolute carbon-normalized yields of the major classes of lignin phenol dimers and monomers. White-rot decay induced large losses of some CuO reaction products, such as (β,1-diketone and α,l-monoketone dimers and syringyl monomers, and increased the absolute yields of individual acidic reaction products, such as dehydrodivanillic acid, vanillic acid, and 2-syringylsyringic acid. In contrast, the brown-rot fungus, Fomitopsis pinicola, was less efficient in decaying lignin, inducing lower absolute lignin phenol losses and, in some cases, increasing the organic carbon content of remnant woods. Several lignin constituents, mainly carboxyvanillyl monomers and α,2-methyl and α,5-monoketone dimers, were produced during brown-rot degradation. Similar diagenetic trends were also apparent in the five woods collected from the field, suggesting the differences between white- and brown-rot decay are still apparent after more extensive degradation in natural environments. The lignin compositions from a selected set of previously analyzed sedimentary mixtures were generally consistent with the diagenetic trends observed in both laboratory and field samples. In some cases, however, geochemical parameters such as elevated dimer/monomer and carboxyvanillyl/ vanillyl monomer ratios clearly distinguished certain sedimentary lignins. In these samples, other processes, such as extensive fungal decay, bacterial degradation, or a nonwoody vascular plant origin, could be important factors affecting lignin compositions.

Bacterial associations with decaying wood : a review

Treesearch

C. A. Clausen

1996-01-01

Wood-inhabiting bacteria are associated with wood decay and may have an indirect influence on the decay process. Bacteria are able to affect wood permeability, attack wood structure, or work synergistically with other bacteria and soft-rot fungi to predispose wood to fungal attack. Bacteria that can inhabit chemically treated wood are recognized. The natural ability of...

The fungus that came in from the cold: dry rot's pre-adapted ability to invade buildings.

PubMed

Balasundaram, S V; Hess, J; Durling, M B; Moody, S C; Thorbek, L; Progida, C; LaButti, K; Aerts, A; Barry, K; Grigoriev, I V; Boddy, L; Högberg, N; Kauserud, H; Eastwood, D C; Skrede, I

2018-03-01

Many organisms benefit from being pre-adapted to niches shaped by human activity, and have successfully invaded man-made habitats. One such species is the dry rot fungus Serpula lacrymans, which has a wide distribution in buildings in temperate and boreal regions, where it decomposes coniferous construction wood. Comparative genomic analyses and growth experiments using this species and its wild relatives revealed that S. lacrymans evolved a very effective brown rot decay compared to its wild relatives, enabling an extremely rapid decay in buildings under suitable conditions. Adaptations in intracellular transport machineries promoting hyphal growth, and nutrient and water transport may explain why it is has become a successful invader of timber in houses. Further, we demonstrate that S. lacrymans has poor combative ability in our experimental setup, compared to other brown rot fungi. In sheltered indoor conditions, the dry rot fungus may have limited encounters with other wood decay fungi compared to its wild relatives. Overall, our analyses indicate that the dry rot fungus is an ecological specialist with poor combative ability against other fungi.

Research on biodeterioration of wood, 1987-1992. 1. Decay mechanisms and biocontrol. Forest Service research paper

DOE Office of Scientific and Technical Information (OSTI.GOV)

Highley, T.L.; Clausen, C.A.; Croan, S.C.

1994-03-01

Growing concerns about the environment present an urgent need for new approaches to preserving wood. Some commonly used preservatives have been banned or restricted in several countries. The research paper first describes current knowledge about how white-and-brown rot fungi decay wood and then delineates research in to problem areas: (1) control of wood decay through targeting biosynthetic and degradative pathways, and (2) biological control (biocontrol) of wood decay through non-decay micro-organisms.

Antifungal activity of peppermint and sweet basil essential oils and their major aroma constituents on some plant pathogenic fungi from the vapor phase.

PubMed

Edris, Amr E; Farrag, Eman S

2003-04-01

The vapors of peppermint oil and two of its major constituents (menthol and menthone), and sweet basil oil and two of its major constituents (linalool and eugenol), were tested against Sclerotinia sclerotiorum (Lib.), Rhizopus stolonifer (Ehrenb. exFr.) Vuill and Mucor sp. (Fisher) in a closed system. These fungi cause deterioration and heavy decay of peach fruit during marketing, shipping and storage. The essential oils, their major individual aroma constituents and blends of the major individual constituents at different ratios inhibited the growth of the fungi in a dose-dependent manner. Menthol was found to be the individual aroma constituent responsible for the antifungal properties of peppermint essential oil, while menthone alone did not show any effect at all doses. In the case of basil oil, linalool alone showed a moderate antifungal activity while eugenol showed no activity at all. Mixing the two components in a ratio similar to their concentrations in the original oil was found to enhance the antifungal properties of basil oil indicating a synergistic effect.

Chlorine Dioxide for Reduction of Postharvest Pathogen Inoculum during Handling of Tree Fruits

PubMed Central

Roberts, Rodney G.; Reymond, Stephen T.

1994-01-01

Alternatives to hypochlorous acid and fungicides are needed for treatment of fruit and fruit-handling facilities. Chlorine dioxide was evaluated and found effective against common postharvest decay fungi and against filamentous fungi occurring on fruit packinghouse surfaces. In vitro tests with conidial or sporangiospore suspensions of Botrytis cinerea, Penicillium expansum, Mucor piriformis, and Cryptosporiopsis perennans demonstrated >99% spore mortality within 1 min when the fungi were exposed to aqueous chlorine dioxide at 3 or 5 μg · ml-1. Longer exposure times were necessary to achieve similar spore mortalities with 1 μg · ml-1. Of the fungi tested, B. cinerea and P. expansum were the least sensitive to ClO2. In comparison with the number recovered from untreated control areas, the number of filamentous fungi recovered was significantly lower in swipe tests from hard surfaces such as belts and pads in a commercial apple and pear packinghouse after treatment of surfaces with a 14.0- to 18.0-μg · ml-1 ClO2 foam formulation. Chlorine dioxide has desirable properties as a sanitizing agent for postharvest decay management when residues of postharvest fungicides are not desired or allowed. PMID:16349354

Fungi and wind strongly influence the temporal availability of logs in an old-growth spruce forest.

PubMed

Edman, Mattias; Jönsson, Mari; Jonsson, Bengt Gunnar

2007-03-01

Coarse woody debris (CWD) is a key habitat for many species in forest ecosystems. To ensure the long-term survival of such species, forest management regimes must include measures that promote dead wood dynamics similar to those of natural forests. Thus, information on CWD dynamics under natural conditions is required, including data pertaining to the underlying agents of disturbance. This study examines modes of mortality, decay rates, and temporal patterns in the availability of Picea abies logs in a Swedish old-growth forest affected by internal, small-scale disturbance. All 684 logs in a 6.6-ha plot were mapped and classified into one of six decay classes. Logs in the early stages of decay were examined for the presence of heart-rot fungi. Six years later all logs were re-inventoried, including newly formed logs. Matrix models based on the transition rates between decay classes showed that it took about 60 years for 90% of the logs to decay beyond class 6 (a deformed trunk with soft wood). Large logs (> 26 cm) decayed 40% more slowly than small logs (< 25 cm). The initial volume of logs was 37.6 m3/ha but increased to 44.8 m3/ha after six years. In addition, there was a large shift in the decay-class distribution. The volume of logs in early and late decay classes increased by 71% and 45%, respectively, while the volume of logs in the intermediate decay classes decreased by 32%. The fluctuations appear to result from pulses in mortality, driven by a combination of strong winds and the heart-rot fungus, Phellinus chrysoloma, which was present in more than 30% of all logs at an early stage of decay. These results show that large temporal fluctuations in dead wood also occur in the absence of large-scale disturbance, and that heart-rot fungi are important factors driving the overall dynamics of dead wood. Since many wood-inhabiting species are naturally rare and have very specific substrate demands, such temporal variability in dead wood availability may have effects on biodiversity and should be taken into account when designing small, protected forest areas.

Effect of Fungal Competition on Decay Rates in Bicultured Soil Bottle Assays

Treesearch

Grant T. Kirker; Amy Blodgett; Patricia K. Lebow; Carol A. Clausen

2016-01-01

For decades, wood scientists and preservative formulators have employed the monocultured soil bottle assay to test efficacy of wood treatment in the laboratory as a rapid predictor of field performance. This study examines the effects of bicultured soil bottle assays on the decay by common wood decay fungi. Mycelial interactions were noted in early stages of...

The usual suspects : fingerprinting microbial communities involved in decay of treated southern yellow pine

Treesearch

Grant T. Kirker; Susan V. Diehl; M. Lynn Prewitt

2010-01-01

Currrent standards for soil-block testing have long been based on the effectiveness of preservative systems against only a small number of wood decay fungi and even fewer bacteria. Culture-independent molecular methods offer simple, reproducible means to obtain a more holistic view of the microbial communities that colonize wood throughout the decay process. By using a...

Laboratory and environmental decay of wood–plastic composite boards: flexural properties

Treesearch

Rebecca Ibach; Marek Gnatowski; Grace Sun; Jessie Glaeser; Mathew Leung; John Haight

2017-01-01

The flexural properties of wood–plastic composite (WPC) deck boards exposed to 9.5 years of environmental decay in Hilo, Hawaii, were compared to samples exposed to moisture and decay fungi for 12 weeks in the laboratory, to establish a correlation between sample flexural properties and calculated void volume. Specimens were tested for flexural strength and modulus,...

Prevention of fungal spoilage in food products using natural compounds: A review.

PubMed

Ribes, Susana; Fuentes, Ana; Talens, Pau; Barat, Jose Manuel

2017-04-10

The kingdom Fungi is the most important group of microorganism contaminating food commodities, and chemical additives are commonly used in the food industry to prevent fungal spoilage. However, the increasing consumer concern about synthetic additives has led to their substitution by natural compounds in foods. The current review provides an overview of using natural agents isolated from different sources (plants, animals, and microorganisms) as promising antifungal compounds, including information about their mechanism of action and their use in foods to preserve and prolong shelf life. Compounds derived from plants, chitosan, lactoferrin, and biocontrol agents (lactic acid bacteria, antagonistic yeast, and their metabolites) are able to control the decay caused by fungi in a wide variety of foods. Several strategies are employed to reduce the drawbacks of some antifungal agents, like their incorporation into oil-in-water emulsions and nanoemulsions, edible films and active packaging, and their combination with other natural preservatives. These strategies facilitate the addition of volatile agents into food products and, improve their antifungal effectiveness. Moreover, biological agents have been investigated as one of the most promising options in the control of postharvest decay. Numerous mechanisms of action have been elucidated and different approaches have been studied to enhance their antifungal effectiveness.

Application of hinokitiol potassium salt for wood preservative.

PubMed

Hu, Junyi; Shen, Yu; Pang, Song; Gao, Yun; Xiao, Guoyong; Li, Shujun; Xu, Yingqian

2013-12-01

The decay of wood and other cellulosic materials by fungi cause significant economic loss. The widely used chromated copper arsenate was prohibited for the environmental impact and safety of arsenic and chromium. It was found that natural product hinokitiol (HK) had fungicidal and insecticidal activities, and its toxicity was bearable for the environment. We described the practical synthesis of HK-K salt. According to the GB/T18261-2000 and LY/T1283-1998, wood preservative performance of HK-K salt was tested. The results showed that the best inhibitory concentration of HK-K salt was 50 mg/L, for which the prevention effectiveness on mold is better, the killed value is between 0 and 1, and the corrosion-resistant for wood-rotting fungi is grade A. Copyright © 2013 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Influence of corn steep liquor and glucose on colonization of control and CCB (Cu/Cr/B)-treated wood by brown rot fungi

DOE Office of Scientific and Technical Information (OSTI.GOV)

Humar, Miha; Amartey, Sam A.; Pohleven, Franc

2006-07-01

There are increasing problems with regard to the disposal of treated wood waste. Due to heavy metals or arsenic in impregnated wood waste, burning and landfill disposal options are not considered to be environmentally friendly solutions for dealing with this problem. Extraction of the heavy metals and recycling of the preservatives from the wood waste is a much more promising and environmentally friendly solution. In order to study the scale up of this process, copper/chromium/boron-treated wood specimens were exposed to copper tolerant (Antrodia vaillantii and Leucogyrophana pinastri) and copper sensitive wood decay fungi (Gloeophyllum trabeum and Poria monticola). Afterwards, themore » ability of fungal hyphae to penetrate and overgrow the wood specimens was investigated. The fungal growths were stimulated by immersing the specimens into aqueous solution of glucose or corn steep liquor prior to exposure to the fungi. The fastest colonization of the impregnated wood was by the copper tolerant A. vaillantii. Addition of glucose onto the surface of the wood specimens increased the fungi colonization of the specimens; however, immersion of the specimens into the solution of corn steep liquor did not have the same positive influence. These results are important in elucidating copper toxicity in wood decay fungi and for using these fungi for bioremediation of treated wood wastes.« less

Comparative study of fungal deterioration in Liquidambar orientalis mill heartwood extractives

Treesearch

Roderquita K Moore; Doreen Mann; Nural Yilgor

2017-01-01

A comparative study was done on Liquidambar Orientalis Mill heartwood extractive samples. These extractives were collected from wood decay specimens. The objective of the study was to determine the chemical composition of the extractives remaining after exposure to brown rot fungi Tyromyces Palustris and white rot fungi Trametes Vericolor...

Home wreckers in search of moisture

Treesearch

Carol A. Clausen; Frederick Green

2002-01-01

Research at the Forest Products Laboratory (FPL) related to durability and disaster mitigation includes damage by decay fungi and termites and contamination by mold fungi. All these household pests are attracted to excess moisture, which can result from inadequate surface drying of condensation, leaks in pipes and foundations, poor ventila-tion, or flooding. Homeowners...

Determining resistance to soft-rot fungi

Treesearch

C. G. Duncan

1965-01-01

A laboratory procedure is outlined that incorporates techniques found to promote soft rot by several fungi. This procedure employs either an agar or a soil substrate. Also presented are the principal findings of experiments underlying the procedure. Results of tests conducted according to the suggested procedure are illustrated. The overall decay resistance of the...

Plant-Polysaccharide-Degrading Enzymes from Basidiomycetes

PubMed Central

Rytioja, Johanna; Hildén, Kristiina; Yuzon, Jennifer; Hatakka, Annele; de Vries, Ronald P.

2014-01-01

SUMMARY Basidiomycete fungi subsist on various types of plant material in diverse environments, from living and dead trees and forest litter to crops and grasses and to decaying plant matter in soils. Due to the variation in their natural carbon sources, basidiomycetes have highly varied plant-polysaccharide-degrading capabilities. This topic is not as well studied for basidiomycetes as for ascomycete fungi, which are the main sources of knowledge on fungal plant polysaccharide degradation. Research on plant-biomass-decaying fungi has focused on isolating enzymes for current and future applications, such as for the production of fuels, the food industry, and waste treatment. More recently, genomic studies of basidiomycete fungi have provided a profound view of the plant-biomass-degrading potential of wood-rotting, litter-decomposing, plant-pathogenic, and ectomycorrhizal (ECM) basidiomycetes. This review summarizes the current knowledge on plant polysaccharide depolymerization by basidiomycete species from diverse habitats. In addition, these data are compared to those for the most broadly studied ascomycete genus, Aspergillus, to provide insight into specific features of basidiomycetes with respect to plant polysaccharide degradation. PMID:25428937

Effect of Preservative Pretreatment on the Biological Durability of Corn Straw Fiber/HDPE Composites.

PubMed

Xuan, Lihui; Hui, Dongxue; Cheng, Wanli; Wong, Andrew H H; Han, Guangping; Tan, Wei Khong; Tawi, Carlson A D

2017-07-12

The effects of alkaline copper quaternary (ACQ) and zinc borate (ZB) on the resistance of corn stalk fiber (CSF)-reinforced high-density polyethylene (HDPE) composites to biodegradation were examined. Both biocides could inhibit termites, mold fungi, and wood-decay fungi, even at high CSF formulations (i.e., 60%). Additionally, ACQ enhanced the resistance of the composite materials to certain biotic stresses better than ZB. The CSF/HDPE composites treated with ACQ at the 3.0% level exhibited a superior performance against termites, white rot fungi, and brown rot fungi. ACQ treatment at the 1% level was optimal for inhibiting soft rot fungi. Furthermore, mold growth was not observed on ACQ-treated CSF/HDPE samples. The untreated CSF/HDPE composites were more susceptible to mold infections and decay than the untreated poplar/HDPE composites, likely because of an incomplete removal of the pith. The chemical features of the corn stalk may also have influenced these differences, but this possibility will need to be explored in future investigations. Furthermore, the CSF component of CSF/HDPE composites is highly susceptible to fungal attacks, with the soft rot fungus inducing the largest mass losses, followed by the white rot fungus, and then the brown rot fungus.

Marine-derived fungi: diversity of enzymes and biotechnological applications

PubMed Central

Bonugli-Santos, Rafaella C.; dos Santos Vasconcelos, Maria R.; Passarini, Michel R. Z.; Vieira, Gabriela A. L.; Lopes, Viviane C. P.; Mainardi, Pedro H.; dos Santos, Juliana A.; de Azevedo Duarte, Lidia; Otero, Igor V. R.; da Silva Yoshida, Aline M.; Feitosa, Valker A.; Pessoa, Adalberto; Sette, Lara D.

2015-01-01

The ocean is considered to be a great reservoir of biodiversity. Microbial communities in marine environments are ecologically relevant as intermediaries of energy, and play an important role in nutrient regeneration cycles as decomposers of dead and decaying organic matter. In this sense, marine-derived fungi can be considered as a source of enzymes of industrial and/or environmental interest. Fungal strains isolated from different substrates, such as invertebrates, decaying wood, seawater, sediments, and mangrove detritus, have been reported to be producers of hydrolytic and/or oxidative enzymes, with alginate lyase, amylase, cellulase, chitinase, glucosidase, inulinase, keratinase, ligninase, lipase, nuclease, phytase, protease, and xylanase being among the enzymes produced by fungi of marine origin. These enzymes present temperature and pH optima ranging from 35 to 70∘C, and 3.0 to 11.0, respectively. High-level production in bioreactors is mainly performed using submerged-state fermentation. Certain marine-derived fungal strains present enzymes with alkaline and cold-activity characteristics, and salinity is considered an important condition in screening and production processes. The adaptability of marine-derived fungi to oceanic conditions can be considered an attractive point in the field of fungal marine biotechnology. In this review, we focus on the advances in discovering enzymes from marine-derived fungi and their biotechnological relevance. PMID:25914680

Effect of Preservative Pretreatment on the Biological Durability of Corn Straw Fiber/HDPE Composites

PubMed Central

Xuan, Lihui; Hui, Dongxue; Cheng, Wanli; Wong, Andrew H. H.; Han, Guangping; Tan, Wei Khong; Tawi, Carlson A. D.

2017-01-01

The effects of alkaline copper quaternary (ACQ) and zinc borate (ZB) on the resistance of corn stalk fiber (CSF)-reinforced high-density polyethylene (HDPE) composites to biodegradation were examined. Both biocides could inhibit termites, mold fungi, and wood-decay fungi, even at high CSF formulations (i.e., 60%). Additionally, ACQ enhanced the resistance of the composite materials to certain biotic stresses better than ZB. The CSF/HDPE composites treated with ACQ at the 3.0% level exhibited a superior performance against termites, white rot fungi, and brown rot fungi. ACQ treatment at the 1% level was optimal for inhibiting soft rot fungi. Furthermore, mold growth was not observed on ACQ-treated CSF/HDPE samples. The untreated CSF/HDPE composites were more susceptible to mold infections and decay than the untreated poplar/HDPE composites, likely because of an incomplete removal of the pith. The chemical features of the corn stalk may also have influenced these differences, but this possibility will need to be explored in future investigations. Furthermore, the CSF component of CSF/HDPE composites is highly susceptible to fungal attacks, with the soft rot fungus inducing the largest mass losses, followed by the white rot fungus, and then the brown rot fungus. PMID:28773150

Hints on storing timber to prevent decay

Treesearch

Forest Products Laboratory

1919-01-01

Many serious losses from decay in wooden structures are due to the fact that the timbers used were infected with wood-destroying fungi while in storage. These losses can be greatly reduced by keeping lumber storage yards in a sanitary condition. Some hints as to how to do this are given below.

Macrofungi on woody substrata

Treesearch

Sabine M. Huhndorf; D. J. Lodge; Chun-Juan Wang; Jogeir N. Stokland

2004-01-01

Wood-inhabiting macrofungi inhabit substrata that differ in size, state of decay, and moisture content. Thus, the ecologies of fungi growing on wood differ. Wood-inhabiting species include fungi that were in or on the wood when a tree or tree part fell to the ground (e.g., pathogens and nonpathogenic endophytes of living tissue, heart rots), as well as the succession...

The copper-transporting ATPase pump and its potential role in copper-tolerance

Treesearch

Katie Ohno; C.A. Clausen; Frederick Green; G. Stanosz

2016-01-01

Copper-tolerant brown-rot decay fungi exploit intricate mechanisms to neutralize the efficacy of copper-containing preservative formulations. The production and accumulation oxalate is the most widely recognized theory regarding the mechanism of copper-tolerance in these fungi. The role of oxalate, however, may be only one part of a series of necessary components...

Hexadecyl ammonium chloride amylose inclusion complex to emulsify cedarwood oil and treat wood against termites and wood-decay fungi

USDA-ARS?s Scientific Manuscript database

Cedarwood oil (CWO) has a wide range of bioactivities, including insect repellency and toxicity as well as conferring resistance against termites and wood-rot fungi. In previous pressure treatment work, ethanol was used as the diluent/carrier for CWO. However, it is preferable to use a water-based ...

Roles of Woody Root-Associated Fungi in Forest Ecosystem Processes: Recent Advances in Fungal Identification

Treesearch

Jill A. Hoff; Ned B. Klopfenstein; Jonalea R. Tonn; Geral I. McDonald; Paul J. Zambino; Jack D. Rogers; Tobin L. Peever; Lori M. Carris

2004-01-01

Interactions between fungi and woody roots may be critical factors that influence diverse forest ecosystems processes, such as wood decay (nutrient recycling); root diseases and their biological control; and endophytic, epiphytic, and mycorrhizal symbioses. However, few studies have characterized the diversity and the spatial and temporal distribution of woody root-...

Limited Effects of Variable-Retention Harvesting on Fungal Communities Decomposing Fine Roots in Coastal Temperate Rainforests.

PubMed

Philpott, Timothy J; Barker, Jason S; Prescott, Cindy E; Grayston, Sue J

2018-02-01

Fine root litter is the principal source of carbon stored in forest soils and a dominant source of carbon for fungal decomposers. Differences in decomposer capacity between fungal species may be important determinants of fine-root decomposition rates. Variable-retention harvesting (VRH) provides refuge for ectomycorrhizal fungi, but its influence on fine-root decomposers is unknown, as are the effects of functional shifts in these fungal communities on carbon cycling. We compared fungal communities decomposing fine roots (in litter bags) under VRH, clear-cut, and uncut stands at two sites (6 and 13 years postharvest) and two decay stages (43 days and 1 year after burial) in Douglas fir forests in coastal British Columbia, Canada. Fungal species and guilds were identified from decomposed fine roots using high-throughput sequencing. Variable retention had short-term effects on β-diversity; harvest treatment modified the fungal community composition at the 6-year-postharvest site, but not at the 13-year-postharvest site. Ericoid and ectomycorrhizal guilds were not more abundant under VRH, but stand age significantly structured species composition. Guild composition varied by decay stage, with ruderal species later replaced by saprotrophs and ectomycorrhizae. Ectomycorrhizal abundance on decomposing fine roots may partially explain why fine roots typically decompose more slowly than surface litter. Our results indicate that stand age structures fine-root decomposers but that decay stage is more important in structuring the fungal community than shifts caused by harvesting. The rapid postharvest recovery of fungal communities decomposing fine roots suggests resiliency within this community, at least in these young regenerating stands in coastal British Columbia. IMPORTANCE Globally, fine roots are a dominant source of carbon in forest soils, yet the fungi that decompose this material and that drive the sequestration or respiration of this carbon remain largely uncharacterized. Fungi vary in their capacity to decompose plant litter, suggesting that fungal community composition is an important determinant of decomposition rates. Variable-retention harvesting is a forestry practice that modifies fungal communities by providing refuge for ectomycorrhizal fungi. We evaluated the effects of variable retention and clear-cut harvesting on fungal communities decomposing fine roots at two sites (6 and 13 years postharvest), at two decay stages (43 days and 1 year), and in uncut stands in temperate rainforests. Harvesting impacts on fungal community composition were detected only after 6 years after harvest. We suggest that fungal community composition may be an important factor that reduces fine-root decomposition rates relative to those of above-ground plant litter, which has important consequences for forest carbon cycling. Copyright © 2018 American Society for Microbiology.

Nondestructive evaluation of oriented strand board exposed to decay fungi.

Treesearch

Barbara L. Illman; Vina W. Yang; Robert J. Ross; William J. Nelson

2002-01-01

Stress wave nondestructive evaluation (NDE) technologies are being used in our laboratory to evaluate the performance properties of engineered wood. These techniques have proven useful in the inspection of timber structures to locate internal voids and decayed or deteriorated areas in large timbers. But no information exists concerning NDE and important properties of...

Copper radical oxidases and related extracellular oxidoreductases of wood-decay Agaricomycetes

Treesearch

Phil Kersten; Dan Cullen

2014-01-01

Extracellular peroxide generation, a key component of oxidative lignocellulose degradation, has been attributed to various enzymes including the copper radical oxidases. Encoded by a family of structurally related sequences, the genes are widely distributed among wood decay fungi including three recently completed polypore genomes. In all cases, core catalytic residues...

Wood decay by brown-rot fungi : changes in pore structure and cell wall volume

Treesearch

Douglas S. Flournoy; T. Kent Kirk; T.L. Highley

1991-01-01

Sweetgum (Liquidambar styraciflua L.) wood blocks were decayed by Postia (= Poria) placenta in soilblock cultures. Decay was terminated at various weight losses, and the pore volumes available to four low molecular weight molecules, (water, 4 Å,; glucose, 8 Å,; maltose, 10 Å; and raffinose, 128,) and three dextrans (Mr 6,000, 38 Å; 11,200, 51 Å; nd 17,500, 61 Å) were...

Species-specific effects of soil fauna on fungal foraging and decomposition.

PubMed

Crowther, Thomas W; Boddy, Lynne; Jones, T Hefin

2011-10-01

Decomposer fungi are primary decomposing agents in terrestrial soils. Their mycelial networks play an important role in nutrient mineralisation and distribution, but are also nutritious resources for various soil invertebrates. Global climate change is predicted to alter the diversity and community composition of these soil fauna. To understand whether changes in invertebrate species diversity are likely to affect fungal-mediated decomposition, this study compared the grazing potentials of different invertebrate taxa and functional groups. Specifically, the grazing impacts of seven invertebrate taxa on the growth and spatial distribution of six basidiomycete fungi growing from beech wood blocks in soil microcosms were explored. Wood decay rates by fungi were also compared. The consequences of grazing were both taxon- and species-specific. Generally, macro-invertebrates caused the greatest damage, while meso- and micro-invertebrates often stimulated mycelial growth. Invertebrate size, preferences and population dynamics are likely to influence grazing potentials. Effects of grazing varied between fungi, with mycelial morphology and biochemistry possibly influencing susceptibility. Heavy grazing indirectly increased fungal-mediated wood decomposition. Changes in invertebrate community composition are predicted to have consequences for fungal growth, activity and community structure in woodland soils. Abiotic climate change factors including CO(2) and temperature affect mycelial productivity directly, but the indirect effects, mediated through changes in the soil invertebrate community, may be equally important in controlling ecosystem functioning.

Wood-inhabiting, polyporoid fungi in aspen-dominated forests managed for biomass in the U.S. Lake States

Treesearch

Nicholas J. Brazee; Daniel L. Lindner; Shawn Fraver; Anthony W. D' Amato; Amy M. Milo

2012-01-01

To better understand the potential long-term effects of biomass harvesting on biodiversity, the polyporoid fungi community was characterized from 120 plots in four aspen-dominated forests in Minnesota. Four deadwood variables (substratum species, substratum type, decay class and diameter class) were recorded for each polyporoid species occurrence. A total of 2358...

Copper tolerance of brown-rot fungi : oxalic acid production in southern pine treated with arsenic-free preservatives

Treesearch

Frederick Green; Carol A. Clausen

2005-01-01

The voluntary withdrawal of chromated copper arsenate (CCA)-treated wood from most residential applications has increased the use of non-arsenical copper-based organic wood preservatives. Because the arsenic component of CCA controlled copper tolerant fungi, scientists have renewed interest in and concern about the decay capacity in the important copper-tolerant group...

Functional Genomics of Lignocellulose Degradation in the Basidiomycete White Rot Schizophyllum commune

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohm, Robin A.; Tegelaar, Martin; Henrissat, Bernard

2013-03-01

White and brown rot fungi are among the most important wood decayers in nature. Although more than 50 genomes of Basidiomycete white and brown rots have been sequenced by the Joint Genome Institute, there is still a lot to learn about how these fungi degrade the tough polymers present in wood. In particular, very little is known about how these fungi regulate the expression of genes involved in lignocellulose degradation. Here, we used transcriptomics, proteomics, and promoter analysis in an effort to gain insight into the process of lignocellulose degradation.

Horizontal gene transfer and gene dosage drives adaptation to wood colonization in a tree pathogen

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dhillon, Braham; Feau, Nicolas; Aerts, Andrea L.

Some of the most damaging tree diseases are caused by pathogens that induce cankers, a stem deformation often lethal. To investigate the cause of this adaptation, we sequenced the genomes of poplar pathogens that do and do not cause cankers. We found a unique cluster of genes that produce secondary metabolites and are co-activated when the canker pathogen is grown on poplar wood and leaves. The gene genealogy is discordant with the species phylogeny, showing a signature of horizontal transfer from fungi associated with wood decay. Furthermore, genes encoding hemicellulose-degrading enzymes are up-regulated on poplar wood chips, with some havingmore » been acquired horizontally. In conclusion, we propose that adaptation to colonize poplar woody stems is the result of acquisition of these genes.« less

Horizontal gene transfer and gene dosage drives adaptation to wood colonization in a tree pathogen

DOE PAGES

Dhillon, Braham; Feau, Nicolas; Aerts, Andrea L.; ...

2015-03-02

Some of the most damaging tree diseases are caused by pathogens that induce cankers, a stem deformation often lethal. To investigate the cause of this adaptation, we sequenced the genomes of poplar pathogens that do and do not cause cankers. We found a unique cluster of genes that produce secondary metabolites and are co-activated when the canker pathogen is grown on poplar wood and leaves. The gene genealogy is discordant with the species phylogeny, showing a signature of horizontal transfer from fungi associated with wood decay. Furthermore, genes encoding hemicellulose-degrading enzymes are up-regulated on poplar wood chips, with some havingmore » been acquired horizontally. In conclusion, we propose that adaptation to colonize poplar woody stems is the result of acquisition of these genes.« less

Genome analysis of Daldinia eschscholtzii strains UM 1400 and UM 1020, wood-decaying fungi isolated from human hosts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chan, Chai Ling; Yew, Su Mei; Ngeow, Yun Fong

Background: Daldinia eschscholtzii is a wood-inhabiting fungus that causes wood decay under certain conditions. It has a broad host range and produces a large repertoire of potentially bioactive compounds. However, there is no extensive genome analysis on this fungal species. Results: Two fungal isolates (UM 1400 and UM 1020) from human specimens were identified as Daldinia eschscholtzii by morphological features and ITS-based phylogenetic analysis. Both genomes were similar in size with 10,822 predicted genes in UM 1400 (35.8 Mb) and 11,120 predicted genes in UM 1020 (35.5 Mb). A total of 751 gene families were shared among both UM isolates,more » including gene families associated with fungus-host interactions. In the CAZyme comparative analysis, both genomes were found to contain arrays of CAZyme related to plant cell wall degradation. Genes encoding secreted peptidases were found in the genomes, which encode for the peptidases involved in the degradation of structural proteins in plant cell wall. In addition, arrays of secondary metabolite backbone genes were identified in both genomes, indicating of their potential to produce bioactive secondary metabolites. Both genomes also contained an abundance of gene encoding signaling components, with three proposed MAPK cascades involved in cell wall integrity, osmoregulation, and mating/filamentation. Besides genomic evidence for degrading capability, both isolates also harbored an array of genes encoding stress response proteins that are potentially significant for adaptation to living in the hostile environments. In conclusion: Our genomic studies provide further information for the biological understanding of the D. eschscholtzii and suggest that these wood-decaying fungi are also equipped for adaptation to adverse environments in the human host.« less

Genome analysis of Daldinia eschscholtzii strains UM 1400 and UM 1020, wood-decaying fungi isolated from human hosts

DOE PAGES

Chan, Chai Ling; Yew, Su Mei; Ngeow, Yun Fong; ...

2015-11-18

Background: Daldinia eschscholtzii is a wood-inhabiting fungus that causes wood decay under certain conditions. It has a broad host range and produces a large repertoire of potentially bioactive compounds. However, there is no extensive genome analysis on this fungal species. Results: Two fungal isolates (UM 1400 and UM 1020) from human specimens were identified as Daldinia eschscholtzii by morphological features and ITS-based phylogenetic analysis. Both genomes were similar in size with 10,822 predicted genes in UM 1400 (35.8 Mb) and 11,120 predicted genes in UM 1020 (35.5 Mb). A total of 751 gene families were shared among both UM isolates,more » including gene families associated with fungus-host interactions. In the CAZyme comparative analysis, both genomes were found to contain arrays of CAZyme related to plant cell wall degradation. Genes encoding secreted peptidases were found in the genomes, which encode for the peptidases involved in the degradation of structural proteins in plant cell wall. In addition, arrays of secondary metabolite backbone genes were identified in both genomes, indicating of their potential to produce bioactive secondary metabolites. Both genomes also contained an abundance of gene encoding signaling components, with three proposed MAPK cascades involved in cell wall integrity, osmoregulation, and mating/filamentation. Besides genomic evidence for degrading capability, both isolates also harbored an array of genes encoding stress response proteins that are potentially significant for adaptation to living in the hostile environments. In conclusion: Our genomic studies provide further information for the biological understanding of the D. eschscholtzii and suggest that these wood-decaying fungi are also equipped for adaptation to adverse environments in the human host.« less

Distinct Growth and Secretome Strategies for Two Taxonomically Divergent Brown Rot Fungi.

PubMed

Presley, Gerald N; Schilling, Jonathan S

2017-04-01

Brown rot fungi are wood-degrading fungi that employ both oxidative and hydrolytic mechanisms to degrade wood. Hydroxyl radicals that facilitate the oxidative component are powerful nonselective oxidants and are incompatible with hydrolytic enzymes unless they are spatially segregated in wood. Differential gene expression has been implicated in the segregation of these reactions in Postia placenta , but it is unclear if this two-step mechanism varies in other brown rot fungi with different traits and life history strategies that occupy different niches in nature. We employed proteomics to analyze a progression of wood decay on thin wafers, using brown rot fungi with significant taxonomic and niche distances: Serpula lacrymans (Boletales; "dry rot" lumber decay) and Gloeophyllum trabeum (order Gloeophyllales; slash, downed wood). Both fungi produced greater oxidoreductase diversity upon wood colonization and greater glycoside hydrolase activity later, consistent with a two-step mechanism. The two fungi invested very differently, however, in terms of growth (infrastructure) versus protein secretion (resource capture), with the ergosterol/extracted protein ratio being 7-fold higher with S. lacrymans than with G. trabeum In line with the native substrate associations of these fungi, hemicellulase-specific activities were dominated by mannanase in S. lacrymans and by xylanase in G. trabeum Consistent with previous observations, S. lacrymans did not produce glycoside hydrolase 6 (GH6) cellobiohydrolases (CBHs) in this study, despite taxonomically belonging to the order Boletales, which is distinguished among brown rot fungi by having CBH genes. This work suggests that distantly related brown rot fungi employ staggered mechanisms to degrade wood, but the underlying strategies vary among taxa. IMPORTANCE Wood-degrading fungi are important in forest nutrient cycling and offer promise in biotechnological applications. Brown rot fungi are unique among these fungi in that they use a nonenzymatic oxidative pretreatment before enzymatic carbohydrate hydrolysis, enabling selective removal of carbohydrates from lignin. This capacity has independently evolved multiple times, but it is unclear if different mechanisms underpin similar outcomes. Here, we grew fungi directionally on wood wafers and we found similar two-step mechanisms in taxonomically divergent brown rot fungi. The results, however, revealed strikingly different growth strategies, with S. lacrymans investing more in biomass production than secretion of proteins and G. trabeum showing the opposite pattern, with a high diversity of uncharacterized proteins. The "simplified" S. lacrymans secretomic system could help narrow gene targets central to oxidative brown rot pretreatments, and a comparison of its distinctions with G. trabeum and other brown rot fungi (e.g., Postia placenta ) might offer similar traction in noncatabolic genes. Copyright © 2017 American Society for Microbiology.

Chapter 5: Organopollutant Degradation by Wood Decay Basidiomycetes

Treesearch

Yitzhak Hadar; Daniel Cullen

2013-01-01

Wood decay fungi are obligate aerobes, deriving nutrients from the biological ‘combustion’ of wood, using molecular oxygen as terminal electron acceptor (Kirk and Farrell 1987; Blanchette 1991). Non-specific extracellular enzymes are generally viewed as key components in lignin depolymerization. The major enzymes implicated in lignin degradation are lignin peroxidase (...

Genomewide analysis of polysaccharides degrading enzymes in 11 white- and brown-rot Polyporales provides insight into mechanisms of wood decay

Treesearch

Chiaki Hori; Jill Gaskell; Kiyohiko Igarashi; Masahiro Samejima; David Hibbett; Bernard Henrissat; Dan Cullen

2013-01-01

To degrade the polysaccharides, wood-decay fungi secrete a variety of glycoside hydrolases (GHs) and carbohydrate esterases (CEs) classified into various sequence-based families of carbohydrate-active enzymes (CAZys) and their appended carbohydrate-binding modules (CBM). Oxidative enzymes, such as cellobiose dehydrogenase (CDH) and lytic polysaccharide monooxygenase (...

Tolerance of Serpula lacrymans to copper-based wood preservatives

Treesearch

Anne Christine Steenkjaer Hastrup; Frederick Green; Carol A. Clausen; Bo Jensen

2005-01-01

Serpula lacrymans, the dry rot fungus, is considered the most economically important wood decay fungus in certain temperate regions of the world, namely northern Europe, Japan, and Australia. Previously, copper-based wood preservatives were commonly used for pressure treatment of wood for building construction, but some decay fungi are known to be copper tolerant. In...

Gene expression analysis of wood decay fungus Fibroporia Radiculosa grown In ACQ-treated wood

Treesearch

Ayfer Akgul; Ali Akgul; Juliet D. Diehl Tang

2018-01-01

Copper-tolerant brown-rot fungi are able todegrade wood treated with copper or copper-based wood preservatives. This research used quantitative reverse transcriptase polymerase chain reaction to explore what genes of the brown-rot fungus, Fibroporia radiculosa, were expressed when the fungus was overcoming the wood preservatives and decaying the...

Changes in wood microstructure through progressive stages of decay

Treesearch

W. Wayne Wilcox

1968-01-01

Successive stages of decay in the sapwood of sweetgum (Liquidambar styraciflua L.), a hardwood, and of southern pine (Pinus sp.), a softwood, were observed microscopically. The white-rot fungus. Polyporus versicolor L., and the brown-rot fungus, Poria monticola Murr., were the fungi used or the observations, light microscopy, plus the techniques of polarization and...

Effect of inorganic nutrients on relative contributions of fungi and bacteria to carbon flow from submerged decomposing leaf litter

Treesearch

Vladislav Gulis; Keller Suberkropp

2003-01-01

The relative contributions of fungi and bacteria to carbon flow from submerged decaying plant litter at different levels of inorganic nutrients (N and P) were studied. We estimated leaf mass loss, fungal and bacterial biomass and production, and microbial respiration and constructed partial carbon budgets for red maple leaf disks precolonized in a stream and then...

Multicomponent biocide systems protect wood from decay fungi, mold fungi, and termites for interior applications

Treesearch

Carol A. Clausen; Vina W. Yang

2004-01-01

Concerns about indoor air quality due to mold growth have increased dramatically in the United States. In the absence of proper moisture management, fungicides need to be developed for indoor use to control mold establishment. An ideal fungicide for prevention of indoor mold growth on wood-based materials needs to specifically prevent spore germination and provide long...

Gene expression patterns of wood decay fungi Postia placenta and Phanerochaete chrysosporium are influenced by wood substrate composition during degradation

Treesearch

Oleksandr Skyba; Daniel Cullen; Carl J. Douglas; Shawn D. Mansfield

2016-01-01

Identification of the specific genes and enzymes involved in the fungal degradation of lignocellulosic biomass derived from feedstocks with various compositions is essential to the development of improved bioenergy processes. In order to elucidate the effect of substrate composition on gene expression in wood-rotting fungi, we employed microarrays based on the...

Hypholoma lateritium isolated from coarse woody debris, the forest floor, and mineral soil in a deciduous forest in New Hampshire

Treesearch

Therese A. Thompson; R. Greg Thorn; Kevin T. Smith

2012-01-01

Fungi in the Agaricomycetes (Basidiomycota) are the primary decomposers in temperate forests of dead wood on and in the forest soil. Through the use of isolation techniques selective for saprotrophic Agaricomycetes, a variety of wood decay fungi were isolated from a northern hardwood stand in the Bartlett Experimental Forest, New Hampshire, USA. In particular,

Enzymatic oxalic acid regulation correlated with wood degradation in four brown-rot fungi

Treesearch

Anne Christine Steenkjær Hastrup; Frederick Green III; Patricia K. Lebow; Bo Jensen

2012-01-01

Oxalic acid is a key component in the initiation of brown-rot decay and it has been suggested that it plays multiple roles during the degradation process. Oxalic acid is accumulated to varying degrees among brown-rot fungi; however, details on active regulation are scarce. The accumulation of oxalic acid was measured in this study from wood degraded by the four brown-...

Effect of fungal decay on the hygroscopic thickness swelling rate of lignocellulosic filler-polyolefin biocomposites

NASA Astrophysics Data System (ADS)

Kord, B.; Hosseinihashemi, S. Kh.

2014-01-01

The influence of fungal decay on the hygroscopic thickness swelling rate of lignocellulosic filler-polyolefin biocomposites has been investigated. Composites based on polypropylene (PP), bagasse fiber (BF), and a coupling agent (PP-g-MA) were made by melt compounding and injection molding. The weigt ratio of BF to PP was controlled at 60/40 for all blends. The amount of coupling agent was fixed at 2% for all formulations. The samples obtained were exposed to the action of brown-rot (Coniophora puteana) and white-rot (Trametes versicolor) fungi for 8, 12, and 16 weeks according to the Kolle-flask method. The thickness swelling of the samples was evaluated by immersing them in water at room temperature for several weeks. The morphology of the composites was characterized using the scanning electron microscopy (SEM). The results indicated that the fungal decay had an adverse affect on the dimensional stability of BF/PP composites due to an increase in the thickness swelling rate. The thickness swelling of white-rotted samples was higher than that of brown-rotted ones and control samples. Also, the thickness swelling of BF/PP composites increased with increasing time of fungal decay. In addition, after 16 weeks of exposure to white-rot fungi, the composites exhibited a higher parameter of swelling rate K SR than control samples. The K SR of the composites was influenced both by the type of rooting and the exposure time. Furthermore, the SEM micrographs showed that the extent of degradation increased with growing exposure time to fungi.

Chlorination of lignin by ubiquitous fungi has a likely role in global organochlorine production

PubMed Central

Ortiz-Bermúdez, Patricia; Hirth, Kolby C.; Srebotnik, Ewald; Hammel, Kenneth E.

2007-01-01

Soils and decayed plant litter contain significant quantities of chlorinated aromatic polymers that have a natural but largely unknown origin. We used cupric oxide ligninolysis coupled with gas chromatography/mass spectrometry to show that Curvularia inaequalis, a widely distributed litter ascomycete, chlorinated the aromatic rings of lignin in wood that it was degrading. In aspen wood decayed for 24 weeks, two chlorolignin fragments, 5-chlorovanillin and 2-chlorosyringaldehyde, were each found at ≈10 μg/g of wood (dry weight). These levels resemble those of similar structures generally found in unpolluted environmental samples. Fractionation of the extractable proteins followed by tandem mass spectrometric analysis showed that the colonized wood contained a previously described C. inaequalis chloroperoxidase that very likely catalyzed lignin chlorination. Chlorolignin produced by this route and humus derived from it are probably significant components of the global chlorine cycle because chloroperoxidase-producing fungi are ubiquitous in decaying lignocellulose and lignin is the earth's most abundant aromatic substance. PMID:17360449

Dimensional stability and decay resistance of composite fiberboard made from plantation-grown southern yellow pine

Treesearch

Poo Chow; Timothy Harp; John A. Youngquist; Jim H. Muehl; Andrzej M. Krzysik

1999-01-01

The objective of this study was to investigate the influence of the phenol-formaldehyde resin content level (3 percent and 7 percent), and three fungi species (Poria placenta, Gleophyllum trabeum, and Polyporus versicolor) on the dimensional stability and decay resistance of high density composition boards made from plantation-grown southern pine chips. A standard ASTM...

Potential of decaying wood to restore root-available base cations in depleted forest soils

Treesearch

Walter C. Shortle; Kevin T. Smith; Jody Jellison; Jonathan S. Schilling

2012-01-01

The depletion of root-available Ca in northern forest soils exposed to decades of increased acid deposition adversely affects forest health and productivity. Laboratory studies indicated the potential of wood-decay fungi to restore lost Ca. This study presents changes in concentration of Ca, Mg, and K in sapwood of red spruce (Picea rubens Sarg.),...

Transcriptome and secretome analyses of the wood decay fungus Wolfiporia cocos support alternative mechanisms of lignocellulose conversion

Treesearch

Jill Gaskell; Robert A. Blanchette; Philip E. Stewart; Sandra Splinter BonDurant; Marie Adams; Grzegorz Sabat; Philip Kersten; Daniel Cullen

2016-01-01

Certain wood decay basidiomycetes, collectively referred to as brown rot fungi, rapidly depolymerize cellulose while leaving behind the bulk of cell wall lignin as a modified residue. The mechanism(s) employed is unclear, but considerable evidence implicates the involvement of diffusible oxidants generated via Fenton-like chemistry. Toward a better understanding of...

Genome, transcriptome, and secretome analysis of wood decay fungus Postia placenta supports unique mechanisms of lignocellulose conversion

Treesearch

Diego Martinez; Jean Challacombe; Ingo Morgenstern; David Hibbett; Monika Schmoll; Christian P. Kubicek; Patricia Ferreira; Francisco J. Ruiz-Duenas; Angel T. Martinez; Philip J. Kersten; Kenneth E. Hammel; Jill A. Gaskell; Daniel Cullen

2009-01-01

Brown-rot fungi such as Postia placenta are common inhabitants of forest ecosystems and are also largely responsible for the destructive decay of wooden structures. Rapid depolymerization of cellulose is a distinguishing feature of brown-rot, but the biochemical mechanisms and underlying genetics are poorly understood. Systematic examination of the P. placenta genome,...

Wood decay by Chlorociboria aeruginascens (Nyl.) Kanouse (Helotiales, Leotiaceae) and associated basidiomycete fungi

Treesearch

Dana L. Richter; Jessie A. Glaeser

2015-01-01

Two isolates of Chlorociboria aeruginascens (Nyl.) Kanouse incubated axenically on aspen wood blocks resulted in 18% and 32% mass loss after 134 wks (2 yrs 8 mo). Aspen wood decayed by C. aeruginascens contained cavities in the S2 layer of the secondary cell wall, similar to Type I soft rot attack, as well as erosion troughs and...

Occurrence of Platypus mutatus Chapuis (Coleoptera: Platypodidae) in a brazilwood experimental plantation in Southeastern Brazil.

PubMed

Girardi, Graziele S; Giménez, Rosana A; Braga, Márcia R

2006-01-01

The hardwood of Caesalpinia echinata Lam. (brazilwood, Pernambuco, ibirapitanga) is currently the most profitable material used for violin bow due to the unique vibrational properties and dimensional stability. Although this species is resistant to the wood decay caused by termites and rot fungi, an experimental plantation in Southeastern Brazil has been attacked by the ambrosia beetle Platypus mutatus Chapuis (= Megaplatypus mutatus and P. sulcatus). This species invaded ca. 3% of the individuals, mainly in the central part of the plantation. Infestation by larvae and adults was higher during the dry season (winter) when compared to the rainy period (spring and summer).

The role of oxalic acid in tolerance to N’N-napthaloylhydroxylamine in Tyromyces palustris

Treesearch

R.A. Arango; C.A. Clausen; Frederick Green

2006-01-01

Certain wood decay fungi exhibit tolerance to one or more wood preservatives. Copper tolerance of brown-rot fungi has been studied in our laboratory for the past six years. We have observed some degree of tolerance to N’N-naphthaloylhydroxamine (NHA), a recently patented termite bait, by the brown-rot fungus Tyromyces palustris TYP-6137. In an effort to try and confirm...

Selection and validation of enzymatic activities as functional markers in wood biotechnology and fungal ecology.

PubMed

Mathieu, Yann; Gelhaye, Eric; Dumarçay, Stéphane; Gérardin, Philippe; Harvengt, Luc; Buée, Marc

2013-02-15

The dead wood and forest soils are sources of diversity and under-explored fungal strains with biotechnological potential, which require to be studied. Numerous enzymatic tests have been proposed to investigate the functional potential of the soil microbial communities or to test the functional abilities of fungal strains. Nevertheless, the diversity of these functional markers and their relevance in environmental studies or biotechnological screening does still have not been demonstrated. In this work, we assessed ten different extracellular enzymatic activities involved in the wood decaying process including β-etherase that specifically cleaves the β-aryl ether linkages in the lignin polymer. For this purpose, a collection of 26 fungal strains, distributed within three ecological groups (white, brown and soft rot fungi), has been used. Among the ten potential functional markers, the combinatorial use of only six of them allowed separation between the group of white and soft rot fungi from the brown rot fungi. Moreover, our results suggest that extracellular β-etherase is a rare and dispensable activity among the wood decay fungi. Finally, we propose that this set of markers could be useful for the analysis of fungal communities in functional and environmental studies, and for the selection of strains with biotechnological interests. Copyright © 2012 Elsevier B.V. All rights reserved.

Potential of Wood-Rotting Fungi to Attack Polystyrene Sulfonate and Its Depolymerisation by Gloeophyllum trabeum via Hydroquinone-Driven Fenton Chemistry

PubMed Central

Krueger, Martin C.; Hofmann, Ulrike; Moeder, Monika; Schlosser, Dietmar

2015-01-01

Synthetic polymers often pose environmental hazards due to low biodegradation rates and resulting accumulation. In this study, a selection of wood-rotting fungi representing different lignocellulose decay types was screened for oxidative biodegradation of the polymer polystyrene sulfonate (PSS). Brown-rot basidiomycetes showed PSS depolymerisation of up to 50 % reduction in number-average molecular mass (Mn) within 20 days. In-depth investigations with the most efficient depolymeriser, a Gloeophyllum trabeum strain, pointed at extracellular hydroquinone-driven Fenton chemistry responsible for depolymerisation. Detection of hydroxyl radicals present in the culture supernatants showed good compliance with depolymerisation over the time course of PSS degradation. 2,5-Dimethoxy-1,4-hydroquinone (2,5-DMHQ), which was detected in supernatants of active cultures via liquid chromatography and mass spectrometry, was demonstrated to drive the Fenton processes in G. trabeum cultures. Up to 80% reduction in Mn of PSS where observed when fungal cultures were additionally supplemented with 2,5-dimethoxy benzoquinone, the oxidized from of 2,5-DMHQ. Furthermore, 2,5-DMHQ could initiate the Fenton's reagent-mediated PSS depolymerisation in cell-free systems. In contrast, white-rot fungi were unable to cause substantial depolymerising effects despite the expression of lignin-modifying exo-enzymes. Detailed investigations with laccase from Trametes versicolor revealed that only in presence of certain redox mediators limited PSS depolymerisation occurred. Our results indicate that brown-rot fungi might be suitable organisms for the biodegradation of recalcitrant synthetic polymeric pollutants. PMID:26147966

Mucormycosis

MedlinePlus

... fungi that are often found in decaying organic matter. These include spoiled bread, fruit, and vegetables, as ... include: Eyes that swell and stick out (protrude) Dark scabbing in nasal cavities Fever Headache Mental status ...

Rapid polyether cleavage via extracellular one-electron oxidation by a brown-rot basidiomycete.

PubMed

Kerem, Z; Bao, W; Hammel, K E

1998-09-01

Fungi that cause brown rot of wood are essential biomass recyclers and also the principal agents of decay in wooden structures, but the extracellular mechanisms by which they degrade lignocellulose remain unknown. To test the hypothesis that brown-rot fungi use extracellular free radical oxidants as biodegradative tools, Gloeophyllum trabeum was examined for its ability to depolymerize an environmentally recalcitrant polyether, poly(ethylene oxide) (PEO), that cannot penetrate cell membranes. Analyses of degraded PEOs by gel permeation chromatography showed that the fungus cleaved PEO rapidly by an endo route. 13C NMR analyses of unlabeled and perdeuterated PEOs recovered from G. trabeum cultures showed that a major route for depolymerization was oxidative C---C bond cleavage, a reaction diagnostic for hydrogen abstraction from a PEO methylene group by a radical oxidant. Fenton reagent (Fe(II)/H2O2) oxidized PEO by the same route in vitro and therefore might account for PEO biodegradation if it is produced by the fungus, but the data do not rule out involvement of less reactive radicals. The reactivity and extrahyphal location of this PEO-degrading system suggest that its natural function is to participate in the brown rot of wood and that it may enable brown-rot fungi to degrade recalcitrant organopollutants.

Long-term priority effects among insects and fungi colonizing decaying wood.

PubMed

Weslien, Jan; Djupström, Line B; Schroeder, Martin; Widenfalk, Olof

2011-11-01

1. Priority effects have been hypothesized to have long-lasting impact on community structure in natural ecosystems. Long-term studies of priority effects in natural ecosystems are however sparse, especially in terrestrial ecosystems. 2. Wood decay is a slow process involving a high diversity of insect and fungus species. Species interactions that drive change in communities of insects and fungi during wood decay are poorly understood because of a lack of sufficient long-term studies. 3. In this paper, we followed the colonization and succession of wood-living insects and fungi on cut trees during 15 years, from tree death and onwards, in a boreal forest landscape. We test the long-term priority effects hypothesis that the identity and abundance of species that colonize first affect the colonization success of later-arriving species. We also hypothesize that species interact in both facilitative and inhibitory ways, which ultimately affect habitat quality for a red-listed late-succession beetle species. 4. Possible causal associations between species were explored by path analysis. The results indicate that one bark beetle species, Hylurgops palliatus, and one wood-borer species, Monochamus sutor, which colonized the wood during the first year after cutting, influenced the occurrence of a rare, wood-living beetle, Peltis grossa, that started to emerge from the stumps about 10 years later. The positive effects of Hylurgops palliatus and negative effects of M. sutor were largely mediated through the wood-decaying fungus species Fomitopsis pinicola. 5. The study shows that variable priority effects may have long-lasting impact on community assembly in decaying wood. The study also exemplifies new possibilities for managing populations of threatened species by exploring links between early, well-understood species guilds and late, more poorly understood species guilds. © 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society.

Resistance of 22 southern hardwoods to wood-decay fungi and subterranean termites

Treesearch

F.Y. Carter; T.L. Amburgey; F.G. Manwiller

1976-01-01

Of 22 hardwood species growing on southern pine sites, blackjack, white, and post oaks proved most resistant to attack by the brown-rot fungus, Lenzites trabea. The amount of decay ranged from 8 percent for blackjack and white oak to 67 percent for red maple. Winged elm, yellow-poplar, and post, black, white, and southern red oaks were the most...

The Paleozoic Origin of Enzymatic Lignin Decomposition Reconstructed from 31 Fungal Genomes

Treesearch

Dimitrios Floudas; Manfred Binder; Robert Riely; Kerrie Barry; Robert A. Blanchette; Bernard Henrissat; Angel T. Martínez; Robert Otillar; Joseph W. Spatafora; Jagjit S. Yadav; Andrea Aerts; Isabelle Benoit; Alex Boyd; Alexis Carlson; Alex Copeland; Pedro M. Coutinho; Ronald P. deVries; Patricia Ferreira; Keisha Findley; Brian Foster; Jill Gaskell; Dylan Glotzer; Pawe³ Górecki; Joseph Heitman; Cedar Hesse; Chiaki Hori; Kiyohiko Igarashi; Joel A. Jurgens; Nathan Kallen; Phil Kersten; Annegret Kohler; Ursula Kües; T. K. ArunKumar; Alan Kuo; Kurt LaButti; Luis F. Larrondo; Erika Lindquist; Albee Ling; Vincent Lombard; Susan Lucas; Taina Lundell; Rachael Martin; David J. McLaughlin; Ingo Morgenstern; Emanuelle Morin; Claude Murat; Laszlo G. Nagy; Matt Nolan; Robin A. Ohm; Aleksandrina Patyshakuliyeva; Antonis Rokas; Francisco J. Ruiz-Dueñas; Grzegorz Sabat; Asaf Salamov; Masahiro Samejima; Jeremy Schmutz; Jason C. Slot; Franz St. John; Jan Stenlid; Hui Sun; Sheng Sun; Khajamohiddin Syed; Adrian Tsang; Ad Wiebenga; Darcy Young; Antonio Pisabarro; Daniel C. Eastwood; Francis Martin; Dan Cullen; Igor V. Grigoriev; David S. Hibbett

2012-01-01

Wood is a major pool of organic carbon that is highly resistant to decay, owing largely to the presence of lignin. The only organisms capable of substantial lignin decay are white rot fungi in the Agaricomycetes, which also contains non–lignin-degrading brown rot and ectomycorrhizal species. Comparative analyses of 31 fungal genomes (12 generated for this study)...

Wolfiporia cocos : a potential agent for composting of bioprocessing Douglas-fir wood treated with copper-based preservatives

Treesearch

Rodney. De Groot; Bessie. Woodward

1998-01-01

In laboratory experiments, Douglas-fir wood blocks that were treated with copper- based wood preservatives were challenged with two wood decay fungi known to be tolerant of copper. Factors influencing the amount of decay, as determined by loss of weight in the test blocks, were preservative, then fungus. Within those combinations, the relative importance of...

Assessing the impact of wood decay fungi on the modulus of elasticity of slash pine (Pinus elliottii) by stress wave non-destructive testing

Treesearch

Zhong Yang; Zhehui Jiang; Chung Y. Hse; Ru Liu

2017-01-01

Small wood specimens selected from six slash pine (Pinus elliottii) trees were inoculated with brown-rot and white-rot fungi and then evaluated for static modulus of elasticity (MOE) and dynamic MOE (MOEsw). The experimental variables studied included a brown-rot fungus (Gloeophyllum trabeum) and a white-rot fungus (Trametes versicolor) for six exposure periods (2, 4,...

The GSTome Reflects the Chemical Environment of White-Rot Fungi

PubMed Central

Deroy, Aurélie; Saiag, Fanny; Kebbi-Benkeder, Zineb; Touahri, Nassim; Hecker, Arnaud; Morel-Rouhier, Mélanie; Colin, Francis; Dumarcay, Stephane; Gérardin, Philippe; Gelhaye, Eric

2015-01-01

White-rot fungi possess the unique ability to degrade and mineralize all the different components of wood. In other respects, wood durability, among other factors, is due to the presence of extractives that are potential antimicrobial molecules. To cope with these molecules, wood decay fungi have developed a complex detoxification network including glutathione transferases (GST). The interactions between GSTs from two white-rot fungi, Trametes versicolor and Phanerochaete chrysosporium, and an environmental library of wood extracts have been studied. The results demonstrate that the specificity of these interactions is closely related to the chemical composition of the extracts in accordance with the tree species and their localization inside the wood (sapwood vs heartwood vs knotwood). These data suggest that the fungal GSTome could reflect the chemical environment encountered by these fungi during wood degradation and could be a way to study their adaptation to their way of life. PMID:26426695

Fungal Transformation of Tree Stumps into a Suitable Resource for Xylophagous Beetles via Changes in Elemental Ratios

PubMed Central

Filipiak, Michał; Sobczyk, Łukasz; Weiner, January

2016-01-01

The elements present in dead pine stumps inhabited by larvae of wood-boring beetles (Stictoleptura rubra, Arhopalus rusticus and Chalcophora mariana) were analyzed over the initial (first 5 years; a chronosequence) stages of wood decay. The quantities of N, P, K, Ca, Mg, Fe, Zn, Mn, Cu and Na (but not S) increased with increases in the content of ergosterol (used as a proxy for the amount of fungal tissue). In fact, the amounts of P, N, K, Fe and Cu presented marked increases. These findings show that fungi stoichiometrically rearrange dead wood by importing externally occurring nutrients to decaying stumps. During the first years of wood decay, the ratios of C to other elements decrease substantially, but differently, for various elements, whereas the N:Fe, N:Cu, N:P and N:K ratios remain relatively stable. Therefore, the stoichiometric mismatch between xylophages and their food is greatly reduced. By changing the nutritional stoichiometry of dead wood, fungi create a nutritional niche for wood-eaters, and these changes enable the development of xylophages.

Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kohler, Annegret; Kuo, Alan; Nagy, Laszlo G.

To elucidate the genetic bases of mycorrhizal lifestyle evolution, we sequenced new fungal genomes, including 13 ectomycorrhizal (ECM), orchid (ORM) and ericoid (ERM) species, and five saprotrophs, which we analyzed along with other fungal genomes. Ectomycorrhizal fungi have a reduced complement of genes encoding plant cell wall-degrading enzymes (PCWDEs), as compared to their ancestral wood decayers. Nevertheless, they have retained a unique array of PCWDEs, thus suggesting that they possess diverse abilities to decompose lignocellulose. Similar functional categories of nonorthologous genes are induced in symbiosis. Of induced genes, 7-38% are orphan genes, including genes that encode secreted effector-like proteins. Convergentmore » evolution of the mycorrhizal habit in fungi occurred via the repeated evolution of a 'symbiosis toolkit', with reduced numbers of PCWDEs and lineage-specific suites of mycorrhiza-induced genes.« less

Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists

DOE PAGES

Kohler, Annegret; Kuo, Alan; Nagy, Laszlo G.; ...

2015-02-23

To elucidate the genetic bases of mycorrhizal lifestyle evolution, we sequenced new fungal genomes, including 13 ectomycorrhizal (ECM), orchid (ORM) and ericoid (ERM) species, and five saprotrophs, which we analyzed along with other fungal genomes. Ectomycorrhizal fungi have a reduced complement of genes encoding plant cell wall-degrading enzymes (PCWDEs), as compared to their ancestral wood decayers. Nevertheless, they have retained a unique array of PCWDEs, thus suggesting that they possess diverse abilities to decompose lignocellulose. Similar functional categories of nonorthologous genes are induced in symbiosis. Of induced genes, 7-38% are orphan genes, including genes that encode secreted effector-like proteins. Convergentmore » evolution of the mycorrhizal habit in fungi occurred via the repeated evolution of a 'symbiosis toolkit', with reduced numbers of PCWDEs and lineage-specific suites of mycorrhiza-induced genes.« less

Decay fungi of riparian trees in the Southwestern U.S.

Treesearch

Jessie A. Glaeser; Kevin T. Smith

2013-01-01

Most of the tree species that characterize riparian woodlands are early or facultative seral species including Fremont cottonwood (Populus fremontii), Arizona alder (Alnus oblongifolia), Arizona sycamore (Platanus wrightii), Modesto ash (Fraxinus velutina), boxelder (Acer negundo...

The importance of associations with saprotrophic non-Rhizoctonia fungi among fully mycoheterotrophic orchids is currently under-estimated: novel evidence from sub-tropical Asia

PubMed Central

Lee, Yung-I; Yang, Chih-Kai; Gebauer, Gerhard

2015-01-01

Background and Aims Most fully mycoheterotrophic (MH) orchids investigated to date are mycorrhizal with fungi that simultaneously form ectomycorrhizas with forest trees. Only a few MH orchids are currently known to be mycorrhizal with saprotrophic, mostly wood-decomposing, fungi instead of ectomycorrhizal fungi. This study provides evidence that the importance of associations between MH orchids and saprotrophic non-Rhizoctonia fungi is currently under-estimated. Methods Using microscopic techniques and molecular approaches, mycorrhizal fungi were localized and identified for seven MH orchid species from four genera and two subfamilies, Vanilloideae and Epidendroideae, growing in four humid and warm sub-tropical forests in Taiwan. Carbon and nitrogen stable isotope natural abundances of MH orchids and autotrophic reference plants were used in order to elucidate the nutritional resources utilized by the orchids. Key Results Six out of the seven MH orchid species were mycorrhizal with either wood- or litter-decaying saprotrophic fungi. Only one orchid species was associated with ectomycorrhizal fungi. Stable isotope abundance patterns showed significant distinctions between orchids mycorrhizal with the three groups of fungal hosts. Conclusions Mycoheterotrophic orchids utilizing saprotrophic non-Rhizoctonia fungi as a carbon and nutrient source are clearly more frequent than hitherto assumed. On the basis of this kind of nutrition, orchids can thrive in deeply shaded, light-limiting forest understoreys even without support from ectomycorrhizal fungi. Sub-tropical East Asia appears to be a hotspot for orchids mycorrhizal with saprotrophic non-Rhizoctonia fungi. PMID:26113634

Interactions affect hyphal growth and enzyme profiles in combinations of coniferous wood-decaying fungi of Agaricomycetes

PubMed Central

Mali, Tuulia; Kuuskeri, Jaana; Shah, Firoz

2017-01-01

Fomitopsis pinicola is a species of Polyporales frequently encountered in Nordic temperate and boreal forests. In nature, the fungus causes destructive brown rot in wood, colonizing tree trunks often occupied by other Basidiomycota species. We mimicked these species-species interactions by introducing F. pinicola to five white rot species, all common saprotrophs of Norway spruce. Hyphal interactions and mycelial growth in various combinations were recorded, while activities of lignocellulose-acting CAZymes and oxidoreductases were followed in co-cultures on two different carbon-source media. Of the species, Phlebia radiata and Trichaptum abietinum were the strongest producers of lignin-modifying oxidoreductases (laccase, manganese peroxidase) when evaluated alone, as well as in co-cultures, on the two different growth media (low-nitrogen liquid medium containing ground coniferous wood, and malt extract broth). F. pinicola was an outstanding producer of oxalic acid (up to 61 mM), whereas presence of P. radiata prevented acidification of the growth environment in the liquid malt-extract cultures. When enzyme profiles of the species combinations were clustered, time-dependent changes were observed on wood-supplemented medium during the eight weeks of growth. End-point acidity and production of mycelium, oxalic acid and oxidoreductase activities, in turn clustered the fungal combinations into three distinct functional groups, determined by the presence of F. pinicola and P. radiata, by principal component analysis. Our findings indicate that combinations of wood-decay fungi have dramatic dynamic effects on the production of lignocellulose-active enzymes, which may lead to divergent degradative processes of dead wood and forest litter. PMID:28953947

Interactions affect hyphal growth and enzyme profiles in combinations of coniferous wood-decaying fungi of Agaricomycetes.

PubMed

Mali, Tuulia; Kuuskeri, Jaana; Shah, Firoz; Lundell, Taina Kristina

2017-01-01

Fomitopsis pinicola is a species of Polyporales frequently encountered in Nordic temperate and boreal forests. In nature, the fungus causes destructive brown rot in wood, colonizing tree trunks often occupied by other Basidiomycota species. We mimicked these species-species interactions by introducing F. pinicola to five white rot species, all common saprotrophs of Norway spruce. Hyphal interactions and mycelial growth in various combinations were recorded, while activities of lignocellulose-acting CAZymes and oxidoreductases were followed in co-cultures on two different carbon-source media. Of the species, Phlebia radiata and Trichaptum abietinum were the strongest producers of lignin-modifying oxidoreductases (laccase, manganese peroxidase) when evaluated alone, as well as in co-cultures, on the two different growth media (low-nitrogen liquid medium containing ground coniferous wood, and malt extract broth). F. pinicola was an outstanding producer of oxalic acid (up to 61 mM), whereas presence of P. radiata prevented acidification of the growth environment in the liquid malt-extract cultures. When enzyme profiles of the species combinations were clustered, time-dependent changes were observed on wood-supplemented medium during the eight weeks of growth. End-point acidity and production of mycelium, oxalic acid and oxidoreductase activities, in turn clustered the fungal combinations into three distinct functional groups, determined by the presence of F. pinicola and P. radiata, by principal component analysis. Our findings indicate that combinations of wood-decay fungi have dramatic dynamic effects on the production of lignocellulose-active enzymes, which may lead to divergent degradative processes of dead wood and forest litter.

Revealing hidden insect-fungus interactions; moderately specialized, modular and anti-nested detritivore networks.

PubMed

Jacobsen, Rannveig M; Sverdrup-Thygeson, Anne; Kauserud, Håvard; Birkemoe, Tone

2018-04-11

Ecological networks are composed of interacting communities that influence ecosystem structure and function. Fungi are the driving force for ecosystem processes such as decomposition and carbon sequestration in terrestrial habitats, and are strongly influenced by interactions with invertebrates. Yet, interactions in detritivore communities have rarely been considered from a network perspective. In the present study, we analyse the interaction networks between three functional guilds of fungi and insects sampled from dead wood. Using DNA metabarcoding to identify fungi, we reveal a diversity of interactions differing in specificity in the detritivore networks, involving three guilds of fungi. Plant pathogenic fungi were relatively unspecialized in their interactions with insects inhabiting dead wood, while interactions between the insects and wood-decay fungi exhibited the highest degree of specialization, which was similar to estimates for animal-mediated seed dispersal networks in previous studies. The low degree of specialization for insect symbiont fungi was unexpected. In general, the pooled insect-fungus networks were significantly more specialized, more modular and less nested than randomized networks. Thus, the detritivore networks had an unusual anti-nested structure. Future studies might corroborate whether this is a common aspect of networks based on interactions with fungi, possibly owing to their often intense competition for substrate. © 2018 The Author(s).

Modification of the nanostructure of lignocellulose cell walls via a non-enzymatic lignocellulose deconstruction system in brown rot wood-decay fungi.

PubMed

Goodell, Barry; Zhu, Yuan; Kim, Seong; Kafle, Kabindra; Eastwood, Daniel; Daniel, Geoffrey; Jellison, Jody; Yoshida, Makoto; Groom, Leslie; Pingali, Sai Venkatesh; O'Neill, Hugh

2017-01-01

Wood decayed by brown rot fungi and wood treated with the chelator-mediated Fenton (CMF) reaction, either alone or together with a cellulose enzyme cocktail, was analyzed by small angle neutron scattering (SANS), sum frequency generation (SFG) spectroscopy, Fourier transform infrared (FTIR) analysis, X-ray diffraction (XRD), atomic force microscopy (AFM), and transmission electron microscopy (TEM). Results showed that the CMF mechanism mimicked brown rot fungal attack for both holocellulose and lignin components of the wood. Crystalline cellulose and lignin were both depolymerized by the CMF reaction. Porosity of the softwood cell wall did not increase during CMF treatment, enzymes secreted by the fungi did not penetrate the decayed wood. The enzymes in the cellulose cocktail also did not appear to alter the effects of the CMF-treated wood relative to enhancing cell wall deconstruction. This suggests a rethinking of current brown rot decay models and supports a model where monomeric sugars and oligosaccharides diffuse from the softwood cell walls during non-enzymatic action. In this regard, the CMF mechanism should not be thought of as a "pretreatment" used to permit enzymatic penetration into softwood cell walls, but instead it enhances polysaccharide components diffusing to fungal enzymes located in wood cell lumen environments during decay. SANS and other data are consistent with a model for repolymerization and aggregation of at least some portion of the lignin within the cell wall, and this is supported by AFM and TEM data. The data suggest that new approaches for conversion of wood substrates to platform chemicals in biorefineries could be achieved using the CMF mechanism with >75% solubilization of lignocellulose, but that a more selective suite of enzymes and other downstream treatments may be required to work when using CMF deconstruction technology. Strategies to enhance polysaccharide release from lignocellulose substrates for enhanced enzymatic action and fermentation of the released fraction would also aid in the efficient recovery of the more uniform modified lignin fraction that the CMF reaction generates to enhance biorefinery profitability.

Miscellaneous fungal diseases

USGS Publications Warehouse

Friend, M.

1999-01-01

As for other types of disease, fungal infections probably are more common causes of disease in wild birds than is currently recognized. Also, the similarity in gross lesions produced by some fungi mask the detection of less common fungi as disease agents. Numerous types of disease-causing fungi in addition to Aspergillus fumigatus and Candida albicans have been isolated from birds; most isolations have been from poultry and wild birds being maintained in captivity. Enhanced disease surveillance that is often associated with privately owned birds and greater opportunity to detect disease in confined birds are reasons for these findings rather than any known differences in the occurrence of fungal diseases in free-ranging and captive birds. Many of the reported infections appear to have been opportunistic invasions by the fungi involved. The important points are that many fungi are capable of causing disease in birds but their collective impacts do not rival A. fumigatus as a single cause of disease in wild birds. Nevertheless, it is important to be aware of the diversity of pathogenic or disease causing fungi.

EFFECT OF GAMMA RADIATION, CHEMICAL, AND PACKAGING TREATMENTS ON REFRIGERATED LIFE OF STRAWBERRIES AND SWEET CHERRIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cooper, G.M.; Salunkhe, D.K.

1963-06-01

After preirradiation chemical treatments and/or packaging in films, the fruits were sealed in perforated cans and irradiated at the Materials Test Reactor Station, Arco, Idaho, with spent-fuel rods of U/sup 235/. The doses were: strawberries 1, 2, and 3 x 10/sup 5/ rad; and cherries 2, 3, and 4 x 10/sup 5/ rad. Fruits were aerated during irradiation and then placed in storage at 40 deg F and 80% relative humidity for various periods. The cans were then opened; the percentage of marketable fruits was calculated, and fungi infecting the fruits were identified. The following results were obtained with strawberries.more » A dose of 2 x 10/sup 5/ rad was optimum for radiopasteurization; shelf-life was extentded approximates 15 days at tissue caused the berries to have a spongy, water-soaked texture. Captan proved a better fungus-inhibiting chemical than potassium sorbate when used with radiation. Hormodendrum and Botryis were the most common fungi; Penicillium was killed in all irradiated treatments. Varieties such as Kasuga, Lindalicious, and Sparkle, when harvested at the firm- ripe stage of maturity and then irradiated kept better tham other varieties. With sweet cherries it was found that a dose of 3 x 10/sup 6/ rad was effective in extending shelf-life beyond 30 days. Cherries turned brown at the high (4 x 10/sup 5/-rad) dose; however, pigment development and ripening were progressively retarded in all irradiated samples. Fungus control was better with Myprozine, captan, and Mycostatin than with other chemicals used with radiation. Storage life increased significantly when Mylar packaging was combined with radiation and chemical treatments. Alternaria was the most prevalent fungus growth; Penicillium was not observed. Bing, Lambert, and Windsor varieties responded better to radiopasteurization than did Napoleon. With some varieties of cherries, deterioration of the fruit was greater after low doses tham in the absence of irradiation, which indicates that radiation causes certain physical or chemical changes in some varieties thus enabling fungi to grow readily. At lower doses, this effect apparently fosters fungus growth sufficiently to more than compensate for the fewer organisms present initially. At higher radiation doses, the probability of eliminating all fungi increases, and more fruits may be totally free of fungus regardless of growth-promoting factors. It appeared that Penicillium mold is inhibited by gamma radiation, and that the main causes of decay at higher doses were the multicellular-spored fungi, which have greater resistance to gamma radiation than the unicellular conidia of Penicillium. (BBB)« less

Wood and humus decay strategies by white-rot basidiomycetes correlate with two different dye decolorization and enzyme secretion patterns on agar plates.

PubMed

Barrasa, José M; Blanco, María N; Esteve-Raventós, Fernando; Altés, Alberto; Checa, Julia; Martínez, Angel T; Ruiz-Dueñas, Francisco J

2014-11-01

During several forays for ligninolytic fungi in different Spanish native forests, 35 white-rot basidiomycetes growing on dead wood (16 species from 12 genera) and leaf litter (19 species from 10 genera) were selected for their ability to decolorize two recalcitrant aromatic dyes (Reactive Blue 38 and Reactive Black 5) added to malt extract agar medium. In this study, two dye decolorization patterns were observed and correlated with two ecophysiological groups (wood and humus white-rot basidiomycetes) and three taxonomical groups (orders Polyporales, Hymenochaetales and Agaricales). Depending on the above groups, different decolorization zones were observed on the dye-containing plates, being restricted to the colony area or extending to the surrounding medium, which suggested two different decay strategies. These two strategies were related to the ability to secrete peroxidases and laccases inside (white-rot wood Polyporales, Hymenochaetales and Agaricales) and outside (white-rot humus Agaricales) of the fungal colony, as revealed by enzymatic tests performed directly on the agar plates. Similar oxidoreductases production patterns were observed when fungi were grown in the absence of dyes, although the set of enzyme released was different. All these results suggest that the decolorization patterns observed could be related with the existence of two decay strategies developed by white-rot basidiomycetes adapted to wood and leaf litter decay in the field. Published by Elsevier Inc.

Comparative Genome Analysis of Basidiomycete Fungi

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riley, Robert; Salamov, Asaf; Morin, Emmanuelle

Fungi of the phylum Basidiomycota (basidiomycetes), make up some 37percent of the described fungi, and are important in forestry, agriculture, medicine, and bioenergy. This diverse phylum includes the mushrooms, wood rots, symbionts, and plant and animal pathogens. To better understand the diversity of phenotypes in basidiomycetes, we performed a comparative analysis of 35 basidiomycete fungi spanning the diversity of the phylum. Phylogenetic patterns of lignocellulose degrading genes suggest a continuum rather than a sharp dichotomy between the white rot and brown rot modes of wood decay. Patterns of secondary metabolic enzymes give additional insight into the broad array of phenotypesmore » found in the basidiomycetes. We suggest that the profile of an organism in lignocellulose-targeting genes can be used to predict its nutritional mode, and predict Dacryopinax sp. as a brown rot; Botryobasidium botryosum and Jaapia argillacea as white rots.« less

Leaf litter decomposition in Torna stream before and after a red mud disaster.

PubMed

Kucserka, T; Karádi-Kovács, Kata; Vass, M; Selmeczy, G B; Hubai, Katalin Eszter; Üveges, Viktória; Kacsala, I; Törő, N; Padisák, Judit

2014-03-01

The aim of the study was to estimate the breakdown of the allochthonous litter in an artificial stream running in an agricultural area and compare it with the same values following a toxic mud spill into the same stream. Litter bags were filled with three types of leaves (Quercus robur, Populus tremula and Salix alba) and placed to the bottom of the river. Ergosterol was used to detect fungal biomass. We supposed the absence of fungi and the retardation of leaf litter decomposition. Only pH and conductivity increased significantly. Leaf mass loss after the catastrophe was much slower than in 2009 and the decay curves did not follow the exponential decay model. Prior to the catastrophe, leaf mass loss was fast in Torna, compared to other streams in the area. The reason is that the stream is modified, the bed is trapezoid and covered with concrete stones. Fungal biomass was lower, than in the pre-disaster experiment, because fungi did not have enough leaves to sporulate. Leaf mass loss followed the exponential decay curve before the disaster, but after that it was possible only after a non-change period.

Significance of wood terpenoids in the resistance of Scots pine provenances against the old house borer, Hylotrupes bajulus, and brown-rot fungus, Coniophora puteana.

PubMed

Nerg, A M; Heijari, J; Noldt, U; Viitanen, H; Vuorinen, M; Kainulainen, P; Holopainen, J K

2004-01-01

We tested how terpenoid (i.e., monoterpenes and resin acids) composition and concentration in wood affects resistance against wood-borers and decaying fungi. Scots pine (Pinus sylvestris) wood from nine provenances having variable terpenoid profiles was studied against the old house borer, Hylotrupes bajulus, and the decay fungus, Coniophora puteana. Provenances represented a 1200-km N-S transect from Estonia to northern Finland, but they were all cultivated for 7 years in the same nursery field, in central Finland. Mean relative growth rate (MRGR) of small H. hajulus larvae positively correlated with the total monoterpene concentration of wood, and feeding was associated with high proportion of levopimaric+palustric acid in wood. Provenance did not affect the MRGR of small or big larvae, but big larvae consumed more wood and produced more frass on the northern Ylitornio trees than on the southern Rakvere and Ruokolahti trees. Low beta-pinene and total monoterpene concentration and low beta: alpha-pinene ratio in wood were all associated with a high number of eggs. The most northern Muonio provenance was the most favored as an oviposition site, differing significantly from Saaremaa, Tenhola, and Suomussalmi. Wood from Saaremaa, Tenhola, Ruokolahti, and Suomussalmi provenance was most resistant against decay fungus, differing significantly from that of Kinnula provenance. However, decay resistance was not clearly associated with the concentrations of wood terpenoids. These results suggest that monoterpene composition of wood affects resistance against wood-boring Cerambycid beetles, but resistance against wood-decaying fungi is not as clearly associated with wood terpenoids.

Fusarium and other opportunistic hyaline fungi

USDA-ARS?s Scientific Manuscript database

This chapter focuses on those fungi that grow in tissue in the form of hyaline or lightly colored septate hyphae. These fungi include Fusarium and other hyaline fungi. Disease caused by hyaline fungi is referred to as hyalohyphomycosis. Hyaline fungi described in this chapter include the anamorphic,...

The use of gas-sensor arrays in the detection of bole and root decays in living trees: development of a new non-invasive method of sampling and analysis

Treesearch

Manuela Baietto; Sofia Aquaro; Dan Wilson; Letizia Pozzi; Danieli Bassi

2015-01-01

Wood rot is a serious fungal disease of trees. Wood decay fungi penetrate and gain entry into trees through pruning cuts or open wounds using extracellular digestive enzymes to attack all components of the cell wall, leading to the destruction of sapwood which compromises wood strength and stability. On living trees, it is often difficult to diagnose wood rot disease,...

21 CFR 529.1030 - Formalin.

Code of Federal Regulations, 2013 CFR

2013-04-01

... when pond is heavily loaded with fish or phytoplankton. (ii) For control of fungi of the... the lower concentration when ponds, tanks, or raceways are heavily loaded with phytoplankton or fish to avoid oxygen depletion due to the biological oxygen demand by decay of dead phytoplankton...

21 CFR 529.1030 - Formalin.

Code of Federal Regulations, 2012 CFR

2012-04-01

... when pond is heavily loaded with fish or phytoplankton. (ii) For control of fungi of the... the lower concentration when ponds, tanks, or raceways are heavily loaded with phytoplankton or fish to avoid oxygen depletion due to the biological oxygen demand by decay of dead phytoplankton...

Diseases

Treesearch

Thomas E. Hinds

1985-01-01

Although many diseases attack aspen, relatively few kill or seriously injure living trees. The common leaf diseases, in general, are widely distributed throughout the range of aspen, whereas there are subtle differences in distribution between the important decay fungi, and apparently entirely different areas of distribution of major cankercausing organisms. However,...

Cellulose-Silica Nanocomposites of High Reinforcing Content with Fungi Decay Resistance by One-Pot Synthesis

PubMed Central

Rodríguez-Robledo, M. Concepción; González-Lozano, M. Azucena; Ponce-Peña, Patricia; Quintana Owen, Patricia; Aguilar-González, Miguel Angel; Nieto-Castañeda, Georgina; López-Martínez, Rubén; Ramírez-Galicia, Guillermo

2018-01-01

Hybrid bionanocomposites based on cellulose matrix, with silica nanoparticles as reinforcers, were prepared by one-pot synthesis of cellulose surface modified by solvent exchange method to keep the biopolymer net void for hosting inorganic nanoparticles. Neither expensive inorganic-particle precursors nor crosslinker agents or catalysts were used for effective dispersion of reinforcer concentration up to 50 wt %. Scanning electron microscopy of the nanocomposites shows homogeneous dispersion of reinforcers in the surface modified cellulose matrix. The FTIR spectra demonstrated the cellulose features even at 50 weight percent content of silica nanoparticles. Such a high content of silica provides high thermal stability to composites, as seen by TGA-DSC. The fungi decay resistance to Trametes versicolor was measured by standard test showing good resistance even with no addition of antifungal agents. This one-pot synthesis of biobased hybrid materials represents an excellent way for industrial production of high performance materials, with a high content of inorganic nanoparticles, for a wide variety of applications. PMID:29642522

Cellulose-Silica Nanocomposites of High Reinforcing Content with Fungi Decay Resistance by One-Pot Synthesis.

PubMed

Rodríguez-Robledo, M Concepción; González-Lozano, M Azucena; Ponce-Peña, Patricia; Quintana Owen, Patricia; Aguilar-González, Miguel Angel; Nieto-Castañeda, Georgina; Bazán-Mora, Elva; López-Martínez, Rubén; Ramírez-Galicia, Guillermo; Poisot, Martha

2018-04-09

Hybrid bionanocomposites based on cellulose matrix, with silica nanoparticles as reinforcers, were prepared by one-pot synthesis of cellulose surface modified by solvent exchange method to keep the biopolymer net void for hosting inorganic nanoparticles. Neither expensive inorganic-particle precursors nor crosslinker agents or catalysts were used for effective dispersion of reinforcer concentration up to 50 wt %. Scanning electron microscopy of the nanocomposites shows homogeneous dispersion of reinforcers in the surface modified cellulose matrix. The FTIR spectra demonstrated the cellulose features even at 50 weight percent content of silica nanoparticles. Such a high content of silica provides high thermal stability to composites, as seen by TGA-DSC. The fungi decay resistance to Trametes versicolor was measured by standard test showing good resistance even with no addition of antifungal agents. This one-pot synthesis of biobased hybrid materials represents an excellent way for industrial production of high performance materials, with a high content of inorganic nanoparticles, for a wide variety of applications.

Threesomes destabilise certain relationships: multispecies interactions between wood decay fungi in natural resources

PubMed Central

Savoury, Melanie; Toledo, Selin; Kingscott-Edmunds, James; Bettridge, Aimee; Waili, Nasra Al; Boddy, Lynne

2017-01-01

Abstract Understanding interspecific interactions is key to explaining and modelling community development and associated ecosystem function. Most interactions research has focused on pairwise combinations, overlooking the complexity of multispecies communities. This study investigated three-way interactions between saprotrophic fungi in wood and across soil, and indicated that pairwise combinations are often inaccurate predictors of the outcomes of multispecies competition in wood block interactions. This inconsistency was especially true of intransitive combinations, resulting in increased species coexistence within the resource. Furthermore, the addition of a third competitor frequently destabilised the otherwise consistent outcomes of pairwise combinations in wood blocks, which occasionally resulted in altered resource decomposition rates, depending on the relative decay abilities of the species involved. Conversely, interaction outcomes in soil microcosms were unaffected by the presence of a third combatant. Multispecies interactions promoted species diversity within natural resources, and made community dynamics less consistent than could be predicted from pairwise interaction studies. PMID:28175239

The importance of associations with saprotrophic non-Rhizoctonia fungi among fully mycoheterotrophic orchids is currently under-estimated: novel evidence from sub-tropical Asia.

PubMed

Lee, Yung-I; Yang, Chih-Kai; Gebauer, Gerhard

2015-09-01

Most fully mycoheterotrophic (MH) orchids investigated to date are mycorrhizal with fungi that simultaneously form ectomycorrhizas with forest trees. Only a few MH orchids are currently known to be mycorrhizal with saprotrophic, mostly wood-decomposing, fungi instead of ectomycorrhizal fungi. This study provides evidence that the importance of associations between MH orchids and saprotrophic non-Rhizoctonia fungi is currently under-estimated. Using microscopic techniques and molecular approaches, mycorrhizal fungi were localized and identified for seven MH orchid species from four genera and two subfamilies, Vanilloideae and Epidendroideae, growing in four humid and warm sub-tropical forests in Taiwan. Carbon and nitrogen stable isotope natural abundances of MH orchids and autotrophic reference plants were used in order to elucidate the nutritional resources utilized by the orchids. Six out of the seven MH orchid species were mycorrhizal with either wood- or litter-decaying saprotrophic fungi. Only one orchid species was associated with ectomycorrhizal fungi. Stable isotope abundance patterns showed significant distinctions between orchids mycorrhizal with the three groups of fungal hosts. Mycoheterotrophic orchids utilizing saprotrophic non-Rhizoctonia fungi as a carbon and nutrient source are clearly more frequent than hitherto assumed. On the basis of this kind of nutrition, orchids can thrive in deeply shaded, light-limiting forest understoreys even without support from ectomycorrhizal fungi. Sub-tropical East Asia appears to be a hotspot for orchids mycorrhizal with saprotrophic non-Rhizoctonia fungi. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Mineralisation of 14C-labelled synthetic lignin and ligninolytic enzyme activities of litter-decomposing basidiomycetous fungi.

PubMed

Steffen, K T; Hofrichter, M; Hatakka, A

2000-12-01

Within a screening program, 27 soil litter-decomposing basidiomycetes were tested for ligninolytic enzyme activities using agar-media containing 2,2'-azinobis(3-ethylbenzthiazoline-6-sulphonate), a humic acid or Mn2+ ions as indicator substrates. Most active species were found within the family Strophariaceae (Agrocybe praecox, Stropharia coronilla, S. rugosoannulata) and used for mineralisation experiments with a 14C-ring-labelled synthetic lignin (14C-DHP). The fungi mineralised around 25% of the lignin to 14CO2 within 12 weeks of incubation in a straw environment; about 20% of the lignin was converted to water-soluble fragments. Mn-peroxidase was found to be the predominant ligninolytic enzyme of all three fungi in liquid culture and its production was strongly enhanced in the presence of Mn2+ ions. The results of this study demonstrate that certain ubiquitous litter-decomposing basidiomycetes possess ligninolytic activities similar to the wood-decaying white-rot fungi, the most efficient lignin degraders in nature.

Bacterial Community Succession in Pine-Wood Decomposition.

PubMed

Kielak, Anna M; Scheublin, Tanja R; Mendes, Lucas W; van Veen, Johannes A; Kuramae, Eiko E

2016-01-01

Though bacteria and fungi are common inhabitants of decaying wood, little is known about the relationship between bacterial and fungal community dynamics during natural wood decay. Based on previous studies involving inoculated wood blocks, strong fungal selection on bacteria abundance and community composition was expected to occur during natural wood decay. Here, we focused on bacterial and fungal community compositions in pine wood samples collected from dead trees in different stages of decomposition. We showed that bacterial communities undergo less drastic changes than fungal communities during wood decay. Furthermore, we found that bacterial community assembly was a stochastic process at initial stage of wood decay and became more deterministic in later stages, likely due to environmental factors. Moreover, composition of bacterial communities did not respond to the changes in the major fungal species present in the wood but rather to the stage of decay reflected by the wood density. We concluded that the shifts in the bacterial communities were a result of the changes in wood properties during decomposition and largely independent of the composition of the wood-decaying fungal communities.

Bacterial Community Succession in Pine-Wood Decomposition

PubMed Central

Kielak, Anna M.; Scheublin, Tanja R.; Mendes, Lucas W.; van Veen, Johannes A.; Kuramae, Eiko E.

2016-01-01

Though bacteria and fungi are common inhabitants of decaying wood, little is known about the relationship between bacterial and fungal community dynamics during natural wood decay. Based on previous studies involving inoculated wood blocks, strong fungal selection on bacteria abundance and community composition was expected to occur during natural wood decay. Here, we focused on bacterial and fungal community compositions in pine wood samples collected from dead trees in different stages of decomposition. We showed that bacterial communities undergo less drastic changes than fungal communities during wood decay. Furthermore, we found that bacterial community assembly was a stochastic process at initial stage of wood decay and became more deterministic in later stages, likely due to environmental factors. Moreover, composition of bacterial communities did not respond to the changes in the major fungal species present in the wood but rather to the stage of decay reflected by the wood density. We concluded that the shifts in the bacterial communities were a result of the changes in wood properties during decomposition and largely independent of the composition of the wood-decaying fungal communities. PMID:26973611

Phylogeny and taxonomic revision of Thelonectria discophora (Ascomycota, Hypocreales, Nectriaceae) species complex

USDA-ARS?s Scientific Manuscript database

Thelonectria discophora (Thelonectria, Nectriaceae, Hypocreales) is a conspicuous group of saprobic fungi on decaying plant material, characterized by red perithecia each with a broad mammiform (nipple-like) apex. The anamorphic state is characterized by a cylindrocarpon-like morphology, with 3–5 se...

Oxidative cleavage of diverse ethers by an extracellular fungal peroxygenase

Treesearch

Matthias Kinne; Marzena Poraj-Kobielska; Sally A. Ralph; Rene Ullrich; Martin Hofrichter; Kenneth E. Hammel

2009-01-01

Many litter-decay fungi secrete heme-thiolate peroxygenases that oxidize various organic chemicals, but little is known about the role or mechanism of these enzymes. We found that the extracellular peroxygenase of Agrocybe aegerita catalyzed the H2O2-dependent cleavage of environmentally significant...

Comparative genomics of Ceriporiopsis subvermispora and Phanerochaete chrysosporium provide insight into selective ligninolysis

Treesearch

Elena Fernandez-Fueyo; Francisco J. Ruiz-Dueñas; Patricia Ferreira; Dimitrios Floudas; David S. Hibbett; Paulo Canessa; Luis F. Larrondo; Tim Y. James; Daniela Seelenfreund; Sergio Lobos; Rubén Polanco; Mario Tello; Yoichi Honda; Takahito Watanabe; Takashi Watanabe; Jae San Ryu; Christian P. Kubicek; Monika Schmoll; Jill Gaskell; Kenneth E. Hammel; Franz J. St. John; Amber Vanden Wymelenberg; Grzegorz Sabat; Sandra Splinter BonDurant; Khajamohiddin Syed; Jagjit S. Yadav; Harshavardhan Dodapaneni; Venkataramanan Subramanian; José L. Lavin; José A. Oguiza; Gumer Perez; Antonio G. Pisabarro; Lucia Ramirez; Francisco Santoyo; Emma Master; Pedro M. Coutinho; Bernard Henrissat; Vincent Lombard; Jon Karl Magnuson; Ursula Kües; Chiaki Hori; Kiyohiko Igarashi; Masahiro Samejima; Benjamin W. Held; Kerrie W. Barry; Kurt M. LaButti; Alla Lapidus; Erika A. Lindquist; Susan M. Lucas; Robert Riley; Asaf A. Salamov; Dirk Hoffmeister; Daniel Schwenk; Yitzhak Hadar; Oded Yarden; Ronald P. de Vries; Ad Wiebenga; Jan Stenlid; Daniel Eastwood; Igor V. Grigoriev; Randy M. Berka; Robert A. Blanchette; Phil Kersten; Angel T. Martinez; Rafael Vicuna; Daniel Cullen

2012-01-01

Efficient lignin depolymerization is unique to the wood decay basidiomycetes, collectively referred to as white rot fungi. Phanerochaete chrysosporium simultaneously degrades lignin and cellulose, whereas the closely related species, Ceriporiopsis subvermispora, also depolymerizes lignin but may do so with relatively little...

Ectomycorrhizal fungi decompose soil organic matter using oxidative mechanisms adapted from saprotrophic ancestors.

PubMed

Shah, Firoz; Nicolás, César; Bentzer, Johan; Ellström, Magnus; Smits, Mark; Rineau, Francois; Canbäck, Björn; Floudas, Dimitrios; Carleer, Robert; Lackner, Gerald; Braesel, Jana; Hoffmeister, Dirk; Henrissat, Bernard; Ahrén, Dag; Johansson, Tomas; Hibbett, David S; Martin, Francis; Persson, Per; Tunlid, Anders

2016-03-01

Ectomycorrhizal fungi are thought to have a key role in mobilizing organic nitrogen that is trapped in soil organic matter (SOM). However, the extent to which ectomycorrhizal fungi decompose SOM and the mechanism by which they do so remain unclear, considering that they have lost many genes encoding lignocellulose-degrading enzymes that are present in their saprotrophic ancestors. Spectroscopic analyses and transcriptome profiling were used to examine the mechanisms by which five species of ectomycorrhizal fungi, representing at least four origins of symbiosis, decompose SOM extracted from forest soils. In the presence of glucose and when acquiring nitrogen, all species converted the organic matter in the SOM extract using oxidative mechanisms. The transcriptome expressed during oxidative decomposition has diverged over evolutionary time. Each species expressed a different set of transcripts encoding proteins associated with oxidation of lignocellulose by saprotrophic fungi. The decomposition 'toolbox' has diverged through differences in the regulation of orthologous genes, the formation of new genes by gene duplications, and the recruitment of genes from diverse but functionally similar enzyme families. The capacity to oxidize SOM appears to be common among ectomycorrhizal fungi. We propose that the ancestral decay mechanisms used primarily to obtain carbon have been adapted in symbiosis to scavenge nutrients instead. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Pyranose Oxidase, a Major Source of H(2)O(2) during Wood Degradation by Phanerochaete chrysosporium, Trametes versicolor, and Oudemansiella mucida.

PubMed

Daniel, G; Volc, J; Kubatova, E

1994-07-01

The production of the H(2)O(2)-generating enzyme pyranose oxidase (POD) (EC 1.1.3.10) (synonym, glucose 2-oxidase), two ligninolytic peroxidases, and laccase in wood decayed by three white rot fungi was investigated by correlated biochemical, immunological, and transmission electron microscopic techniques. Enzyme activities were assayed in extracts from decayed birch wood blocks obtained by a novel extraction procedure. With the coupled peroxidase-chromogen (3-dimethylaminobenzoic acid plus 3-methyl-2-benzothiazolinone hydrazone hydrochloride) spectrophotometric assay, the highest POD activities were detected in wood blocks degraded for 4 months and were for Phanerochaete chrysosporium (149 mU g [dry weight] of decayed wood), Trametes versicolor (45 mU g), and Oudemansiella mucida (1.2 mU g), corresponding to wood dry weight losses of 74, 58, and 13%, respectively. Mn-dependent peroxidase activities in the same extracts were comparable to those of POD, while lignin peroxidase activity was below the detection limit for all fungi with the veratryl alcohol assay. Laccase activity was high with T. versicolor (422 mU g after 4 months), in trace levels with O. mucida, and undetectable in P. chrysosporium extracts. Evidence for C-2 specificity of POD was shown by thin-layer chromatography detection of 2-keto-d-glucose as the reaction product. By transmission electron microscopy-immunocytochemistry, POD was found to be preferentially localized in the hyphal periplasmic space of P. chrysosporium and O. mucida and associated with membranous materials in hyphae growing within the cell lumina or cell walls of partially and highly degraded birch fibers. An extracellular distribution of POD associated with slime coating wood cell walls was also noted. The periplasmic distribution in hyphae and extracellular location of POD are consistent with the reported ultrastructural distribution of H(2)O(2)-dependent Mn-dependent peroxidases. This fact and the dominant presence of POD and Mn-dependent peroxidase in extracts from degraded wood suggest a cooperative role of the two enzymes during white rot decay by the test fungi.

Prospects for bioprocess development based on recent genome advances in lignocellulose degrading basidiomycetes

Treesearch

Chiaki Hori; Daniel Cullen

2016-01-01

Efficient and complete degradation of woody plant cell walls requires the concerted action of hydrolytic and oxidative systems possessed by a relatively small group of filamentous basidiomycetous fungi. Among these wood decay species, Phanerochaete chrysosporium was the first to be sequenced (Martinez et al. 2004). In...

Wood preservation

Treesearch

Stan T. Lebow

2010-01-01

Many commonly used wood species can deteriorate if exposed to conditions that support growth of wood-degrading organisms (see Chap. 14). Wood products can be protected from the attack of decay fungi, harmful insects, or marine borers by applying chemical preservatives. Preservative treatments greatly increase the life of wood structures, thus reducing replacement costs...

Biological properties

Treesearch

Rebecca E. Ibach

2005-01-01

There are numerous biological degradations that wood is exposed to in various environments. Biological damage occurs when a log, sawn product, or final product is not stored, handled, or designed properly. Biological organisms, such as bacteria, mold, stain, decay fungi, insects, and marine borers, depend heavily on temperature and moisture conditions to grow. A higher...

Forest pathology and entomology at Fort Valley Experimental Forest

Treesearch

Brian W. Geils

2008-01-01

Forest pathology and entomology have been researched at Fort Valley Experimental Forest throughout its history. The pathogens and insects of particular interest are mistletoes, decay and canker fungi, rusts, bark beetles, and various defoliators. Studies on life history, biotic interactions, impacts, and control have been published and incorporated into silvicultural...

Localizing gene regulation reveals a staggered wood decay mechanism for the brown rot fungus Postia placenta

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Jiwei; Presley, Gerald N.; Hammel, Kenneth E.

The fungi that cause brown rot of wood are essential contributors to biomass recycling in forest ecosystems. Their highly efficient cellulolytic systems, which may have practical applications, apparently depend on a combination of two mechanisms: nonselective oxidation of the lignocellulose by reactive oxygen species (ROS) coupled with hydrolysis of the polysaccharide components by a limited set of glycoside hydrolases (GHs). Since the production of strongly oxidizing ROS appears incompatible with the operation of GHs, it has been proposed that the fungi regulate ROS production by maintaining concentration gradients of the chelated metal ions they use to generate extracellular oxidants. However,more » calculations have indicated that this protective mechanism is physically infeasible. We examined a different hypothesis, that expression of ROS and GH components is temporally staggered by brown rot fungi in wood. We sectioned thin wafers of spruce and aspen that had been colonized directionally by Postia placenta and measured expression of relevant genes and some of the encoded enzymes, thus using the spatial distribution of fungal hyphae to resolve a fine-scale temporal sequence. Hierarchical clustering of gene expression for eight oxidoreductases thought to have a role in ROS production and of eight GHs revealed a zone of oxidoreductase upregulation at the hyphal front that persisted about 48 h before upregulation of the GHs. Additional evidence for differential expression was provided by localization of endoglucanase, xylanase, mannanase, and laccase activities in the colonized wood. Our results support a two-step mechanism for brown rot, in which substrate oxidation precedes enzymatic hydrolysis.« less

Localizing gene regulation reveals a staggered wood decay mechanism for the brown rot fungus Postia placenta

DOE PAGES

Zhang, Jiwei; Presley, Gerald N.; Hammel, Kenneth E.; ...

2016-09-12

The fungi that cause brown rot of wood are essential contributors to biomass recycling in forest ecosystems. Their highly efficient cellulolytic systems, which may have practical applications, apparently depend on a combination of two mechanisms: nonselective oxidation of the lignocellulose by reactive oxygen species (ROS) coupled with hydrolysis of the polysaccharide components by a limited set of glycoside hydrolases (GHs). Since the production of strongly oxidizing ROS appears incompatible with the operation of GHs, it has been proposed that the fungi regulate ROS production by maintaining concentration gradients of the chelated metal ions they use to generate extracellular oxidants. However,more » calculations have indicated that this protective mechanism is physically infeasible. We examined a different hypothesis, that expression of ROS and GH components is temporally staggered by brown rot fungi in wood. We sectioned thin wafers of spruce and aspen that had been colonized directionally by Postia placenta and measured expression of relevant genes and some of the encoded enzymes, thus using the spatial distribution of fungal hyphae to resolve a fine-scale temporal sequence. Hierarchical clustering of gene expression for eight oxidoreductases thought to have a role in ROS production and of eight GHs revealed a zone of oxidoreductase upregulation at the hyphal front that persisted about 48 h before upregulation of the GHs. Additional evidence for differential expression was provided by localization of endoglucanase, xylanase, mannanase, and laccase activities in the colonized wood. Our results support a two-step mechanism for brown rot, in which substrate oxidation precedes enzymatic hydrolysis.« less

Multiple rare opportunistic and pathogenic fungi in persistent foot skin infection.

PubMed

Chan, Giek Far; Sinniah, Sivaranjini; Idris, Tengku Idzzan Nadzirah Tengku; Puad, Mohamad Safwan Ahmad; Abd Rahman, Ahmad Zuhairi

2013-03-01

Persistent superficial skin infection caused by multiple fungi is rarely reported. Recently, a number of fungi, both opportunistic and persistent in nature were isolated from the foot skin of a 24-year old male in Malaysia. The fungi were identified as Candida parapsilosis, Rhodotorula mucilaginosa, Phoma spp., Debaryomyces hansenii, Acremonium spp., Aureobasidium pullulans and Aspergillus spp., This is the first report on these opportunistic strains were co-isolated from a healthy individual who suffered from persistent foot skin infection which was diagnosed as athlete's foot for more than 12 years. Among the isolated fungi, C. parapsilosis has been an increasingly common cause of skin infections. R. mucilaginosa and D. hansenii were rarely reported in cases of skin infection. A. pullulans, an emerging fungal pathogen was also being isolated in this case. Interestingly, it was noted that C. parapsilosis, R. mucilaginosa, D. hansenii and A. pullulans are among the common halophiles and this suggests the association of halotolerant fungi in causing persistent superficial skin infection. This discovery will shed light on future research to explore on effective treatment for inhibition of pathogenic halophiles as well as to understand the interaction of multiple fungi in the progress of skin infection.

Identification and characterization of Pestalotiopsis-like fungi related to grapevine diseases in China.

PubMed

Jayawardena, Ruvishika S; Zhang, Wei; Liu, Mei; Maharachchikumbura, Sajeewa S N; Zhou, Ying; Huang, JinBao; Nilthong, Somrudee; Wang, ZhongYue; Li, XingHong; Yan, JiYe; Hyde, Kevin D

2015-05-01

Pestalotiopsis-like fungi are an important plant pathogenic genus causing postharvest fruit rot and trunk diseases in grapevine in many countries. Pestalotiopsis-like fungi diseases were studied in vineyards in nine provinces across China. Multi-gene (ITS, β-tubulin and tef1) analysis coupled with morphology showed that a Neopestalotiopsis sp. and Pestalotiopsis trachicarpicola are associated in causing grapevine fruit rot and trunk diseases in China. Pestalotiopsis trachicarpicola is reported as the causative agent of grapevine diseases in the world for the first time. Neopestalotiopsis sp. caused significantly longer lesions than the other taxon present. This study represents the first attempt to identify and characterize the Pestalotiopsis-like fungi causing grapevine diseases in China using both morphological and molecular approaches. Copyright © 2014 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Gene expression analysis of copper tolerance and wood decay in the brown rot fungus Fibroporia radiculosa

USDA-ARS?s Scientific Manuscript database

Many brown rot fungi are capable of rapidly degrading wood and are copper-tolerant. To better understand the genes that control these processes, we examined gene expression of Fibroporia radiculosa growing on wood treated with a copper-based preservative that combined copper carbonate with dimethyld...

Unique preservative tolerance in Tyromyces palustris

Treesearch

Frederick Green; Rachel A. Arango; Carol A. Clausen

2005-01-01

Fungal tolerance to wood preservatives has been critically important for many years. The tolerance of type cultures to common wood preservatives is, in fact, noted in the AWPA Standards [1]. Gloeophyllum trabeum Mad-617, for example, is particularly tolerant to phenolic and arsenic compounds. One important group of decay fungi that has been studied extensively are...

Chapter 5:Biological Properties of Wood

Treesearch

Rebecca E. Ibach

2013-01-01

There are numerous biological degradations that wood is exposed to in various environments. Biological damage occurs when a log, sawn product, or final product is not stored, handled, or designed properly. Biological organisms such as bacteria, mold, stain, decay fungi, insects, and marine borers depend heavily on temperature and moisture conditions to grow. Figure 5.1...

Bioremediation and degradation of CCA-treated wood waste.

Treesearch

Barbara L Illman; Vina W. Yang

2004-01-01

Bioprocessing CCA wood waste is an efficient and economical alternative to depositing the waste in landfills, especially if landfill restrictions on CCA waste are imposed nation wide. We have developed bioremediation and degradation technologies for microbial processing of CCA waste. The technologies are based on specially formulated inoculum of wood decay fungi,...

Co-culturing Effects of Coexisting Bacteria on Wood Degradation by Trametes versicolor.

PubMed

Kamei, Ichiro

2017-01-01

White-rot fungi are the main decomposers of wood cell-wall polymer in forest ecosystems. Little is known, however, about the interactions between white-rot fungi and other coexisting microorganisms in decayed wood. A white-rot fungus, Trametes versicolor strain TN6F, was isolated from a fruit body, and 44 strains of coexisting cultivable bacteria were isolated from its substrate, natural white rot-decayed wood. The effects of these bacteria on fungal growth were examined by an in vitro confrontation growth assay. Among the isolates, nine bacterial strains inhibited the growth of strain TN6F, while 35 strains did not affect the growth of TN6F. However, when co-cultured with strain TN6F on wood powder, many bacterial strains promoted the weight loss of the substrate. A subsequent chemical composition analysis showed that co-culturing accelerated delignification. Higher laccase activity was detected when strain TN6F was co-cultured on wood powder medium with bacterial strains TN6W-26 or TN6W-27. These results indicate that some bacterial strains might promote wood degradation.

The Ecological Genomics of Fungi: Repeated Elements in Filamentous Fungi with a Focus on Wood-Decay Fungi

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murat, Claude; Payen, Thibaut; Petitpierre, Denis

2013-01-01

In the last decade, the genome of several dozen filamentous fungi have been sequenced. Interestingly, vast diversity in genome size was observed (Fig. 2.1) with 14-fold differences between the 9 Mb of the human pathogenic dandruff fungus (Malassezia globosa; Xu, Saunders, et al., 2007) and the 125 Mb of the ectomycorrhizal black truffle of P rigord (Tuber melanosporum; Martin, Kohler, et al., 2010). Recently, Raffaele and Kamoun (2012) highlighted that the genomes of several lineages of filamentous plant pathogens have been shaped by repeat-driven expansion. Indeed, repeated elements are ubiquitous in all prokaryote and eukaryote genomes; however, their frequencies canmore » vary from just a minor percentage of the genome to more that 60 percent of the genome. Repeated elements can be classified in two major types: satellites DNA and transposable elements. In this chapter, the different types of repeated elements and how these elements can impact genome and gene repertoire will be described. Also, an intriguing link between the transposable elements richness and diversity and the ecological niche will be highlighted.« less

Characterizing forest root‐ and butt‐rot fungi in Yap, Palau, Pohnpei, Kosrae, Guam and Saipan [Chapter III

Treesearch

Phil Cannon; Ned B. Klopfenstein; Mee-Sook Kim; Yuko Ota; Norio Sahashi; Robert L. Schlub; Roger Brown; Sara M. Ashiglar; Amy L. Ross-Davis; John W. Hanna

2014-01-01

Ganoderma and Phellinus are two common fungal genera causing butt-rot on trees growing on USA-affiliated islands of the western Pacific. Although these fungi can be quite prevalent, especially in some older mangrove stands, it appears that the majority of infections caused by these fungi leads to severe rotting of the heartwood but do not kill the living...

Scytalidium dimidiatum and Lecythophora hoffmannii: unusual causes of fungal infections in a patient with AIDS.

PubMed Central

Marriott, D J; Wong, K H; Aznar, E; Harkness, J L; Cooper, D A; Muir, D

1997-01-01

Immunocompromised patients are susceptible to infections by fungi that seldom cause disease in humans. We describe a human immunodeficiency virus-infected patient who had simultaneous infections with two fungi which are rare causes of serious infection: Lecythophora hoffmannii, causing chronic sinusitis, and Scytalidium dimidiatum, causing skin lesions, lymphangitis, and lymphadenitis. The clinical and pathologic findings are discussed. PMID:9350765

[Hazardous food-borne fungi and present and future approaches to the mycotoxin regulations in Japan].

PubMed

Takatori, Kosuke; Aihara, Maki; Sugita-Konishi, Yoshiko

2006-01-01

In recent years, various food-related accidents and health scares have dissipated trust in the food industry. Health hazards resulting from food contaminated with fungi is increasing. Food contamination by fungi causes many problems, especially in Japan, which relies on foreign countries for about 60% of its food: the contamination of imported food by fungi and mycotoxins constitutes a serious problem. As the quantity of imported food increases and changes in food distribution have occurred, so too has the number and type of fungi causing food-related damages; osmophilic and thermotolerant fungi, in addition to the mainstream fungi of genera Cladosporium, Pecinillium, and Aspergillus, have become a problem. Although European countries and the U.S. have recently conducted risk assessments for mycotoxins, Japan has not attained an international level in the determination of baseline values. However, in addition to risk management for Aflatoxin M1, Ochratoxin, T-2 toxin/HT-2 toxin, and Fumonisin, determination of baseline values for mycotoxins is beginning in Japan. In this review, we summarize hazardous food-borne fungi, and present and future approaches to the mycotoxin regulations in Japan.

Isolation, Identification And Screening Antibacterial Activity from Marine Sponge-Associated Fungi Against Multidrug-Resistant (MDR) Escherichia coli

NASA Astrophysics Data System (ADS)

Triandala Sibero, Mada; Sabdaningsih, Aninditia; Cristianawati, Olvi; Nuryadi, Handung; Karna Radjasa, Ocky; Sabdono, Agus; Trianto, Agus

2017-02-01

Irrational used of antibiotic in several decades ago causing resistant in bacteria and decreasing the cure rate of infectious diseases. Multidrug-resistant (MDR) Escherichia coli is known to cause various of infectious diseases such as urinary tract infection, nosocomial bloodstream infection, meningitis, bacteraemia, and gastrointestinal disease. Marine sponge-associated fungi have potential as source of new compound to combat MDR E. coli. The aims of this research were to isolate marine sponge-assosiated fungi, to screen potential fungi against MDR E. coli, to identify the potential fungi and its host sponge. There were 29 marine sponge-associated fungi successfully isolated from 9 sponges. Among 29 sponge-associated fungi screened, there were 7 isolates showed antibacterial activity against MDR E. coli. The best inhibition zone produced by MPS 14.1/MT 02 and MPS 14.3/MT 04 from sponge PP.SP.16.14. According to fungi identification result fungus MPS 14.1/MT 02 was identified as Trichoderma asperellum while MPS 14.3/MT 04 was identified as Trichoderma reesei. Sponge identification leaded the PP.SP.16.14 as Cinachyrella sp.

Microscopic, chemical, and molecular-biological investigation of the decayed medieval stained window glasses of two Catalonian churches

PubMed Central

Piñar, Guadalupe; Garcia-Valles, Maite; Gimeno-Torrente, Domingo; Fernandez-Turiel, Jose Luis; Ettenauer, Jörg; Sterflinger, Katja

2013-01-01

We investigated the decayed historical church window glasses of two Catalonian churches, both under Mediterranean climate. Glass surfaces were studied by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and X-ray diffraction (XRD). Their chemical composition was determined by wavelength-dispersive spectrometry (WDS) microprobe analysis. The biodiversity was investigated by molecular methods: DNA extraction from glass, amplification by PCR targeting the16S rRNA and ITS regions, and fingerprint analyses by denaturing gradient gel electrophoresis (DGGE). Clone libraries containing either PCR fragments of the bacterial 16S rDNA or the fungal ITS regions were screened by DGGE. Clone inserts were sequenced and compared with the EMBL database. Similarity values ranged from 89 to 100% to known bacteria and fungi. Biological activity in both sites was evidenced in the form of orange patinas, bio-pitting, and mineral precipitation. Analyses revealed complex bacterial communities consisting of members of the phyla Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria. Fungi showed less diversity than bacteria, and species of the genera Cladosporium and Phoma were dominant. The detected Actinobacteria and fungi may be responsible for the observed bio-pitting phenomenon. Moreover, some of the detected bacteria are known for their mineral precipitation capabilities. Sequence results also showed similarities with bacteria commonly found on deteriorated stone monuments, supporting the idea that medieval stained glass biodeterioration in the Mediterranean area shows a pattern comparable to that on stone. PMID:24092957

In vitro suppression of fungi caused by combinations of apparently non-antagonistic soil bacteria.

PubMed

de Boer, Wietse; Wagenaar, Anne-Marieke; Klein Gunnewiek, Paulien J A; van Veen, Johannes A

2007-01-01

We hypothesized that apparently non-antagonistic soil bacteria may contribute to suppression of fungi during competitive interactions with other bacteria. Four soil bacteria (Brevundimonas sp., Luteibacter sp., Pedobacter sp. and Pseudomonas sp.) that exhibited little or no visible antifungal activity on different agar media were prescribed. Single and mixed strains of these species were tested for antagonism on a nutrient-poor agar medium against the plant pathogenic fungi Fusarium culmorum and Rhizoctonia solani and the saprotrophic fungus Trichoderma harzianum. Single bacterial strains caused little to moderate growth reduction of fungi (quantified as ergosterol), most probably due to nutrient withdrawal from the media. Growth reduction of fungi by the bacterial mixture was much stronger than that by the single strains. This appeared to be mostly due to competitive interactions between the Pseudomonas and Pedobacter strains. We argue that cohabitation of these strains triggered antibiotic production via interspecific interactions and that the growth reduction of fungi was a side-effect caused by the sensitivity of the fungi to bacterial secondary metabolites. Induction of gliding behavior in the Pedobacter strain by other strains was also observed. Our results indicate that apparently non-antagonistic soil bacteria may be important contributors to soil suppressiveness and fungistasis when in a community context.

Effects of photochemical oxidant injury of ponderosa and Jeffrey pines on susceptibility of sapwood and freshly cut stumps to Fomes annosus. [Pinus ponderosa; Pinus jeffreyi; Fomes annosus; Trichoderma spp. ; Polyporus versicolor; Poria Monticola

DOE Office of Scientific and Technical Information (OSTI.GOV)

James, R.L.; Cobb, F.W. Jr.; Wilcox, W.W.

1980-01-01

Ponderosa and Jeffrey pine sapwood samples and freshly cut stumps from trees with different amounts of oxidant injury were inoculated with Fomes annosus. With stumps, percentage of surface cross-section area infected and extent of vertical colonization were determined 1 mo and 6-10 mo after inoculation, respectively. Increase in surface area infection with increased oxidant injury, expressed as upper-crown needle retention, was statistically significant for ponderosa pine (P=0.01), but was not for Jeffrey pine. Also, the rate of vertical colonization was greater in stumps from severely oxidant-injured trees than in those from slightly injured trees. The relationship between injury and colonizationmore » was significant for Jeffrey pine (P = 0.05) and for ponderosa pine at one site (P = 0.03), but nonsignificant (P = 0.18) for ponderosa pine at a second site. Increased susceptibility of stumps to F. annosus appeared to be associated with decreased colonization by other fungi (especially Trichoderma spp. and blue stain fungi). Laboratory tests indicated that decay susceptibility of excised sapwood to F. annosus apparently was not affected by oxidant injury with Jeffrey pine, but weight loss of ponderosa pine sapwood was correlated with decreased injury (greater needle retention). On the other hand, weight losses of Jeffrey pine caused by Polyporus versicolor and of ponderosa pine caused by Poria monticola were correlated with increased injury (increased needle chlorosis). 27 references, 2 figures, 3 tables.« less

Synchrotron-based X-ray fluorescence microscopy enables multiscale spatial visualization of ions involved in fungal lignocellulose deconstruction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kirker, Grant; Zelinka, Sam; Gleber, Sophie -Charlotte

Ions play an important role in the growth and development of filamentous fungi, particularly in the fungal decay process of lignocellulose materials. The role of ions in wood degradation, and more broadly fungal metabolism, have implications for diverse research disciplines ranging from plant pathology and forest ecology, to wood protection. Despite the importance of ions in both enzymatic and non-enzymatic fungal decay mechanisms, the spatial distribution of ions in wood and fungal hyphae during decay is not known. Here we employ synchrotron based X-ray fluorescence microscopy (XFM) to map physiologically relevant ions, such as K, Ca, Mn, Fe, and Zn,more » in wood being decayed by the model brown rot fungus Serpula lacrymans. Two-dimensional XFM maps were obtained to study the ion spatial distributions from mm to submicron length scales in wood and hyphae. Three-dimensional ion volume reconstructions with submicron spatial resolution were also acquired of wood cell walls and fungal hyphae, and an estimation of oxalate concentration at the microscale was made. Results show that the fungus actively transports some ions, such as Fe, into the wood and controls the distribution of ions at both the bulk wood and cellular length scales. Within the fungal hyphae, ion volume reconstructions show inhomogeneous ion distributions at the micron length scale and this localization may be indicative of both physiological status and requirements or in some cases, potentially sites associated with the initiation of metal-catalyzed wood degradation. Finally, these measurements illustrate how synchrotron based XFM is uniquely qualified for probing the role of ions in the growth and metabolic processes of filamentous fungi.« less

Synchrotron-based X-ray fluorescence microscopy enables multiscale spatial visualization of ions involved in fungal lignocellulose deconstruction

DOE PAGES

Kirker, Grant; Zelinka, Sam; Gleber, Sophie -Charlotte; ...

2017-01-31

Ions play an important role in the growth and development of filamentous fungi, particularly in the fungal decay process of lignocellulose materials. The role of ions in wood degradation, and more broadly fungal metabolism, have implications for diverse research disciplines ranging from plant pathology and forest ecology, to wood protection. Despite the importance of ions in both enzymatic and non-enzymatic fungal decay mechanisms, the spatial distribution of ions in wood and fungal hyphae during decay is not known. Here we employ synchrotron based X-ray fluorescence microscopy (XFM) to map physiologically relevant ions, such as K, Ca, Mn, Fe, and Zn,more » in wood being decayed by the model brown rot fungus Serpula lacrymans. Two-dimensional XFM maps were obtained to study the ion spatial distributions from mm to submicron length scales in wood and hyphae. Three-dimensional ion volume reconstructions with submicron spatial resolution were also acquired of wood cell walls and fungal hyphae, and an estimation of oxalate concentration at the microscale was made. Results show that the fungus actively transports some ions, such as Fe, into the wood and controls the distribution of ions at both the bulk wood and cellular length scales. Within the fungal hyphae, ion volume reconstructions show inhomogeneous ion distributions at the micron length scale and this localization may be indicative of both physiological status and requirements or in some cases, potentially sites associated with the initiation of metal-catalyzed wood degradation. Finally, these measurements illustrate how synchrotron based XFM is uniquely qualified for probing the role of ions in the growth and metabolic processes of filamentous fungi.« less

Laboratory evaluations of woods from Pakistan and their extractives against Postia placenta and Trametes versicolor

Treesearch

Mark Mankowski; Barbar Hassan; Amy Blodgett; Grant T. Kirker

2016-01-01

Natural durable wood species are those which exhibit innate tolerance to wood decay organisms such as fungi and termites. The goal of this study was to evaluate 4 wood species (Dalbergia sissoo, Cedrus deodara, Morus alba and Pinus roxburghii) from Pakistan in order to determine their resistance to both a model brown (

Preservative treatment of wood for farm use

Treesearch

J. Oscar Blew

1965-01-01

With all the favorable properties that contribute to its wide use in farming, wood nevertheless needs to be used intelligently, and protected from certain natural enemies. For example, while some species of wood are naturally resistant to attack by decay fungi and harmful insects, most species lack adequate resistance when exposed to attack, This is not serious when...

Localizing gene regulation reveals a staggered wood decay mechanism for the brown rot fungus Postia placenta

Treesearch

Jiwei Zhang; Gerald N. Presley; Kenneth E. Hammel; Jae-San Ryu; Jon R. Menke; Melania Figueroa; Dehong Hu; Galya Orr; Jonathan S. Schilling

2016-01-01

Wood-degrading brown rot fungi are essential recyclers of plant biomass in forest ecosystems. Their efficient cellulolytic systems, which have potential biotechnological applications, apparently depend on a combination of two mechanisms: lignocellulose oxidation (LOX) by reactive oxygen species (ROS) and polysaccharide hydrolysis by a limited set of glycoside...

Chlorination of lignin by ubiquitous fungi has a likely role in global organochlorine production

Treesearch

Patricia Ortiz-Bermudez; Kolby C. Hirth; Ewald Srebotnik; Kenneth E. Hammel

2007-01-01

Soils and decayed plant litter contain significant quantities of chlorinated aromatic polymers that have a natural but largely unknown origin. We used cupric oxide ligninolysis coupled with gas chromatography/mass spectrometry to show that Curvularia inaequalis, a widely distributed litter ascomycete, chlorinated the aromatic rings of lignin in wood that it was...

Decay and termite resistance of medium density fiberboard (MDF) made from different wood species

Treesearch

S. Nami Kartal; Frederick Green

2003-01-01

Medium density fiberboard (MDF) production worldwide is increasing due to the development of new manufacturing technologies. As a result, MDF products are increasingly utilized in traditional wood applications that require fungal and insect resistance. This study evaluated the ability of white and brown rot fungi and termites to decompose MDF consisting of different...

Chemical modification : a non-toxic approach to wood preservation

Treesearch

Roger M. Rowell

2006-01-01

Wood can be chemically modified to reduce the moisture content of the cell wall and increases decay resistance. As the level of bonded chemical increases, the cell wall equilibrium moisture content decreases and the resistance to attack by white-and brown-rot fungi increases. There is a direct relationship between the decrease in cell wall moisture Content and...

Cytochemical localization of cellulases in decayed and nondecayed wood

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murmanis, L.; Highley, T.L.; Palmer, J.G.

1987-01-01

Sawdust from undecayed western hemlock wood and from wood previously decayed by the brown-rot fungus Poria placenta or by the white-rot fungus Ganoderma applanatum was incubated with commercial cellulase from Trichoderma viride. Samples were treated cytochemically to locate cellulase activity and examined by TEM. Results showed that cellulase degraded undecayed wood extensively, with the attack starting on the outer border of a cell wall and progressing inside. Wood decayed by P. placenta, with or without cellulase incubation, and treated by the cytochemical test showed uniform distribution of electron dense particles throughout the cell walls. In wood decayed by G. applanatum,more » cellulase degradation was similar to that in undecayed wood. From measurements of particle diameter it is suggested that electron dense particles are cellulase. It is concluded that brown-rot and white-rot fungi have different effects on the microstructure of wood. The brown-rot fungus appears to open the wood microstructure so that cellulase can diffuse throughout the degraded tracheid wall.« less

Hijacked: Co-option of host behavior by entomophthoralean fungi

USDA-ARS?s Scientific Manuscript database

Over 700 species of fungi are known to infect and cause disease in insects and other arthropods. The majority of insect pathogenic fungi are classified in the phyla Entomophthoromycotina and Ascomycotina, and many are ecologically important in regulating insect populations. To summarize fungal-inse...

Causative agents of nosocomial mycoses.

PubMed

Tomsiková, A

2002-01-01

In the last few years mycoses have been caused by fungi formerly considered to be harmless for humans. They cause diseases of plants and insects; some of them are also used in the industry. They are now usually called "emerging fungi". We investigated this flora with respect to their potential to cause infections in hospitals. These fungi are present in the air, on medical objects and instrumentation, in the respiratory tract and on the hands of hospital staff; other sources have been identified in the use of iatrogenic methods. Mycotic diseases, their risk factors, their clinical pictures, and spectra of agents were analyzed in 1990-2000; the results were compared with data in the literature. Transplantations were the most frequent risk factors, fungemia and abscess the most frequent clinical picture and filamentous fungi (genera Absidia, Acremonium, Alternaria, Apophysomyces, Aspergillus, Bipolaris, Cladophialophora, Cunninghamella, Exserohilum, Fusarium, Chaetomium, Chrysosporium, Lecythophora, Ochroconis, Paecilomyces, Pythium, Rhizopus, Scedosporium, Scopulariopsis) were the most frequent agents of nosocomial infections. These filamentous fungi and also some yeasts (genera Candida, Cryptococcus, Trichosporon) bring about different clinical syndromes in both immunocompromised and immunocompetent patients.

Investigating niche partitioning of ectomycorrhizal fungi in specialized rooting zones of the monodominant leguminous tree Dicymbe corymbosa.

PubMed

Smith, Matthew E; Henkel, Terry W; Williams, Gwendolyn C; Aime, M Catherine; Fremier, Alexander K; Vilgalys, Rytas

2017-07-01

Temperate ectomycorrhizal (ECM) fungi show segregation whereby some species dominate in organic layers and others favor mineral soils. Weak layering in tropical soils is hypothesized to decrease niche space and therefore reduce the diversity of ectomycorrhizal fungi. The Neotropical ECM tree Dicymbe corymbosa forms monodominant stands and has a distinct physiognomy with vertical crown development, adventitious roots and massive root mounds, leading to multi-stemmed trees with spatially segregated rooting environments: aerial litter caches, aerial decayed wood, organic root mounds and mineral soil. We hypothesized that these microhabitats host distinct fungal assemblages and therefore promote diversity. To test our hypothesis, we sampled D. corymbosa ectomycorrhizal root tips from the four microhabitats and analyzed community composition based on pyrosequencing of fungal internal transcribed spacer (ITS) barcode markers. Several dominant fungi were ubiquitous but analyses nonetheless suggested that communities in mineral soil samples were statistically distinct from communities in organic microhabitats. These data indicate that distinctive rooting zones of D. corymbosa contribute to spatial segregation of the fungal community and likely enhance fungal diversity. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Are stag beetles fungivorous?

PubMed

Tanahashi, Masahiko; Matsushita, Norihisa; Togashi, Katsumi

2009-11-01

Stag beetle larvae generally feed on decaying wood; however, it was unknown whether they can use wood-rotting fungi alone as food. Here, to clarify this, newly hatched larvae of Dorcus rectus (Motschulsky) (Coleoptera: Lucanidae) were reared for 14 days on artificial diets containing a fixed amount of freeze-dried mycelia of the following fungi: Bjerkandera adusta, Trametes versicolor, Pleurotus ostreatus, and Fomitopsis pinicola. The mean incremental gain in larval body mass was greatest on diets containing B. adusta, followed by T. versicolor, P. ostreatus, and F. pinicola. The growth rate of body mass correlated positively with mycelial nitrogen content of the different fungi. It also correlated positively with the mycelial content of B. adusta in the diet. Addition of antibiotics to diets with mycelia nearly halved larval growth, indicating that larvae were able to use fungal mycelia as food without the assistance of associated microbes although the microbes positively affected larval growth. Four newly hatched larvae reared on artificial diets containing B. adusta mycelia developed to the second instar in 21-34 days; and one developed to the third (=final) instar. This study provides evidence that fungi may constitute the bulk of the diet of D. rectus larvae.

Changes in cation concentrations in red spruce wood decayed by brown rot and white rot fungi

Treesearch

A. Ostrofsky; J. Jellison; K.T. Smith; W.C. Shortle

1997-01-01

Red spruce (Picea rubens Sarg.) wood blocks were incubated in modified soil block jars and inoculated with one of nine white rot or brown rot basidiomycetes. Concentrations of calcium, magnesium, potassium, iron, and aluminum were determined using inductively coupled plasma emission spectroscopy in wood incubated 0, 1.5, 4, and 8 months after...

Fungal decay resistance of wood reacted with phosphorus pentoxide-amine system

Treesearch

Hong-Lin Lee; George C. Chen; Roger M. Rowell

2004-01-01

Resistance of wood reacted in situ with phosphorus pentoxide-amine to the brown-rot fungus Gloeophyllum trabeum and white-rot fungus Trametes versicolor was examined. Wood reacted with either octyl, tribromo, or nitro derivatives were more resistant to both fungi. Threshold retention values of phosphoramide-reacted wood to white-rot fungus T. versicolor ranged from 2.9...

Amplicon-Based Sequencing of Soil Fungi from Wood Preservative Test Sites

Treesearch

Grant T. Kirker; Amy B. Bishell; Michelle A. Jusino; Jonathan M. Palmer; William J. Hickey; Daniel L. Lindner

2017-01-01

Soil samples were collected from field sites in two AWPA (American Wood Protection Association) wood decay hazard zones in North America. Two field plots at each site were exposed to differing preservative chemistries via in-ground installations of treated wood stakes for approximately 50 years. The purpose of this study is to characterize soil fungal species and to...

Studying the role of wood-decay fungi in calcium cycling on the Penobscot Experimental Forest: a progress report

Treesearch

Walter C. Shortle; Jody Jellison; Kevin T. Smith; Jonathan S. Schilling

2014-01-01

Depletion of essential mineral nutrients from the rooting zone of trees in northern forests may reduce health and productivity. Long-term field investigations coupled with detailed laboratory studies enhance understanding of the biological processes and suggest means to address potential threats. One such investigation by the U.S. Department of Agriculture, Forest...

Goodbye, Waste! What We Make. Science and Technology Education in Philippine Society.

ERIC Educational Resources Information Center

Philippines Univ., Quezon City. Science Education Center.

This module: (1) discusses the need for disposing of waste safely; (2) provides information and activities on wet and dry wastes; and (3) shows how to prepare, maintain, and study a fertilizer basket (in which fertilizer is made from wet waste). Information on the biology of the basket (including role of bacteria and fungi in the decay process) is…

New Developments in Wood-Destroying Organisms from the International Research Group on Wood Preservation \\t

Treesearch

Elmer L. Schmidt

1991-01-01

New developments in wood-destroying organisms and in wood protection from the 20th annual meeting (May 1989 at Lappeenranta, Finland) of the International Research Group on Wood Preservation (IRG) are highlighted in the areas of biological control of fungi, dry rot, decay mechanisms and product problems, new techniques, insect problems and control, and developments in...

Corrosion of Embedded Metals in Wood: An Overview of Recent Research with Implications for building moisture design

Treesearch

Samuel L. Zelinka

2013-01-01

ASHRAE Standard 160, Criteria for Moisture-Control Design Analysis in Buildings, specifies moisture design criteria in buildings to prevent moisture damage such as fungal activity and corrosion. While there has been much research on mold and decay fungi in wood buildings, it is often overlooked that wet wood is corrosive to the metal screws...

Interactions between stream fungi and bacteria associated with decomposing leaf litter at different levels of nutrient availability

Treesearch

Vladislav Gulis; Keller Suberkropp

2003-01-01

We examined the potential for interactions between aquatic hyphomycetes and bacteria isolated from leaves decaying in a headwater stream. In agar plate assays, culture filtrates of each of 28 aquatic hyphomycete isolates tested (5 species) inhibited bacterial growth (16 Gram-negative bacterial isolates belonging to 6 colony morphotypes were tested). Inhibition of...

Inhibitory effect of gamma irradiation and its application for control of postharvest green mold decay of Satsuma mandarins.

PubMed

Jeong, Rae-Dong; Chu, Eun-Hee; Lee, Gun Woong; Cho, Chuloh; Park, Hae-Jun

2016-10-03

Gamma irradiation has been shown to be effective for the control of postharvest fungi in vitro, but little is known regarding antifungal action, responses to gamma irradiation, and its application to fresh produce. Gamma irradiation was evaluated for its in vitro and in vivo antifungal activity against Penicillium digitatum on Satsuma mandarin fruits. Green mold was inhibited in a dose-dependent manner. Gamma irradiation showed a complete inhibition of spore germination, germ tube elongation, and mycelial growth of P. digitatum, particularly at 1.0kGy. To further investigate the mechanisms by which gamma irradiation inhibits fungal growth, the membrane integrity and cellular leakage of conidia were tested, indicating that gamma irradiation results in the loss of plasma membrane integrity, causing the release of intracellular contents such as soluble proteins. In vivo assays demonstrated that established doses can completely inhibit the growth of fungal pathogens, but such high doses cause severe fruit damage. Thus, to eliminate the negative impact on fruit quality, gamma irradiation at lower doses was evaluated for inhibition of P. digitatum, in combination with a chlorine donor, sodium dichloro-s-triazinetrione (NaDCC). Interestingly, only a combined treatment with 0.4kGy of gamma irradiation and 10ppm of NaDCC exhibited significant synergistic antifungal activity against green mold decay. The mechanisms by which the combined treatment decreased the green mold decay of mandarin fruits can be directly associated with the disruption of cell membrane of the fungal pathogen, which resulted in a loss of cytoplasmic material from the hyphae. These findings suggest that a synergistic effect of combining treatment with gamma irradiation with NaDCC has potential as an antifungal approach to reduce the severity of green mold in mandarin fruits. Copyright © 2016 Elsevier B.V. All rights reserved.

Genome sequences of three phytopathogenic species of the Magnaporthaceae family of fungi

USDA-ARS?s Scientific Manuscript database

Magnaporthaceae is a family of ascomycetes that includes three fungi of great economic importance: Magnaporthe oryzae, Gaeumannomyces graminis var. tritici, and Magnaporthe poae. These three fungi cause widespread disease and loss in cereal and grass crops, including rice blast disease (M. oryzae), ...

Radiocesium Transfer in Forest Insect Communities after the Fukushima Dai-ichi Nuclear Power Plant Accident.

PubMed

Ishii, Yumiko; Hayashi, Seiji; Takamura, Noriko

2017-01-01

To understand radiocesium transfer in the forest insect food web, we investigated the activity concentrations of radiocesium in forest insects in the Fukushima and Ibaraki Prefectures approximately 1.5-2.5 years after the Fukushima Dai-ichi Nuclear Power Plant. We analyzed 34 species of insects sampled from 4 orders and 4 feeding functional groups (herbivore, carnivore, omnivore, and detritivore) from three sites in each prefecture. 137Cs activity concentrations were lowest in herbivorous species and were especially high in detritivorous and omnivorous species that feed on forest litter and fungi. Radiocesium activity concentrations in any given species reflected the degree of contamination of that species' primary food sources since radiocesium activity concentrations were found to be the lowest in leaves and grass and the highest in litter, bark, and fungi. This study confirmed that litter and other highly contaminated forest components such as fungi, decaying wood, bryophytes, and lichens serve as sources of 137Cs transfer into the forest insect community.

Radiocesium Transfer in Forest Insect Communities after the Fukushima Dai-ichi Nuclear Power Plant Accident

PubMed Central

Hayashi, Seiji; Takamura, Noriko

2017-01-01

To understand radiocesium transfer in the forest insect food web, we investigated the activity concentrations of radiocesium in forest insects in the Fukushima and Ibaraki Prefectures approximately 1.5–2.5 years after the Fukushima Dai-ichi Nuclear Power Plant. We analyzed 34 species of insects sampled from 4 orders and 4 feeding functional groups (herbivore, carnivore, omnivore, and detritivore) from three sites in each prefecture. 137Cs activity concentrations were lowest in herbivorous species and were especially high in detritivorous and omnivorous species that feed on forest litter and fungi. Radiocesium activity concentrations in any given species reflected the degree of contamination of that species’ primary food sources since radiocesium activity concentrations were found to be the lowest in leaves and grass and the highest in litter, bark, and fungi. This study confirmed that litter and other highly contaminated forest components such as fungi, decaying wood, bryophytes, and lichens serve as sources of 137Cs transfer into the forest insect community. PMID:28125745

From phaeohyphomycosis to disseminated chromoblastomycosis: A retrospective study of infections caused by dematiaceous fungi.

PubMed

Thomas, E; Bertolotti, A; Barreau, A; Klisnick, J; Tournebize, P; Borgherini, G; Zemali, N; Jaubert, J; Jouvion, G; Bretagne, S; Picot, S

2018-06-01

Infections caused by dematiaceous fungi are more common in tropical and subtropical areas. We aimed to describe the clinical, microbiological and therapeutic aspects of case patients diagnosed at a University Hospital located on an Indian Ocean island. We performed an observational retrospective study of infections caused by dematiaceous fungi diagnosed at the University Hospital of Saint-Pierre, Reunion, from 2000 to 2015. Mycological identifications were performed at the National Reference Center for Invasive Mycosis and Antifungal Agents (Paris). The review of clinical and microbiological data of 11 patients identified revealed that five were infected by dematiaceous fungi. Two had cutaneous phaeohyphomycosis, two had cerebral phaeohyphomycosis and one had cutaneous chromoblastomycosis with brain and potentially medullary dissemination. Skin lesions and cerebral abscesses were quite varied. Infections caused by dematiaceous fungi are rare. Medullary and brain localizations are extremely rare, especially for chromoblastomycosis. Cutaneous manifestations of phaeohyphomycosis are varied; diagnosis is thus more difficult. It is therefore important, when confronted with a chronic tumor-like lesion in endemic areas, to perform a biopsy for pathology and fungal culture. While surgical excision is not always sufficient, medical treatment of these infections is not standardized, but relies on an azole, which can be associated with another antifungal agent. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Taxa-area relationship of aquatic fungi on deciduous leaves.

PubMed

Duarte, Sofia; Cássio, Fernanda; Pascoal, Cláudia; Bärlocher, Felix

2017-01-01

One of the fundamental patterns in macroecology is the increase in the number of observed taxa with size of sampled area. For microbes, the shape of this relationship remains less clear. The current study assessed the diversity of aquatic fungi, by the traditional approach based on conidial morphology (captures reproducing aquatic hyphomycetes) and next generation sequencing (NGS; captures other fungi as well), on graded sizes of alder leaves (0.6 to 13.6 cm2). Leaves were submerged in two streams in geographically distant locations: the Oliveira Stream in Portugal and the Boss Brook in Canada. Decay rates of alder leaves and fungal sporulation rates did not differ between streams. Fungal biomass was higher in Boss Brook than in Oliveira Stream, and in both streams almost 100% of the reads belonged to active fungal taxa. In general, larger leaf areas tended to harbour more fungi, but these findings were not consistent between techniques. Morphospecies-based diversity increased with leaf area in Boss Brook, but not in Oliveira Stream; metabarcoding data showed an opposite trend. The higher resolution of metabarcoding resulted in steeper taxa-accumulation curves than morphospecies-based assessments (fungal conidia morphology). Fungal communities assessed by metabarcoding were spatially structured by leaf area in both streams. Metabarcoding promises greater resolution to assess biodiversity patterns in aquatic fungi and may be more accurate for assessing taxa-area relationships and local to global diversity ratios.

Survey of corticioid fungi in North American pinaceous forests reveals hyperdiversity, underpopulated sequence databases, and species that are potentially ectomycorrhizal.

PubMed

Rosenthal, Lisa M; Larsson, Karl-Henrik; Branco, Sara; Chung, Judy A; Glassman, Sydney I; Liao, Hui-Ling; Peay, Kabir G; Smith, Dylan P; Talbot, Jennifer M; Taylor, John W; Vellinga, Else C; Vilgalys, Rytas; Bruns, Thomas D

2017-01-01

The corticioid fungi are commonly encountered, highly diverse, ecologically important, and understudied. We collected specimens in 60 pine and spruce forests across North America to survey corticioid fungal frequency and distribution and to compile an internal transcribed spacer (ITS) database for the group. Sanger sequences from the ITS region of vouchered specimens were compared with sequences on GenBank and UNITE, and with high-throughput sequence data from soil and roots taken at the same sites. Out of 425 high-quality Sanger sequences from vouchered specimens, we recovered 223 distinct operational taxonomic units (OTUs), the majority of which could not be assigned to species by matching to the BLAST database. Corticioid fungi were found to be hyperdiverse, as supported by the observations that nearly two-thirds of our OTUs were represented by single collections and species estimator curves showed steep slopes with no plateaus. We estimate that 14.8-24.7% of our voucher-based OTUs are likely to be ectomycorrhizal (EM). Corticioid fungi recovered from the soil formed a different community assemblage, with EM taxa accounting for 40.5-58.6% of OTUs. We compared basidioma sequences with EM root tips from our data, GenBank, or UNITE, and with this approach, we reiterate existing speculations that Trechispora stellulata is EM. We found that corticioid fungi have a significant distance-decay pattern, adding to the literature supporting fungi as having geographically structured communities. This study provides a first view of the diversity of this important group across North American pine forests, but much of the biology and taxonomy of these diverse, important, and widespread fungi remains unknown.

Forest Health in the Southeastern United States: Assessment of the State of the Science

DTIC Science & Technology

2008-06-01

pathogens, including imbalances in populations of in- sect pests and root-infesting fungi (e.g., Leptographium species), that may degrade tree physiological...reintroduction exacerbates stress levels and contributes to further root colonization by fungi such as Leptographium sp. Root disease caused by the...Coleoptera: Scolytidae), are likely vectors for the Leptographium/Ophiostomatoid fungi (Eckhardt et al. 2004). Spores of these fungi are not suited to

Infection mechanisms and colonization patterns of fungi on soybean

USDA-ARS?s Scientific Manuscript database

Fungi have many kinds of unique associations with plants. These associations can benefit both the fungus and plant, or can be detrimental to plants and cause disease and even death of the plant. Land plants evolved over 425 million years ago, and fungi have been associated with their evolution over ...

Identification of antimicrobial compound, diketopiperazines, from a Bacillus sp. N strain associated with a rhabditid entomopathogenic nematode against major plant pathogenic fungi.

PubMed

Nishanth Kumar, S; Mohandas, C; Siji, J V; Rajasekharan, K N; Nambisan, Bala

2012-10-01

To purify and characterize antimicrobial compounds from Bacillus sp. strain N associated with rhabditid entomopathogenic nematode (EPN). The cell-free culture filtrate of a bacterium associated with an EPN, Rhabditis (Oscheius) sp., exhibited strong antimicrobial activity. The ethyl acetate extract of the bacterial culture filtrate was purified by silica gel column chromatography to obtain three diketopiperazines (DKPs). The structure and absolute stereochemistry of this compound were determined based on extensive spectroscopic analyses (FABMS, (1) H NMR, (13) C NMR, (1) H-(1) H COSY, (1) H-(13) C HMBC) and Marfey's method. The compounds were identified as cyclo(l-Pro-l-Leu), cyclo(d-Pro-l-Leu) and cyclo(d-Pro-l-Tyr), respectively. Three DKPs were active against all the five fungi tested (Aspergillus flavus, Candida albicans, Fusarium oxysporum, Rhizoctonia solani and Penicillium expansum) and are more effective than the standard fungicide bavistin. The highest activity of 4 μg ml(-1) by cyclo(l-Pro-l-Leu) and cyclo(d-Pro-l-Tyr) was recorded against P. expansum, a plant pathogen responsible for causing postharvest decay of stored apples and oranges. Cyclo(d-Pro-l-Leu) recorded good antibacterial activity against all the four bacteria tested (Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa), and cyclo(l-Pro-l-Leu) and cyclo(d-Pro-l-Tyr) recorded good activity only against Gram-positive bacteria. To our knowledge, this is the first report of antifungal activity of the DKPs against the plant pathogenic fungi F. oxysporum, R. solani and P. expansum. The production of cyclo(l-Pro-l-Leu), cyclo(d-Pro-l-Leu) and cyclo-(d-Pro-l-Tyr) by a bacterium associated with EPN is also reported here for the first time. Isolated DKPs demonstrated high antimicrobial activity against bacteria and fungi, especially against plant pathogenic fungi. We conclude that the bacterium associated with EPN is a promising source of natural bioactive secondary metabolites which may receive great benefit in the field of agriculture. This study is a significant contribution to the knowledge of compounds unique from EPN bacteria as potential sources of new drugs in the agricultural and pharmacological industry. © 2012 The Authors Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

Antibiotic Extraction as a Recent Biocontrol Method for Aspergillus Niger andAspergillus Flavus Fungi in Ancient Egyptian mural paintings

NASA Astrophysics Data System (ADS)

Hemdan, R. Elmitwalli; Fatma, Helmi M.; Rizk, Mohammed A.; Hagrassy, Abeer F.

Biodeterioration of mural paintings by Aspergillus niger and Aspergillus flavus Fungi has been proved in different mural paintings in Egypt nowadays. Several researches have studied the effect of fungi on mural paintings, the mechanism of interaction and methods of control. But none of these researches gives us the solution without causing a side effect. In this paper, for the first time, a recent treatment by antibiotic "6 penthyl α pyrone phenol" was applied as a successful technique for elimination of Aspergillus niger and Aspergillus flavus. On the other hand, it is favorable for cleaning Surfaces of Murals executed by tembera technique from the fungi metabolism which caused a black pigments on surfaces.

Biological method to quantify progressive stages of decay in five commercial woods by Coriolus versicolor.

PubMed

Olfat, A M; Karimi, A N; Parsapajouh, D

2007-04-01

Biologic agar-block method was developed that allowed wood samples to be evaluated and monitored in terms of colonization and development of the decay by Basidiomycetes fungi (Coriolus versicolor) and to be directly classified based on mean mass loss. In this research, the in vitro decay of five commercial woods by Coriolus versicolor was studied by the agar-block method. The selected wood samples were Abies alba, Populus alba, Fagus orientalis, Platanus orientalis and Ulmus glabra. The results demonstrated the strong resistance of Ulmus glabra and the lowest resistance in Fagus orientalis. The mass losses (%) were 16.8 and 42.4%, respectively. There were also a high correlation between the mass loss and apparent damage. Therefore biological evaluation of wood regarding biodegradation and the selection of wood types for various application respects will be of high priority.

Lignocellulosic polysaccharides and lignin degradation by wood decay fungi: the relevance of nonenzymatic Fenton-based reactions.

PubMed

Arantes, Valdeir; Milagres, Adriane M F; Filley, Timothy R; Goodell, Barry

2011-04-01

The brown rot fungus Wolfiporia cocos and the selective white rot fungus Perenniporia medulla-panis produce peptides and phenolate-derivative compounds as low molecular weight Fe³+-reductants. Phenolates were the major compounds with Fe³+-reducing activity in both fungi and displayed Fe³+-reducing activity at pH 2.0 and 4.5 in the absence and presence of oxalic acid. The chemical structures of these compounds were identified. Together with Fe³+ and H₂O₂ (mediated Fenton reaction) they produced oxygen radicals that oxidized lignocellulosic polysaccharides and lignin extensively in vitro under conditions similar to those found in vivo. These results indicate that, in addition to the extensively studied Gloeophyllum trabeum--a model brown rot fungus--other brown rot fungi as well as selective white rot fungi, possess the means to promote Fenton chemistry to degrade cellulose and hemicellulose, and to modify lignin. Moreover, new information is provided, particularly regarding how lignin is attacked, and either repolymerized or solubilized depending on the type of fungal attack, and suggests a new pathway for selective white rot degradation of wood. The importance of Fenton reactions mediated by phenolates operating separately or synergistically with carbohydrate-degrading enzymes in brown rot fungi, and lignin-modifying enzymes in white rot fungi is discussed. This research improves our understanding of natural processes in carbon cycling in the environment, which may enable the exploration of novel methods for bioconversion of lignocellulose in the production of biofuels or polymers, in addition to the development of new and better ways to protect wood from degradation by microorganisms.

The plant cell wall--decomposing machinery underlies the functional diversity of forest fungi

Treesearch

Daniel C. Eastwood; Dimitrios Floudas; Manfred Binder; Andrzej Majcherczyk; Patrick Schneider; Andrea Aerts; Fred O. Asiegbu; Scott E. Baker; Kerrie Barry; Mika Bendiksby; Melanie Blumentritt; Pedro M. Coutinho; Dan Cullen; Ronald P. de Vries; Allen Gathman; Barry Goodell; Bernard Henrissat; Katarina Ihrmark; Havard Kauserud; Annegret Kohler; Kurt LaButti; Alla Lapidus; Jose L. Lavin; Yong-Hwan Lee; Erika Lindquist; Walt Lilly; Susan Lucas; Emmanuelle Morin; Claude Murat; Jose A. Oguiza; Jongsun Park; Antonio G. Pisabarro; Robert Riley; Anna Rosling; Asaf Salamov; Olaf Schmidt; Jeremy Schmutz; Inger Skrede; Jan Stenlid; Ad Wiebenga; Xinfeng Xie; Ursula Kues; David S. Hibbett; Dirk Hoffmeister; Nils Hogberg; Francis Martin; Igor V. Grigoriev; Sarah C. Watkinson

2011-01-01

Brown rot decay removes cellulose and hemicelluloses from wood, residual lignin contributing up to 30% of forest soil carbon, and is derived from an ancestral white rot saprotrophy where both lignin and cellulose are decomposed. Comparative and functional genomics of the “dry rot” fungus Serpula lacrymans, derived from forest ancestors, demonstrated that the evolution...

Comparison of Saproxylic Beetle (Coleoptera) Assemblages in Upland Hardwood and Bottomland Hardwood Forests

Treesearch

Michael D. Warriner; T. Even Nebeker; Steven A. Tucker; Terence L. Schiefer

2004-01-01

Insects dependent upon dead wood, wood-decaying fungi, or other organisms within dead wood for some portion of their life cycle have been termed saproxylic. Beetles comprise a large component of the saproxylic fauna within forests and play vital roles in the initial fragmentation and breakdown of dead woody debris. To evaluate the influence of forest type on saproxylic...

Treated wood in transition : a look at CCA and the candidates to replace it

Treesearch

Stan Lebow; Jerrold Winandy; Donald Bender

2003-01-01

Wood is one of the most versatile and widely used building materials. However, it is also biodegradable, and may be attacked by decay fungi or insects when used in some applications or geographic locations. Uses that allow the wood to frequently become wet, such as embedded posts or other exposed wood members, are familiar examples of applications where wood will...

Treated wood in transition : a look at CCA and the candidates to replace it

Treesearch

Stan Lebow; Jerrold Winandy; Donald Bender

2004-01-01

Wood is one of the most versatile and widely used building materials. However, it is also biodegradable and may be attacked by decay fungi or insects when used in some applications or geographic locations. Uses that allow the wood to frequently become wet, such as embedded posts or other exposed wood members, are familiar examples of applications where wood will...

Performance Characteristics of Borate Fatty Acid Formulations as Mold Inhibitors

Treesearch

Robert D. Coleman; Vina Yang; Carol A. Clausen

2013-01-01

The combination of boric acid (BA) or disodium octaborate tetrahydrate (DOT) and a fatty acid (FA) such as heptanoic, octanoic, and nonanoic acids (C7–C9) is an effective treatment solution for protecting wood structures against mold. BA or DOT alone have substantial potency against insects and decay fungi, but have negligible or no mold inhibitor activity. However,...

Influence of xylem ray integrity and degree of polymerization on bending strength of beech wood decayed by Pleurotus ostreatus and Trametes versicolor

Treesearch

Ehsan Bari; Reza Oladi; Olaf Schmidt; Carol A. Clausen; Katie Ohno; Darrel D. Nicholas; Mehrdad Ghodskhah Daryaei; Maryam Karim

2015-01-01

The scope of this research was to evaluate the influence of xylem ray (XR) and degree of polymerization (DP) of holocellulose in Oriental beech wood (Fagus orientalis Lipsky.) on impact bending strength against two white-rot fungi. Beech wood specimens, exposed to Pleurotus ostreatus and Trametes versicolor, were evaluated for...

Untreated and copper-treated wood soaked in sodium oxalate: effects of decay by copper-tolerant and copper-sensitive fungi

Treesearch

Katie M. Ohno; Grant T. Kirker; Amy B. Bishell; Carol A. Clausen

2017-01-01

Copper is widely used as the primary component in wood protectants because it demonstrates a broad range of biocidal properties. However, a key concern with using copper in wood preservative formulations is the possibility for brown-rot basidiomycetes to resist the toxic effect. Many brown-rot basidiomycetes have evolved mechanisms, like the production and accumulation...

Fungi associated with black mould on baobab trees in southern Africa.

PubMed

Cruywagen, Elsie M; Crous, Pedro W; Roux, Jolanda; Slippers, Bernard; Wingfield, Michael J

2015-07-01

There have been numerous reports in the scientific and popular literature suggesting that African baobab (Adansonia digitata) trees are dying, with symptoms including a black mould on their bark. The aim of this study was to determine the identity of the fungi causing this black mould and to consider whether they might be affecting the health of trees. The fungi were identified by sequencing directly from mycelium on the infected tissue as well as from cultures on agar. Sequence data for the ITS region of the rDNA resulted in the identification of four fungi including Aureobasidium pullulans, Toxicocladosporium irritans and a new species of Rachicladosporium described here as Rachicladosporium africanum. A single isolate of an unknown Cladosporium sp. was also found. These fungi, referred to here as black mould, are not true sooty mould fungi and they were shown to penetrate below the bark of infected tissue, causing a distinct host reaction. Although infections can lead to dieback of small twigs on severely infected branches, the mould was not found to kill trees.

Fungi contamination of drinking water.

PubMed

Al-Gabr, Hamid Mohammad; Zheng, Tianling; Yu, Xin

2014-01-01

Aquatic fungi commonly infest various aqueous environments and play potentially crucial roles in nutrient and carbon cycling. Aquatic fungi also interact with other organisms to influence food web dynamics. In recent decades, numerous studies have been conducted to address the problem of microorganism contamination of water. The major concern has been potential effects on human health from exposure to certain bacteria, viruses, and protozoa that inhabit water and the microbial metabolites,pigments, and odors which are produced in the water, and their effects on human health and animals. Fungi are potentially important contaminants because they produce certain toxic metabolites that can cause severe health hazards to humans and animals. Despite the potential hazard posed by fungi, relatively few studies on them as contaminants have been reported for some countries.A wide variety of fungi species have been isolated from drinking water, and some of them are known to be strongly allergenic and to cause skin irritation, or immunosuppression in immunocompromised individuals (e.g., AIDS, cancer, or organ transplant patients). Mycotoxins are naturally produced as secondary metabolites by some fungi species, and exposure of humans or animals to them can cause health problems. Such exposure is likely to occur from dietary intake of either food,water or beverages made with water. However, mycotoxins, as residues in water,may be aerosolized when showering or when being sprayed for various purposes and then be subject to inhalation. Mycotoxins, or at least some of them, are regarded to be carcinogenic. There is also some concern that toxic mycotoxins or other secondary metabolites of fungi could be used by terrorists as a biochemical weapon by adding amounts of them to drinking water or non drinking water. Therefore, actions to prevent mycotoxin contaminated water from affecting either humans or animals are important and are needed. Water treatment plants may serve to partially accomplish this, by first filtering the water and finally by adding disinfection treatments adequate to remove or mitigate fungi or their toxic metabolites.

Fungal and bacterial community succession differs for three wood types during decay in a forest soil.

PubMed

Prewitt, Lynn; Kang, Youngmin; Kakumanu, Madhavi L; Williams, Mark

2014-08-01

Wood decomposition by soil microorganisms is vital to carbon and nutrient cycles of forested ecosystems. Different wood types decompose at different rates; however, it is not known if there are differences in microbial community succession associated with the decay of different wood types. In this study, the microbial community associated with the decay of pine (decay-susceptible wood), western red cedar (decay resistant) and ACQ-treated pine (Ammoniacal Copper Quaternary, preservative-treated pine for decay resistance) in forest soil was characterized using DNA sequencing, phospholipid fatty acid (PLFA) analysis, and microbial activity over a 26-month period. Bray-Curtis ordination using an internal transcribed spacer (ITS) sequence and PLFA data indicated that fungal communities changed during succession and that wood type altered the pattern of succession. Nondecay fungi decreased over the 26 months of succession; however, by 18 months of decay, there was a major shift in the fungal communities. By this time, Trametes elegans dominated cedar and Phlebia radiata dominated pine and ACQ-treated pine. The description of PLFA associated with ACQ-treated pine resembled cedar more than pine; however, both PLFA and ITS descriptions indicated that fungal communities associated with ACQ-treated pine were less dynamic, perhaps a result of the inhibition by the ACQ preservative, compared with pine and cedar. Overall, fungal community composition and succession were associated with wood type. Further research into the differences in community composition will help to discern their functional importance to wood decay.

Sea salts as a potential source of food spoilage fungi.

PubMed

Biango-Daniels, Megan N; Hodge, Kathie T

2018-02-01

Production of sea salt begins with evaporation of sea water in shallow pools called salterns, and ends with the harvest and packing of salts. This process provides many opportunities for fungal contamination. This study aimed to determine whether finished salts contain viable fungi that have the potential to cause spoilage when sea salt is used as a food ingredient by isolating fungi on a medium that simulated salted food with a lowered water activity (0.95 a w ). The viable filamentous fungi from seven commercial salts were quantified and identified by DNA sequencing, and the fungal communities in different salts were compared. Every sea salt tested contained viable fungi, in concentrations ranging from 0.07 to 1.71 colony-forming units per gram of salt. In total, 85 fungi were isolated representing seven genera. One or more species of the most abundant genera, Aspergillus, Cladosporium, and Penicillium was found in every salt. Many species found in this study have been previously isolated from low water activity environments, including salterns and foods. We conclude that sea salts contain many fungi that have potential to cause food spoilage as well as some that may be mycotoxigenic. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Toxic effects of chlorate on three plant species inoculated with arbuscular mycorrhizal fungi.

PubMed

Li, Huashou; Zhang, Xiuyu; Lin, Chuxia; Wu, Qitang

2008-11-01

Pot experiments were conducted to examine the toxic effects of chlorate on bermudagrass, bahiagrass, and longan seedling with a focus on arbuscular mycorrhizal fungi-plant associations. The results show that application of chlorate could cause slight soil acidification, but the resulting pH was still around 5.5, which is unlikely to adversely affect plant growth. Increase in the application rate of chlorate resulted in a decrease in colonization rate of arbuscular mycorrhizal fungi in plant roots, P uptake by the plants and plant biomass. This appears to suggest that the reduction in plant growth may be related to impeded uptake of P by the plants due to the failure of the plants to form sufficient mycorrhizal associations when chlorate is in sufficient amounts to cause toxicity to arbuscular mycorrhizal fungi. Under the experimental conditions set for this study, bermudagrass suffered from stronger chlorate stress than bahiagrass and longan seedling did in terms of plant-arbuscular mycorrhizal fungi (AMF) symbiosis development.

Gas chromatographic determination of 1.8-naphthalimide, N-hydroxy-1.8- naphthalimide (N,N-naphthaloylhydroxylamine) and the sodium salt of N-hydroxy-1.8-naphthalimide

Treesearch

Eckhard Melcher; Frederick Green

2003-01-01

A number of naphthalimide (NI) derivatives are used as efficient laser dyes, in medicine or in transmission electron microscopy. Only N,N- naphthaloylhydroxylamine (NHA) has been shown to be an effective wood preservative against wood decay fungi and termite damage. However, limited information is available concerning the analytical detection of Nl-derivatives in...

Treatability of SPF framing lumber with CCA and borate preservatives

Treesearch

Cherilyn Hatfield

2005-01-01

There is increasing interest in preservative pressure-treatment of framing lumber to prevent attack by decay fungi and insects. However, the Spruce– pine–Fir species group that is often used in framing construction can be difficult to penetrate with preservatives. We compared solution uptake and penetration of boron and copper from a borax–copper (BC) preservative to...

Changes in selected enzyme activities during growth of pure and mixed cultures of the white-rot decay fungus Trametes versicolor and the potential biocontrol fungus Trichoderma harzianum.

PubMed

Freitag, M; Morrell, J J

1992-04-01

Two filamentous fungi, the white-rot fungus Trametes versicolor and the soil fungus and potential biocontrol organism Trichoderma harzianum, have been grown in pure and mixed cultures on low-N (0.4 mM) and high-N (4 mM) defined synthetic media to determine the activities of selected wood-degrading enzymes such as cellobiase, cellulase, laccase, and peroxidases. Growth characteristics and enzyme activities were examined for potential correlations. Such correlations would allow the use of simple enzyme assays for measuring biomass development and would facilitate predictions about competitiveness of species in mixed fungal cultures. Our results show that while laccase and Poly Red-478 peroxidase activities indicate survival of the decay fungus, none of the monitored extracellular enzymes can serve as a quantitative indicator for biomass accumulation. As expected, the level of available nitrogen affected the production of the enzymes monitored: in low-N media, specific cellobiase, specific cellulase, and peroxidase activities were enhanced, while laccase activities were reduced. Most importantly, laccase activities of Trametes versicolor, and to a smaller extent, cellobiase activities of both fungi, were significantly induced in mixed cultures of Trametes versicolor and Trichoderma harzianum.

Characterizing butt-rot fungi on USA-affiliated islands in the western Pacific

Treesearch

Phil Cannon; Ned B. Klopfenstein; Robert L. Schlub; Mee-Sook Kim; Yuko Ota; Norio Sahashi; Roland J. Quitugua; John W. Hanna; Amy L. Ross-Davis; J. D. Sweeney

2014-01-01

Ganoderma and Phellinus are genera that commonly cause tree butt-rot on USA-affiliated islands of the western Pacific. These fungal genera can be quite prevalent, especially in older mangrove stands. Although the majority of infections caused by these fungi lead to severe rotting of the heartwood, they typically do not directly kill the living tissues of the sapwood,...

Control of bull’s-eye rot of apple caused by Neofabraea perennans and Neofabraea kienholzii using pre- and postharvest fungicides

USDA-ARS?s Scientific Manuscript database

Bull’s-eye rot is a major postharvest disease of apple caused by several fungi belonging to the Neofabraea and Phlyctema genera. Chemical control of these fungi is a crucial component of disease management for apples that are conventionally grown. The efficacy of several pre-harvest and postharvest ...

Athlete's foot and onychomycosis caused by Hendersonula toruloidea.

PubMed

Abramson, C

1990-08-01

Fungi other than the dermatophytes can cause infections of the foot, toes and toenails that simulate classic "athlete's foot." Unless diagnosed culturally and morphologically by the clinical laboratory, treatment failures may occur. The saprophyte Hendersonula toruloidea as well as other fungi and yeasts reported to cause such infections have been shown to be clinically indistinguishable from classic dermatophytic "athlete's foot." The clinical and laboratory diagnosis of these types of foot infections caused by Hendersonula toruloidea are described. Specific transport media required for laboratory diagnosis and therapeutic alternatives are reviewed.

40 CFR 165.43 - Scope of pesticide products included.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., fungi, protozoa, algae, or slime; and (B) In the intended use is subject to a tolerance under section... from contamination, fouling, or deterioration caused by bacteria, viruses, fungi, protozoa, algae, or...

40 CFR 165.43 - Scope of pesticide products included.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., fungi, protozoa, algae, or slime; and (B) In the intended use is subject to a tolerance under section... from contamination, fouling, or deterioration caused by bacteria, viruses, fungi, protozoa, algae, or...

40 CFR 165.43 - Scope of pesticide products included.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., fungi, protozoa, algae, or slime; and (B) In the intended use is subject to a tolerance under section... from contamination, fouling, or deterioration caused by bacteria, viruses, fungi, protozoa, algae, or...

40 CFR 165.43 - Scope of pesticide products included.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., fungi, protozoa, algae, or slime; and (B) In the intended use is subject to a tolerance under section... from contamination, fouling, or deterioration caused by bacteria, viruses, fungi, protozoa, algae, or...

Antagonistic evaluation of Trichodermaviride and Aspergillusflavus against wood-decay fungus Pleurotusostreatus

NASA Astrophysics Data System (ADS)

Erwin; Iskandar, E.; Husien, N.

2018-04-01

Pleurotusostreatus cultivation is often limited by the presence of antagonistic microorganisms that can also grow together on a variety of substrates that are used as growth media of P. ostreatus. As a preliminary study, this research aims to evaluate the antagonism of Trichodermaviride and Aspergillusflavus in interacting with the P.ostreatus fungus by in-vitro. An antagonism test using a dual culture method of these fungi with 1 month incubation time on Poteto Dextrose Agar (PDA) media was performed. Evaluation of the antagonistic properties of these fungi is conducted through macroscopic and microscopic observations. Macroscopically, the growth of T. viride and A. flavus mycelium showed that both colonies were more dominant than P. ostreatus colonies. Microscopically, hyphae of T. viride and A. flavus indicate the presence of very strong micoparasitic properties that characterized by attachment and convolution of both hyphae to P. ostreatus hyphae. It was concluded thatthe growth of T. viride and A. flavus fungi was more dominant and had potential as an inhibiting agent of P. ostreatus fungal growth, respectively, in dual culture on PDA media.

[Diversity and distribution character of wood-rotting fungi in the secondary forest ecosystem of Liaodong areas, Northeast China].

PubMed

Zhang, Li Yan; Wei, Yu Lian; Li, Tong

2016-12-01

During July to September of 2013, field investigations and specimen collections on wood-rotting fungi were carried from three sites in the secondary forests (Qingyuan forest farm, Laotudingzi National Nature Reserve and Baishilaizi Nature Reserve) of eastern Liaoning Province. A total of 1062 specimens were collected and recorded, and 92 species were identified, belonging to48 genera. Among the three studying sites, Baishilaizi Nature Reserve had the most abundant polypore species and the Shannon diversity index was 4.04. The species biogeography of eastern Liaoning could be divided into 4 groups at genus level. The main elements were North temperate element and cosmopolitan element, and floristic analysis showed a distinct north temperate character. White rot species were the dominant decomposers here. Most species distributed in the fallen wood with decay stages 2 and 3. The wood dominant hosts of wood-rotting fungi were the Acer genus in the secondary forests of eastern Liaoning Province, and 243 specimens were collected from maples, occupying 23.2% of the total.

Host preference and species richness of wood-inhabiting aphyllophoraceous fungi in a cool temperate area of Japan.

PubMed

Yamashita, Satoshi; Hattori, Tsutomu; Abe, Hisashi

2010-01-01

We examined the species richness and host utilization patterns of wood-inhabiting aphyllophoraceous fungi (polypores and related fungi) in an old-growth beech and oak forest in a cool, temperate area of Japan. Coarse woody debris (CWD) > or = 20 cm diam within a 6 ha plot was surveyed in Sep 2002. Tree genus, diameter, decay class and tree part of CWD samples were recorded. Fruiting bodies of aphyllophoraceous fungi that arose from the CWD were surveyed three times and identified to species. In total 256 CWD samples from 12 tree genera were surveyed with Quercus being the most frequent followed by Castanea and Fagus. From 196 CWD samples we recorded 436 wood-inhabiting fungi belonging to 63 species. Fifteen fungal species had at least 10 records, with Hymenochaete rubiginosa, Daedalea dickinsii, Xylobolus frustulatus, Rigidoporus cinereus and the small form of Fomes fomentarius being the most frequent. The number of fungal species that appeared on Fagus was significantly larger than that on Castanea, when the number of fruiting bodies collected was at least 50. The occurrences of the 15 dominant fungal species, except Trametes versicolor, were related to traits of the CWD. Tree genus was a predictor variable that affected the appearance of 11 of the 15 species of wood-inhabiting fungi. Only the tree part was selected for the models of Rigidoporus eminens, Schizopora flavipora and Stereum ostrea. Our results suggest that tree genus and tree part are important factors determining fungal community structure because these were selected as complementary predictor variables. Both oak and beech appear to be the most important tree genera for maintaining wood-inhabiting fungal species richness because the fungal flora formed on oak CWD is nearly complementary to those on chestnut, with low fungal species richness.

Interactions between cranberries and fungi: the proposed function of organic acids in virulence suppression of fruit rot fungi

PubMed Central

Tadych, Mariusz; Vorsa, Nicholi; Wang, Yifei; Bergen, Marshall S.; Johnson-Cicalese, Jennifer; Polashock, James J.; White, James F.

2015-01-01

Cranberry fruit are a rich source of bioactive compounds that may function as constitutive or inducible barriers against rot-inducing fungi. The content and composition of these compounds change as the season progresses. Several necrotrophic fungi cause cranberry fruit rot disease complex. These fungi remain mostly asymptomatic until the fruit begins to mature in late August. Temporal fluctuations and quantitative differences in selected organic acid profiles between fruit of six cranberry genotypes during the growing season were observed. The concentration of benzoic acid in fruit increased while quinic acid decreased throughout fruit development. In general, more rot-resistant genotypes (RR) showed higher levels of benzoic acid early in fruit development and more gradual decline in quinic acid levels than that observed in the more rot-susceptible genotypes. We evaluated antifungal activities of selected cranberry constituents and found that most bioactive compounds either had no effects or stimulated growth or reactive oxygen species (ROS) secretion of four tested cranberry fruit rot fungi, while benzoic acid and quinic acid reduced growth and suppressed secretion of ROS by these fungi. We propose that variation in the levels of ROS suppressive compounds, such as benzoic and quinic acids, may influence virulence by the fruit rot fungi. Selection for crops that maintain high levels of virulence suppressive compounds could yield new disease resistant varieties. This could represent a new strategy for control of disease caused by necrotrophic pathogens that exhibit a latent or endophytic phase. PMID:26322038

40 CFR 165.63 - Scope of pesticide products included.

Code of Federal Regulations, 2011 CFR

2011-07-01

... caused by bacteria, viruses, fungi, protozoa, algae, or slime; and (B) In the intended use is subject to... bacteria, viruses, fungi, protozoa, algae, or slime. (ii) The labeling of the pesticide product includes...

40 CFR 165.63 - Scope of pesticide products included.

Code of Federal Regulations, 2014 CFR

2014-07-01

... caused by bacteria, viruses, fungi, protozoa, algae, or slime; and (B) In the intended use is subject to... bacteria, viruses, fungi, protozoa, algae, or slime. (ii) The labeling of the pesticide product includes...

40 CFR 165.63 - Scope of pesticide products included.

Code of Federal Regulations, 2013 CFR

2013-07-01

... caused by bacteria, viruses, fungi, protozoa, algae, or slime; and (B) In the intended use is subject to... bacteria, viruses, fungi, protozoa, algae, or slime. (ii) The labeling of the pesticide product includes...

40 CFR 165.63 - Scope of pesticide products included.

Code of Federal Regulations, 2012 CFR

2012-07-01

... caused by bacteria, viruses, fungi, protozoa, algae, or slime; and (B) In the intended use is subject to... bacteria, viruses, fungi, protozoa, algae, or slime. (ii) The labeling of the pesticide product includes...

Glucanase and Chitinase from Some Isolates of Endophytic Fungus Trichoderma spp.

NASA Astrophysics Data System (ADS)

Prasetyawan, Sasangka; Sulistyowati, Lilik; Aulanni'am

2018-01-01

Endophytic fungi are those fungi that are able to grow in plant tissue without causing symptoms of disease. It is thought that these fungi may confer on the host plants degree of resistance to parasitic invasion. Endophytic fungi have been isolated from stem tissue and these fungi are known to be antagonistic to pathogenic fungi. These endophytes produce chitinase and β-1,3-glucanase enzymes. Based on the fact that chitin and β-1,3-glucan are the main skeletal polysaccharides of the cell walls of fungal patogen. The aim of this research is to do potential test on some of isolates of Trichoderma’s endophytic (L-1, L-2, Is-1, Is-2 and Is-7) in the chitinase and β-1,3-glucanase activity in effort to determine endophytic which be chossen to be gene resource for the next research. The gene will be transformed to citrus plant japanese citroen in effort to make citrus plant transgenic resistance to phytopatogenic invasion. The result of this research is endofit namely L-1 is the most potential endophytic fungi with chitinase activities is 4,8 10-2 Unit and glucanase 24,2. 1012 Unit. The addition of chitin and cell wall of phytophtora causes chitinase activity significantly increase, and also addition of laminarin and cell wall of phytophtora makes glucanase activity increase.

Clonal reproduction in fungi

PubMed Central

Taylor, John W.; Hann-Soden, Christopher; Branco, Sara; Sylvain, Iman; Ellison, Christopher E.

2015-01-01

Research over the past two decades shows that both recombination and clonality are likely to contribute to the reproduction of all fungi. This view of fungi is different from the historical and still commonly held view that a large fraction of fungi are exclusively clonal and that some fungi have been exclusively clonal for hundreds of millions of years. Here, we first will consider how these two historical views have changed. Then we will examine the impact on fungal research of the concept of restrained recombination [Tibayrenc M, Ayala FJ (2012) Proc Natl Acad Sci USA 109 (48):E3305–E3313]. Using animal and human pathogenic fungi, we examine extrinsic restraints on recombination associated with bottlenecks in genetic variation caused by geographic dispersal and extrinsic restraints caused by shifts in reproductive mode associated with either disease transmission or hybridization. Using species of the model yeast Saccharomyces and the model filamentous fungus Neurospora, we examine intrinsic restraints on recombination associated with mating systems that range from strictly clonal at one extreme to fully outbreeding at the other and those that lie between, including selfing and inbreeding. We also consider the effect of nomenclature on perception of reproductive mode and a means of comparing the relative impact of clonality and recombination on fungal populations. Last, we consider a recent hypothesis suggesting that fungi thought to have the most severe intrinsic constraints on recombination actually may have the fewest. PMID:26195774

An integrated genomic and transcriptomic survey of mucormycosis-causing fungi

PubMed Central

Chibucos, Marcus C.; Soliman, Sameh; Gebremariam, Teclegiorgis; Lee, Hongkyu; Daugherty, Sean; Orvis, Joshua; Shetty, Amol C.; Crabtree, Jonathan; Hazen, Tracy H.; Etienne, Kizee A.; Kumari, Priti; O'Connor, Timothy D.; Rasko, David A.; Filler, Scott G.; Fraser, Claire M.; Lockhart, Shawn R.; Skory, Christopher D.; Ibrahim, Ashraf S.; Bruno, Vincent M.

2016-01-01

Mucormycosis is a life-threatening infection caused by Mucorales fungi. Here we sequence 30 fungal genomes, and perform transcriptomics with three representative Rhizopus and Mucor strains and with human airway epithelial cells during fungal invasion, to reveal key host and fungal determinants contributing to pathogenesis. Analysis of the host transcriptional response to Mucorales reveals platelet-derived growth factor receptor B (PDGFRB) signaling as part of a core response to divergent pathogenic fungi; inhibition of PDGFRB reduces Mucorales-induced damage to host cells. The unique presence of CotH invasins in all invasive Mucorales, and the correlation between CotH gene copy number and clinical prevalence, are consistent with an important role for these proteins in mucormycosis pathogenesis. Our work provides insight into the evolution of this medically and economically important group of fungi, and identifies several molecular pathways that might be exploited as potential therapeutic targets. PMID:27447865

Survey of subterranean termites (Isoptera: Rhinotermitidae) in a managed silvicultural plantation in Portugal, using a line-intersection method (LIS).

PubMed

Nobre, T; Nunes, L; Bignell, D E

2009-02-01

Subterranean termites (Reticulitermes grassei) were surveyed over successive seasons in a managed eucalyptus plantation in southeastern Portugal for 26 months. Termite activity in seven diameter categories of lying dead wood was investigated by a modified line intersection method (LIS). Each item sampled was inspected and assessed for termite attack and for general (i.e. fungal) decay status using standard protocols. Line intersection is quantitative to the extent that it can link foraging and decay parameters to woody biovolume. It was found that termites selected items with larger diameter, the observed trend showing an exponential character with greater termite attack as diameter increased. Attack by termites was positively associated with prior decay by fungi. A clear positive relationship was shown between rainfall and total woody biovolume containing live termites, underlining the importance of moisture for termite activity. Subterranean termites appeared to be important wood decomposers in the woodland studied, with an average of 30% of lying dead wood branches showing signs of termite attack.

Proteomic responses of fruits to environmental stresses

PubMed Central

Chan, Zhulong

2012-01-01

Fruits and vegetables are extremely susceptible to decay and easily lose commercial value after harvest. Different strategies have been developed to control postharvest decay and prevent quality deterioration during postharvest storage, including cold storage, controlled atmosphere (CA), and application of biotic and abiotic stimulus. In this review, mechanisms related to protein level responses of host side and pathogen side were characterized. Protein extraction protocols have been successfully developed for recalcitrant, low protein content fruit tissues. Comparative proteome profiling and functional analysis revealed that defense related proteins, energy metabolism, and antioxidant pathway played important roles in fruits in response to storage conditions and exogenous elicitor treatments. Secretome of pathogenic fungi has been well-investigated and the results indicated that hydrolytic enzymes were the key virulent factors for the pathogen infection. These protein level changes shed new light on interaction among fruits, pathogens, and environmental conditions. Potential postharvest strategies to reduce risk of fruit decay were further proposed based on currently available proteomic data. PMID:23335934

Symbiotic soil fungi enhance ecosystem resilience to climate change.

PubMed

Martínez-García, Laura B; De Deyn, Gerlinde B; Pugnaire, Francisco I; Kothamasi, David; van der Heijden, Marcel G A

2017-12-01

Substantial amounts of nutrients are lost from soils through leaching. These losses can be environmentally damaging, causing groundwater eutrophication and also comprise an economic burden in terms of lost agricultural production. More intense precipitation events caused by climate change will likely aggravate this problem. So far it is unresolved to which extent soil biota can make ecosystems more resilient to climate change and reduce nutrient leaching losses when rainfall intensity increases. In this study, we focused on arbuscular mycorrhizal (AM) fungi, common soil fungi that form symbiotic associations with most land plants and which increase plant nutrient uptake. We hypothesized that AM fungi mitigate nutrient losses following intensive precipitation events (higher amount of precipitation and rain events frequency). To test this, we manipulated the presence of AM fungi in model grassland communities subjected to two rainfall scenarios: moderate and high rainfall intensity. The total amount of nutrients lost through leaching increased substantially with higher rainfall intensity. The presence of AM fungi reduced phosphorus losses by 50% under both rainfall scenarios and nitrogen losses by 40% under high rainfall intensity. Thus, the presence of AM fungi enhanced the nutrient interception ability of soils, and AM fungi reduced the nutrient leaching risk when rainfall intensity increases. These findings are especially relevant in areas with high rainfall intensity (e.g., such as the tropics) and for ecosystems that will experience increased rainfall due to climate change. Overall, this work demonstrates that soil biota such as AM fungi can enhance ecosystem resilience and reduce the negative impact of increased precipitation on nutrient losses. © 2017 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

Discrimination between Pseudogymnoascus destructans, other dermatophytes of cave-dwelling bats, and related innocuous keratinophilic fungi based on electronic-nose/GC signatures of VOC-metabolites produced in culture

Treesearch

Alphus Dan Wilson; Lisa Beth Forse

2017-01-01

White-nose syndrome (WNS), caused by the fungal dermatophyte (Pseudogymnoascus destructans), is considered the most important disease affecting hibernating bats in North America. The identification of dermatophytic fungi, isolated from the skins of cave-dwelling bat species, is necessary to distinguish pathogenic (disease-causing) microbes from those that are innocuous...

Simulated nitrogen deposition causes a decline of intra- and extraradical abundance of arbuscular mycorrhizal fungi and changes in microbial community structure in northern hardwood forests

Treesearch

Linda T.A. van Diepen; Erik A. Lilleskov; Kurt S. Pregitzer; R. Michael Miller

2010-01-01

Increased nitrogen (N) deposition caused by human activities has altered ecosystem functioning and biodiversity. To understand the effects of altered N availability, we measured the abundance of arbuscular mycorrhizal fungi (AMF) and the microbial community in northern hardwood forests exposed to long-term (12 years) simulated N deposition (30 kg N ha-1...

Comparative Genomics of Early-Diverging Mushroom-Forming Fungi Provides Insights into the Origins of Lignocellulose Decay Capabilities.

PubMed

Nagy, László G; Riley, Robert; Tritt, Andrew; Adam, Catherine; Daum, Chris; Floudas, Dimitrios; Sun, Hui; Yadav, Jagjit S; Pangilinan, Jasmyn; Larsson, Karl-Henrik; Matsuura, Kenji; Barry, Kerrie; Labutti, Kurt; Kuo, Rita; Ohm, Robin A; Bhattacharya, Sukanta S; Shirouzu, Takashi; Yoshinaga, Yuko; Martin, Francis M; Grigoriev, Igor V; Hibbett, David S

2016-04-01

Evolution of lignocellulose decomposition was one of the most ecologically important innovations in fungi. White-rot fungi in the Agaricomycetes (mushrooms and relatives) are the most effective microorganisms in degrading both cellulose and lignin components of woody plant cell walls (PCW). However, the precise evolutionary origins of lignocellulose decomposition are poorly understood, largely because certain early-diverging clades of Agaricomycetes and its sister group, the Dacrymycetes, have yet to be sampled, or have been undersampled, in comparative genomic studies. Here, we present new genome sequences of ten saprotrophic fungi, including members of the Dacrymycetes and early-diverging clades of Agaricomycetes (Cantharellales, Sebacinales, Auriculariales, and Trechisporales), which we use to refine the origins and evolutionary history of the enzymatic toolkit of lignocellulose decomposition. We reconstructed the origin of ligninolytic enzymes, focusing on class II peroxidases (AA2), as well as enzymes that attack crystalline cellulose. Despite previous reports of white rot appearing as early as the Dacrymycetes, our results suggest that white-rot fungi evolved later in the Agaricomycetes, with the first class II peroxidases reconstructed in the ancestor of the Auriculariales and residual Agaricomycetes. The exemplars of the most ancient clades of Agaricomycetes that we sampled all lack class II peroxidases, and are thus concluded to use a combination of plesiomorphic and derived PCW degrading enzymes that predate the evolution of white rot. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

HOW to Identify and Control Stem Rusts of Jack Pine

Treesearch

Kathryn Robbins; Dale K. Smeltzer; D. W. French

Damage to jack pine caused by rust fungi includes growth reduction, cankers, death (by girdling or wind breakage), and creation of entryways for other fungi and insects. Seedlings and saplings are more seriously affected than older trees.

[Concentration and Size Distribution of Bioaerosols in Indoor Environment of University Dormitory During the Plum Rain Period].

PubMed

Liu, Ting; Li, Lu; Zhang, Jia-quan; Zhan, Chang-lin; Liu, Hong-xia; Zheng, Jing-ru; Yao, Rui-zhen; Cao, Jun-ji

2016-04-15

Bioaerosols of university dormitory can spread through air and cause a potential health risk for student staying in indoor environment. To quantify the characteristics of bioaerosols in indoor environment of university dormitory, concentration and size distribution of culturable bioaerosols were detected during the plum rain period, the correlations of culturable bioaerosol with concentration of particulate matter, the ambient temperature and relative humidity were analyzed using Spearman's correlation coefficient and finally the changes of size distribution of culturable bioaerosol caused by activities of students were detected. The results showed that the mean concentrations of culturable airborne bacteria and fungi were (2133 +/- 1617) CFUm' and (3111 +/- 2202) CFU x m(-3). The concentrations of culturable airborne bacteria and fungi exhibited negative correlation with PM1, PM2.5, and PM10, respectively. The respirable fractions of bacteria exhibited positive correlation with PM2.5, and the respirable fractions of fungi exhibited significant positive correlation with PM10. Ambient temperature had positive correlation with culturable airborne bacteria and fungi, and relative humidity had negative correlation with culturable airborne bacteria and fungi. In the afternoon, concentrations of culturable airborne fungi in indoor environment of university dormitory significantly increased, and the size distribution of culturable hioaerosols was different in the morning and afternoon.

Trichocomaceae: biodiversity of Aspergillus spp and Penicillium spp residing in libraries.

PubMed

Leite, Diniz Pereira; Yamamoto, Ana Caroline Akeme; Amadio, Janaína Vasconcellos Ribeiro de Souza; Martins, Evelin Rodrigues; do Santos, Fábio Alexandre Leal; Simões, Sara de Almeida Alves; Hahn, Rosane Christine

2012-10-19

Atmospheric air is the most common vehicle for the dispersion of fungi. Fungi belonging to the genera Aspergillus and Penicillium are cosmopolitan and are classified in the family Trichocomaceae. Species of the genera are commonly found in soil, decaying organic materials, animal feed, stored grains, and other materials. This study aimed to determine the taxonomic diversity of airborne fungi of the genera Aspergillus and Penicillium residing in the dust of library environments to contribute to current knowledge of these characteristic genera. Three libraries in the city of Cuiaba, State of Mato Grosso, Brazil, were selected as the study areas. A total of 168 samples were collected at randomized sites within each library in areas containing journals, archives, in study rooms, and in collection storage areas in two different periods, the dry season (n = 42)  and the rainy season (n = 42). Samples were collected by exposing Petri dishes containing Sabouraud agar with chloramphenicol to the environmental air. Additional samples were collected with sterile swabs which were rubbed over the surface of randomly chosen books on the shelves; the swabs were subsequently incubated in the laboratory. The genus Aspergillus was highlighted as one of the principal airborne fungi present in indoor environments. Aspergillus spp was identified in 1,277 (89.6%) samples and Penicillium spp in 148 (10.4%). The dry period exhibited a greater number of isolates of the two taxons.

Reduction of Fusarium rot and maintenance of fruit quality in melon using eco-friendly hot water treatment.

PubMed

Sui, Yuan; Droby, Samir; Zhang, Danfeng; Wang, Wenjie; Liu, Yongsheng

2014-12-01

Significant losses in harvested fruit can be directly attributable to decay fungi and quality deterioration. Hot water treatment (HWT) has been demonstrated to be an effective and economic environment-friendly approach for managing postharvest decay and maintaining fruit quality. In this study, the effects of HWT (45 °C for 10, 15, 20, and 25 min) on in vitro growth of Fusarium oxysporum, in vivo Fusarium rot, and natural decay of melon were investigated. HWT inhibited spore germination and germ tube elongation of F. oxysporum. Protein impairment and ATP consumption triggered by HWT contributed to the inhibitory effect. Results of in vivo studies showed that HWT effectively controlled Fusarium rot and natural decay of melon. Correspondingly, HWT induced a significant increase in content of total phenolic compounds and lignin of melon. These findings indicate that the effects of HWT on Fusarium rot may be associated with the direct fungal inhibition and the elicitation of defense responses in fruit. Importantly, HWT used in this study had beneficial effects on fruit quality as well. HWT may represent an effective non-chemical approach for management of postharvest Fusarium rot.

In Vitro Antifungal Activity of Hexahydropyrimidine Derivatives against the Causative Agents of Dermatomycosis

PubMed Central

Caneschi, César A.; Senra, Mônica P.; Carvalho, Gustavo S. G.; da Silva, Adilson D.

2017-01-01

Nitrogenated heterocyclic compounds are present in both natural and synthetic drugs, and hexahydropyrimidine derivatives may prove to be efficient in treating dermatomycosis causing fungi. This study evaluated the antifungal activity of four hexahydropyrimidine derivatives against the dermatomycosis causing fungi. These derivatives were synthesized, characterized, and assessed in terms of their activity against Trichophyton mentagrophytes, Microsporum canis, Microsporum gypseum, Trichophyton rubrum, Fusarium oxysporum, and Epidermophyton floccosum between concentrations 7.8 and 1,000 μg mL−1. Scanning electron micrographs were assessed for the active derivatives and reference drugs, and these micrographs revealed that new agents cause morphological changes in fungi. The derivatives HHP1, HHP3, and HHP4 revealed poor activity against the four fungal strains (MICs range 500–1000 μg mL−1). Compound HHP3 was found to be the best potential antifungal agent among those tested and was the most effective among all the active derivatives that caused morphological changes in the susceptible strains. PMID:29226215

The Paleozoic origin of enzymatic lignin decomposition reconstructed from 31 fungal genomes.

PubMed

Floudas, Dimitrios; Binder, Manfred; Riley, Robert; Barry, Kerrie; Blanchette, Robert A; Henrissat, Bernard; Martínez, Angel T; Otillar, Robert; Spatafora, Joseph W; Yadav, Jagjit S; Aerts, Andrea; Benoit, Isabelle; Boyd, Alex; Carlson, Alexis; Copeland, Alex; Coutinho, Pedro M; de Vries, Ronald P; Ferreira, Patricia; Findley, Keisha; Foster, Brian; Gaskell, Jill; Glotzer, Dylan; Górecki, Paweł; Heitman, Joseph; Hesse, Cedar; Hori, Chiaki; Igarashi, Kiyohiko; Jurgens, Joel A; Kallen, Nathan; Kersten, Phil; Kohler, Annegret; Kües, Ursula; Kumar, T K Arun; Kuo, Alan; LaButti, Kurt; Larrondo, Luis F; Lindquist, Erika; Ling, Albee; Lombard, Vincent; Lucas, Susan; Lundell, Taina; Martin, Rachael; McLaughlin, David J; Morgenstern, Ingo; Morin, Emanuelle; Murat, Claude; Nagy, Laszlo G; Nolan, Matt; Ohm, Robin A; Patyshakuliyeva, Aleksandrina; Rokas, Antonis; Ruiz-Dueñas, Francisco J; Sabat, Grzegorz; Salamov, Asaf; Samejima, Masahiro; Schmutz, Jeremy; Slot, Jason C; St John, Franz; Stenlid, Jan; Sun, Hui; Sun, Sheng; Syed, Khajamohiddin; Tsang, Adrian; Wiebenga, Ad; Young, Darcy; Pisabarro, Antonio; Eastwood, Daniel C; Martin, Francis; Cullen, Dan; Grigoriev, Igor V; Hibbett, David S

2012-06-29

Wood is a major pool of organic carbon that is highly resistant to decay, owing largely to the presence of lignin. The only organisms capable of substantial lignin decay are white rot fungi in the Agaricomycetes, which also contains non-lignin-degrading brown rot and ectomycorrhizal species. Comparative analyses of 31 fungal genomes (12 generated for this study) suggest that lignin-degrading peroxidases expanded in the lineage leading to the ancestor of the Agaricomycetes, which is reconstructed as a white rot species, and then contracted in parallel lineages leading to brown rot and mycorrhizal species. Molecular clock analyses suggest that the origin of lignin degradation might have coincided with the sharp decrease in the rate of organic carbon burial around the end of the Carboniferous period.

The role of effectors and host immunity in plant-necrotrophic fungal interactions.

PubMed

Wang, Xuli; Jiang, Nan; Liu, Jinling; Liu, Wende; Wang, Guo-Liang

2014-01-01

Fungal diseases pose constant threats to the global economy and food safety. As the largest group of plant fungal pathogens, necrotrophic fungi cause heavy crop losses worldwide. The molecular mechanisms of the interaction between necrotrophic fungi and plants are complex and involve sophisticated recognition and signaling networks. Here, we review recent findings on the roles of phytotoxin and proteinaceous effectors, pathogen-associated molecular patterns (PAMPs), and small RNAs from necrotrophic fungi. We also consider the functions of damage-associated molecular patterns (DAMPs), the receptor-like protein kinase BIK1, and epigenetic regulation in plant immunity to necrotrophic fungi.

Host pathogen relations: exploring animal models for fungal pathogens.

PubMed

Harwood, Catherine G; Rao, Reeta P

2014-06-30

Pathogenic fungi cause superficial infections but pose a significant public health risk when infections spread to deeper tissues, such as the lung. Within the last three decades, fungi have been identified as the leading cause of nosocomial infections making them the focus of research. This review outlines the model systems such as the mouse, zebrafish larvae, flies, and nematodes, as well as ex vivo and in vitro systems available to study common fungal pathogens.

Inactivation of a Pleurotus ostreatus versatile peroxidase-encoding gene (mnp2) results in reduced lignin degradation.

PubMed

Salame, Tomer M; Knop, Doriv; Levinson, Dana; Mabjeesh, Sameer J; Yarden, Oded; Hadar, Yitzhak

2014-01-01

Lignin biodegradation by white-rot fungi is pivotal to the earth's carbon cycle. Manganese peroxidases (MnPs), the most common extracellular ligninolytic peroxidases produced by white-rot fungi, are considered key in ligninolysis. Pleurotus ostreatus, the oyster mushroom, is a preferential lignin degrader occupying niches rich in lignocellulose such as decaying trees. Here, we provide direct, genetically based proof for the functional significance of MnP to P. ostreatus ligninolytic capacity under conditions mimicking its natural habitat. When grown on a natural lignocellulosic substrate of cotton stalks under solid-state culture conditions, gene and isoenzyme expression profiles of its short MnP and versatile peroxidase (VP)-encoding gene family revealed that mnp2 was predominately expressed. mnp2, encoding the versatile short MnP isoenzyme 2 was disrupted. Inactivation of mnp2 resulted in three interrelated phenotypes, relative to the wild-type strain: (i) reduction of 14% and 36% in lignin mineralization of stalks non-amended and amended with Mn(2+), respectively; (ii) marked reduction of the bioconverted lignocellulose sensitivity to subsequent bacterial hydrolyses; and (iii) decrease in fungal respiration rate. These results may serve as the basis to clarify the roles of the various types of fungal MnPs and VPs in their contribution to white-rot decay of wood and lignocellulose in various ecosystems. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

Edge effects on moisture reduce wood decomposition rate in a temperate forest.

PubMed

Crockatt, Martha E; Bebber, Daniel P

2015-02-01

Forests around the world are increasingly fragmented, and edge effects on forest microclimates have the potential to affect ecosystem functions such as carbon and nutrient cycling. Edges tend to be drier and warmer due to the effects of insolation, wind, and evapotranspiration and these gradients can penetrate hundreds of metres into the forest. Litter decomposition is a key component of the carbon cycle, which is largely controlled by saprotrophic fungi that respond to variation in temperature and moisture. However, the impact of forest fragmentation on litter decay is poorly understood. Here, we investigate edge effects on the decay of wood in a temperate forest using an experimental approach, whereby mass loss in wood blocks placed along 100 m transects from the forest edge to core was monitored over 2 years. Decomposition rate increased with distance from the edge, and was correlated with increasing humidity and moisture content of the decaying wood, such that the decay constant at 100 m was nearly twice that at the edge. Mean air temperature decreased slightly with distance from the edge. The variation in decay constant due to edge effects was larger than that expected from any reasonable estimates of climatic variation, based on a published regional model. We modelled the influence of edge effects on the decay constant at the landscape scale using functions for forest area within different distances from edge across the UK. We found that taking edge effects into account would decrease the decay rate by nearly one quarter, compared with estimates that assumed no edge effect. © 2014 John Wiley & Sons Ltd.

Fungal and Parasitic Infections of the Eye

PubMed Central

Klotz, Stephen A.; Penn, Christopher C.; Negvesky, Gerald J.; Butrus, Salim I.

2000-01-01

The unique structure of the human eye as well as exposure of the eye directly to the environment renders it vulnerable to a number of uncommon infectious diseases caused by fungi and parasites. Host defenses directed against these microorganisms, once anatomical barriers are breached, are often insufficient to prevent loss of vision. Therefore, the timely identification and treatment of the involved microorganisms are paramount. The anatomy of the eye and its surrounding structures is presented with an emphasis upon the association of the anatomy with specific infection of fungi and parasites. For example, filamentous fungal infections of the eye are usually due to penetrating trauma by objects contaminated by vegetable matter of the cornea or globe or, by extension, of infection from adjacent paranasal sinuses. Fungal endophthalmitis and chorioretinitis, on the other hand, are usually the result of antecedent fungemia seeding the ocular tissue. Candida spp. are the most common cause of endogenous endophthalmitis, although initial infection with the dimorphic fungi may lead to infection and scarring of the chorioretina. Contact lens wear is associated with keratitis caused by yeasts, filamentous fungi, and Acanthamoebae spp. Most parasitic infections of the eye, however, arise following bloodborne carriage of the microorganism to the eye or adjacent structures. PMID:11023963

Saprobe fungi decreased the sensitivity to the toxic effect of dry olive mill residue on arbuscular mycorrhizal plants.

PubMed

Sampedro, I; Aranda, E; Díaz, R; García-Sanchez, M; Ocampo, J A; García-Romera, I

2008-02-01

We studied the influence of olive mill dry residue (DOR) treated with saprobe fungi on growth of tomato and alfalfa colonized by Glomus deserticola. The application of 25g kg(-1) of dry DOR to soil decreased the shoot and root dry weight of tomato and alfalfa. Plants were more sensitive to the toxicity of DOR when colonized with the arbuscular mycorrhizal (AM) fungi. The sensitivity of both plants to the toxicity of DOR differed according to whether they were colonized by G. deserticola or by indigenous AM fungi. The phytotoxicity of DOR towards tomato and alfalfa was decreased by incubation the residue before planting with saprobe fungi for 20wk. The beneficial effects of AM fungi on plant growth added with DOR incubated with saprobe fungi depend of the type of the plant and AM fungi. The contribution of AM fungi to the beneficial effect of DOR incubated with saprobe fungi varied according to the type of the plant and AM fungi. G. deserticola increased the shoot and root dry weight of plants when they were grown in the presence of DOR incubated with saprobe fungi for 20wk. The beneficial effect of saprobe fungi on the dry weight and the level of AM mycorrhization of plants seem to be related to the decrease caused by these fungi in the phenol concentration in DOR. However, the toxicity of DOR due to substances other than phenols can not be ignored. The use of certain saprobe and AM fungi allows the possibility of using DOR as an organic fertilizer.

Fungal colonization and decomposition of leaves and stems of Salix arctica on deglaciated moraines in high-Arctic Canada

NASA Astrophysics Data System (ADS)

Osono, Takashi; Matsuoka, Shunsuke; Hirose, Dai; Uchida, Masaki; Kanda, Hiroshi

2014-06-01

Fungal colonization, succession, and decomposition of leaves and stems of Salix arctica were studied to estimate the roles of fungi in the decomposition processes in the high Arctic. The samples were collected from five moraines with different periods of development since deglaciation to investigate the effects of ecosystem development on the decomposition processes during the primary succession. The total hyphal lengths and the length of darkly pigmented hyphae increased during decomposition of leaves and stems and were not varied with the moraines. Four fungal morphotaxa were frequently isolated from both leaves and stems. The frequencies of occurrence of two morphotaxa varied with the decay class of leaves and/or stems. The hyphal lengths and the frequencies of occurrence of fungal morphotaxa were positively or negatively correlated with the contents of organic chemical components and nutrients in leaves and stems, suggesting the roles of fungi in chemical changes in the field. Pure culture decomposition tests demonstrated that the fungal morphotaxa were cellulose decomposers. Our results suggest that fungi took part in the chemical changes in decomposing leaves and stems even under the harsh environment of the high Arctic.

Antifungal efficacy of thymol, carvacrol, eugenol and menthol as alternative agents to control the growth of food-relevant fungi.

PubMed

Abbaszadeh, S; Sharifzadeh, A; Shokri, H; Khosravi, A R; Abbaszadeh, A

2014-06-01

This work is an attempt to examine the antifungal activity of thymol, carvacrol, eugenol and menthol against 11 food-decaying fungi. The susceptibility test for the compounds was carried out in terms of minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) using microdilution method in 96 multi-well microtiter plates. Results indicated that all compounds were effective to varying extents against various fungal isolates, with the highest efficacy displayed by carvacrol (mean MIC value: 154.5 μg/mL) (P<0.05). The incorporation of increased concentrations of all compounds to the media led to progressive and significant reduction in growth for all fungi. The most potent inhibitory activity of thymol, carvacrol, eugenol and menthol was found for Cladosporium spp. (MIC: 100 μg/mL), Aspergillus spp. (MIC: 100 μg/mL), Cladosporium spp. (MIC: 350 μg/mL), and Aspergillus spp. and Cladosporium spp. (MIC: 125 μg/mL), respectively. Thus, the application of these herbal components could be considered as a good alternatives to inhibit fungal growth and to reduce the use of synthetic fungicides. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Mycotic cysts: report of 21 cases including eight pheomycotic cysts from Saudi Arabia.

PubMed

Sheikh, Salwa S; Amr, Samir S

2007-04-01

Mycotic cysts are subcutaneous cystic granulomas caused by either dematiaceous (pigmented) fungi (pheomycotic cysts) or eumycotic (nonpigmented fungi) present in soil, wood, and decaying plant material. These fungi gain access to the tissues via a wooden splinter or thorn. No deep tissue involvement or extension to bone is known to occur. We reviewed our surgical pathology files for the last 32 years. All cases with the diagnosis of cysts with fungi, thorns, or splinters and associated granulomatous and acute inflammation were reviewed. Gomori's silver and periodic acid-Schiff stains were performed in all cases. Twenty-one cases of mycotic cyst were found, including eight pheomycotic cysts (one with a recurrent lesion seen 11 months after the initial excision of the cyst). Thirteen cysts had nonpigmented fungal hyphae. There were 14 males and seven females, with an age range of 5-76 years. The dorsum of the foot was the most frequently affected site (12 cases). Four cases involved the fingers, two involved the knee area, two involved the big toe, and one each involved the leg, ankle, and forearm. The cysts measured 0.6-4.5 cm in diameter. Histologically, there was granulomatous inflammation with a variable degree of neutrophilic infiltrate giving central abscess formation. Twelve cases showed a wooden splinter. All cases were positive for fungal organisms, mostly septate hyphae and spores that were highlighted by special stains. Fungal pigment, ranging from yellow-brown to light brown to black, was observed in eight cases. No extension to deep tissues was noted. The clinical impression varied widely including ganglion, sebaceous cyst, giant cell tumor of the tendon sheath, and lipoma. One patient was immunosuppressed following renal transplantation. All patients were treated by simple excision. No antifungal chemotherapy was needed or administered in any of the patients. One patient had a recurrence of his lesion within 1 year as a result of inadequate initial excision. A second re-excision was curative. Mycotic cysts are uncommonly encountered lesions that can be easily missed, especially in cases with scant fungal elements, thus requiring special stains to detect the organisms. We reported 21 cases of mycotic cyst, including eight pheomycotic cysts, with emphasis on the histopathologic recognition of this unusual entity.

Fungal biodegradation and enzymatic modification of lignin

PubMed Central

Dashtban, Mehdi; Schraft, Heidi; Syed, Tarannum A.; Qin, Wensheng

2010-01-01

Lignin, the most abundant aromatic biopolymer on Earth, is extremely recalcitrant to degradation. By linking to both hemicellulose and cellulose, it creates a barrier to any solutions or enzymes and prevents the penetration of lignocellulolytic enzymes into the interior lignocellulosic structure. Some basidiomycetes white-rot fungi are able to degrade lignin efficiently using a combination of extracellular ligninolytic enzymes, organic acids, mediators and accessory enzymes. This review describes ligninolytic enzyme families produced by these fungi that are involved in wood decay processes, their molecular structures, biochemical properties and the mechanisms of action which render them attractive candidates in biotechnological applications. These enzymes include phenol oxidase (laccase) and heme peroxidases [lignin peroxidase (LiP), manganese peroxidase (MnP) and versatile peroxidase (VP)]. Accessory enzymes such as H2O2-generating oxidases and degradation mechanisms of plant cell-wall components in a non-enzymatic manner by production of free hydroxyl radicals (·OH) are also discussed. PMID:21968746

An enigmatic fossil fungus from the 410 Ma Rhynie chert that resembles Macrochytrium (Chytridiomycota) and Blastocladiella (Blastocladiomycota).

PubMed

Krings, Michael; Taylor, Thomas N; Martin, Helmut

2016-01-01

Litter layers in the Lower Devonian (~ 410 Ma) Rhynie chert were inhabited by a wide variety of saprotrophic fungi, however, only a few of these organisms have been described formally. A new microfungus, Trewinomyces annulifer gen. et sp. nov., occurs as tufts on decaying land plant axes from the Rhynie chert. The fungus consists of an intramatrical rhizoidal system and an erect extramatrical hypha (stalk) that bears a single, terminal sporangium. One or two successive rings often are present in the stalk immediately below the sporangium base. Overall morphology of T. annulifer resembles the extant genera Macrochytrium (Chytridiomycota) and Blastocladiella (Blastocladiomycota). However, the rhizoids are septate or pseudoseptate, a feature not known in extant zoosporic fungi, and thus render the systematic affinities of T. annulifer unresolved. Trewinomyces annulifer offers a rare view of the morphology of a distinctive Early Devonian saprotrophic microfungus. © 2016 by The Mycological Society of America.

Rural Latino Immigrant Caregivers’ Conceptions of Their Children’s Oral Disease

PubMed Central

Horton, Sarah; Barker, Judith C.

2012-01-01

Objective To examine Latino immigrant caregivers’ explanatory models of the causes of early childhood caries (ECC). Methods In a rural area, we conducted 71 open-ended qualitative interviews with 26 Mexican immigrant and 12 Salvadoran immigrant caregivers of children under six about the causes of ECC. Two researchers independently read each interview and classified each interviewee’s response. Results Caregivers mentioned three biomedical causes of oral disease (sweets, poor oral hygiene, and bottle-feeding) and two lay or popular causes (lack of milk consumption and “bad” genes). Although caregivers were aware that the consumption of sweet foods causes decay, they expressed particular confusion about how bottle-feeding causes decay. Nineteen caregivers attributed decay specifically to bottle-feeding, yet 14 believed the cause of decay was the bottle’s nipple. Seven Mexican immigrant caregivers attributed their children’s decay specifically to a lack of calcium, and six immigrant caregivers to “bad teeth genes.” Conclusions Conceptions of oral disease derived from caregivers’ own dental experiences, their conceptions of the body, and interactions with dental professionals. The fact that biomedical explanations dominate the list of causes of caries for both groups indicates that caregivers’ explanatory models of oral disease are powerfully shaped by interactions with health professionals. Immigrant caregivers’ mistaking of the baby bottle’s nipple as the source of decay indicates the need for more effective oral health promotion. Yet Mexican immigrants’ conceptions of a lack of calcium as a major factor in their children’s decay may illustrate a strong cultural link between teeth and milk. PMID:18248338

Rural Latino immigrant caregivers' conceptions of their children's oral disease.

PubMed

Horton, Sarah; Barker, Judith C

2008-01-01

The aim of this study was to examine Latino immigrant caregivers' explanatory models of the causes of early childhood caries (ECC). In a rural area, we conducted 71 open-ended qualitative interviews with 26 Mexican immigrant and 12 Salvadoran immigrant caregivers of children under 6 about the causes of ECC. Two researchers independently read each interview and classified each interviewee's response. Caregivers mentioned three biomedical causes of oral disease (sweets, poor oral hygiene, and bottle-feeding) and two lay or popular causes (lack of milk consumption and "bad" genes). Although caregivers were aware that the consumption of sweet foods causes decay they expressed particular confusion about how bottle-feeding causes decay. Nineteen caregivers attributed decay specifically to bottle-feeding, yet 14 believed the cause of decay was the bottle's nipple. Seven Mexican immigrant caregivers attributed their children's decay specifically to a lack of calcium, and six immigrant caregivers to "bad teeth genes." Conceptions of oral disease derived from the caregivers' own dental experiences, their conceptions of the body, and interactions with dental professionals. The fact that biomedical explanations dominate the list of causes of caries for both groups indicates that the caregivers' explanatory models of oral disease are powerfully shaped by interactions with health professionals. Immigrant caregivers' mistaking of the baby bottle's nipple as the source of decay indicates the need for more effective oral health promotion. Yet the Mexican immigrants' conceptions of a lack of calcium as a major factor in their children's decay may illustrate a strong cultural link between teeth and milk.

Occurrence and hygienic relevance of fungi in drinking water.

PubMed

Kanzler, D; Buzina, W; Paulitsch, A; Haas, D; Platzer, S; Marth, E; Mascher, F

2008-03-01

Fungi, above all filamentous fungi, can occur almost everywhere, even in water. They can grow in such a quantity in water that they can affect the health of the population or have negative effects on food production. There are several reports of fungal growth in water from different countries, but to our knowledge none from Austria so far. The aim of this study was to gain an overview of the spectrum of filamentous fungi and yeasts in drinking water systems. Thirty-eight water samples from drinking water and groundwater were analysed. Fungi were isolated by using membrane filtration and plating method with subsequent cultivation on agar plates. The different taxa of fungi were identified using routine techniques as well as molecular methods. Fungi were isolated in all water samples examined. The mean value for drinking water was 9.1 CFU per 100 ml and for groundwater 5400 CFU per 100 ml. Altogether 32 different taxa of fungi were found. The taxa which occurred most frequently were Cladosporium spp., Basidiomycetes and Penicillium spp. (74.6%, 56.4% and 48.7%, respectively). This study shows that drinking water can be a reservoir for fungi, among them opportunists, which can cause infections in immunosuppressed patients.

Maxillary Sinusitis Caused by Actinomucor elegans

PubMed Central

Davel, Graciela; Featherston, Patricia; Fernández, Anibal; Abrantes, Ruben; Canteros, Cristina; Rodero, Laura; Sztern, Carlos; Perrotta, Diego

2001-01-01

We report the first case of maxillary sinusitis caused by Actinomucor elegans in an 11-year-old patient. Histopathological and mycological examinations of surgical maxillary sinuses samples showed coenocytic hyphae characteristic of mucoraceous fungi. The fungi recovered had stolons and rhizoids, nonapophyseal and globose sporangia, and whorled branched sporangiophores and was identified as A. elegans. After surgical cleaning and chemotherapy with amphotericin B administered intravenously and by irrigation, the patient became asymptomatic and the mycological study results were negative. PMID:11158140

Analysis of Canadian and Irish forage, oats and commercially available equine concentrate feed for pathogenic fungi and mycotoxins

PubMed Central

2007-01-01

Respiratory infections, recurrent airway obstruction (RAO) and exercise induced pulmonary haemorrhage (EIPH) are major causes of poor performance in horses. Fungi and mycotoxins are now recognised as a major cause of these conditions. The most notable fungi are Aspergillus and Fusarium. Fungal spores can originate from forage, bedding and feed and, in turn, these fungal spores can produce a series of mycotoxins as secondary metabolites. This study set out to ascertain the degree of fungal and mycotoxin contamination in feed and fodder used in Irish racing yards over a one-year period. Weather conditions in forage producing areas were sampled by Met Eireann and the Canadian Meteorological Service. Fifty per cent of Irish hay, 37% of haylage and 13% of Canadian hay contained pathogenic fungi. Of the mycotoxins, T2 and zearalenone were most prominent. Twenty-one per cent of Irish hay and 16% of pelleted feed contained zearalenone. Forty per cent of oats and 54% of pelleted feed contained T2 toxins. PMID:21851693

The vaginal mycobiome: A contemporary perspective on fungi in women's health and diseases.

PubMed

Bradford, L Latéy; Ravel, Jacques

2017-04-03

Most of what is known about fungi in the human vagina has come from culture-based studies and phenotypic characterization of single organisms. Though valuable, these approaches have masked the complexity of fungal communities within the vagina. The vaginal mycobiome has become an emerging field of study as genomics tools are increasingly employed and we begin to appreciate the role these fungal communities play in human health and disease. Though vastly outnumbered by its bacterial counterparts, fungi are important constituents of the vaginal ecosystem in many healthy women. Candida albicans, an opportunistic fungal pathogen, colonizes 20% of women without causing any overt symptoms, yet it is one of the leading causes of infectious vaginitis. Understanding its mechanisms of commensalism and patho-genesis are both essential to developing more effective therapies. Describing the interactions between Candida, bacteria (such as Lactobacillus spp.) and other fungi in the vagina is funda-mental to our characterization of the vaginal mycobiome.

Developments in Fungal Taxonomy

PubMed Central

Guarro, Josep; Gené, Josepa; Stchigel, Alberto M.

1999-01-01

Fungal infections, especially those caused by opportunistic species, have become substantially more common in recent decades. Numerous species cause human infections, and several new human pathogens are discovered yearly. This situation has created an increasing interest in fungal taxonomy and has led to the development of new methods and approaches to fungal biosystematics which have promoted important practical advances in identification procedures. However, the significance of some data provided by the new approaches is still unclear, and results drawn from such studies may even increase nomenclatural confusion. Analyses of rRNA and rDNA sequences constitute an important complement of the morphological criteria needed to allow clinical fungi to be more easily identified and placed on a single phylogenetic tree. Most of the pathogenic fungi so far described belong to the kingdom Fungi; two belong to the kingdom Chromista. Within the Fungi, they are distributed in three phyla and in 15 orders (Pneumocystidales, Saccharomycetales, Dothideales, Sordariales, Onygenales, Eurotiales, Hypocreales, Ophiostomatales, Microascales, Tremellales, Poriales, Stereales, Agaricales, Schizophyllales, and Ustilaginales). PMID:10398676

The vaginal mycobiome: A contemporary perspective on fungi in women's health and diseases

PubMed Central

2017-01-01

ABSTRACT Most of what is known about fungi in the human vagina has come from culture-based studies and phenotypic characterization of single organisms. Though valuable, these approaches have masked the complexity of fungal communities within the vagina. The vaginal mycobiome has become an emerging field of study as genomics tools are increasingly employed and we begin to appreciate the role these fungal communities play in human health and disease. Though vastly outnumbered by its bacterial counterparts, fungi are important constituents of the vaginal ecosystem in many healthy women. Candida albicans, an opportunistic fungal pathogen, colonizes 20% of women without causing any overt symptoms, yet it is one of the leading causes of infectious vaginitis. Understanding its mechanisms of commensalism and patho-genesis are both essential to developing more effective therapies. Describing the interactions between Candida, bacteria (such as Lactobacillus spp.) and other fungi in the vagina is funda-mental to our characterization of the vaginal mycobiome. PMID:27657355

Analysis of Canadian and Irish forage, oats and commercially available equine concentrate feed for pathogenic fungi and mycotoxins.

PubMed

Buckley, Thomas; Creighton, Alan; Fogarty, Ursula

2007-04-01

Respiratory infections, recurrent airway obstruction (RAO) and exercise induced pulmonary haemorrhage (EIPH) are major causes of poor performance in horses. Fungi and mycotoxins are now recognised as a major cause of these conditions. The most notable fungi are Aspergillus and Fusarium. Fungal spores can originate from forage, bedding and feed and, in turn, these fungal spores can produce a series of mycotoxins as secondary metabolites.This study set out to ascertain the degree of fungal and mycotoxin contamination in feed and fodder used in Irish racing yards over a one-year period. Weather conditions in forage producing areas were sampled by Met Eireann and the Canadian Meteorological Service.Fifty per cent of Irish hay, 37% of haylage and 13% of Canadian hay contained pathogenic fungi. Of the mycotoxins, T2 and zearalenone were most prominent. Twenty-one per cent of Irish hay and 16% of pelleted feed contained zearalenone. Forty per cent of oats and 54% of pelleted feed contained T2 toxins.

Whole-cell biosensor of cellobiose and application to wood decay detection.

PubMed

Toussaint, Maxime; Bontemps, Cyril; Besserer, Arnaud; Hotel, Laurence; Gérardin, Philippe; Leblond, Pierre

2016-12-10

Fungal biodegradation of wood is one of the main threats regarding its use as a material. So far, the detection of this decaying process is empirically assessed by loss of mass, when the fungal attack is advanced and woody structure already damaged. Being able to detect fungal attack on wood in earlier steps is thus of special interest for the wood economy. In this aim, we designed here a new diagnostic tool for wood degradation detection based on the bacterial whole-cell biosensor technology. It was designed in diverting the soil bacteria Streptomyces CebR sensor system devoted to cellobiose detection, a cellulolytic degradation by-product emitted by lignolytic fungi since the onset of wood decaying process. The conserved regulation scheme of the CebR system among Streptomyces allowed constructing a molecular tool easily transferable in different strains or species and enabling the screen for optimal host strains for cellobiose detection. Assays are performed in microplates using one-day culture lysates. Diagnostic is performed within one hour by a spectrophotometric measuring of the cathecol deshydrogenase activity. The selected biosensor was able to detect specifically cellobiose at concentrations similar to those measured in decaying wood and in a spruce leachate attacked by a lignolytic fungus, indicating a high potential of applicability to detect ongoing wood decay process. Copyright © 2016 Elsevier B.V. All rights reserved.

Response of nematode-trapping fungi to organic substrates in a coastal grassland soil.

PubMed

Nguyen, Vi L; Bastow, Justin L; Jaffee, Bruce A; Strong, Don R

2007-07-01

To understand why Arthrobotrys oligospora and other nematode-trapping fungi are common and sometimes abundant in the coastal grassland soils of the Bodega Marine Reserve (BMR, Sonoma County, CA), we examined how resident trapping fungi responded to the addition of eight organic substrates (lupine leaves, grass leaves, dead isopods, dead moth larvae, isopod faeces, deer faeces, shrimp shells, and powdered chitin). We were especially interested in the effects of dead isopods because isopods are abundant at BMR and because previous studies had documented strong responses of A. oligospora to other arthropods (dead moth larvae). Soil from BMR was packed into vials (40 g dry mass equivalent per vial with water potential at -230 kPa and bulk density at 0.9 gcm(-3)), and one substrate or no substrate was added to the soil surface. After 30 d at 20 degrees C, trapping fungi were quantified by dilution plating and most probable number procedures. The response of A. oligospora was inversely related to substrate carbon:nitrogen (C:N) ratio: substrates with low C:N ratios (dead isopods, lupine leaves, dead moth larvae) usually caused large increases in A. oligospora whereas those with higher C:N ratios (isopod faeces, deer faeces, grass leaves) did not. An exception was chitin powder, which had a low C:N ratio, but which did not cause A. oligospora to proliferate. Responses of A. oligospora were directly related to the quantity of nitrogen added with each substrate, and those substrates that caused large increases in resident nematodes usually caused large increases in A. oligospora. Other trapping fungi did not respond as strongly as A. oligospora.

Clash of kingdoms or why Drosophila larvae positively respond to fungal competitors.

PubMed

Rohlfs, Marko

2005-01-27

BACKGROUND: Competition with filamentous fungi has been demonstrated to be an important cause of mortality for the vast group of insects that depend on ephemeral resources (e.g. fruit, dung, carrion). Recent data suggest that the well-known aggregation of Drosophila larvae across decaying fruit yields a competitive advantage over mould, by which the larvae achieve a higher survival probability in larger groups compared with smaller ones. Feeding and locomotor behaviour of larger larval groups is assumed to cause disruption of fungal hyphae, leading to suppression of fungal growth, which in turn improves the chances of larval survival to the adult stage. Given the relationship between larval density, mould suppression and larval survival, the present study has tested whether fungal-infected food patches elicit communal foraging behaviour on mould-infected sites by which larvae might hamper mould growth more efficiently. RESULTS: Based on laboratory experiments in which Drosophila larvae were offered the choice between fungal-infected and uninfected food patches, larvae significantly aggregated on patches containing young fungal colonies. Grouping behaviour was also visible when larvae were offered only fungal-infected or only uninfected patches; however, larval aggregation was less strong under these conditions than in a heterogeneous environment (infected and uninfected patches). CONCLUSION: Because filamentous fungi can be deadly competitors for insect larvae on ephemeral resources, social attraction of Drosophila larvae to fungal-infected sites leading to suppression of mould growth may reflect an adaptive behavioural response that increases insect larval fitness and can thus be discussed as an anti-competitor behaviour. These observations support the hypothesis that adverse environmental conditions operate in favour of social behaviour. In a search for the underlying mechanisms of communal behaviour in Drosophila, this study highlights the necessity of investigating the role of inter-kingdom competition as a potential driving force in the evolution of spatial behaviour in insects.

Delayed fungal evolution did not cause the Paleozoic peak in coal production.

PubMed

Nelsen, Matthew P; DiMichele, William A; Peters, Shanan E; Boyce, C Kevin

2016-03-01

Organic carbon burial plays a critical role in Earth systems, influencing atmospheric O2 and CO2 concentrations and, thereby, climate. The Carboniferous Period of the Paleozoic is so named for massive, widespread coal deposits. A widely accepted explanation for this peak in coal production is a temporal lag between the evolution of abundant lignin production in woody plants and the subsequent evolution of lignin-degrading Agaricomycetes fungi, resulting in a period when vast amounts of lignin-rich plant material accumulated. Here, we reject this evolutionary lag hypothesis, based on assessment of phylogenomic, geochemical, paleontological, and stratigraphic evidence. Lignin-degrading Agaricomycetes may have been present before the Carboniferous, and lignin degradation was likely never restricted to them and their class II peroxidases, because lignin modification is known to occur via other enzymatic mechanisms in other fungal and bacterial lineages. Furthermore, a large proportion of Carboniferous coal horizons are dominated by unlignified lycopsid periderm with equivalent coal accumulation rates continuing through several transitions between floral dominance by lignin-poor lycopsids and lignin-rich tree ferns and seed plants. Thus, biochemical composition had little relevance to coal accumulation. Throughout the fossil record, evidence of decay is pervasive in all organic matter exposed subaerially during deposition, and high coal accumulation rates have continued to the present wherever environmental conditions permit. Rather than a consequence of a temporal decoupling of evolutionary innovations between fungi and plants, Paleozoic coal abundance was likely the result of a unique combination of everwet tropical conditions and extensive depositional systems during the assembly of Pangea.

Delayed fungal evolution did not cause the Paleozoic peak in coal production

PubMed Central

Nelsen, Matthew P.; DiMichele, William A.; Peters, Shanan E.; Boyce, C. Kevin

2016-01-01

Organic carbon burial plays a critical role in Earth systems, influencing atmospheric O2 and CO2 concentrations and, thereby, climate. The Carboniferous Period of the Paleozoic is so named for massive, widespread coal deposits. A widely accepted explanation for this peak in coal production is a temporal lag between the evolution of abundant lignin production in woody plants and the subsequent evolution of lignin-degrading Agaricomycetes fungi, resulting in a period when vast amounts of lignin-rich plant material accumulated. Here, we reject this evolutionary lag hypothesis, based on assessment of phylogenomic, geochemical, paleontological, and stratigraphic evidence. Lignin-degrading Agaricomycetes may have been present before the Carboniferous, and lignin degradation was likely never restricted to them and their class II peroxidases, because lignin modification is known to occur via other enzymatic mechanisms in other fungal and bacterial lineages. Furthermore, a large proportion of Carboniferous coal horizons are dominated by unlignified lycopsid periderm with equivalent coal accumulation rates continuing through several transitions between floral dominance by lignin-poor lycopsids and lignin-rich tree ferns and seed plants. Thus, biochemical composition had little relevance to coal accumulation. Throughout the fossil record, evidence of decay is pervasive in all organic matter exposed subaerially during deposition, and high coal accumulation rates have continued to the present wherever environmental conditions permit. Rather than a consequence of a temporal decoupling of evolutionary innovations between fungi and plants, Paleozoic coal abundance was likely the result of a unique combination of everwet tropical conditions and extensive depositional systems during the assembly of Pangea. PMID:26787881

The role of effectors and host immunity in plant–necrotrophic fungal interactions

PubMed Central

Wang, Xuli; Jiang, Nan; Liu, Jinling; Liu, Wende; Wang, Guo-Liang

2014-01-01

Fungal diseases pose constant threats to the global economy and food safety. As the largest group of plant fungal pathogens, necrotrophic fungi cause heavy crop losses worldwide. The molecular mechanisms of the interaction between necrotrophic fungi and plants are complex and involve sophisticated recognition and signaling networks. Here, we review recent findings on the roles of phytotoxin and proteinaceous effectors, pathogen-associated molecular patterns (PAMPs), and small RNAs from necrotrophic fungi. We also consider the functions of damage-associated molecular patterns (DAMPs), the receptor-like protein kinase BIK1, and epigenetic regulation in plant immunity to necrotrophic fungi. PMID:25513773

Tools of the crook – infection strategies of fungal plant pathogens

USDA-ARS?s Scientific Manuscript database

Fungi represent an ecologically diverse group of microorganisms that includes plant pathogenic species able to cause considerable yield loses in crop production systems worldwide. In order to establish compatible interactions with their hosts, pathogenic fungi rely on the secretion of molecules of d...

Putative rust fungal effector proteins in infected bean and soybean leaves

USDA-ARS?s Scientific Manuscript database

The plant pathogenic fungi Uromyces appendiculatus and Phakopsora pachyrhizi cause debilitating rust diseases on common bean and soybean. These rust fungi secrete effector proteins that allow them to infect plants, but the effector repertoire for U. appendiculatus and P. pachyrhizi is not fully def...

An Antifungal Role of Hydrogen Sulfide on the Postharvest Pathogens Aspergillus niger and Penicillium italicum

PubMed Central

Li, Yan-Hong; Hu, Liang-Bin; Yan, Hong; Liu, Yong-Sheng; Zhang, Hua

2014-01-01

In this research, the antifungal role of hydrogen sulfide (H2S) on the postharvest pathogens Aspergillus niger and Penicillium italicum growing on fruits and under culture conditions on defined media was investigated. Our results show that H2S, released by sodium hydrosulfide (NaHS) effectively reduced the postharvest decay of fruits induced by A. niger and P. italicum. Furthermore, H2S inhibited spore germination, germ tube elongation, mycelial growth, and produced abnormal mycelial contractions when the fungi were grown on defined media in Petri plates. Further studies showed that H2S could cause an increase in intracellular reactive oxygen species (ROS) in A. niger. In accordance with this observation we show that enzyme activities and the expression of superoxide dismutase (SOD) and catalase (CAT) genes in A. niger treated with H2S were lower than those in control. Moreover, H2S also significantly inhibited the growth of Saccharomyces cerevisiae, Rhizopus oryzae, the human pathogen Candida albicans, and several food-borne bacteria. We also found that short time exposure of H2S showed a microbicidal role rather than just inhibiting the growth of microbes. Taken together, this study suggests the potential value of H2S in reducing postharvest loss and food spoilage caused by microbe propagation. PMID:25101960

Characterization and pathogenicity of Fusarium species associated with leaf spot of mango (Mangifera indica L.).

PubMed

Omar, Nurul Husna; Mohd, Masratulhawa; Mohamed Nor, Nik Mohd Izham; Zakaria, Latiffah

2018-01-01

Leaf spot diseases are mainly caused by fungi including Fusarium. In the present study several species of Fusarium were isolated from the leaf spot lesion of mango (Mangifera indica L.) Based on morphological characteristics, TEF-1α sequences and phylogenetic analysis, five species were identified as F. proliferatum, F. semitectum, F. mangiferae, F. solani and F. chlamydosporum. Pathogenicity test indicated that representative isolates of F. proliferatum, F. semitectum and F. chlamydosporum were pathogenic on mango leaves causing leaf spot with low to moderate virulence. Nevertheless, abundance of spots on the leaf can disrupt photosynthesis which in turn reduced growth, and lead to susceptibility to infection by opportunistic pathogens due to weakening of the plant. Fusarium solani and F. mangiferae were non-pathogenic and it is possible that both species are saprophyte which associated with nutrient availability on the surface of the leaf through decaying leave tissues. The occurrence of Fusarium spp. on the leaf spot lesion and the effect from the disease needs to be considered when developing disease management method of mango cultivation as numerous spot on the leaves could effect the photosynthesis process and finally giving low yield and less quality of mango. Copyright © 2017. Published by Elsevier Ltd.

The Paleozoic origin of enzymatic mechanisms for lignin degradation reconstructed using 31 fungal genomes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Floudas, Dimitrios; Binder, Manfred; Riley, Robert

Wood is a major pool of organic carbon that is highly resistant to decay, owing largely to the presence of lignin. The only organisms capable of substantial lignin decay are white rot fungi in the Agaricomycetes, which also contains non?lignin-degrading brown rot and ectomycorrhizal species. Comparative analyses of 31 fungal genomes (12 generated for this study) suggest that lignin-degrading peroxidases expanded in the lineage leading to the ancestor of the Agaricomycetes, which is reconstructed as a white rot species, and then contracted in parallel lineages leading to brown rot and mycorrhizal species. Molecular clock analyses suggest that the origin ofmore » lignin degradation might have coincided with the sharp decrease in the rate of organic carbon burial around the end of the Carboniferous period.« less

Insects as a Nitrogen Source for Plants

PubMed Central

Behie, Scott W.; Bidochka, Michael J.

2013-01-01

Many plants have evolved adaptations in order to survive in low nitrogen environments. One of the best-known adaptations is that of plant symbiosis with nitrogen-fixing bacteria; this is the major route by which nitrogen is incorporated into plant biomass. A portion of this plant-associated nitrogen is then lost to insects through herbivory, and insects represent a nitrogen reservoir that is generally overlooked in nitrogen cycles. In this review we show three specialized plant adaptations that allow for the recovery of insect nitrogen; that is, plants gaining nitrogen from insects. First, we show specialized adaptations by carnivorous plants in low nitrogen habitats. Insect carnivorous plants such as pitcher plants and sundews (Nepenthaceae/Sarraceniaceae and Drosera respectively) are able to obtain substantial amounts of nitrogen from the insects that they capture. Secondly, numerous plants form associations with mycorrhizal fungi that can provide soluble nitrogen from the soil, some of which may be insect-derived nitrogen, obtained from decaying insects or insect frass. Finally, a specialized group of endophytic, insect-pathogenic fungi (EIPF) provide host plants with insect-derived nitrogen. These soil-inhabiting fungi form a remarkable symbiosis with certain plant species. They can infect a wide range of insect hosts and also form endophytic associations in which they transfer insect-derived nitrogen to the plant. Root colonizing fungi are found in disparate fungal phylogenetic lineages, indicating possible convergent evolutionary strategies between taxa, evolution potentially driven by access to carbon-containing root exudates. PMID:26462427

Meningitis

MedlinePlus

... are caused by viruses ( viral meningitis ) or bacteria ( bacterial meningitis ). Fungi and other organisms can also cause infectious ... can spread through the body to cause meningitis. Bacterial meningitis is a more severe form of the infection. ...

Moldy buildings, health of their occupants and fungal prevention.

PubMed

Mihinova, D; Pieckova, E

2012-01-01

Microscopic fungi are important biological pollutants in the indoor environment, they are spread generally: on building materials, carpets, ceiling tiles, insulations, any surfaces, wallpapers, or in heating, ventilation, and air conditioning systems. Molds are able to grow on any materials, as long as moisture and oxygen are available. Exposure to fungi in indoor environments (esp. in water-damaged buildings) can cause adverse health effects, such as allergy, asthma, hypersensitivity pneumonia, mucous membrane irritation, different toxic effects, or even mycoses (in immunocompromised individuals) - alone or in combination. As serious adverse health effects could be caused antifungal prevention is an absolute need.This review article summarizes the occurrence of fungi in the indoor environment of buildings and their contribution to occupants´ health problems, and preventive measures against molds (Tab. 1, Fig. 1, Ref. 48).

Role of alternate hosts in epidemiology and pathogen variation of cereal rusts

USDA-ARS?s Scientific Manuscript database

Cereal rusts, caused by obligate and biotrophic fungi in the genus Puccinia of basidiomycete are an important group of diseases threatening the world food security. With the recent discovery of alternate hosts for the stripe rust fungus (Puccinia striiformis), all cereal rust fungi are now known ...

The microbial community in decaying fallen logs varies with critical period in an alpine forest.

PubMed

Chang, Chenhui; Wu, Fuzhong; Yang, Wanqin; Xu, Zhenfeng; Cao, Rui; He, Wei; Tan, Bo; Justine, Meta Francis

2017-01-01

Little information has been available on the shifts in the microbial community in decaying fallen logs during critical periods in cold forests. Minjiang fir (Abies faxoniana) fallen logs in decay classes I-V were in situ incubated on the forest floor of an alpine forest in the eastern Tibet Plateau. The microbial community was investigated during the seasonal snow cover period (SP), snow thawing period (TP), early growing season (EG) and late growing season (LG) using Phosphorous Lipid Fatty Acid (PLFA) analysis. Total microbial biomass and microbial diversity in fallen logs were much more affected by critical period than decay class, whereas decay class had a stronger effect on microbial diversity than on microbial biomass. Abundant microbial biomass and microbial diversity in logs even without the cover of snow were observed in winter, which could not be linked to thermal insulation by snow cover. The freshly decayed logs functioned as an excellent buffer of environmental variation for microbial organisms during the sharp fluctuations in temperature in winter. We also found distinct decay patterns along with seasonality for heartwood, sapwood and bark, which requires further detailed research. Gram- bacteria mainly dominated the shifts in microbial community composition from SP to EG, while fungi and Gram+ bacteria mainly dominated it from SP to TP. Based on previous work and the present study, we conclude that fallen logs on the forest floor alter ecological processes by influencing microbial communities on woody debris and beneath the soil and litter. Our study also emphasizes the need to maintain a number of fallen logs, especially fresh ones, on the forest floor.

The microbial community in decaying fallen logs varies with critical period in an alpine forest

PubMed Central

Chang, Chenhui; Wu, Fuzhong; Xu, Zhenfeng; Cao, Rui; He, Wei; Tan, Bo; Justine, Meta Francis

2017-01-01

Little information has been available on the shifts in the microbial community in decaying fallen logs during critical periods in cold forests. Minjiang fir (Abies faxoniana) fallen logs in decay classes I-V were in situ incubated on the forest floor of an alpine forest in the eastern Tibet Plateau. The microbial community was investigated during the seasonal snow cover period (SP), snow thawing period (TP), early growing season (EG) and late growing season (LG) using Phosphorous Lipid Fatty Acid (PLFA) analysis. Total microbial biomass and microbial diversity in fallen logs were much more affected by critical period than decay class, whereas decay class had a stronger effect on microbial diversity than on microbial biomass. Abundant microbial biomass and microbial diversity in logs even without the cover of snow were observed in winter, which could not be linked to thermal insulation by snow cover. The freshly decayed logs functioned as an excellent buffer of environmental variation for microbial organisms during the sharp fluctuations in temperature in winter. We also found distinct decay patterns along with seasonality for heartwood, sapwood and bark, which requires further detailed research. Gram- bacteria mainly dominated the shifts in microbial community composition from SP to EG, while fungi and Gram+ bacteria mainly dominated it from SP to TP. Based on previous work and the present study, we conclude that fallen logs on the forest floor alter ecological processes by influencing microbial communities on woody debris and beneath the soil and litter. Our study also emphasizes the need to maintain a number of fallen logs, especially fresh ones, on the forest floor. PMID:28787465

Assemblage composition of fungal wood-decay species has a major influence on how climate and wood quality modify decomposition.

PubMed

Venugopal, Parvathy; Junninen, Kaisa; Edman, Mattias; Kouki, Jari

2017-03-01

The interactions among saprotrophic fungal species, as well as their interactions with environmental factors, may have a major influence on wood decay and carbon release in ecosystems. We studied the effect that decomposer diversity (species richness and assemblage composition) has on wood decomposition when the climatic variables and substrate quality vary simultaneously. We used two temperatures (16 and 21°C) and two humidity levels (70% and 90%) with two wood qualities (wood from managed and old-growth forests) of Pinus sylvestris. In a 9-month experiment, the effects of fungal diversity were tested using four wood-decaying fungi (Antrodia xantha, Dichomitus squalens, Fomitopsis pinicola and Gloeophyllum protractum) at assemblage levels of one, two and four species. Wood quality and assemblage composition affected the influence of climatic factors on decomposition rates. Fungal assemblage composition was found to be more important than fungal species richness, indicating that species-specific fungal traits are of paramount importance in driving decomposition. We conclude that models containing fungal wood-decay species (and wood-based carbon) need to take into account species-specific and assemblage composition-specific properties to improve predictive capacity in regard to decomposition-related carbon dynamics. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Fast, reagentless and reliable screening of "white powders" during the bioterrorism hoaxes.

PubMed

Włodarski, Maksymilian; Kaliszewski, Miron; Trafny, Elżbieta Anna; Szpakowska, Małgorzata; Lewandowski, Rafał; Bombalska, Aneta; Kwaśny, Mirosław; Kopczyński, Krzysztof; Mularczyk-Oliwa, Monika

2015-03-01

The classification of dry powder samples is an important step in managing the consequences of terrorist incidents. Fluorescence decays of these samples (vegetative bacteria, bacterial endospores, fungi, albumins and several flours) were measured with stroboscopic technique using an EasyLife LS system PTI. Three pulsed nanosecond LED sources, generating 280, 340 and 460nm were employed for samples excitation. The usefulness of a new 460nm light source for fluorescence measurements of dry microbial cells has been demonstrated. The principal component analysis (PCA) and hierarchical cluster analysis (HCA) have been used for classification of dry biological samples. It showed that the single excitation wavelength was not sufficient for differentiation of biological samples of diverse origin. However, merging fluorescence decays from two or three excitation wavelengths allowed classification of these samples. An experimental setup allowing the practical implementation of this method for the real time fluorescence decay measurement was designed. It consisted of the LED emitting nanosecond pulses at 280nm and two fast photomultiplier tubes (PMTs) for signal detection in two fluorescence bands simultaneously. The positive results of the dry powder samples measurements confirmed that the fluorescence decay-based technique could be a useful tool for fast classification of the suspected "white powders" performed by the first responders. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Fungi from a Groundwater-Fed Drinking Water Supply System in Brazil

PubMed Central

Oliveira, Helena M.B.; Santos, Cledir; Paterson, R. Russell M.; Gusmão, Norma B.; Lima, Nelson

2016-01-01

Filamentous fungi in drinking water distribution systems are known to (a) block water pipes; (b) cause organoleptic biodeterioration; (c) act as pathogens or allergens and (d) cause mycotoxin contamination. Yeasts might also cause problems. This study describes the occurrence of several fungal species in a water distribution system supplied by groundwater in Recife—Pernambuco, Brazil. Water samples were collected from four sampling sites from which fungi were recovered by membrane filtration. The numbers in all sampling sites ranged from 5 to 207 colony forming units (CFU)/100 mL with a mean value of 53 CFU/100 mL. In total, 859 isolates were identified morphologically, with Aspergillus and Penicillium the most representative genera (37% and 25% respectively), followed by Trichoderma and Fusarium (9% each), Curvularia (5%) and finally the species Pestalotiopsis karstenii (2%). Ramichloridium and Leptodontium were isolated and are black yeasts, a group that include emergent pathogens. The drinking water system in Recife may play a role in fungal dissemination, including opportunistic pathogens. PMID:27005653

Fungi from a Groundwater-Fed Drinking Water Supply System in Brazil.

PubMed

Oliveira, Helena M B; Santos, Cledir; Paterson, R Russell M; Gusmão, Norma B; Lima, Nelson

2016-03-09

Filamentous fungi in drinking water distribution systems are known to (a) block water pipes; (b) cause organoleptic biodeterioration; (c) act as pathogens or allergens and (d) cause mycotoxin contamination. Yeasts might also cause problems. This study describes the occurrence of several fungal species in a water distribution system supplied by groundwater in Recife-Pernambuco, Brazil. Water samples were collected from four sampling sites from which fungi were recovered by membrane filtration. The numbers in all sampling sites ranged from 5 to 207 colony forming units (CFU)/100 mL with a mean value of 53 CFU/100 mL. In total, 859 isolates were identified morphologically, with Aspergillus and Penicillium the most representative genera (37% and 25% respectively), followed by Trichoderma and Fusarium (9% each), Curvularia (5%) and finally the species Pestalotiopsis karstenii (2%). Ramichloridium and Leptodontium were isolated and are black yeasts, a group that include emergent pathogens. The drinking water system in Recife may play a role in fungal dissemination, including opportunistic pathogens.

Effect of chitosan on hyphal growth and spore germination of plant pathogenic and biocontrol fungi.

PubMed

Palma-Guerrero, J; Jansson, H-B; Salinas, J; Lopez-Llorca, L V

2008-02-01

To investigate the toxic effect of chitosan on important root pathogenic and biocontrol fungi (nematophagous, entomopathogenic and mycoparasitic). We have used standard bioassays to investigate the effect of chitosan on colony growth and developed bioassays to test spore germination. The results showed that the root pathogenic and mycoparasitic fungi tested were more sensitive to chitosan than nematophagous and entomopathogenic fungi. Chitosanases (and perhaps related enzymes) are involved in the resistance to chitosan. Two fungi, one sensitive to chitosan, Fusarium oxysporum f. sp. radicis-lycopersici, and one less sensitive, Pochonia chlamydosporia, were selected for ultrastructural investigations. Transmission electron microscopy revealed differences in the ultrastructural alterations caused by chitosan in the spores of the plant pathogenic fungus and in those of the nematophagous fungus. Confocal laser microscopy showed that Rhodamine-labelled chitosan enters rapidly into conidia of both fungi, in an energy-dependent process. Nematophagous and entomopathogenic fungi are rather resistant to the toxic effect of chitosan. Resistance of nematophagous and entomopathogenic fungi to chitosan could be associated with their high extracellular chitosanolytic activity. Furthermore, ultrastructural damage is much more severe in the chitosan sensitive fungus. The results of this paper suggest that biocontrol fungi tested could be combined with chitosan for biological control of plant pathogens and pests.

Impact of abiotic factors on development of the community of arbuscular mycorrhizal fungi in the soil: a Review

NASA Astrophysics Data System (ADS)

Jamiołkowska, Agnieszka; Księżniak, Andrzej; Gałązka, Anna; Hetman, Beata; Kopacki, Marek; Skwaryło-Bednarz, Barbara

2018-01-01

Arbuscular mycorrhizal fungi inhabiting soil play an important role for vascular plants. Interaction between arbuscular mycorrhizal fungi, plants and soil microorganisms leads to many mutual advantages. However, the effectiveness of mycorrhizal fungi depends not only on biotic, but also abiotic factors such as physico-chemical properties of the soil, availability of water and biogenic elements, agricultural practices, and climatic conditions. First of all, it is important to adapt the arbuscular mycorrhizal fungi species to changing environmental conditions. The compactness of the soil and its structure have a huge impact on its biological activity. Soil pH reaction has a substantial impact on the mobility of ions in soil dilutions and their uptake by plants and soil microflora. Water excess can be a factor negatively affecting arbuscular mycorrhizal fungi because these microorganisms are sensitive to a lower availability of oxygen. Mechanical cultivation of the soil has a marginal impact on the arbuscular mycorrhizal fungi spores. However, soil translocation can cause changes to the population of the arbuscular mycorrhizal fungi abundance in the soil profile. The geographical location and topographic differentiation of cultivated soils, as well as the variability of climatic factors affect the population of the arbuscular mycorrhizal fungi in the soils and their symbiotic activity.

Ancestral state reconstruction infers phytopathogenic origins of sooty blotch and flyspeck fungi on apple.

PubMed

Ismail, Siti Izera; Batzer, Jean Carlson; Harrington, Thomas C; Crous, Pedro W; Lavrov, Dennis V; Li, Huanyu; Gleason, Mark L

2016-01-01

Members of the sooty blotch and flyspeck (SBFS) complex are epiphytic fungi in the Ascomycota that cause economically damaging blemishes of apples worldwide. SBFS fungi are polyphyletic, but approx. 96% of SBFS species are in the Capnodiales. Evolutionary origins of SBFS fungi remain unclear, so we attempted to infer their origins by means of ancestral state reconstruction on a phylogenetic tree built utilizing genes for the nuc 28S rDNA (approx. 830 bp from near the 59 end) and the second largest subunit of RNA polymerase II (RPB2). The analyzed taxa included the well-known genera of SBFS as well as non-SBFS fungi from seven families within the Capnodiales. The non-SBFS taxa were selected based on their distinct ecological niches, including plant-parasitic and saprophytic species. The phylogenetic analyses revealed that most SBFS species in the Capnodiales are closely related to plant-parasitic fungi. Ancestral state reconstruction provided strong evidence that plant-parasitic fungi were the ancestors of the major SBFS lineages. Knowledge gained from this study may help to better understand the ecology and evolution of epiphytic fungi. © 2016 by The Mycological Society of America.

Steroid toxicity and detoxification in ascomycetous fungi.

PubMed

Cvelbar, Damjana; Zist, Vanja; Kobal, Katja; Zigon, Dušan; Zakelj-Mavrič, Marija

2013-02-25

In the last couple of decades fungal infections have become a significant clinical problem. A major interest into fungal steroid action has been provoked since research has proven that steroid hormones are toxic to fungi and affect the host/fungus relationship. Steroid hormones were found to differ in their antifungal activity in ascomycetous fungi Hortaea werneckii, Saccharomyces cerevisiae and Aspergillus oryzae. Dehydroepiandrosterone was shown to be the strongest inhibitor of growth in all three varieties of fungi followed by androstenedione and testosterone. For their protection, fungi use several mechanisms to lower the toxic effects of steroids. The efficiency of biotransformation in detoxification depended on the microorganism and steroid substrate used. Biotransformation was a relatively slow process as it also depended on the growth phase of the fungus. In addition to biotransformation, steroid extrusion out of the cells contributed to the lowering of the active intracellular steroid concentration. Plasma membrane Pdr5 transporter was found to be the most effective, followed by Snq2 transporter and vacuolar transporters Ybt1 and Ycf1. Proteins Aus1 and Dan1 were not found to be involved in steroid import. The research of possible targets of steroid hormone action in fungi suggests that steroid hormones inhibit ergosterol biosynthesis in S. cerevisiae and H. werneckii. Results of this inhibition caused changes in the sterol content of the cellular membrane. The presence of steroid hormones most probably causes the degradation of the Tat2 permease and impairment of tryptophan import. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

[Biological treatments for contaminated soils: hydrocarbon contamination. Fungal applications in bioremediation treatment].

PubMed

Martín Moreno, Carmen; González Becerra, Aldo; Blanco Santos, María José

2004-09-01

Bioremediation is a spontaneous or controlled process in which biological, mainly microbiological, methods are used to degrade or transform contaminants to non or less toxic products, reducing the environmental pollution. The most important parameters to define a contaminated site are: biodegradability, contaminant distribution, lixiviation grade, chemical reactivity of the contaminants, soil type and properties, oxygen availability and occurrence of inhibitory substances. Biological treatments of organic contaminations are based on the degradative abilities of the microorganisms. Therefore the knowledge on the physiology and ecology of the biological species or consortia involved as well as the characteristics of the polluted sites are decisive factors to select an adequate biorremediation protocol. Basidiomycetes which cause white rot decay of wood are able to degrade lignin and a variety of environmentally persistent pollutants. Thus, white rot fungi and their enzymes are thought to be useful not only in some industrial process like biopulping and biobleaching but also in bioremediation. This paper provides a review of different aspects of bioremediation technologies and recent advances on ligninolytic metabolism research.

Molecular identification of Neofabraea species associated with bull's-eye rot on apple using rolling-circle amplification of partial EF-1α sequence.

PubMed

Lin, Huijiao; Jiang, Xiang; Yi, Jianping; Wang, Xinguo; Zuo, Ranling; Jiang, Zide; Wang, Weifang; Zhou, Erxun

2018-01-01

A rolling-circle amplification (RCA) method with padlock probes targeted on EF-1α regions was developed for rapid detection of apple bull's-eye rot pathogens, including Neofabraea malicorticis, N. perennans, N. kienholzii, and N. vagabunda (synonym: N. alba). Four padlock probes (PLP-Nm, PLP-Np, PLP-Nk, and PLP-Nv) were designed and tested against 28 samples, including 22 BER pathogen cultures, 4 closely related species, and 2 unrelated species that may cause serious apple decays. The assay successfully identified all the bull's-eye rot pathogenic fungi at the level of species, while no cross-reaction was observed in all target species and no false-positive reaction was observed with all strains used for reference. This study showed that the use of padlock probes and the combination of probe signal amplification by RCA provided an effective and sensitive method for the rapid identification of Neofabraea spp. The method could therefore be a useful tool for monitoring bull's-eye rot pathogens in port quarantine and orchard epidemiological studies.

Symmetries and solutions of the non-autonomous von Bertalanffy equation

NASA Astrophysics Data System (ADS)

Edwards, Maureen P.; Anderssen, Robert S.

2015-05-01

For growth in a closed environment, which is indicative of the situation in laboratory experiments, autonomous ODE models do not necessarily capture the dynamics under investigation. The importance and impact of a closed environment arise when the question under examination relates, for example, to the number of the surviving microbes, such as in a study of the spoilage and contamination of food, the gene silencing activity of fungi or the production of a chemical compound by bacteria or fungi. Autonomous ODE models are inappropriate as they assume that only the current size of the population controls the growth-decay dynamics. This is reflected in the fact that, asymptotically, their solutions can only grow or decay monotonically or asymptote. Non-autonomous ODE models are not so constrained. A natural strategy for the choice of non-autonomous ODEs is to take appropriate autonomous ones and change them to be non-autonomous through the introduction of relevant non-autonomous terms. This is the approach in this paper with the focus being the von Bertalanffy equation. Since this equation has independent importance in relation to practical applications in growth modelling, it is natural to explore the deeper relationships between the introduced non-autonomous terms through a symmetry analysis, which is the purpose and goal of the current paper. Infinitesimals are derived which allow particular forms of the non-autonomous von Bertalanffy equation to be transformed into autonomous forms for which some new analytic solutions have been found.

Susceptibilities of Candidatus Liberibacter asiaticus-infected and noninfected Diaphorina citri to entomopathogenic fungi and their detoxification enzyme activities under different temperatures.

PubMed

Hussain, Mubasher; Akutse, Komivi Senyo; Lin, Yongwen; Chen, Shiman; Huang, Wei; Zhang, Jinguan; Idrees, Atif; Qiu, Dongliang; Wang, Liande

2018-03-25

Some entomopathogenic fungi species, Isaria fumosorosea, and Hirsutella citriformis were found to be efficient against the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae). However, the susceptibility to these fungi increases when the psyllid infected with Candidatus Liberibacter asiaticus (Las), which is transmitted by D. citri and causes citrus greening disease. In this study, we examined the Las-infected and Las-uninfected D. citri susceptibility to entomopathogenic fungi at different temperature regimes (5-40°C). When D. citri adults exposed to cold temperature (5°C), they showed less susceptibility to entomopathogenic fungi as compared with control (27°C). Irrespective of infection with Las, a significantly positive correlation was observed between temperature and percentage mortality caused by different isolates of I. fumosorosea, 3A Ifr, 5F Ifr, PS Ifr, and H. citriformis isolates, HC3D and 2H. In contrast, a significantly negative correlation was found between temperature and percentage mortality for 3A Ifr for both Las-infected and Las-uninfected psyllids. Detoxification enzymes, Glutathione S-transferase levels in D. citri showed a negative correlation, whereas cytochrome P450 and general esterase levels were not correlated with changes in temperature. These findings revealed that detoxification enzymes and general esterase levels are not correlated with altered susceptibility to entomopathogenic fungi at the different temperature regimes. Conclusively, temperature fluctuations tested appear to be a significant factor impacting the management strategies of D. citri using entomopathogenic fungi. © 2018 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Isolation and characterization of mold fungi and insects infecting sawmill wood, and their inhibition by gamma radiation

NASA Astrophysics Data System (ADS)

Kalawate, Aparna; Mehetre, Sayaji

2015-12-01

This article describes the isolation, identification, and characterization of wood-rotting fungi and insects, and their inhibition was studied using gamma radiation. Products manufactured from plantation timber species are deteriorated by wood-rotting fungi such as Hypocrea lixii, Fusarium proliferatum, and Aspergillus flavus, and insects such as powderpost beetles. Proper preservation methods are necessary for ensuring a long service life of wood products. In this study, wood samples were treated with 2.5% copper ethanolamine boron (CEB) (10% w/v) and subsequently irradiated with gamma rays (10 kGy). It was observed that CEB-treated and gamma-irradiated samples controlled fungi and powderpost beetles significantly. As wood is a dead organic material, penetration of chemicals into it is very difficult. Gamma rays easily pass through wooden objects with hidden eggs and dormant spores of insects and fungi, respectively. Gamma irradiation was proved very effective in reducing damage caused by both fungi and insects.

Using hierarchical clustering of secreted protein families to classify and rank candidate effectors of rust fungi

USDA-ARS?s Scientific Manuscript database

Rust fungi are obligate biotrophic pathogens causing considerable damage on crop plants. P. graminis f. sp. tritici, the causal agent of wheat stem rust, and M. larici-populina, the poplar rust pathogen, have strong deleterious impact on wheat and poplar wood production, respectively. The recently r...

New insights into the obligate biotrophic lifestyle of rust fungi through comparative genomics

USDA-ARS?s Scientific Manuscript database

Wheat production continues to be plagued by rust pathogens and with the recent race shifts there is an increased concern regarding world food security. Three distinct rust fungi caused disease in wheat: Puccinia graminis f. sp. tritici (Pgt), stem rust or black stem rust; P. striiformis f. sp. triti...

Fungal prostatitis: an update.

PubMed

Mayayo, Emilio; Fernández-Silva, Fabiola

2014-06-01

Prostate pathology is a daily occurrence in urological and general medical consultations. Besides hyperplasia and neoplastic pathology, other processes, such as infectious ones, are also documented. Their etiology is diverse and varied. Within the infectious prostatic processes, fungi can also be a specific cause of prostatitis. Fungal prostatitis often appears in patients with impaired immunity and can also be rarely found in healthy patients. It can result from a disseminated infection, but it can also be localized. Fungal prostatitis is a nonspecific and harmless process. Diagnosis is commonly made by fine needle aspiration cytology or by biopsy. A number of fungi can be involved. Although there are not many reported cases, they are becoming more frequent, in particular in patients with some degree of immunodeficiency or those who live in areas where specific fungi are endemic or in visitors of those areas. We present a comprehensive review of the various forms of fungal prostatitis, and we describe the morphological characteristics of the fungi more frequently reported as causes of fungal prostatitis. We also report our own experience, aiming to alert physicians, urologists and pathologists of these particular infections.

Pneumonia (image)

MedlinePlus

Pneumonia is an inflammation of the lungs caused by an infection. Many different organisms can cause it, including bacteria, viruses, and fungi. Pneumonia is a common illness that affects millions of ...

Amplicon-Based Sequencing of Soil Fungi from Wood Preservative Test Sites

PubMed Central

Kirker, Grant T.; Bishell, Amy B.; Jusino, Michelle A.; Palmer, Jonathan M.; Hickey, William J.; Lindner, Daniel L.

2017-01-01

Soil samples were collected from field sites in two AWPA (American Wood Protection Association) wood decay hazard zones in North America. Two field plots at each site were exposed to differing preservative chemistries via in-ground installations of treated wood stakes for approximately 50 years. The purpose of this study is to characterize soil fungal species and to determine if long term exposure to various wood preservatives impacts soil fungal community composition. Soil fungal communities were compared using amplicon-based DNA sequencing of the internal transcribed spacer 1 (ITS1) region of the rDNA array. Data show that soil fungal community composition differs significantly between the two sites and that long-term exposure to different preservative chemistries is correlated with different species composition of soil fungi. However, chemical analyses using ICP-OES found levels of select residual preservative actives (copper, chromium and arsenic) to be similar to naturally occurring levels in unexposed areas. A list of indicator species was compiled for each treatment-site combination; functional guild analyses indicate that long-term exposure to wood preservatives may have both detrimental and stimulatory effects on soil fungal species composition. Fungi with demonstrated capacity to degrade industrial pollutants were found to be highly correlated with areas that experienced long-term exposure to preservative testing. PMID:29093702

Recent Developments in Using Advanced Sequencing Technologies for the Genomic Studies of Lignin and Cellulose Degrading Microorganisms

PubMed Central

Kameshwar, Ayyappa kumar Sista; Qin, Wensheng

2016-01-01

Lignin is a complex polyphenyl aromatic compound which exists in tight associations with cellulose and hemicellulose to form plant primary and secondary cell wall. Lignocellulose is an abundant renewable biomaterial present on the earth. It has gained much attention in the scientific community in recent years because of its potential applications in bio-based industries. Microbial degradation of lignocellulose polymers was well studied in wood decaying fungi. Based on the plant materials they degrade these fungi were classified as white rot, brown rot and soft rot. However, some groups of bacteria belonging to the actinomycetes, α-proteobacteria and β-proteobacteria were also found to be efficient in degrading lignocellulosic biomass but not well understood unlike the fungi. In this review we focus on recent advancements deployed for finding and understanding the lignocellulose degradation by microorganisms. Conventional molecular methods like sequencing 16s rRNA and Inter Transcribed Spacer (ITS) regions were used for identification and classification of microbes. Recent progression in genomics mainly next generation sequencing technologies made the whole genome sequencing of microbes possible in a great ease. The whole genome sequence studies reveals high quality information about genes and canonical pathways involved in the lignin and other cell wall components degradation. PMID:26884714

RNA extraction from decaying wood for (meta)transcriptomic analyses.

PubMed

Adamo, Martino; Voyron, Samuele; Girlanda, Mariangela; Marmeisse, Roland

2017-10-01

Wood decomposition is a key step of the terrestrial carbon cycle and is of economic importance. It is essentially a microbiological process performed by fungi and to an unknown extent by bacteria. To gain access to the genes expressed by the diverse microbial communities participating in wood decay, we developed an RNA extraction protocol from this recalcitrant material rich in polysaccharides and phenolic compounds. This protocol was implemented on 22 wood samples representing as many tree species from 11 plant families in the Angiosperms and Gymnosperms. RNA was successfully extracted from all samples and converted into cDNAs from which were amplified both fungal and bacterial protein coding genes, including genes encoding hydrolytic enzymes participating in lignocellulose hydrolysis. This protocol applicable to a wide range of decomposing wood types represents a first step towards a metatranscriptomic analysis of wood degradation under natural conditions.

A first insight on the biodegradation of limestone: the case of the World Heritage Convent of Christ

NASA Astrophysics Data System (ADS)

Rosado, Tânia; Silva, Mara; Galvão, Andreia; Mirão, José; Candeias, António; Caldeira, Ana Teresa

2016-12-01

The present study is a multidisciplinary approach applied to architectural stone materials of the Convent of Christ in Tomar (Portugal) in order to understand and mitigate the active decay processes. The structure and appearance of the stonework from the Convent of Christ are strongly affected by stains, biofilms and structural degradation. To investigate these phenomena, a multianalytical approach comprising X-ray microdiffraction, scanning electron microscopy, microRaman and microinfrared spectroscopy was applied to the examination of altered outdoor stone areas being detected calcium oxalates, carotenoids and microbial proliferation. The presence of these alteration products seems to be correlated with the microbial activity of bacteria, microalgae, cyanobacteria and filamentous fungi. This work showed that the application of complementary methodologies is an efficient strategy to characterise the stone decay, and constitute a starting point for successful conservation intervention plans that are urgent to ensure the preservation and safeguard of this emblematic monument.

Import risk analysis of fruit from Spain to Italy.

PubMed

Pani, G; Molinu, M G; Venditti, T; Dore, A; Ladu, G; D'Hallewin, G

2012-01-01

The International trade has to ensure food security and preserve both human health and the diffusion of animal and plant diseases among different countries. While organic horticultural production and trade are regulated by global guidelines, no specific restrictions relay to conventional commodities and almost free import-export occurs among UE countries. Consequently, the safety characteristics of imported fresh crops have become an important issue. On the basis of these considerations, the aim of the present study is to monitor the epiphytic microflora (particularly yeasts and fungi) carried by fresh fruit, imported from Spain to Italy. Particular attention was given to pathogenic microrganisms and to natural antagonists. In addition, the resistance to a few postharvest fungicides was determined for the isolated strains and compared to the local ones. Apples, Citrus fruits, stone fruits, and persimmon fruit were sampled at arrival of the container from Spain at the wholesale market in Sassari (Italy), this to prevent fruit contamination by local strains of microrganisms. The isolation was performed by rinsing and shaking (30 min at 100 rpm) the fruit in a beaker with 500 mL of sterile water. After concentration (7.5 mL), 100 microl of the rinse water was plated on potato dextrose agar (PDA). Isolation of pure colonies was performed by multiple streaking on plates, until unicellular cultures were obtained. Fifty three microrganisms, mainly fungi and yeasts, have been isolated and assayed in vitro and in vivo. Pathogenic behavior of isolated fungi was tested on fruits artificially wounded and only 7 strains out of 18 isolates caused decay. The resistance to different concentrations of imazalil (IMZ), tiabendazolo and azoxystrobin were tested in vitro for the pathogenic isolates. All isolates were completely inhibited with 1000 ppm IMZ evidencing that no resistant strains were present on the imported fruit. Since the baseline resistance, found for all isolates, was similar to the indigenous strains, we may conclude from this risk analysis that the import of the studied fruits produced in the 4 geographical areas of Spain does not increase the local baseline resistance.

Adaptive Immunity to Fungi

PubMed Central

Wüthrich, Marcel; Deepe, George S.; Klein, Bruce

2013-01-01

Only a handful of the more than 100,000 fungal species on our planet cause disease in humans, yet the number of life-threatening fungal infections in patients has recently skyrocketed as a result of advances in medical care that often suppress immunity intensely. This emerging crisis has created pressing needs to clarify immune defense mechanisms against fungi, with the ultimate goal of therapeutic applications. Herein, we describe recent insights in understanding the mammalian immune defenses deployed against pathogenic fungi. The review focuses on adaptive immune responses to the major medically important fungi and emphasizes how dendritic cells and subsets in various anatomic compartments respond to fungi, recognize their molecular patterns, and signal responses that nurture and shape the differentiation of T cell subsets and B cells. Also emphasized is how the latter deploy effector and regulatory mechanisms that eliminate these nasty invaders while also constraining collateral damage to vital tissue. PMID:22224780

A trait-based framework to understand life history of mycorrhizal fungi.

PubMed

Chagnon, Pierre-Luc; Bradley, Robert L; Maherali, Hafiz; Klironomos, John N

2013-09-01

Despite the growing appreciation for the functional diversity of arbuscular mycorrhizal (AM) fungi, our understanding of the causes and consequences of this diversity is still poor. In this opinion article, we review published data on AM fungal functional traits and attempt to identify major axes of life history variation. We propose that a life history classification system based on the grouping of functional traits, such as Grime's C-S-R (competitor, stress tolerator, ruderal) framework, can help to explain life history diversification in AM fungi, successional dynamics, and the spatial structure of AM fungal assemblages. Using a common life history classification framework for both plants and AM fungi could also help in predicting probable species associations in natural communities and increase our fundamental understanding of the interaction between land plants and AM fungi. Copyright © 2013 Elsevier Ltd. All rights reserved.

Adaptation to the Host Environment by Plant-Pathogenic Fungi.

PubMed

van der Does, H Charlotte; Rep, Martijn

2017-08-04

Many fungi can live both saprophytically and as endophyte or pathogen inside a living plant. In both environments, complex organic polymers are used as sources of nutrients. Propagation inside a living host also requires the ability to respond to immune responses of the host. We review current knowledge of how plant-pathogenic fungi do this. First, we look at how fungi change their global gene expression upon recognition of the host environment, leading to secretion of effectors, enzymes, and secondary metabolites; changes in metabolism; and defense against toxic compounds. Second, we look at what is known about the various cues that enable fungi to sense the presence of living plant cells. Finally, we review literature on transcription factors that participate in gene expression in planta or are suspected to be involved in that process because they are required for the ability to cause disease.

Detection of Fungi from an Indoor Environment using Loop-mediated Isothermal Amplification (LAMP) Method.

PubMed

Nakayama, Takako; Yamazaki, Takashi; Yo, Ayaka; Tone, Kazuya; Mahdi Alshahni, Mohamed; Fujisaki, Ryuichi; Makimura, Koichi

2017-01-01

　Loop-mediated isothermal amplification (LAMP) is a useful DNA detection method with high specificity and sensitivity. The LAMP reaction is carried out within a short time at a constant temperature without the need for thermal cycling. We developed a LAMP primer set for detecting a wide range of fungi by aligning the sequences of the large subunit ribosomal RNA gene of Candida albicans (Ascomycota), Cryptococcus neoformans (Basidiomycota), and Mucor racemosus (Mucorales). The threshold of C. albicans rDNA as template with our LAMP primer set was in the range of 10-100 copies per a reaction. In this study, we evaluated the correlation between colony forming units (CFU) and LAMP detection rate using the LAMP method for environmental fungi. The LAMP method should be a useful means of detecting fungi in indoor environments, disaster areas, or even in confined manned spacecraft to prevent allergies or infections caused by fungi.

Salinity induced effects on the growth rates and mycelia composition of basidiomycete and zygomycete fungi.

PubMed

Venâncio, C; Pereira, R; Freitas, A C; Rocha-Santos, T A P; da Costa, J P; Duarte, A C; Lopes, I

2017-12-01

Soil salinization, as the combination of primary and secondary events, can adversely affect organisms inhabiting this compartment. In the present study, the effects of increased salinity were assessed in four species of terrestrial fungi: Lentinus sajor caju, Phanerochaete chrysosporium, Rhizopus oryzae and Trametes versicolor. The mycelial growth and biochemical composition of the four fungi were determined under three exposure scenarios: 1) exposure to serial dilutions of natural seawater (SW), 2) exposure to serial concentrations of NaCl (potential surrogate of SW); and 3) exposure to serial concentrations of NaCl after a period of pre-exposure to low levels of NaCl. The toxicity of NaCl was slightly higher than that of SW, for all fungi species: the conductivities causing 50% of growth inhibition (EC 50 ) were within 14.9 and 22.0 mScm -1 for NaCl and within 20.2 and 34.1 mScm -1 for SW. Phanerochaete chrysosporium showed to be the less sensitive species, both for NaCl and SW. Exposure to NaCl caused changes in the biochemical composition of fungi, mainly increasing the production of polysaccharides. When fungi were exposed to SW this pattern of biochemical response was not observed. Fungi pre-exposed to low levels of salinity presented higher EC 50 than fungi non-pre-exposed, though 95% confidence limits overlapped, with the exception of P. chrysosporium. Pre-exposure to low levels of NaCl also induced changes in the biochemical composition of the mycelia of L. sajor caju and R. oryzae, relatively to the respective control. These results suggest that some terrestrial fungi may acquire an increased tolerance to NaCl after being pre-exposed to low levels of this salt, thus, suggesting their capacity to persist in environments that will undergo salinization. Furthermore, NaCl could be used as a protective surrogate of SW to derive safe salinity levels for soils, since it induced toxicity similar or higher than that of SW. Copyright © 2017 Elsevier Ltd. All rights reserved.

LC-MS/MS Tandem Mass Spectrometry for Analysis of Phenolic Compounds and Pentacyclic Triterpenes in Antifungal Extracts of Terminalia brownii (Fresen)

PubMed Central

Salih, Enass Y. A.; Fyhrquist, Pia; Abdalla, Ashraf M. A.; Abdelgadir, Abdelazim Y.; Kanninen, Markku; Sipi, Marketta; Luukkanen, Olavi; Fahmi, Mustafa K. M.; Elamin, Mai H.; Ali, Hiba A.

2017-01-01

Decoctions and macerations of the stem bark and wood of Terminalia brownii Fresen. are used in traditional medicine for fungal infections and as fungicides on field crops and in traditional granaries in Sudan. In addition, T. brownii water extracts are commonly used as sprays for protecting wooden houses and furniture. Therefore, using agar disc diffusion and macrodilution methods, eight extracts of various polarities from the stem wood and bark were screened for their growth-inhibitory effects against filamentous fungi commonly causing fruit, vegetable, grain and wood decay, as well as infections in the immunocompromised host. Ethyl acetate extracts of the stem wood and bark gave the best antifungal activities, with MIC values of 250 µg/mL against Nattrassia mangiferae and Fusarium verticillioides, and 500 µg/mL against Aspergillus niger and Aspergillus flavus. Aqueous extracts gave almost as potent effects as the ethyl acetate extracts against the Aspergillus and Fusarium strains, and were slightly more active than the ethyl acetate extracts against Nattrassia mangiferae. Thin layer chromatography, RP-HPLC-DAD and tandem mass spectrometry (LC-MS/MS), were employed to identify the chemical constituents in the ethyl acetate fractions of the stem bark and wood. The stem bark and wood were found to have a similar qualitative composition of polyphenols and triterpenoids, but differed quantitatively from each other. The stilbene derivatives, cis- (3) and trans- resveratrol-3-O-β-galloylglucoside (4), were identified for the first time in T. brownii. Moreover, methyl-(S)-flavogallonate (5), quercetin-7-β-O-di-glucoside (8), quercetin-7-O-galloyl-glucoside (10), naringenin-4′-methoxy-7-pyranoside (7), 5,6-dihydroxy-3′,4′,7-tri-methoxy flavone (12), gallagic acid dilactone (terminalin) (6), a corilagin derivative (9) and two oleanane type triterpenoids (1) and (2) were characterized. The flavonoids, a corilagin derivative and terminalin, have not been identified before in T. brownii. We reported earlier on the occurrence of methyl-S-flavogallonate and its isomer in the roots of T. brownii, but this is the first report on their occurrence in the stem wood as well. Our results justify the traditional uses of macerations and decoctions of T. brownii stem wood and bark for crop and wood protection and demonstrate that standardized extracts could have uses for the eco-friendly control of plant pathogenic fungi in African agroforestry systems. Likewise, our results justify the traditional uses of these preparations for the treatment of skin infections caused by filamentous fungi. PMID:29236070

Enrichment of arbuscular mycorrhizal fungi in a contaminated soil after rehabilitation.

PubMed

Lopes Leal, Patrícia; Varón-López, Maryeimy; Gonçalves de Oliveira Prado, Isabelle; Valentim Dos Santos, Jessé; Fonsêca Sousa Soares, Cláudio Roberto; Siqueira, José Oswaldo; de Souza Moreira, Fatima Maria

Spore counts, species composition and richness of arbuscular mycorrhizal fungi, and soil glomalin contents were evaluated in a soil contaminated with Zn, Cu, Cd and Pb after rehabilitation by partial replacement of the contaminated soil with non-contaminated soil, and by Eucalyptus camaldulensis planting with and without Brachiaria decumbens sowing. These rehabilitation procedures were compared with soils from contaminated non-rehabilitated area and non-contaminated adjacent soils. Arbuscular mycorrhizal fungi communities attributes were assessed by direct field sampling, trap culture technique, and by glomalin contents estimate. Arbuscular mycorrhizal fungi was markedly favored by rehabilitation, and a total of 15 arbuscular mycorrhizal fungi morphotypes were detected in the studied area. Species from the Glomus and Acaulospora genera were the most common mycorrhizal fungi. Number of spores was increased by as much as 300-fold, and species richness almost doubled in areas rehabilitated by planting Eucalyptus in rows and sowing B. decumbens in inter-rows. Contents of heavy metals in the soil were negatively correlated with both species richness and glomalin contents. Introduction of B. decumbens together with Eucalyptus causes enrichment of arbuscular mycorrhizal fungi species and a more balanced community of arbuscular mycorrhizal fungi spores in contaminated soil. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Emerging fungal infections among children: A review on its clinical manifestations, diagnosis, and prevention

PubMed Central

Jain, Akansha; Jain, Shubham; Rawat, Swati

2010-01-01

The incidence of fungal infections is increasing at an alarming rate, presenting an enormous challenge to healthcare professionals. This increase is directly related to the growing population of immunocompromised individuals especially children resulting from changes in medical practice such as the use of intensive chemotherapy and immunosuppressive drugs. Although healthy children have strong natural immunity against fungal infections, then also fungal infection among children are increasing very fast. Virtually not all fungi are pathogenic and their infection is opportunistic. Fungi can occur in the form of yeast, mould, and dimorph. In children fungi can cause superficial infection, i.e., on skin, nails, and hair like oral thrush, candida diaper rash, tinea infections, etc., are various types of superficial fungal infections, subcutaneous fungal infection in tissues under the skin and lastly it causes systemic infection in deeper tissues. Most superficial and subcutaneous fungal infections are easily diagnosed and readily amenable to treatment. Opportunistic fungal infections are those that cause diseases exclusively in immunocompromised individuals, e.g., aspergillosis, zygomycosis, etc. Systemic infections can be life-threatening and are associated with high morbidity and mortality. Because diagnosis is difficult and the causative agent is often confirmed only at autopsy, the exact incidence of systemic infections is difficult to determine. The most frequently encountered pathogens are Candida albicans and Aspergillus spp. But other fungi such as non-albicans Candida spp. are increasingly important. PMID:21180463

Tracking the emerging human pathogen Pseudallescheria boydii by using highly specific monoclonal antibodies.

PubMed

Thornton, Christopher R

2009-05-01

Pseudallescheria boydii has long been known to cause white grain mycetoma in immunocompetent humans, but it has recently emerged as an opportunistic pathogen of humans, causing potentially fatal invasive infections in immunocompromised individuals and evacuees of natural disasters, such as tsunamis and hurricanes. The diagnosis of P. boydii is problematic since it exhibits morphological characteristics similar to those of other hyaline fungi that cause infectious diseases, such as Aspergillus fumigatus and Scedosporium prolificans. This paper describes the development of immunoglobulin M (IgM) and IgG1 kappa-light chain monoclonal antibodies (MAbs) specific to P. boydii and certain closely related fungi. The MAbs bind to an immunodominant carbohydrate epitope on an extracellular 120-kDa antigen present in the spore and hyphal cell walls of P. boydii and Scedosporium apiospermum. The MAbs do not react with S. prolificans, Scedosporium dehoogii, or a large number of clinically relevant fungi, including A. fumigatus, Candida albicans, Cryptococcus neoformans, Fusarium solani, and Rhizopus oryzae. The MAbs were used in immunofluorescence and double-antibody sandwich enzyme-linked immunosorbent assays (DAS-ELISAs) to accurately differentiate P. boydii from other infectious fungi and to track the pathogen in environmental samples. Specificity of the DAS-ELISA was confirmed by sequencing of the internally transcribed spacer 1 (ITS1)-5.8S-ITS2 rRNA-encoding regions of environmental isolates.

Nitrogen isotope patterns in Alaskan black spruce reflect organic nitrogen sources and the activity of ectomycorrihizal fungi

Treesearch

Jordan R. Mayor; Edward A.G. Schuur; Michelle C. Mack; Teresa N. Hollingsworth; Erland Bääth

2012-01-01

Global patterns in soil, plant, and fungal stable isotopes of N (15N) show promise as integrated metrics of N cycling, particularly the activity of ectomycorrhizal (ECM) fungi. At small spatial scales, however, it remains difficult to differentiate the underlying causes of plant 15N variability and this limits the...

Draft genome sequences of Chrysoporthe austroafricana, Diplodia scrobiculata, Fusarium nygamai, Leptographium lundbergii, Limonomyces culmigenus, Stagonosporopsis tanaceti, and Thielaviopsis punctulata

USDA-ARS?s Scientific Manuscript database

Basidiomycete fungi in the genus Limonomyces are important pathogens of turfgrasses, causing pink patch and cream leaf blight diseases on numerous grass hosts worldwide. Much is unknown about the biology and taxonomy of these fungi, and molecular resources are extremely rare. Here, we report draft...

Gene discovery in EST sequences from the wheat leaf rust fungus puccinia triticina sexual spores, asexual spores and haustoria, compared to other rust and corn smut fungi

USDA-ARS?s Scientific Manuscript database

Background: Rust fungi are biotrophic basidiomycete plant pathogens that cause major diseases on plants and trees world-wide, affecting agriculture and forestry. Their biotrophic nature precludes many established molecular genetic manipulations and lines of research. The generation of genomic resour...

Simulated nitrogen deposition affects community structure of arbuscular mycorrhizal fungi in northern hardwood forests

Treesearch

Linda T.A. Van Diepen; Erik Lilleskov; Kurt S. Pregitzer

2011-01-01

Our previous investigation found elevated nitrogen deposition caused declines in abundance of arbuscular mycorrhizal fungi (AMF) associated with forest trees, but little is known about how nitrogen affects the AMF community composition and structure within forest ecosystems. We hypothesized that N deposition would lead to significant changes in the AMF community...

Signal amplification using colloidal gold in a biolayer interferometry-based immunosensor for the mycotoxin deoxynivalenol

USDA-ARS?s Scientific Manuscript database

Deoxynivalenol (DON) is a toxin produced by certain species of fungi that can infest wheat, barley, and corn. The fungi cause diseases in crops worldwide and some of the secondary metabolites, such as DON, can adversely affect animal health and food safety. To rapidly monitor DON in wheat a biosenso...

Are seed and cone pathogens causing significant losses in Pacific Northwest seed orchards?

Treesearch

E.E. Nelson; W.G. Thies; C.Y. Li

1986-01-01

Cones systematically collected in 1983 from eight Douglas-fir seed orchards in western Washington and Oregon yielded large numbers of common molds. Fungi isolated from apparently healthy, developing cones were similar to those from necrotic cones. Necrosis in cones aborted in early stages of development was apparently not associated with pathogenic fungi or bacteria....

DOE Office of Scientific and Technical Information (OSTI.GOV)

French, Jarrod B.; Ealick, Steven E.

Many plants, fungi, and bacteria catabolize allantoin as a mechanism for nitrogen assimilation. Recent reports have shown that in plants and some bacteria the product of hydrolysis of allantoin by allantoinase is the unstable intermediate ureidoglycine. While this molecule can spontaneously decay, genetic analysis of some bacterial genomes indicates that an aminotransferase may be present in the pathway. Here we present evidence that Klebsiella pneumoniae HpxJ is an aminotransferase that preferentially converts ureidoglycine and an {alpha}-keto acid into oxalurate and the corresponding amino acid. We determined the crystal structure of HpxJ, allowing us to present an explanation for substrate specificity.

Tackling emerging fungal threats to animal health, food security and ecosystem resilience.

PubMed

Fisher, Matthew C; Gow, Neil A R; Gurr, Sarah J

2016-12-05

Emerging infections caused by fungi have become a widely recognized global phenomenon. Their notoriety stems from their causing plagues and famines, driving species extinctions, and the difficulty in treating human mycoses alongside the increase of their resistance to antifungal drugs. This special issue comprises a collection of articles resulting from a Royal Society discussion meeting examining why pathogenic fungi are causing more disease now than they did in the past, and how we can tackle this rapidly emerging threat to the health of plants and animals worldwide.This article is part of the themed issue 'Tackling emerging fungal threats to animal health, food security and ecosystem resilience'. © 2016 The Author(s).

Functional compatibility in cucumber mycorrhizas in terms of plant growth performance and foliar nutrient composition.

PubMed

Ravnskov, S; Larsen, J

2016-09-01

Functional compatibility in cucumber mycorrhizas in terms of plant and fungal growth, and foliar nutrient composition from all possible combinations of six cucumber varieties and three species of arbuscular mycorrhizal (AM) fungi was evaluated. Measurements of foliar nutrient composition included N, P, K, Mg, Ca, Na, Fe, Zn, Mn and Cu. Growth of AM fungi was measured in terms of root colonisation, as examined with microscopy and the AM fungus biomarker fatty acid 16:1ω5 from both phospholipids and neutral lipids. Different responses of plant growth and foliar nutrient profiles were observed for the different AM symbioses examined. The AM fungus Claroideoglomus claroideum caused growth depression in association with four out of six cucumber varieties; Rhizophagus irregularis caused growth promotion in one of six cucumber varieties; whereas Funneliformis mosseae had no effect on the growth performance of any of the cucumber varieties examined. All three AM fungi markedly altered host plant shoot nutrient composition, with the strongest contrast observed between cucumber-R. irregularis symbioses and non-mycorrhizal cucumber plants, independent of cucumber variety. On the other hand, AM fungal growth in roots differed between the three AM fungi, but was unaffected by host genotype. Strong build-up of storage lipids was observed for R. irregularis, which was more moderate in the two other AM fungi. In conclusion, strong differential responses of cucumber varieties to inoculation with different AM fungi in terms of growth and shoot nutrient composition revealed high functional diversity in AM symbioses in cucumber plants. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

Comparative Genomic and Transcriptomic Analysis of Wangiella dermatitidis, A Major Cause of Phaeohyphomycosis and a Model Black Yeast Human Pathogen

PubMed Central

Chen, Zehua; Martinez, Diego A.; Gujja, Sharvari; Sykes, Sean M.; Zeng, Qiandong; Szaniszlo, Paul J.; Wang, Zheng; Cuomo, Christina A.

2014-01-01

Black or dark brown (phaeoid) fungi cause cutaneous, subcutaneous, and systemic infections in humans. Black fungi thrive in stressful conditions such as intense light, high radiation, and very low pH. Wangiella (Exophiala) dermatitidis is arguably the most studied phaeoid fungal pathogen of humans. Here, we report our comparative analysis of the genome of W. dermatitidis and the transcriptional response to low pH stress. This revealed that W. dermatitidis has lost the ability to synthesize alpha-glucan, a cell wall compound many pathogenic fungi use to evade the host immune system. In contrast, W. dermatitidis contains a similar profile of chitin synthase genes as related fungi and strongly induces genes involved in cell wall synthesis in response to pH stress. The large portfolio of transporters may provide W. dermatitidis with an enhanced ability to remove harmful products as well as to survive on diverse nutrient sources. The genome encodes three independent pathways for producing melanin, an ability linked to pathogenesis; these are active during pH stress, potentially to produce a barrier to accumulated oxidative damage that might occur under stress conditions. In addition, a full set of fungal light-sensing genes is present, including as part of a carotenoid biosynthesis gene cluster. Finally, we identify a two-gene cluster involved in nucleotide sugar metabolism conserved with a subset of fungi and characterize a horizontal transfer event of this cluster between fungi and algal viruses. This work reveals how W. dermatitidis has adapted to stress and survives in diverse environments, including during human infections. PMID:24496724

Dental Care in Pregnancy

MedlinePlus

... protective) coating on your teeth, which can cause tooth decay (cavities) or even tooth loss. Periodontal disease can ... prevent plaque buildup, which causes gum disease and tooth decay. Use a soft-bristled toothbrush because your gums ...

[Multicenter Prospective Observational Study of Fungal Keratitis--Identification and Susceptibility Test of Fungi].

PubMed

Sunada, Atsuko; Asari, Seishi; Inoue, Yoshitsugu; Ohashi, Yuichi; Suzuki, Takashi; Shimomura, Yoshikazu; Fukuda, Masahiko; Sotozono, Chie; Hatano, Hiroshi; Eguchi, Hiroshi; Araki-Sasaki, Kaoru; Hoshi, Saichi; Yaguchi, Takashi; Makimura, Koichi; Yokokura, Shunji; Mochizuki, Kiyofumi; Monden, Yu; Nejima, Ryohei

2016-01-01

To investigate the causative fungi of fungal keratitis in Japan and their drug susceptibility. Identification and antifungal susceptibility test for 8 drugs (micafungin, amphotericin B, flucytosine, fluconazole, itraconazole, voriconazole, miconazole and pimaricin) were performed using isolated fungi from patients with fungal keratitis treated at 27 facilities in Japan between November 1, 2011 and October 31, 2013. Fungal strains were detected in 72 (50.7%) out of 142 samples. The major isolates were Fusarium spp. (18), Candida parapsilosis (12), C. albicans (11) and Alternaria spp. (6), in all, fungi of 31 species were identified by gene analysis. In the yeast-like fungi, susceptibility rates were evident for more than 80% in voriconazole, pimaricin, flucytosine, micafungin, amphotericin B and fluconazole. In filamentous fungi, the susceptibility rate was less than 50% except for PMR (90%). Fusarium spp., which were susceptible to amphotericin B and pimaricin, showed lower susceptibility rates compared with other genera. Although various genera and species of fungi cause fungal keratitis, the obtained drug susceptibility data in this study demonstrates the different susceptibility patterns among the major isolates (Fusarium spp., C. parapsilosis, C. albicans and other groups). This is important evidence useful for fungal keratitis treatment.

Changing Epidemiology of Mucoralean Fungi: Chronic Cutaneous Infection Caused by Mucor irregularis.

PubMed

Chander, Jagdish; Kaur, Mandeep; Bhalla, Mala; Punia, Rajpal Singh; Singla, Nidhi; Bhola, Kalyani; Alastruey-Izquierdo, Ana; Stchigel, Alberto M; Guarro, Josep

2015-10-01

The fungi pertaining to order Mucorales usually cause an acute form of clinical disease called mucormycosis. A primary chronic presentation in an immunocompetent patient is a rare form of mucormycosis. Mucor irregularis is known for causing chronic cutaneous infections geographically confined to Asia, mainly in China. We describe a case of primary chronic cutaneous mucormycosis caused by M. irregularis from a new geographical niche in India, highlighting changing aspects of its epidemiology. The patient was a farmer with a history of skin lesions over the lower limb for the past 6 years. The biopsy taken from the lesions showed pauci-septate hyphae with right-angle branching on KOH wet mount as well as special fungal stains. On fungal culture, greyish-white cottony mycelial growth of Mucormycetes was obtained. The strain was finally identified as M. irregularis on macro- and microscopic features on 2 % MEA and DNA sequencing. The antifungal susceptibility was done using EUCAST broth microdilution method and was found to be susceptible to commonly used antifungal agents. The patient was started on oral itraconazole and saturated solution of potassium iodide (SSKI). While undergoing treatment for 2 months, he was lost to follow-up, however, after a year when he recently visited the hospital; the disease got completely healed with no new crops of skin lesions. Mucoralean fungi should also be suspected in cases with chronic presentation, in immunocompetent host, as there is emergence of such fungi in new endemic areas, particularly located in Asia. The role of other antifungal agents apart from amphotericin B for the treatment of chronic mucormycosis needs to be explored.

Conversion of cassava wastes for biofertilizer production using phosphate solubilizing fungi.

PubMed

Ogbo, Frank C

2010-06-01

Two fungi characterized as Aspergillus fumigatus and Aspergillus niger, isolated from decaying cassava peels were used to convert cassava wastes by the semi-solid fermentation technique to phosphate biofertilizer. The isolates solubilized Ca(3)(PO(4))(2), AlPO(4) and FePO(4) in liquid Pikovskaya medium, a process that was accompanied by acid production. Medium for the SSF fermentation was composed of 1% raw cassava starch and 3% poultry droppings as nutrients and 96% ground (0.5-1.5mm) dried cassava peels as carrier material. During the 14days fermentation, both test organisms increased in biomass in this medium as indicated by increases in phosphatase activity and drop in pH. Ground cassava peels satisfied many properties required of carrier material particularly in respect of the organisms under study. Biofertilizer produced using A. niger significantly (p<.05) improved the growth of pigeon pea [Cajanus cajan (L.) Millsp.] in pot experiments but product made with A. fumigatus did not. Copyright 2009 Elsevier Ltd. All rights reserved.

Two new hyaline-ascospored species of Trichoderma and their phylogenetic positions.

PubMed

Qin, W T; Zhuang, W Y

2016-01-01

Collections of hypocrealean fungi found on decaying wood in subtropical regions of China were examined. Two new species, Trichoderma confluens and T. hubeiense, were discovered and are described. Trichoderma confluens is characterized by its widely effuse to rarely pulvinate, yellow stromata with densely disposed yellowish brown ostioles, simple acremonium- to verticillium-like conidiophores, hyaline conidia and multiform chlamydospores. Trichoderma hubeiense has pulvinate, grayish yellow stromata with brownish ostioles, trichoderma- to verticillium-like conidiophores and hyaline conidia. The phylogenetic positions of the two fungi were investigated based on sequence analyses of RNA polymerase II subunit b and translation elongation factor 1-α genes. The results indicate that T. confluens belongs to the Hypocreanum clade and is associated with but clearly separated from T. applanatum and T. decipiens. Trichoderma hubeiense belongs to the Polysporum clade and related to T. bavaricum but obviously differs from other members of the clade in sequence data. Morphological distinctions between the new species and their close relatives are noted and discussed. © 2016 by The Mycological Society of America.

Pathogenicity, Ovicidal Action, and Median Lethal Concentrations (LC50) of Entomopathogenic Fungi against Exotic Spiralling Whitefly, Aleurodicus dispersus Russell

PubMed Central

Palaniappan, Karuppuchamy; Manickavasagam Pillai, Kalyanasundaram; Subbarayalu, Mohankumar; Madhaiyan, Ravi

2013-01-01

Biological control using entomopathogenic fungi could be a promising alternative to chemical control. Entomopathogenic fungi, Beauveria bassiana (Balsamo) Vuillemin, Metarhizium anisopliae (Metschnikoff) Sorokin, Lecanicillium lecanii (Zimmerm.) Zare and Gams, and Paecilomyces fumosoroseus (Wize) Brown and Smith, were tested for their pathogenicity, ovicidal effect, and median lethal concentrations (LC50) against exotic spiralling whitefly, Aleurodicus dispersus Russell. The applications were made at the rate of 2 × 109 conidia mL−1 for evaluating the pathogenicity and ovicidal effect of entomopathogenic fungi against A. dispersus. The results of pathogenicity test showed that P. fumosoroseus (P1 strain) was highly pathogenic to A. dispersus recording 100% mortality at 15 days after treatment (DAT). M. anisopliae (M2 strain) had more ovicidal effect causing 37.3% egg mortality at 8 DAT. However, L. lecanii (L1 strain) caused minimum egg hatchability (23.2%) at 10 DAT as compared to control (92.6%). The lowest LC50 produced by P. fumosoroseus (P1 strain) as 8.189 × 107 conidia mL−1 indicated higher virulence against A. dispersus. Hence, there is potential for use of entomopathogenic fungi in the field conditions as an alternate control method in combating the insect pests and other arthropod pests since they are considered natural mortality agents and are environmentally safe. PMID:24455279

Multiple genotypes within aecial clusters in Puccinia graminis and Puccinia coronata: improved understanding of the biology of cereal rust fungi.

PubMed

Berlin, Anna; Samils, Berit; Andersson, Björn

2017-01-01

Cereal rust fungi ( Puccinia spp.) are among the most economically important plant pathogens. These fungi have a complex life cycle, including five spore stages and two hosts. They infect one grass host on which they reproduce clonally and cause the cereal rust diseases, while the alternate host is required for sexual reproduction. Although previous studies clearly demonstrate the importance of the alternate host in creating genetic diversity in cereal rust fungi, little is known about the amount of novel genotypes created in each successful completion of a sexual reproduction event. In this study, single sequence repeat markers were used to study the genotypic diversity within aecial clusters by genotyping individual aecial cups. Two common cereal rusts, Puccinia graminis causing stem rust and Puccinia coronata the causal agent of crown rust were investigated. We showed that under natural conditions, a single aecial cluster usually include several genotypes, either because a single pycnial cluster is fertilized by several different pycniospores, or because aecia within the cluster are derived from more than one fertilized adjoining pycnial cluster, or a combination of both. Our results imply that although sexual events in cereal rust fungi in most regions of the world are relatively rare, the events that occur may still significantly contribute to the genetic variation within the pathogen populations.

Screening and identification of horticultural soil fungi for their evaluation against the plant parasitic nematode Nacobbus aberrans.

PubMed

Sosa, Ana L; Rosso, Laura C; Salusso, Fabricio A; Etcheverry, Miriam G; Passone, María A

2018-04-17

The plant-parasitic nematode Nacobbus aberrans is an endoparasite causing severe losses to a wide range of crops from North to South America. The use of native antagonistic fungi may be considered as a possible biological control alternative to reduce the damages caused by this species. Antagonistic effects of 66 potential nematophagous fungi against eggs (J1) and second-stage juveniles (J2) of N. aberrans, were evaluated in vitro on water agar. DGC test showed significant differences (p < 0.0001) in the efficacy of some fungal isolates tested, with parasitism levels for J1 and J2 of 0-95 and 1-78%, respectively. Five isolates of Purpureocillium lilacinum, Metarhizium robertsii and Plectosphaerella plurivora appeared as the most effective antagonists of N. aberrans, relying on hyphae and adhesive conidia in host infection processes.

Biological Ice Nuclei: They are Everywhere, What are Their Roles? (Invited)

NASA Astrophysics Data System (ADS)

Schnell, R. C.

2009-12-01

Biological ice nuclei active at temperatures warmer than -2C were first observed in the late 1960s associated with decaying grass and tree leaves; discovered more by accident than in a planned experiment. The active component of the decaying leaves was subsequently found to be produced by a few living bacteria, the two most ubiquitous being strains of P. syringae and E. herbicola. The active bacterial ice nuclei are easily deactivated by anaerobic, chemical and heat stresses. The same grass and tree leaves, when well decayed, generally contain less active ice nuclei (threshold temperatures of -5C to - 6C) in the 0.1 micron diameter range compared to the larger (1 micron) bacteria associated ice nuclei. The well decayed leaf litter ice nuclei are stable over a wide range of stresses and time; some samples of leaf derived nuclei stored at room temperature have exhibited the same ice nucleus concentration for over 30 years. Fungi also have active ice nuclei that are stable over many decades. Active ice nuclei are found in marine waters associated with plankton, and are produced by at least one marine dinoflagellate (Heterocapsa niei) that expresses ice nucleus activity almost as warm as terrestrial bacteria ice nuclei. Living ice nucleus bacteria have been found in marine fogs far at sea, in precipitation in Antarctica as well as over many continental areas, in air in the high Arctic, on vegetation around the world, on remote ice bound islands, and growing on and inside water storing vegetation on isolated tropical mountain peaks. But why? What is the evolutionary advantage for the ice nucleus gene to be expressed in such a wide range of environments, by greatly different species? There is an energy cost for bacteria and fungi to support the ice gene, so it probably is not a genetic anomaly. Possibly the ice nuclei play many roles? These could include damaging plants to acquire a food source, an aid in survival and dispersal in clouds, initiation of precipitation to help plant growth, initiating ice formation and subsequent scavenging of water vapor in cold climates (e.g. Arctic and high elevation lichen), living in symbiosis with high elevation vegetation that freezes nightly, and probably a range of others we have not observed or yet hypothesized. Bacterial ice nucleation is truly an intriguing and fantastic phenomenon for which we have just begun to understand.

Autumnal Biomass and Potential Productivity of Salt Marsh Fungi from 29° to 43° North Latitude along the United States Atlantic Coast†

PubMed Central

Newell, Steven Y.; Blum, Linda K.; Crawford, Richard E.; Dai, Ting; Dionne, Michele

2000-01-01

It has been established that substantial amounts of fungal mass accumulate in standing decaying smooth cordgrass (Spartina alterniflora) marshes in the southeastern United States (e.g., in standing decaying leaf blades with a total fungal organic mass that accounts for about 20% of the decay system organic mass), but it has been hypothesized that in marshes farther north this is not true. We obtained samples of autumnal standing decaying smooth cordgrass from sites in Florida to Maine over a 3-year period. The variation in latitude could not explain any of the variation in the living fungal standing crop (as determined by ergosterol content) or in the instantaneous rates of fungal growth (as determined by acetate incorporation into ergosterol at a standard temperature, 20°C), which led to the conclusion that the potential levels of fungal production per unit of naturally decaying grass are not different in northern and southern marshes. Twenty-one percent of the variation in the size of the living fungal standing crop could be explained by variation in the C/N ratio (the higher the C/N ratio the smaller the fungal crop), but the C/P ratio was not related to the size of the fungal crop. Instantaneous rates of fungal growth were negatively related to the size of the living fungal crop (r = −0.35), but these rates were not correlated with C/nutrient ratios. The same two predominant species of ascomycetes (one Phaeosphaeria species and one Mycosphaerella species) were found ejecting ascospores from standing decaying smooth cordgrass blades at all of the sites examined from Florida to Maine. PMID:10618221

Melanized Fungi in Human Disease

PubMed Central

Revankar, Sanjay G.; Sutton, Deanna A.

2010-01-01

Summary: Melanized or dematiaceous fungi are associated with a wide variety of infectious syndromes. Many are soil organisms and are generally distributed worldwide, though certain species appear to have restricted geographic ranges. Though they are uncommon causes of disease, melanized fungi have been increasingly recognized as important pathogens, with most reports occurring in the past 20 years. The spectrum of diseases with which they are associated has also broadened and includes allergic disease, superficial and deep local infections, pneumonia, brain abscess, and disseminated infection. For some infections in immunocompetent individuals, such as allergic fungal sinusitis and brain abscess, they are among the most common etiologic fungi. Melanin is a likely virulence factor for these fungi. Diagnosis relies on careful microscopic and pathological examination, as well as clinical assessment of the patient, as these fungi are often considered contaminants. Therapy varies depending upon the clinical syndrome. Local infection may be cured with excision alone, while systemic disease is often refractory to therapy. Triazoles such as voriconazole, posaconazole, and itraconazole have the most consistent in vitro activity. Further studies are needed to better understand the pathogenesis and optimal treatment of these uncommon infections. PMID:20930077

Anthropogenic N Deposition Slows Decay by Favoring Bacterial Metabolism: Insights from Metagenomic Analyses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Freedman, Zachary B.; Upchurch, Rima A.; Zak, Donald R.

Litter decomposition is an enzymatically-complex process that is mediated by a diverse assemblage of saprophytic microorganisms. It is a globally important biogeochemical process that can be suppressed by anthropogenic N deposition. In a northern hardwood forest ecosystem located in Michigan, USA, 20 years of experimentally increased atmospheric N deposition has reduced forest floor decay and increased soil C storage. Here, we paired extracellular enzyme assays with shotgun metagenomics to assess if anthropogenic N deposition has altered the functional potential of microbial communities inhabiting decaying forest floor. Experimental N deposition significantly reduced the activity of extracellular enzymes mediating plant cell wallmore » decay, which occurred concurrently with changes in the relative abundance of metagenomic functional gene pathways mediating the metabolism of carbohydrates, aromatic compounds, as well as microbial respiration. Moreover, experimental N deposition increased the relative abundance of 50 of the 60 gene pathways, the majority of which were associated with saprotrophic bacteria. Conversely, the relative abundance and composition of fungal genes mediating the metabolism of plant litter was not affected by experimental N deposition. Future rates of atmospheric N deposition have favored saprotrophic soil bacteria, whereas the metabolic potential of saprotrophic fungi appears resilient to this agent of environmental change. Results presented here provide evidence that changes in the functional capacity of saprotrophic soil microorganisms mediate how anthropogenic N deposition increases C storage in soil.« less

Anthropogenic N Deposition Slows Decay by Favoring Bacterial Metabolism: Insights from Metagenomic Analyses

DOE PAGES

Freedman, Zachary B.; Upchurch, Rima A.; Zak, Donald R.; ...

2016-03-02

Litter decomposition is an enzymatically-complex process that is mediated by a diverse assemblage of saprophytic microorganisms. It is a globally important biogeochemical process that can be suppressed by anthropogenic N deposition. In a northern hardwood forest ecosystem located in Michigan, USA, 20 years of experimentally increased atmospheric N deposition has reduced forest floor decay and increased soil C storage. Here, we paired extracellular enzyme assays with shotgun metagenomics to assess if anthropogenic N deposition has altered the functional potential of microbial communities inhabiting decaying forest floor. Experimental N deposition significantly reduced the activity of extracellular enzymes mediating plant cell wallmore » decay, which occurred concurrently with changes in the relative abundance of metagenomic functional gene pathways mediating the metabolism of carbohydrates, aromatic compounds, as well as microbial respiration. Moreover, experimental N deposition increased the relative abundance of 50 of the 60 gene pathways, the majority of which were associated with saprotrophic bacteria. Conversely, the relative abundance and composition of fungal genes mediating the metabolism of plant litter was not affected by experimental N deposition. Future rates of atmospheric N deposition have favored saprotrophic soil bacteria, whereas the metabolic potential of saprotrophic fungi appears resilient to this agent of environmental change. Results presented here provide evidence that changes in the functional capacity of saprotrophic soil microorganisms mediate how anthropogenic N deposition increases C storage in soil.« less

Strength loss in decayed wood

Treesearch

Rebecca E. Ibach; Patricia K. Lebow

2014-01-01

Wood is a durable engineering material when used in an appropriate manner, but it is susceptible to biological decay when a log, sawn product, or final product is not stored, handled, or designed properly. Even before the biological decay of wood becomes visually apparent, the decay can cause the wood to become structurally unsound. The progression of decay to that...

The Interaction of Human Pathogenic Fungi With C-Type Lectin Receptors.

PubMed

Goyal, Surabhi; Castrillón-Betancur, Juan Camilo; Klaile, Esther; Slevogt, Hortense

2018-01-01

Fungi, usually present as commensals, are a major cause of opportunistic infections in immunocompromised patients. Such infections, if not diagnosed or treated properly, can prove fatal. However, in most cases healthy individuals are able to avert the fungal attacks by mounting proper antifungal immune responses. Among the pattern recognition receptors (PRRs), C-type lectin receptors (CLRs) are the major players in antifungal immunity. CLRs can recognize carbohydrate ligands, such as β-glucans and mannans, which are mainly found on fungal cell surfaces. They induce proinflammatory immune reactions, including phagocytosis, oxidative burst, cytokine, and chemokine production from innate effector cells, as well as activation of adaptive immunity via Th17 responses. CLRs such as Dectin-1, Dectin-2, Mincle, mannose receptor (MR), and DC-SIGN can recognize many disease-causing fungi and also collaborate with each other as well as other PRRs in mounting a fungi-specific immune response. Mutations in these receptors affect the host response and have been linked to a higher risk in contracting fungal infections. This review focuses on how CLRs on various immune cells orchestrate the antifungal response and on the contribution of single nucleotide polymorphisms in these receptors toward the risk of developing such infections.

Capillary electrophoresis of conidia from cultivated microscopic filamentous fungi.

PubMed

Horká, Marie; Růzicka, Filip; Kubesová, Anna; Holá, Veronika; Slais, Karel

2009-05-15

In immunocompromised people fungal agents are able to cause serious infections with high mortality rate. An early diagnosis can increase the chances of survival of the affected patients. Simultaneously, the fungi produce toxins and they are frequent cause of allergy. Currently, various methods are used for detection and identification of these pathogens. They use microscopic examination and growth characteristic of the fungi. New methods are based on the analysis of structural elements of the target microorganisms such as proteins, polysaccharides, glycoproteins, nucleic acids, etc. for the construction of antibodies, probes, and primers for detection. The above-mentioned methods are time-consuming and elaborate. Here hydrophobic conidia from the cultures of different strains of the filamentous fungi were focused and separated by capillary zone electrophoresis and capillary isoelectric focusing. The detection was optimized by dynamic modifying of conidia by the nonionogenic tenside on the basis of pyrenebutanoate. Down to 10 labeled conidia of the fungal strains were fluorometrically detected, and isoelectric points of conidia were determined. The observed isoelectric points were compared with those obtained from the separation of the cultured clinical samples, and they were found to be not host-specific.

Parallels in amphibian and bat declines from pathogenic fungi.

PubMed

Eskew, Evan A; Todd, Brian D

2013-03-01

Pathogenic fungi have substantial effects on global biodiversity, and 2 emerging pathogenic species-the chytridiomycete Batrachochytrium dendrobatidis, which causes chytridiomycosis in amphibians, and the ascomycete Geomyces destructans, which causes white-nose syndrome in hibernating bats-are implicated in the widespread decline of their vertebrate hosts. We synthesized current knowledge for chytridiomycosis and white-nose syndrome regarding disease emergence, environmental reservoirs, life history characteristics of the host, and host-pathogen interactions. We found striking similarities between these aspects of chytridiomycosis and white-nose syndrome, and the research that we review and propose should help guide management of future emerging fungal diseases.

Early detection of fungi damage in citrus using NIR spectroscopy

NASA Astrophysics Data System (ADS)

Blasco, Jose; Ortiz, Coral; Sabater, Maria D.; Molto, Enrique

2000-12-01

Early detection of defects and diseases in fruit helps to correctly classify them and make more adequate decisions about the destination of the product: internal market, export or industry. An early fungi infection detection is especially important because a few infected fruits can disseminate the infection to a whole batch, causing great economic losses and affecting to further exports. Ensure products with excellent quality and absolute absence of fungi infections is particularly important in those batches for long conservation or to be exported. The main objective of this work is to detect the fungi infections before they can be visible. Near Infrared spectroscopy has been employed in this work, because it is a non-destructive technique and can be easily implemented on line due to the high speed and simplicity of the process.

Integrated economic and environmental analysis of agricultural straw reuse in edible fungi industry

PubMed Central

Lu, Wencong; Yu, Shuao; Huang, Hairong

2018-01-01

Background China currently faces severe environmental pollution caused by burning agricultural straw; thus, resource utilization of these straws has become an urgent policy and practical objective for the Chinese government. Methods This study develops a bio-economic model, namely, “straw resource utilization for fungi in China (SRUFIC),” on the basis of a field survey of an edible fungi plant in Zhejiang, China, to investigate an integrated economic and environmental performance of straw reuse in fungi production. Five scenarios, which cover changes in the production scale, wage level, and price fluctuations of the main product and inputs, are simulated. Results Results reveal that (1) the pilot plant potentially provides enhanced economic benefits and disposes added agricultural residues by adjusting its production strategy; (2) the economic performance is most sensitive to fungi price fluctuations, whereas the environmental performance is more sensitive to production scale and price of fungi than other factors; (3) expanding the production scale can be the most efficient means of improving the performance of a plant economically and environmentally. Discussion Overall, agricultural straw reuse in the edible fungi industry can not only reduce the environmental risk derived from burning abandoned straws but also introduce economic benefits. Thus, the straw reuse in the fungi industry should be practiced in China, and specific economic incentive policies, such as price support or subsidies, must be implemented to promote the utilization of agricultural straws in the fungi industry. PMID:29682417

Genome sequence of Penicillium solitum RS1, which causes postharvest apple decay

USDA-ARS?s Scientific Manuscript database

Penicillium species cause postharvest decay, commonly known as blue mold, in pome fruits such as apples and pears. Among the species that cause blue mold, P. expansum is the most virulent and prevalent, while P. solitum is signficantly less virulent. For devising novel strategies to prevent and to r...

Decomposition of New Woody Inputs as a Dry Tropical Forest Regenerates

NASA Astrophysics Data System (ADS)

Schilling, J. S.; Powers, J. S.; Ayres, A.; Kaffenberger, J. T.

2015-12-01

Modeling deadwood dynamics is limited by our empirical understanding of decomposition patterns and drivers. This gap is significant in dry tropical forests (and in the tropics, broadly) where forest regeneration is a management priority but where decision-making lacks resources. Our goal was to track decomposition and its biological drivers in tree boles added to the forest floor of a regenerating dry forest. We cut and then placed logs (~18 cm dia) of eight representative tree species in ground contact at two different sites (n=8, per site). We tracked density loss and element import/export in both sapwood and heartwood each 6 months over two years. We measured initial and final lignin, structural carbohydrates, nitrogen, and extractives. We also quantified insect gallery volumes, and used two residue 'signatures' to determine dominant fungal rot type: 1) dilute alkali solubility (DAS) and lignin:glucan loss. By year 2, mean density losses in sapwood were 11.6 - 44.4% among tree species, excluding one species that decomposed completely. The best predictor of density loss in sapwood was initial pH, but the correlation was negative rather than positive, as has been reported in temperate systems. Decay was consistently more advanced in sapwood than in heartwood, and although extractives were as high as 16.4% in heartwood, trait-density loss correlations were insignificant. Insects contributed little at this stage to density loss (<3%), and both lignin:glucan loss and DAS confirmed that white rot fungi dominated decomposition. Although element import dynamics broadly resembled those from temperate studies (e.g., Ca gain, P, K loss), there was high spatial variability. This perhaps related to zone line (spalting) complexity, suggesting intense competition among fungi colonizing small territories within the wood. Estimated CO2 fluxes from the test logs ranged from ~25 to 75% of the annual fluxes from litter fall at these sites. Collectively, these results implicate wood decomposition as an important component of dry forest carbon cycling. Emergent patterns from decomposers are also interesting in this case, where fungi assigned as a single functional group (white rot type) produced little variability in decay rates (Function 1) but high variability in element translocation (Function 2).

Occurrence of Root Rot and Vascular Wilt Diseases in Roselle (Hibiscus sabdariffa L.) in Upper Egypt.

PubMed

Hassan, Naglaa; Shimizu, Masafumi; Hyakumachi, Mitsuro

2014-03-01

Roselle (Hibiscus sabdariffa L.) family Malvaceae is an important crop used in food, cosmetics and pharmaceutics industries. Roselle is cultivated mainly in Upper Egypt (Qena and Aswan governorates) producing 94% of total production. Root rot disease of roselle is one of the most important diseases that attack both seedlings and adult plants causing serious losses in crop productivity and quality. The main objective of the present study is to identify and characterize pathogens associated with root rot and wilt symptoms of roselle in Qena, Upper Egypt and evaluate their pathogenicity under greenhouse and field condition. Fusarium oxysporum, Macrophomina phaseolina, Fusarium solani, Fusarium equiseti and Fusarium semitectum were isolated from the natural root rot diseases in roselle. All isolated fungi were morphologically characterized and varied in their pathogenic potentialities. They could attack roselle plants causing damping-off and root rot/wilt diseases in different pathogenicity tests. The highest pathogenicity was caused by F. oxysporum and M. phaseolina followed by F. solani. The least pathogenic fungi were F. equiseti followed by F. semitectum. It obviously noted that Baladi roselle cultivar was more susceptible to infection with all tested fungi than Sobhia 17 under greenhouse and field conditions. This is the first report of fungal pathogens causing root rot and vascular wilt in roselle in Upper Egypt.

Human Fungal Pathogens of Mucorales and Entomophthorales.

PubMed

Mendoza, Leonel; Vilela, Raquel; Voelz, Kerstin; Ibrahim, Ashraf S; Voigt, Kerstin; Lee, Soo Chan

2014-11-06

In recent years, we have seen an increase in the number of immunocompromised cohorts as a result of infections and/or medical conditions, which has resulted in an increased incidence of fungal infections. Although rare, the incidence of infections caused by fungi belonging to basal fungal lineages is also continuously increasing. Basal fungal lineages diverged at an early point during the evolution of the fungal lineage, in which, in a simplified four-phylum fungal kingdom, Zygomycota and Chytridiomycota belong to the basal fungi, distinguishing them from Ascomycota and Basidiomycota. Currently there are no known human infections caused by fungi in Chytridiomycota; only Zygomycotan fungi are known to infect humans. Hence, infections caused by zygomycetes have been called zygomycosis, and the term "zygomycosis" is often used as a synonym for "mucormycosis." In the four-phylum fungal kingdom system, Zygomycota is classified mainly based on morphology, including the ability to form coenocytic (aseptated) hyphae and zygospores (sexual spores). In the Zygomycota, there are 10 known orders, two of which, the Mucorales and Entomophthorales, contain species that can infect humans, and the infection has historically been known as zygomycosis. However, recent multilocus sequence typing analyses (the fungal tree of life [AFTOL] project) revealed that the Zygomycota forms not a monophyletic clade but instead a polyphyletic clade, whereas Ascomycota and Basidiomycota are monophyletic. Thus, the term "zygomycosis" needed to be further specified, resulting in the terms "mucormycosis" and "entomophthoramycosis." This review covers these two different types of fungal infections. Copyright © 2015 Cold Spring Harbor Laboratory Press; all rights reserved.

Human Fungal Pathogens of Mucorales and Entomophthorales

PubMed Central

Mendoza, Leonel; Vilela, Raquel; Voelz, Kerstin; Ibrahim, Ashraf S.; Voigt, Kerstin; Lee, Soo Chan

2015-01-01

In recent years, we have seen an increase in the number of immunocompromised cohorts as a result of infections and/or medical conditions, which has resulted in an increased incidence of fungal infections. Although rare, the incidence of infections caused by fungi belonging to basal fungal lineages is also continuously increasing. Basal fungal lineages diverged at an early point during the evolution of the fungal lineage, in which, in a simplified four-phylum fungal kingdom, Zygomycota and Chytridiomycota belong to the basal fungi, distinguishing them from Ascomycota and Basidiomycota. Currently there are no known human infections caused by fungi in Chytridiomycota; only Zygomycotan fungi are known to infect humans. Hence, infections caused by zygomycetes have been called zygomycosis, and the term “zygomycosis” is often used as a synonym for “mucormycosis.” In the four-phylum fungal kingdom system, Zygomycota is classified mainly based on morphology, including the ability to form coenocytic (aseptated) hyphae and zygospores (sexual spores). In the Zygomycota, there are 10 known orders, two of which, the Mucorales and Entomophthorales, contain species that can infect humans, and the infection has historically been known as zygomycosis. However, recent multilocus sequence typing analyses (the fungal tree of life [AFTOL] project) revealed that the Zygomycota forms not a monophyletic clade but instead a polyphyletic clade, whereas Ascomycota and Basidiomycota are monophyletic. Thus, the term “zygomycosis” needed to be further specified, resulting in the terms “mucormycosis” and “entomophthoramycosis.” This review covers these two different types of fungal infections. PMID:25377138

The toxicosis of Embellisia fungi from locoweed (Oxytropis lambertii) is similar to locoweed toxicosis in rats.

PubMed

McLain-Romero, J; Creamer, R; Zepeda, H; Strickland, J; Bell, G

2004-07-01

Locoweeds cause significant livestock poisoning and economic loss in the western United States. The toxicity of Embellisia sp. fungi isolated from locoweed was compared with locoweed toxicity using the rat as a model. Rats were fed diets containing locoweed, fungus and alfalfa, or alfalfa. Locoweed- and fungus-fed rats consumed swainsonine-containing food at approximately 1.3 mg x kg(-1) x d(-1), gained less weight (P = 0.001) and ate less than controls. Swainsonine is the principal agent responsible for inducing locoism in animals. The concentrations of alkaline phosphatase and aspartate aminotransferase enzymes were greater (P < 0.05) in serum of locoweed- and fungus-fed rats compared with control rats. Similar intracellular vacuolation was observed in renal, pancreatic, and hepatic tissues of rats that consumed either locoweed or fungus. Rats that ate locoweed or Embellisia fungi displayed indistinguishable toxicity symptoms. The Embellisia fungi from locoweed can induce toxicity without the plants. Locoism management strategies need to involve management of the Embellisia fungi.

Inhibition of HIV-1 Replication by Secondary Metabolites From Endophytic Fungi of Desert Plants

PubMed Central

Wellensiek, Brian P.; Ramakrishnan, Rajesh; Bashyal, Bharat P.; Eason, Yvette; Gunatilaka, A. A. Leslie; Ahmad, Nafees

2013-01-01

Most antiretroviral drugs currently in use to treat an HIV-1 infection are chemically synthesized and lead to the development of viral resistance, as well as cause severe toxicities. However, a largely unexplored source for HIV-1 drug discovery is endophytic fungi that live in a symbiotic relationship with plants. These fungi produce biologically active secondary metabolites, which are natural products that are beneficial to the host. We prepared several hundred extracts from endophytic fungi of desert plants and evaluated the inhibitory effects on HIV-1 replication of those extracts that showed less than 30% cytotoxicity in T-lymphocytes. Those extracts that inhibited viral replication were fractionated in order to isolate the compounds responsible for activity. Multiple rounds of fractionation and antiviral evaluation lead to the identification of four compounds, which almost completely impede HIV-1 replication. These studies demonstrate that metabolites from endophytic fungi of desert plants can serve as a viable source for identifying potent inhibitors of HIV-1 replication. PMID:23961302

Crossover fungal pathogens: the biology and pathogenesis of fungi capable of crossing kingdoms to infect plants and humans.

PubMed

Gauthier, Gregory M; Keller, Nancy P

2013-12-01

The outbreak of fungal meningitis associated with contaminated methylprednisolone acetate has thrust the importance of fungal infections into the public consciousness. The predominant pathogen isolated from clinical specimens, Exserohilum rostratum (teleomorph: Setosphaeria rostrata), is a dematiaceous fungus that infects grasses and rarely humans. This outbreak highlights the potential for fungal pathogens to infect both plants and humans. Most crossover or trans-kingdom pathogens are soil saprophytes and include fungi in Ascomycota and Mucormycotina phyla. To establish infection, crossover fungi must overcome disparate, host-specific barriers, including protective surfaces (e.g. cuticle, skin), elevated temperature, and immune defenses. This review illuminates the underlying mechanisms used by crossover fungi to cause infection in plants and mammals, and highlights critical events that lead to human infection by these pathogens. Several genes including veA, laeA, and hapX are important in regulating biological processes in fungi important for both invasive plant and animal infections. Copyright © 2013 Elsevier Inc. All rights reserved.

Associations of Conifer-Infesting Bark Beetles and Fungi in Fennoscandia

PubMed Central

Linnakoski, Riikka; de Beer, Z. Wilhelm; Niemelä, Pekka; Wingfield, Michael J.

2012-01-01

Bark beetles (Coleoptera, Scolytinae) have a widespread association with fungi, especially with ophiostomatoid fungi (Ascomycota) that cause blue staining of wood, and in some cases, serious tree diseases. In Fennoscandia, most studies of these fungi have focused on economically important bark beetle species and this is likely to have led to a biased view of the fungal biodiversity in the region. Recently, the associations between fungi and bark beetles in Fennoscandia have been shown to be more diverse than previously thought. Furthermore, they form complex and dynamic associations that are only now beginning to emerge. This review examines the current knowledge of the rather poorly known interactions between bark beetles, fungi and their conifer host trees in Fennoscandia. The diversity of ophiostomatoid species is discussed and the possible factors that influence the assemblages of fungal associates are considered for all species that are known to occur in the region. For many ophiostomatoid species found in Fennoscandia, little or nothing is known regarding their pathogenicity, particularly if they were to be transferred to new environments. We, therefore, draw attention to the possible threats of timber trade and climate change-induced invasions of new habitats by bark beetles and the fungi that can be moved along with them. PMID:26467956

Peptide-Like Nylon-3 Polymers with Activity against Phylogenetically Diverse, Intrinsically Drug-Resistant Pathogenic Fungi

PubMed Central

Rank, Leslie A.; Walsh, Naomi M.; Lim, Fang Yun

2018-01-01

ABSTRACT Understanding the dimensions of fungal diversity has major implications for the control of diseases in humans, plants, and animals and in the overall health of ecosystems on the planet. One ancient evolutionary strategy organisms use to manage interactions with microbes, including fungi, is to produce host defense peptides (HDPs). HDPs and their synthetic analogs have been subjects of interest as potential therapeutic agents. Due to increases in fungal disease worldwide, there is great interest in developing novel antifungal agents. Here we describe activity of polymeric HDP analogs against fungi from 18 pathogenic genera composed of 41 species and 72 isolates. The synthetic polymers are members of the nylon-3 family (poly-β-amino acid materials). Three different nylon-3 polymers show high efficacy against surprisingly diverse fungi. Across the phylogenetic spectrum (with the exception of Aspergillus species), yeasts, dermatophytes, dimorphic fungi, and molds were all sensitive to the effects of these polymers. Even fungi intrinsically resistant to current antifungal drugs, such as the causative agents of mucormycosis (Rhizopus spp.) and those with acquired resistance to azole drugs, showed nylon-3 polymer sensitivity. In addition, the emerging pathogens Pseudogymnoascus destructans (cause of white nose syndrome in bats) and Candida auris (cause of nosocomial infections of humans) were also sensitive. The three nylon-3 polymers exhibited relatively low toxicity toward mammalian cells. These findings raise the possibility that nylon-3 polymers could be useful against fungi for which there are only limited and/or no antifungal agents available at present. IMPORTANCE Fungi reside in all ecosystems on earth and impart both positive and negative effects on human, plant, and animal health. Fungal disease is on the rise worldwide, and there is a critical need for more effective and less toxic antifungal agents. Nylon-3 polymers are short, sequence random, poly-β-amino acid materials that can be designed to manifest antimicrobial properties. Here, we describe three nylon-3 polymers with potent activity against the most phylogenetically diverse set of fungi evaluated thus far in a single study. In contrast to traditional peptides, nylon-3 polymers are highly stable to proteolytic degradation and can be produced efficiently in large quantities at low cost. The ability to modify nylon-3 polymer composition easily creates an opportunity to tailor efficacy and toxicity, which makes these materials attractive as potential broad-spectrum antifungal therapeutics. PMID:29794056

Phomopsis seed decay of soybean

USDA-ARS?s Scientific Manuscript database

Soybean Phomopsis seed decay (PSD) causes poor seed quality and suppresses yield in most soybean-growing countries. The disease is caused primarily by the fungal pathogen Phomopsis longicolla along with other Phomopsis and Diaporthe spp. Infected seed range from symptomless to shriveled, elongated, ...

Duplications and losses in gene families of rust pathogens highlight putative effectors

Treesearch

Amanda L. Pendleton; Katherine E. Smith; Nicolas Feau; Francis M. Martin; Igor V. Grigoriev; Richard Hamelin; C.Dana Nelson; J.Gordon Burleigh; John M. Davis

2014-01-01

Rust fungi are a group of fungal pathogens that cause some of the world’s most destructive diseases of trees and crops . A shared characteristic among rust fungi is obligate biotrophy, the inability to complete a lifecycle without a host. This dependence on a host species likely affects patterns of gene expansion, contraction, and innovation within rust pathogen...

Quantifying sources of variation in the frequency of fungi associated with spruce beetles: implications for hypothesis testing and sampling methodology in bark beetle-symbiont relationships.

Treesearch

Brian H. Aukema; Richard A. Werner; Kirsten E. Haberkern; Barbara L. Illman; Murray K. Clayton; Kenneth F. Raffa

2005-01-01

The spruce beetle, Dendroctonus rufipennis (Kirby), causes landscape level mortality to mature spruce (Picea spp.) throughout western and northern North America. As with other bark beetles, this beetle is associated with a variety of fungi, whose ecological functions are largely unknown. It has been proposed that the relative...

EFFECTS OF SOME BIOINSECTICIDES AND ENTOMOPATHOGENIC FUNGI ON COLORADO POTATO BEETLE (LEPTINOTARSA DECEMLINEATA L.).

PubMed

Öztürk, H E; Güven, Ö; Karaca, I

2015-01-01

In this study, biological activity of entomopathogenic fungi (4 strains) isolated from the Colorado potato beetle and the commercial biopesticides containing entomopathogenic fungi; Priority® (Paecilomyces fumosoroseus), Nibortem® (Verticillium lecanii), Nostalgist® (Beauveria bassiana), Bio-Magic* (Metarhizium anisopliae), Bio-Nematon* (Paeciliomyces sp.) and plant extracts; Nimbedicine EC* (Azadiractin) were determined against Leptinotarsa decemlineata under laboratory conditions. An Imidacloprid active ingredient commercial insecticide was also used to compare the insecticidal activity and distilled water was used as control. The biological control agents were applied to 2nd-3rd larval instars, 4th larval instars and adults with spray and leaf dipping methods. Single concentration (10⁸ conidia/mL⁻¹) of entomopathogenic fungi and recommended dose of bioinsecticides were prepared for application. The number of dead insects were determined at 3, 5, and 7 days after applications. Experiments were conducted at 25 ±1° C and 60% ± 5 relative humidity with 16:8 h light: dark conditions. Entomopathogenic fungi and bioinsecticides were found to be more effective on larval stage than 4th larval instars and adults. In spray methods, Bio-Magic®, Nibortem®, and Nostalgist® caused 96.4%, 92.9% and 82.1% mortality on 2nd larval instars and 20%, 36.7% and 33.3% mortality on adults, respectively. All local fungal isolates (B. bassiana) applied on 2nd and 4th larval instars caused 100% mortality. Adults showed 58.6-86.2% mortality.

Synthesis of D-glucosamine quaternary ammonium derivatives and evaluation of their antifungal activity together with aminodeoxyglucose derivatives against two wood fungi Coriolus versicolor and Poria placenta: structure-activity relationships.

PubMed

Muhizi, Théoneste; Coma, Véronique; Grelier, Stéphane

2011-03-01

Structure-activity relationships are often reported in scientific studies. These may be employed in searching for new acceptable biocides to use against harmful microorganisms, because the biocides used hitherto encounter various problems, including lack of efficiency, high toxicity and persistence. Nowadays, scientists are trying to find new, environmentally acceptable biocides to replace these earlier biocides. Different compounds from renewable materials have been studied and have shown pronounced antifungal activity against wood fungi. These include aminopolysaccharide derivatives and different quaternary ammonium polymers. A biological study carried out with these products indicated a possible relationship between amino groups and differences in biological activity observed. In this study, an amino group was successively fixed to different carbon atoms of glucose, and glucosamine was also modified by both N-alkylation and quaternisation. The impact of the amino group position on antifungal activity against two wood decay fungi was investigated. The amino group at the anomeric position showed the highest antifungal activity against both Coriolus versicolor Quel. and Poria placenta (Fr.) Cooke. Furthermore, the positive impact of both N-alkylation and quaternisation on the growth of both strains was demonstrated. The anomeric position of the amino group and the N-alkylation and quaternisation of amino sugars considerably increase the antifungal activity of these compounds. Copyright © 2010 Society of Chemical Industry.

Effects of 2 fungicide formulations on microbial and macroinvertebrate leaf decomposition under laboratory conditions

USGS Publications Warehouse

Elskus, Adria; Smalling, Kelly L.; Hladik, Michelle; Kuivila, Kathryn

2016-01-01

Aquatic fungi contribute significantly to the decomposition of leaves in streams, a key ecosystem service. However, little is known about the effects of fungicides on aquatic fungi and macroinvertebrates involved with leaf decomposition. Red maple (Acer rubrum) leaves were conditioned in a stream to acquire microbes (bacteria and fungi), or leached in tap water (unconditioned) to simulate potential reduction of microbial biomass by fungicides. Conditioned leaves were exposed to fungicide formulations QUILT (azoxystrobin + propiconazole) or PRISTINE (boscalid + pyraclostrobin), in the presence and absence of the leaf shredder, Hyalella azteca (amphipods; 7-d old at start of exposures) for 14 d at 23 °C. QUILT formulation (~ 0.3 μg/L, 1.8 μg/L, 8 μg/L) tended to increase leaf decomposition by amphipods (not significant) without a concomitant increase in amphipod biomass, indicating potential increased consumption of leaves with reduced nutritional value. PRISTINE formulation (~ 33 μg/L) significantly reduced amphipod growth and biomass (p<0.05), effects similar to those observed with unconditioned controls. The significant suppressive effects of PRISTINE on amphipod growth, and the trend towards increased leaf decomposition with increasing QUILT concentration, indicate the potential for altered leaf decay in streams exposed to fungicides. Further work is needed to evaluate fungicide effects on leaf decomposition under conditions relevant to stream ecosystems, including temperature shifts and pulsed exposures to pesticide mixtures.

Draft genome sequence of Penicillium expansum (R19) that cause postharvest decay of apple fruit

USDA-ARS?s Scientific Manuscript database

Among the species that cause blue mold, isolates of P. expansum are the most prevalent and virulent species causing more than 50 percent of postharvest decay. We report the draft genome sequence of P. expansum (R19) in order to identify fungal virulence factors and to understand the mechanism of inf...

Screening soybean germplasm and commerical varieties for resistance to Phomopsis seed decay: results from 2012 trials

USDA-ARS?s Scientific Manuscript database

Soybean Phomopsis seed decay (PSD) causes poor seed quality and suppresses yield in most soybean production areas of the United States. In 2009, PSD caused a yield loss of over 12 million bushels in 16 southern states. The disease is primarily caused by Phomopsis longicolla along with other Phomopsi...

Reaction of maturity group IV soybean plant introductions to Phomopsis Seed Decay in Arkansas Mississippi and Missouri 2009

USDA-ARS?s Scientific Manuscript database

Soybean Phomopsis seed decay (PSD) causes poor seed quality and suppresses yield in most of soybean-growing states in United States. In 2009, PSD caused over 12 million bushel yield loss in 16 southern states. The disease is primarily caused by Phomopsis longicolla along with other Phomopsis and Dia...

Identification of soybean accessions with resistance to Phomopsis seed decay: joint effort from USDA and university scientists

USDA-ARS?s Scientific Manuscript database

Soybean Phomopsis seed decay (PSD) is primarily caused by Phomopsis longicolla along with other Phomopsis and Diaporthe spp. This disease causes poor seed quality and suppresses yield in most soybean-growing states in the United States. In 2009, PSD caused yield loss of over 12 million bushels in 16...

Where Have All These New Microbes Come From?

ERIC Educational Resources Information Center

Sobieski, Rodney J.

1984-01-01

Describes research activities and recent findings on disease-causing viruses, fungi, and bacteria. Includes a list of contemporary viruses and what they cause and lists of extra-classroom microbiology activities and student projects. (BC)

Conservation of Mannan Synthesis in Fungi of the Zygomycota and Ascomycota Reveals a Broad Diagnostic Target

PubMed Central

Hubbard, Breeana; Kvam, Alexander J.; Gates-Hollingsworth, Marcellene; Green, Heather R.; Soukup, Eric; Limper, Andrew H.; Kozel, Thomas R.

2018-01-01

ABSTRACT Ascomycetes and zygomycetes account for the majority of (i) fungi responsible for cutaneous, subcutaneous, and invasive human fungal infections, (ii) plant fungal pathogens, (iii) fungi that threaten global biodiversity, (iv) fungal agents of agricultural spoilage, and (v) fungi in water-damaged buildings. Rapid recognition of fungal infection (or contamination) enables early treatment (or remediation). A bioinformatics search found homologues of Saccharomyces cerevisiae Mnn9p present in members of the Zygomycota and Ascomycota phyla and absent in members of the Chytridiomycota and Basidiomycota. Mnn9p is a component of the yeast mannan polymerization complex and is necessary for α-1,6 mannan production. A monoclonal antibody (2DA6) was produced that was reactive with purified mannans of Mucor, Rhizopus, Aspergillus, Fusarium, and Candida species. Experimentation using a 2DA6 antigen capture enzyme-linked immunosorbent assay (ELISA) and extracts of fungi from the four phyla found agreement between the presence or absence of Mnn9p homologues and production or lack of production of mannan reactive with 2DA6. Studies of cell extracts from yeast mannan mutants identified α-1,6 mannan as the epitope recognized by 2DA6. To translate this finding into a point-of-use diagnostic, a 2DA6 lateral flow immunoassay was constructed that detected mannan in (i) extracts of dermatophytes and fungi that produce trauma-related infection and (ii) tissue from plants infected with Grosmannia clavigera or Sclerotium cepivorum. These studies (i) revealed that the conservation of α-1,6-linked mannan in fungi of the Zygomycota and Ascomycota can be exploited as a broad diagnostic target and (ii) have provided a means to detect that target in an immunoassay platform that is well suited for clinic or field use. IMPORTANCE A key question asked when faced with an infection, an infestation, or environmental damage is whether it is a fungus. Identification of fungi as the cause of the problem can lead to remediation or treatment. Zygomycetes and ascomycetes account for the vast majority of fungal causes of human, animal, and plant disease, large-scale biodiversity loss, agricultural spoilage, and contamination of water-damaged buildings. These studies revealed the conservation of a common cell wall structural component of zygomycetes and ascomycetes to be a diagnostic target applicable to multiple pathogenic fungi and have leveraged that insight for practical use. Monoclonal antibodies reactive with this pan-fungal structure were produced and used to construct immunoassays (including ELISA and lateral flow assay) for detection of a broad range of pathogenic fungi. PMID:29720523

Change in soil fungal community structure driven by a decline in ectomycorrhizal fungi following a mountain pine beetle (Dendroctonus ponderosae) outbreak.

PubMed

Pec, Gregory J; Karst, Justine; Taylor, D Lee; Cigan, Paul W; Erbilgin, Nadir; Cooke, Janice E K; Simard, Suzanne W; Cahill, James F

2017-01-01

Western North American landscapes are rapidly being transformed by forest die-off caused by mountain pine beetle (Dendroctonus ponderosae), with implications for plant and soil communities. The mechanisms that drive changes in soil community structure, particularly for the highly prevalent ectomycorrhizal fungi in pine forests, are complex and intertwined. Critical to enhancing understanding will be disentangling the relative importance of host tree mortality from changes in soil chemistry following tree death. Here, we used a recent bark beetle outbreak in lodgepole pine (Pinus contorta) forests of western Canada to test whether the effects of tree mortality altered the richness and composition of belowground fungal communities, including ectomycorrhizal and saprotrophic fungi. We also determined the effects of environmental factors (i.e. soil nutrients, moisture, and phenolics) and geographical distance, both of which can influence the richness and composition of soil fungi. The richness of both groups of soil fungi declined and the overall composition was altered by beetle-induced tree mortality. Soil nutrients, soil phenolics and geographical distance influenced the community structure of soil fungi; however, the relative importance of these factors differed between ectomycorrhizal and saprotrophic fungi. The independent effects of tree mortality, soil phenolics and geographical distance influenced the community composition of ectomycorrhizal fungi, while the community composition of saprotrophic fungi was weakly but significantly correlated with the geographical distance of plots. Taken together, our results indicate that both deterministic and stochastic processes structure soil fungal communities following landscape-scale insect outbreaks and reflect the independent roles tree mortality, soil chemistry and geographical distance play in regulating the community composition of soil fungi. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Trunk decays

Treesearch

Alex L. Shigo

1989-01-01

Trunk decays are major causes of low quality wood-wood with little or no economic value. As a forest practitioner you should be able to recognize trees at high risk for decay and remove them if timber production is your primary objective. Remember, however, that decayed trees often develop into den trees or nesting sites and provide essential habitat for wildlife....

Photodynamic inactivation of mold fungi spores by newly developed charged corroles.

PubMed

Preuß, Annegret; Saltsman, Irena; Mahammed, Atif; Pfitzner, Michael; Goldberg, Israel; Gross, Zeev; Röder, Beate

2014-04-05

The photodynamic effect, originally used in photodynamic therapy (PDT) for the treatment of different diseases, e.g. of cancer, has recently been introduced for the inactivation of bacteria. Mold fungi, which provoke health problems like allergies and diseases of the respiratory tract, are even more resistant and their biology is also very different. This study presents the development of four new photosensitizers, which, in combination with low doses of white light, inhibit the germination of mold fungi spores. Two of them even cause lethal damage to the conidia (spores) which are responsible for the spreading of mold fungi. The photoactivity of the newly synthesized corroles was obtained by their application on three different mold fungi: Aspergillus niger, Cladosporium cladosporoides, and Penicillium purpurgenum. To distinguish between inactivation of germination and permanent damage, the fungi were first incubated under illumination for examination of photosensitizer-induced growth inhibition and then left in darkness to test the survival of the conidia. None of the compounds displayed dark toxicity, but all of them attenuated or prevented germination when exposed to light, and the positively charged complexes induced a complete damage of the conidia. Copyright © 2014 Elsevier B.V. All rights reserved.

High diversity of airborne fungi in the hospital environment as revealed by meta-sequencing-based microbiome analysis

PubMed Central

Tong, Xunliang; Xu, Hongtao; Zou, Lihui; Cai, Meng; Xu, Xuefeng; Zhao, Zuotao; Xiao, Fei; Li, Yanming

2017-01-01

Invasive fungal infections acquired in the hospital have progressively emerged as an important cause of life-threatening infection. In particular, airborne fungi in hospitals are considered critical pathogens of hospital-associated infections. To identify the causative airborne microorganisms, high-volume air samplers were utilized for collection, and species identification was performed using a culture-based method and DNA sequencing analysis with the Illumina MiSeq and HiSeq 2000 sequencing systems. Few bacteria were grown after cultivation in blood agar. However, using microbiome sequencing, the relative abundance of fungi, Archaea species, bacteria and viruses was determined. The distribution characteristics of fungi were investigated using heat map analysis of four departments, including the Respiratory Intensive Care Unit, Intensive Care Unit, Emergency Room and Outpatient Department. The prevalence of Aspergillus among fungi was the highest at the species level, approximately 17% to 61%, and the prevalence of Aspergillus fumigatus among Aspergillus species was from 34% to 50% in the four departments. Draft genomes of microorganisms isolated from the hospital environment were obtained by sequence analysis, indicating that investigation into the diversity of airborne fungi may provide reliable results for hospital infection control and surveillance. PMID:28045065

Isolation of Cryptococcus neoformans and other opportunistic fungi from pigeon droppings.

PubMed

Soltani, Maryam; Bayat, Mansour; Hashemi, Seyed J; Zia, Mohammadali; Pestechian, Nader

2013-01-01

Invasive fungal infections cause considerable morbidity and mortality in immunocompromised hosts. Pigeon droppings could especially be a potential carrier in the spread of pathogenic yeasts and mold fungi into the environment. The objective of this study was to isolation of Cryptococcus neoformans and other opportunistic fungi from pigeon droppings. One hundred twenty samples of pigeon droppings were suspended 1:10 in saline solution and then cultured. Identification of C. neoformans was performed on bird seed agar, presence of a capsule on India ink preparation, urease production on urea agar medium and RapID yeast plus system. The identification of candida species was based on micro-morphological analysis on corn meal-Tween 80 agar, RapID yeast plus system and growth in CHROMagar candida. The identification of other fungi was based on macromorphologic, microscopic, biochemical and physiological characteristics. The highest frequency of yeasts and mold fungi were observed in Candida albicans 6.6% and Penicillium spp. 25%. The frequency rate of C. neoformans isolation was 2.5%. Several types of fungi are present in pigeon droppings that can spread in environment and transmit to children and elderly as well as immunocompromised patients who are at increased risk of contracting opportunistic diseases.

A rare disease mimics postoperative bile leakage: Invasive aspergillosis.

PubMed

Yazar, Fatih Mehmet; Urfalıoğlu, Aykut; Boran, Ömer Faruk; Sayar, Hamide; Kanat, Burhan Hakan; Emre, Arif; Cengiz, Emrah; Bülbüloğlu, Ertan

2016-09-01

Aspergillus fungi can cause serious infections, including intra-abdominal infection, particularly in patients with compromised immune system. Described in the present report is case of 46-year-old female patient who had undergone laparoscopic cholecystectomy (LC) at another healthcare facility. In early postoperative period, she had increasing complaints of swelling, nausea, and vomiting. On postoperative 19th day, she was referred to our clinic with diagnosis of acute abdomen. Surgery was performed with suspected possibility of bile leakage. However, pathological examination of soft, yellow-green mass found in subhepatic space determined it was fungus ball caused by fungi of the genus Aspergillus. Patient was diagnosed postoperative intra-abdominal aspergillosis (IAA).

The Indoor Fungus Cladosporium halotolerans Survives Humidity Dynamics Markedly Better than Aspergillus niger and Penicillium rubens despite Less Growth at Lowered Steady-State Water Activity.

PubMed

Segers, Frank J J; van Laarhoven, Karel A; Huinink, Hendrik P; Adan, Olaf C G; Wösten, Han A B; Dijksterhuis, Jan

2016-09-01

Indoor fungi cause damage in houses and are a potential threat to human health. Indoor fungal growth requires water, for which the terms water activity (aw) and relative humidity (RH) are used. The ability of the fungi Aspergillus niger, Cladosporium halotolerans, and Penicillium rubens at different developmental stages to survive changes in aw dynamics was studied. Fungi grown on media with high aw were transferred to a controlled environment with low RH and incubated for 1 week. Growth of all developmental stages was halted during incubation at RHs below 75%, while growth continued at 84% RH. Swollen conidia, germlings, and microcolonies of A. niger and P. rubens could not reinitiate growth when retransferred from an RH below 75% to a medium with high aw All developmental stages of C. halotolerans showed growth after retransfer from 75% RH. Dormant conidia survived retransfer to medium with high aw in all cases. In addition, retransfer from 84% RH to medium with high aw resulted in burst hyphal tips for Aspergillus and Penicillium Cell damage of hyphae of these fungi after incubation at 75% RH was already visible after 2 h, as observed by staining with the fluorescent dye TOTO-1. Thus, C. halotolerans is more resistant to aw dynamics than A. niger and P. rubens, despite its limited growth compared to that of these fungi at a lowered steady-state aw The survival strategy of this phylloplane fungus in response to the dynamics of aw is discussed in relation to its morphology as studied by cryo-scanning electron microscopy (cryo-SEM). Indoor fungi cause structural and cosmetic damage in houses and are a potential threat to human health. Growth depends on water, which is available only at certain periods of the day (e.g., during cooking or showering). Knowing why fungi can or cannot survive indoors is important for finding novel ways of prevention. Until now, the ability of fungi to grow on media with little available water at steady state (unchanging conditions) has been important for evaluating whether a fungus can grow indoors. In the present study, we found that the fungus Cladosporium halotolerans, a common indoor fungus, is more resistant to changes in available water than the fungi Aspergillus niger and Penicillium rubens, despite the fact that the latter fungi can grow on media with low water availability. We concluded that the ability of fungi to deal with changes in humidity is at least as important as the ability to grow on low-water media. Copyright © 2016 Segers et al.

Infections Caused by Fusarium Species in Pediatric Cancer Patients and Review of Published Literature.

PubMed

Arnoni, Mariana Volpe; Paula, Claudete Rodrigues; Auler, Marcos Ereno; Simões, Cirilo Cesar Naozuka; Nakano, Shirley; Szeszs, Maria Walderez; Melhem, Márcia de Souza Carvalho; Pereira, Virgínia Bodelão Richini; Garces, Hans Garcia; Bagagli, Eduardo; Silva, Eriques Gonçalves; de Macêdo, Melissa Ferreira; Ruiz, Luciana da Silva

2018-03-21

Fusarium species have emerged as responsible for a broad spectrum of infections, including superficial, locally invasive and disseminated ones, especially in the hospital environment. Since there are few reports of invasive and disseminated fusariosis in children, the aim of this study was to report four cases of nosocomial infection caused by this microorganism in children with cancer hospitalized in a public children's hospital located in Brazil. Two of these patients were female and two were male. All patients presented febrile neutropenia, while three patients had acute lymphocytic leukemia and one patient had Wilms' tumor as underlying disease. In two cases, fungi were isolated from blood and identified as Fusarium oxysporum species complex after phenotypic and genotypic studies, while in two other cases fungi were isolated from skin biopsies and identified as Fusarium solani species complex. One patient died 12 days after the onset of cutaneous lesions. All isolates, after susceptibility testing, presented high levels of minimum inhibitory concentration for itraconazole, voriconazole and amphotericin B. Considering the emergence of filamentous fungi as etiologic agents of nosocomial infections, health professionals should be aware of the problems these infections, especially fungal ones, may cause to debilitated patients.

A Drug-Sensitive Genetic Network Masks Fungi from the Immune System

PubMed Central

Wheeler, Robert T; Fink, Gerald R

2006-01-01

Fungal pathogens can be recognized by the immune system via their β-glucan, a potent proinflammatory molecule that is present at high levels but is predominantly buried beneath a mannoprotein coat and invisible to the host. To investigate the nature and significance of “masking” this molecule, we characterized the mechanism of masking and consequences of unmasking for immune recognition. We found that the underlying β-glucan in the cell wall of Candida albicans is unmasked by subinhibitory doses of the antifungal drug caspofungin, causing the exposed fungi to elicit a stronger immune response. Using a library of bakers' yeast (Saccharomyces cerevisiae) mutants, we uncovered a conserved genetic network that is required for concealing β-glucan from the immune system and limiting the host response. Perturbation of parts of this network in the pathogen C. albicans caused unmasking of its β-glucan, leading to increased β-glucan receptor-dependent elicitation of key proinflammatory cytokines from primary mouse macrophages. By creating an anti-inflammatory barrier to mask β-glucan, opportunistic fungi may promote commensal colonization and have an increased propensity for causing disease. Targeting the widely conserved gene network required for creating and maintaining this barrier may lead to novel broad-spectrum antimycotics. PMID:16652171

Shelf life extension of fresh fruit and vegetables by chitosan treatment.

PubMed

Romanazzi, Gianfranco; Feliziani, Erica; Baños, Silvia Bautista; Sivakumar, Dharini

2017-02-11

Among alternatives that are currently under investigation to replace the use of synthetic fungicides to control postharvest diseases in fresh produce and to extend their shelf life, chitosan application has shown promising disease control, at both preharvest and postharvest stages. Chitosan shows a dual mode of action, on the pathogen and on the plant, as it reduces the growth of decay-causing fungi and foodborne pathogens and induces resistance responses in the host tissues. Chitosan coating forms a semipermeable film on the surface of fruit and vegetables, thereby delaying the rate of respiration, decreasing weight loss, maintaining the overall quality, and prolonging the shelf life. Moreover, the coating can provide a substrate for incorporation of other functional food additives, such as minerals, vitamins, or other drugs or nutraceutical compounds that can be used to enhance the beneficial properties of fresh commodities, or in some cases the antimicrobial activity of chitosan. Chitosan coating has been approved as GRAS substance by USFDA, and its application is safe for the consumer and the environment. This review summarizes the most relevant and recent knowledge in the application of chitosan in postharvest disease control and maintenance of overall fruit and vegetable quality during postharvest storage.

Molecular mechanisms underlying the close association between soil Burkholderia and fungi.

PubMed

Stopnisek, Nejc; Zühlke, Daniela; Carlier, Aurélien; Barberán, Albert; Fierer, Noah; Becher, Dörte; Riedel, Katharina; Eberl, Leo; Weisskopf, Laure

2016-01-01

Bacterial species belonging to the genus Burkholderia have been repeatedly reported to be associated with fungi but the extent and specificity of these associations in soils remain undetermined. To assess whether associations between Burkholderia and fungi are widespread in soils, we performed a co-occurrence analysis in an intercontinental soil sample collection. This revealed that Burkholderia significantly co-occurred with a wide range of fungi. To analyse the molecular basis of the interaction, we selected two model fungi frequently co-occurring with Burkholderia, Alternaria alternata and Fusarium solani, and analysed the proteome changes caused by cultivation with either fungus in the widespread soil inhabitant B. glathei, whose genome we sequenced. Co-cultivation with both fungi led to very similar changes in the B. glathei proteome. Our results indicate that B. glathei significantly benefits from the interaction, which is exemplified by a lower abundance of several starvation factors that were highly expressed in pure culture. However, co-cultivation also gave rise to stress factors, as indicated by the increased expression of multidrug efflux pumps and proteins involved in oxidative stress response. Our data suggest that the ability of Burkholderia to establish a close association with fungi mainly lies in the capacities to utilize fungal-secreted metabolites and to overcome fungal defense mechanisms. This work indicates that beneficial interactions with fungi might contribute to the survival strategy of Burkholderia species in environments with sub-optimal conditions, including acidic soils.

Molecular mechanisms underlying the close association between soil Burkholderia and fungi

PubMed Central

Stopnisek, Nejc; Zühlke, Daniela; Carlier, Aurélien; Barberán, Albert; Fierer, Noah; Becher, Dörte; Riedel, Katharina; Eberl, Leo; Weisskopf, Laure

2016-01-01

Bacterial species belonging to the genus Burkholderia have been repeatedly reported to be associated with fungi but the extent and specificity of these associations in soils remain undetermined. To assess whether associations between Burkholderia and fungi are widespread in soils, we performed a co-occurrence analysis in an intercontinental soil sample collection. This revealed that Burkholderia significantly co-occurred with a wide range of fungi. To analyse the molecular basis of the interaction, we selected two model fungi frequently co-occurring with Burkholderia, Alternaria alternata and Fusarium solani, and analysed the proteome changes caused by cultivation with either fungus in the widespread soil inhabitant B. glathei, whose genome we sequenced. Co-cultivation with both fungi led to very similar changes in the B. glathei proteome. Our results indicate that B. glathei significantly benefits from the interaction, which is exemplified by a lower abundance of several starvation factors that were highly expressed in pure culture. However, co-cultivation also gave rise to stress factors, as indicated by the increased expression of multidrug efflux pumps and proteins involved in oxidative stress response. Our data suggest that the ability of Burkholderia to establish a close association with fungi mainly lies in the capacities to utilize fungal-secreted metabolites and to overcome fungal defense mechanisms. This work indicates that beneficial interactions with fungi might contribute to the survival strategy of Burkholderia species in environments with sub-optimal conditions, including acidic soils. PMID:25989372

Resistance to Phomopsis Seed Decay in soybean

USDA-ARS?s Scientific Manuscript database

Phomopsis seed decay (PSD) of soybean is caused primarily by the fungal pathogen, Phomopsis longicolla T.W. Hobbs along with other Phomopsis and Diaporthe spp. This disease causes poor seed quality and suppresses yield in most soybean-growing countries. Infected soybean seeds can be symptomless, but...

Effects of elevated tropospheric ozone and fluctuating moisture supply on loblolly pine seedlings inoculated with root infecting ophiostomatoid fungi

Treesearch

Jeff Chieppa; Lori Eckhardt; Art Chappelka

2016-01-01

Southern Pine Decline is a cause of premature mortality of Pinus species in the Southeastern United States. While the pathogenicity of ophiostomatoid fungi, associated with declining Pinus species, has been observed both in the laboratory and the field the driving mechanisms for success of fungal infection, as well as the bark-...

A super-infection in the cornea caused by Stemphylium, Acremonium, and α-Streptococcus.

PubMed

Hotta, Fumika; Eguchi, Hiroshi; Nishimura, Keiko; Kogiso, Masahiro; Ishimaru, Mayumi; Kusaka, Shunji; Shimomura, Yoshikazu; Yaguchi, Takashi

2017-03-09

Polymicrobial keratitis with fungus and bacteria can lead to blindness and is challenging to treat. Here, we introduce a case of fungal keratitis caused by two different strains in addition to definite bacterial super-infection caused by an α-Streptococcus sp., and describe the importance of microscopic examination. A 74-year-old woman, who had a past history of infection with leprosy, presented with conjunctival hyperaemia, pain, and corneal opacity in her right eye. Under the presumptive diagnosis of infectious keratitis, corneal scrapings were stained by various reagents and inoculated on several agar plates. Microscopic findings of the scrapings revealed fungi and a small number of Gram-positive cocci. Multiple anti-fungal therapies with levofloxacin ophthalmic solution were administered. Although empiric treatment was initially effective, keratitis recurred 10 days after its initiation. Repeated corneal scraping revealed an abundance of Gram-positive chain cocci and a small amount of fungi, resulting in the switching of an antibiotic medication from levofloxacin to moxifloxacin and cefmenoxime. Keratitis resolved gradually after the conversion. Stemphylium sp., Acremonium sp., and α-Streptococcus sp. were simultaneously isolated from the corneal scrapings. To the best of our knowledge, this is the first case of fungal keratitis caused by Stemphylium sp., and also the first case of super-infection in the cornea caused by two different fungi and one bacterium. Microscopic examination of the corneal scrapings was beneficial in rapid decision of changing to appropriate drug according to the dominancy of pathogenicity.

Microbial Mechanisms Mediating Increased Soil C Storage under Elevated Atmospheric N Deposition

PubMed Central

Freedman, Zachary; Zak, Donald R.; Xue, Kai; He, Zhili; Zhou, Jizhong

2013-01-01

Future rates of anthropogenic N deposition can slow the cycling and enhance the storage of C in forest ecosystems. In a northern hardwood forest ecosystem, experimental N deposition has decreased the extent of forest floor decay, leading to increased soil C storage. To better understand the microbial mechanisms mediating this response, we examined the functional genes derived from communities of actinobacteria and fungi present in the forest floor using GeoChip 4.0, a high-throughput functional-gene microarray. The compositions of functional genes derived from actinobacterial and fungal communities was significantly altered by experimental nitrogen deposition, with more heterogeneity detected in both groups. Experimental N deposition significantly decreased the richness and diversity of genes involved in the depolymerization of starch (∼12%), hemicellulose (∼16%), cellulose (∼16%), chitin (∼15%), and lignin (∼16%). The decrease in richness occurred across all taxonomic groupings detected by the microarray. The compositions of genes encoding oxidoreductases, which plausibly mediate lignin decay, were responsible for much of the observed dissimilarity between actinobacterial communities under ambient and experimental N deposition. This shift in composition and decrease in richness and diversity of genes encoding enzymes that mediate the decay process has occurred in parallel with a reduction in the extent of decay and accumulation of soil organic matter. Our observations indicate that compositional changes in actinobacterial and fungal communities elicited by experimental N deposition have functional implications for the cycling and storage of carbon in forest ecosystems. PMID:23220961

The role of chemical transport in the brown-rot decay resistance of modified wood

Treesearch

Samuel Zelinka; R. Ringman; A. Pilgard; E. E. Thybring; Joseph Jakes; K. Richter

2016-01-01

Chemical modification of wood increases decay resistance but the exact mechanisms remain poorly understood. Recently, Ringman and coauthors examined established theories addressing why modified wood has increased decay resistance and concluded that the most probable cause of inhibition and/or delay of initiation of brown-rot decay is lowering the equilibrium moisture...

Protecting log cabins from decay

Treesearch

R. M. Rowell; J. M. Black; L. R. Gjovik; W. C. Feist

1977-01-01

This report answers the questions most often asked of the Forest Service on the protection of log cabins from decay, and on practices for the exterior finishing and maintenance of existing cabins. Causes of stain and decay are discussed, as are some basic techniques for building a cabin that will minimize decay. Selection and handling of logs, their preservative...

Evaluation of commercial soybean cultivars for reaction to Phomopsis seed decay

USDA-ARS?s Scientific Manuscript database

Phomopsis seed decay (PSD), caused by Phomopsis longicolla (syn. Diaporthe longicolla), is an economically important soybean disease causing poor seed quality. Planting resistant cultivars is one of the most effective means to control PSD. In this study, 16 commercially available maturity groups IV ...

Development of the dichlorvos-ammonia (DV-AM) method for the visual detection of aflatoxigenic fungi.

PubMed

Yabe, Kimiko; Hatabayashi, Hidemi; Ikehata, Akifumi; Zheng, Yazhi; Kushiro, Masayo

2015-12-01

Aflatoxins (AFs) are carcinogenic and toxic secondary metabolites produced mainly by Aspergillus flavus and Aspergillus parasiticus. To monitor and regulate the AF contamination of crops, a sensitive and precise detection method for these toxigenic fungi in environments is necessary. We herein developed a novel visual detection method, the dichlorvos-ammonia (DV-AM) method, for identifying AF-producing fungi using DV and AM vapor on agar culture plates, in which DV inhibits the esterase in AF biosynthesis, causing the accumulation of anthraquinone precursors (versiconal hemiacetal acetate and versiconol acetate) of AFs in mycelia on the agar plate, followed by a change in the color of the colonies from light yellow to brilliant purple-red by the AM vapor treatment. We also investigated the appropriate culture conditions to increase the color intensity. It should be noted that other species producing the same precursors of AFs such as Aspergillus nidulans and Aspergillus versicolor could be discriminated from the Aspergillus section Flavi based on the differences of their phenotypes. The DV-AM method was also useful for the isolation of nonaflatoxigenic fungi showing no color change, for screening microorganisms that inhibit the AF production by fungi, and for the characterization of the fungi infecting corn kernels. Thus, the DV-AM method can provide a highly sensitive and visible indicator for the detection of aflatoxigenic fungi.

[Time course of microbial colonization of different voice prostheses].

PubMed

Schuldt, T; Dommerich, S; Pau, H-W; Kramp, B

2010-10-01

For the vocal rehabilitation of laryngectomized patients, voice prostheses are actually one of the best known methods. Caused by the surface colonisation with bacteria and fungi the life time of the prostheses is limited to 3-4 months. In a time period of 127 months we analysed the surface colonisation of 118 voice prostheses. The mean life time of the prostheses was 156 days. In reference to the prosthesis model we also recorded different times of usage (ESKA-Herrmann 141, Provox 2 184 and Provox 1 204 days (p>0.05)). In the microbiological examination the dominating bacteria were S. aureus, Klebsiella sp. and Proteus sp. It was possible to cultivate all these bacteria on every type of prosthesis used in the study. In addition C. albicans, C. glabrata, C. krusei and C. tropicalis were the main fungi on the silicone surface. Thereby a more frequent colonisation with C. krusei on ESKA-Herrmann prostheses was measured, caused by the bigger contact area with saliva on this model (p=0.034). Because of the similar position and way of function, all types of voice prostheses are colonized by almost the same species of bacteria and fungi. But in dependency of the type an affinity of individual species to special prostheses exist. The knowledge of these individual affinities is necessary for the further development of voice prostheses. Furthermore the diversity of bacteria and fungi species showed a level of saturation on the surface. This is caused by the limited space on the silicone prostheses. © Georg Thieme Verlag KG Stuttgart · New York.

Global Warming Will Bring New Fungal Diseases for Mammals

PubMed Central

Garcia-Solache, Monica A.; Casadevall, Arturo

2010-01-01

ABSTRACT Fungi are major pathogens of plants, other fungi, rotifers, insects, and amphibians, but relatively few cause disease in mammals. Fungi became important human pathogens only in the late 20th century, primarily in hosts with impaired immunity as a consequence of medical interventions or HIV infection. The relatively high resistance of mammals has been attributed to a combination of a complex immune system and endothermy. Mammals maintain high body temperatures relative to environmental temperatures, creating a thermally restrictive ambient for the majority of fungi. According to this view, protection given by endothermy requires a temperature gradient between those of mammals and the environment. We hypothesize that global warming will increase the prevalence of fungal diseases in mammals by two mechanisms: (i) increasing the geographic range of currently pathogenic species and (ii) selecting for adaptive thermotolerance for species with significant pathogenic potential but currently not pathogenic by virtue of being restricted by mammalian temperatures. PMID:20689745

Interdigital athlete's foot. The interaction of dermatophytes and resident bacteria.

PubMed

Leyden, J J; Kligman, A M

1978-10-01

Quantitative cultures in 140 cases of interdigital "athlete's foot" established the following clinical-microbiological correlations. In 39 cases of mild, scaling, relatively asymptomatic variety, fungi were recovered in 84% of cases. As the disease progressed to maceration, hyperkeratosis, and increased symptoms, recovery of fungi fell to 55% in moderately symptomatic and to 36% in severe cases. Symptomatic cases had increasing numbers of resident aerobic organisms, particularly large colony diphtheroids. Experimental manipulations of the interspace microflora in volunteers, monitored with quantitative cultures, demonstrated that symptomatic, macerated, hyperkeratotic process results from an overgrowth of resident organisms if the stratum corneum barrier is damaged by preexisting fungi, while overgrowth of the same organisms in normal, fungus-free interspaces does not produce lesions. These experiments support the conclusion that athlete's foot represents a continuum from a relatively asymptomatic, scaling eruption produced by fungi to a symptomatic, macerated, hyperkeratotic variety that is caused by an overgrowth of bacteria.

Chemical and biological approaches for mycotoxin control: a review.

PubMed

Edlayne, Gonçalez; Simone, Aquino; Felicio, Joana D

2009-06-01

Mycotoxins are metabolites and toxic substances produced by certain filamentous fungi that frequently contaminate food and agriculture commodities, which cause disease in animals or man. The toxigenic fungi belong to mainly three genera: Aspergillus, Penicillium and Fusarium. Examples of mycotoxins of greatest public health and agroeconomic significance include aflatoxins, ochratoxins, trichothecenes, zearalenone, fumonisins, patulin and ergot alkaloids. Commodities susceptible to direct contamination with mycotoxins include nuts, oilseeds and grains. Chemical and biological treatments have been attempted to minimize the risk of mycotoxins contamination or eliminate the fungi of food and feeds. One way to prevent or interfere with fungal growth and mycotoxin production is by use of synthetic or natural agents. Bacteria have been studied to control the mycotoxins production and fungal growth in food. Plant genotypes resistant to infection by toxigenic fungi have been also studied. This review will approach same patented methods applied to degrade, prevent and control of mycotoxins in food and feeds.

Ocular infections with dematiaceous fungi in two cats and a dog.

PubMed

Bernays, M E; Peiffer, R L

1998-08-15

Pigmented fungi were identified in ocular tissues from 2 cats and 1 dog. The first cat was euthanatized because of acute anterior uveitis that was unresponsive to treatment. On histologic examination, intraocular structures had been obliterated and replaced by a gray coagulum of inflammatory infiltrates and fungal elements. The second cat was treated for unilateral glaucoma that was unresponsive to treatment. A large retrobulbar mass, discovered and removed during an enucleation procedure, contained plant-origin foreign material. Keratitis, episcleritis, and orbital cellulitis with fungal elements were found on examination of the enucleated globe. The dog, examined because of a presumed corneal scratch of 2 weeks' duration that was unresponsive to treatment, had a corneal lesion subsequently removed by lamellar keratectomy that contained fungi on histologic examination. Infections caused by dematiaceous fungi are not common in domestic animals, and, to our knowledge, such infections in the eye have not been described.

Mechanisms Involved in Nematode Control by Endophytic Fungi.

PubMed

Schouten, Alexander

2016-08-04

Colonization of plants by particular endophytic fungi can provide plants with improved defenses toward nematodes. Evidently, such endophytes can be important in developing more sustainable agricultural practices. The mechanisms playing a role in this quantitative antagonism are poorly understood but most likely multifactorial. This knowledge gap obstructs the progress regarding the development of endophytes or endophyte-derived constituents into biocontrol agents. In part, this may be caused by the fact that endophytic fungi form a rather heterogeneous group. By combining the knowledge of the currently characterized antagonistic endophytic fungi and their effects on nematode behavior and biology with the knowledge of microbial competition and induced plant defenses, the various mechanisms by which this nematode antagonism operates or may operate are discussed. Now that new technologies are becoming available and more accessible, the currently unresolved mechanisms can be studied in greater detail than ever before.

Occurrence of Root Rot and Vascular Wilt Diseases in Roselle (Hibiscus sabdariffa L.) in Upper Egypt

PubMed Central

Hassan, Naglaa; Shimizu, Masafumi

2014-01-01

Roselle (Hibiscus sabdariffa L.) family Malvaceae is an important crop used in food, cosmetics and pharmaceutics industries. Roselle is cultivated mainly in Upper Egypt (Qena and Aswan governorates) producing 94% of total production. Root rot disease of roselle is one of the most important diseases that attack both seedlings and adult plants causing serious losses in crop productivity and quality. The main objective of the present study is to identify and characterize pathogens associated with root rot and wilt symptoms of roselle in Qena, Upper Egypt and evaluate their pathogenicity under greenhouse and field condition. Fusarium oxysporum, Macrophomina phaseolina, Fusarium solani, Fusarium equiseti and Fusarium semitectum were isolated from the natural root rot diseases in roselle. All isolated fungi were morphologically characterized and varied in their pathogenic potentialities. They could attack roselle plants causing damping-off and root rot/wilt diseases in different pathogenicity tests. The highest pathogenicity was caused by F. oxysporum and M. phaseolina followed by F. solani. The least pathogenic fungi were F. equiseti followed by F. semitectum. It obviously noted that Baladi roselle cultivar was more susceptible to infection with all tested fungi than Sobhia 17 under greenhouse and field conditions. This is the first report of fungal pathogens causing root rot and vascular wilt in roselle in Upper Egypt. PMID:24808737

Acidification of apple and orange hosts by Penicillium digitatum and Penicillium expansum.

PubMed

Vilanova, L; Viñas, I; Torres, R; Usall, J; Buron-Moles, G; Teixidó, N

2014-05-16

New information about virulence mechanisms of Penicillium digitatum and Penicillium expansum could be an important avenue to control fungal diseases. In this study, the ability of P. digitatum and P. expansum to enhance their virulence by locally modulating the pH of oranges and apples was evaluated. For each host, pH changes with a compatible pathogen and a non-host pathogen were recorded, and the levels of different organic acids were evaluated to establish possible relationships with host pH modifications. Moreover, fruits were harvested at three maturity stages to determine whether fruit maturity could affect the pathogens' virulence. The pH of oranges and apples decreased when the compatible pathogens (P. digitatum and P. expansum, respectively) decayed the fruit. The main organic acid detected in P. digitatum-decayed oranges was galacturonic acid produced as a consequence of host maceration in the rot development process. However, the obtained results showed that this acid was not responsible for the pH decrease in decayed orange tissue. The mixture of malic and citric acids could at least contribute to the acidification of P. digitatum-decayed oranges. The pH decrease in P. expansum decayed apples is related to the accumulation of gluconic and fumaric acids. The pH of oranges and apples was not affected when the non-host pathogen was not able to macerate the tissues. However, different organic acid contents were detected in comparison to healthy tissues. The main organic acids detected in P. expansum-oranges were oxalic and gluconic and in P. digitatum-apples were citric, gluconic and galacturonic. Further research is needed to identify the pathogenicity factors of both fungi because the contribution of organic acids has profound implications. Copyright © 2014 Elsevier B.V. All rights reserved.

[Dermatophytoses due to anthropophilic fungi in Cadiz, Spain, between 1997 and 2008].

PubMed

García-Martos, P; García-Agudo, L; Agudo-Pérez, E; Gil de Sola, F; Linares, M

2010-04-01

Cutaneous fungal infections are a major public health problem. The distribution of the dermatophytoses varies between countries and geographical areas. The aim of this study was to determine the incidence, epidemiology, etiology, and clinical course of the dermatophytoses caused by anthropophilic fungi in Cadiz, Spain, over the past 12 years. The study, conducted between 1997 and 2008, included 2,235 samples from lesions of the skin, hair, and nails of 2,220 patients with a clinical suspicion of mycosis. Samples were examined by microscopy using potassium hydroxide and were cultured on mycological media. The dermatophytes were identified by their macroscopic and microscopic characteristics. Cultures were positive in 283 cases (12.7%). Anthropophilic dermatophytes (53.3%) were more common than zoophilic (41.3%) and geophilic (5.3%) dermatophytes. Trichophyton rubrum (38.2%) was the predominant pathogen isolated, followed by Microsporum canis (22.3%) and Trichophyton mentagrophytes (15.5%). Five other species of anthropophilic fungi were identified: Trichophyton tonsurans (5.6%), Trichophyton violaceum (4.9%), Epidermophyton floccosum (2.8%), Trichophyton soudanense (1.0%), and Trichophyton schoenleinii (0.7%). Infections caused by the anthropophilic fungi included tinea unguium (29.1%), tinea corporis (25.8%), tinea pedis (19.2%), tinea cruris (11.9%), tinea capitis (5.3%), and tinea faciei (3.3%). The principal fungus responsible for dermatomycosis in Cadiz was T. rubrum, and its incidence has been rising since 2000. The prevalence of other anthropophilic fungi, such as T. tonsurans and T. violaceum, has increased, though this is not directly related to immigration. E. floccosum, T. soudanense, and T. schoenleinii are isolated occasionally.

Literature-Based Gene Curation and Proposed Genetic Nomenclature for Cryptococcus

PubMed Central

Inglis, Diane O.; Skrzypek, Marek S.; Liaw, Edward; Moktali, Venkatesh; Sherlock, Gavin

2014-01-01

Cryptococcus, a major cause of disseminated infections in immunocompromised patients, kills over 600,000 people per year worldwide. Genes involved in the virulence of the meningitis-causing fungus are being characterized at an increasing rate, and to date, at least 648 Cryptococcus gene names have been published. However, these data are scattered throughout the literature and are challenging to find. Furthermore, conflicts in locus identification exist, so that named genes have been subsequently published under new names or names associated with one locus have been used for another locus. To avoid these conflicts and to provide a central source of Cryptococcus gene information, we have collected all published Cryptococcus gene names from the scientific literature and associated them with standard Cryptococcus locus identifiers and have incorporated them into FungiDB (www.fungidb.org). FungiDB is a panfungal genome database that collects gene information and functional data and provides search tools for 61 species of fungi and oomycetes. We applied these published names to a manually curated ortholog set of all Cryptococcus species currently in FungiDB, including Cryptococcus neoformans var. neoformans strains JEC21 and B-3501A, C. neoformans var. grubii strain H99, and Cryptococcus gattii strains R265 and WM276, and have written brief descriptions of their functions. We also compiled a protocol for gene naming that summarizes guidelines proposed by members of the Cryptococcus research community. The centralization of genomic and literature-based information for Cryptococcus at FungiDB will help researchers communicate about genes of interest, such as those related to virulence, and will further facilitate research on the pathogen. PMID:24813190

Evaluation of diverse soybean germplasm for resistance to Phomopsis Seed Decay

USDA-ARS?s Scientific Manuscript database

Phomopsis seed decay (PSD) is a major cause of poor quality soybean seeds. The disease is caused primarily by the fungal pathogen, Phomopsis longicolla. To identify soybean lines with resistance to PSD, a total of 135 selected soybean germplasm accessions originally from 28 countries and in maturity...

Mechanisms of humic substances degradation by fungi

NASA Astrophysics Data System (ADS)

Chen, Y.; Hadar, Y.; Grinhut, T.

2012-04-01

Humic substances (HS) are formed by secondary synthesis reactions (humification) during the decay process and transformation of biomolecules originating from plants and other dead organisms. In nature, HS are extremely resistant to biological degradation. Thus, these substances are major components in the C cycle and in the biosphere and therefore, the understanding of the process leading to their formation and transformation and degradation is vital. Fungi active in the decomposition process of HS include mainly ascomycetes and basidiomycetes that are common in the upper layer of forest and grassland soils. Many basidiomycetes belong to the white-rot fungi (WRF) and litter-decomposing fungi (LDF). These fungi are considered to be the most efficient lignin degraders due to their nonspecific oxidizing enzymes: manganese peroxidase (MnP), lignin peroxidase (LiP) and laccase. Although bacteria dominate compost and participate in the turnover of HS, their ability to degrade stable macromolecules such as lignin and HS is limited. The overall objectives of this research were to corroborate biodegradation processes of HS by WRF. The specific objectives were: (i) To isolate, identify and characterize HS degrading WRF from biosolids (BS) compost; (ii) To study the biodegradation process of three types of HS, which differ in their structure, by WRF isolated from BS compost; and (iii) To investigate the mechanisms of HA degradation by WRF using two main approaches: (a) Study the physical and chemical analyses of the organic compounds obtained from direct fungal degradation of HA as well as elucidation of the relevant enzymatic reactions; and (b) Study the enzymatic and biochemical mechanisms involved during HA degradation. In order to study the capability of fungi to degrade HS, seventy fungal strains were isolated from biosolids (BS) compost. Two of the most active fungal species were identified based on rDNA sequences and designated Trametes sp. M23 and Phanerochaetesp., Y6. These strains were used throughout this study. This research shows that WRF are able to degrade different HA and under different culture conditions. We found that significant degradation occurred in high C/N media - conditions which are commonly present in the natural habitats of WRF. We suggest that in addition to lignin, these fungi play a crucial role during HS degradation in the environment. This work raises additional questions that are worth investigating in the future: what is the role of these fungi in dissolved organic matter degradation and its relationship to HA degradation? What is the detailed mechanism of iron reduction in Trametes sp. M23 as well as in other WRF? What is the exact involvement of hydroxyl radicals during degradation and what are the mechanisms of H2O2 production in Trametes sp. M23?

Enhanced resistance to Spodoptera litura in endophyte infected cauliflower plants.

PubMed

Thakur, Abhinay; Kaur, Sanehdeep; Kaur, Amarjeet; Singh, Varinder

2013-04-01

Endophytic fungi, which live within host plant tissues without causing any visible symptom of disease, are important mediators of plant-herbivore interactions. These endophytes enhance resistance of host plant against insect herbivores mainly by productions of various alkaloid based defensive compounds in the plant tissue or through alterations of plant nutritional quality. Two endophytic fungi, i.e., Nigrospora sp. and Cladosporium sp., were isolated from Tinospora cordifolia (Thunb.) Miers, a traditional indian medicinal plant. Cauliflower (Brassica oleracea L.) plants were inoculated with these two endophytic fungi. The effect of endophyte infected and uninfected cauliflower plants were measured on the survival and development of Spodoptera litura (Fab.), a polyphagous pest. Endophyte infected cauliflower plants showed resistance to S. litura in the form of significant increase in larval and pupal mortality in both the fungi. Inhibitory effects of endophytic fungi also were observed on adult emergence, longevity, reproductive potential, as well as hatchability of eggs. Thus, it is concluded that antibiosis to S. litura could be imparted by artificial inoculation of endophytes and this could be used to develop alternative ecologically safe control strategies.

Antagonism of rice phylloplane fungi against Cercospora oryzae

NASA Astrophysics Data System (ADS)

Mardani, A.; Hadiwiyono

2018-03-01

Narrow brown leaf spot (NBLS) caused by Cercospora oryzae Miyake is one of the important obstacle in rice cultivation that can decrease the productivity up to 40%. It has been known well that some phylloplane fungi are antagonistic to some leaf diseases. Phylloplane fungi of rice however haven’t been studied much and poorly understood as biological control agent of rice pathogen such C. oryzae. The research aimed to study the antagonism of some phylloplane fungi of rice against C. oryzae. At least 14 isolates of phylloplane fungi were collected which consisted of six pathogenic and eight nonpathogenic variants. All of nonpathogenic isolates were antagonistic against C. oryzae both in vitro and only one isolate could not inhibit the infection of the pathogen in vivo. Some isolates were identified as Aspergillus, Mucor, Penicillium, Fusarium, and Trichoderma. The isolate of Mucor and Fusarium could inhibit the highest growth of pathogen on potato dextrose medium that were at 36.0% and 35.5% respectively. Whereas on artificial inoculation on rice, some isolates such Penicillium and Fusarium could inhibit most effectively and were significantly different to Mencozeb application with dosage 5g L-1.

Antibacterial Activity Symbiotic Fungi of Marine Sponge Axinella sp., Aspergillus Sydowii on Four Growth Medium

NASA Astrophysics Data System (ADS)

Widyaningsih, S.; Trianto, A.; Radjasa, OK; Wittriansyah, K.

2018-02-01

Many infectious diseases caused by Escherichia coli and Staphylococcus aureus which turned into a resistant pathogen. A symbiotic fungi of marine sponge Axinella sp., Aspergillus sydowii from the waters of Riung, East Nusa Tenggara, Indonesia showed antibacterial activity, cultured on the four media, MEB (ST), Noni Juice Media (MG), avocado leaves media (AL), and Soursop leaves media (SR). The symbiotic fungi was cultured for 14 days on each media. The largest weight of symbiotic fungi biomass on ST media 138,95gr and at least 99,12gr of AL media. Purification of bioactive compound is carried out using separatory funnel, and column chromatography. The highest rendemen of extracts on SR media was 3,67%, while the lowest in ST media was 1,22%. The bioactive test used diffusion agar method. Fungi extracts from four mediums have bioactivity against, E. coli and S. aureus. The biggest inhibition zone obtained from the extract of MG KN-15-3-1-3, with inhibition zone 10.71mm and 10.98mm against E. coli and S. aureus.

In vivo interactions of entomopathogenic fungi, Beauveria spp. and Metarhizium anisopliae with selected opportunistic soil fungi of sugarcane ecosystem.

PubMed

Geetha, N; Preseetha, M; Hari, K; Santhalakshmi, G; Bai, K Subadra

2012-07-01

In the present study, the interactions of entomopathogenic fungi viz., Beauveria bassiana, Beauveria brongniartii and Metarhizium anisopliae among themselves and three other opportunistic soil fungi from the sugarcane ecosystem namely, Fusarium saachari, Aspergillus sp. and Penecillium sp. were assayed in vivo against Galleria mellonella larvae. The tested fungi were co-applied on IV instar G. mellonella @ 1 x 10(7) ml(-1), in combinations of two, at the interval of 24 hrs either preceding or succeeding each otherto assess their efficacy and sporulation rates. Results showed that often mortality rates did not correspond to the spore harvest of the mortality agent and presence of other fungus may be antagonistic. The efficacy of B. bassiana (90%) and B. brongniartii (100%) was not enhanced further but was negatively affected in most combinations with other fungi. In case of M. anisopliae compatibility was higher, resulting in higher mortality by application of B. bassiana before (100%) or after (83.3%) M. anisopliae than when it was applied alone (70%). During sporulation, B. bassiana faced the most intense competition from M. anisopliae (2.75 x 10(6) larva(-1)) and enhancement due to F sacchari irrespective of sequence of application. In case of B. brongniartii, sporulation was lowest in the combination of B. brongniartiipreceding M. anisopliae (1.83 x10(6) larva(-1)) and B. brongniartii succeeding B. bassiana (1.58 x 10(6) larva(-1)). Of all fungi tested, except F sacchari (65.33 x 10(6) larva(-1)) all the other species affected sporulation of M. ansiopliae with the least in treatment of B. bassiana application following M. anisopliae. Similar kind of interaction was observed during sporulation of soil fungi when combined with entomopathogenic fungi, though individually they could not cause mortality of larvae.

Culture and molecular identification of fungal contaminants in edible bird nests.

PubMed

Chen, Jennifer Xiao Jing; Wong, Shew Fung; Lim, Patricia Kim Chooi; Mak, Joon Wah

2015-01-01

Widespread food poisoning due to microbial contamination has been a major concern for the food industry, consumers and governing authorities. This study is designed to determine the levels of fungal contamination in edible bird nests (EBNs) using culture and molecular techniques. Raw EBNs were collected from five house farms, and commercial EBNs were purchased from five Chinese traditional medicine shops (companies A-E) in Peninsular Malaysia. The fungal contents in the raw and commercial EBNs, and boiled and unboiled EBNs were determined. Culturable fungi were isolated and identified. In this study, the use of these methods revealed that all EBNs had fungal colony-forming units (CFUs) that exceeded the limit set by Standards and Industrial Research Institute of Malaysia (SIRIM) for yeast and moulds in EBNs. There was a significant difference (p < 0.05) in the number of types of fungi isolated from raw and commercial EBNs, but no significant difference in the reduction of the number of types of fungi after boiling the EBNs (p > 0.05). The types of fungi isolated from the unboiled raw EBNs were mainly soil, plant and environmental fungi, while the types of fungi isolated from the boiled raw EBNs, unboiled and boiled commercial EBNs were mainly environmental fungi. Aspergillus sp., Candida sp., Cladosporium sp., Neurospora sp. and Penicillum sp. were the most common fungi isolated from the unboiled and boiled raw and commercial EBNs. Some of these fungi are mycotoxin producers and cause opportunistic infections in humans. Further studies to determine the mycotoxin levels and methods to prevent or remove these contaminations from EBNs for safe consumption are necessary. The establishment and implementation of stringent regulations for the standards of EBNs should be regularly updated and monitored to improve the quality of the EBNs and consumer safety.

Genome, transcriptome, and secretome analysis of wood decay fungus Postia placenta supports unique mechanisms of lignocellulose conversion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martinez, Diego; Challacombe, Jean; Morgenstern, Ingo

2009-02-04

Brown-rot fungi such as Postia placenta are common inhabitants of forest ecosystems and are also largely responsible for the destructive decay of wooden structures. Rapid depolymerization of cellulose is a distinguishing feature of brown-rot, but the biochemical mechanisms and underlying genetics are poorly understood. Systematic examination of the P. placenta genome, transcriptome, and secretome revealed unique extracellular enzyme systems, including an unusual repertoire of extracellular glycoside hydrolases. Genes encoding exocellobiohydrolases and cellulose-binding domains, typical of cellulolytic microbes, are absent in this efficient cellulose-degrading fungus. When P. placenta was grown in media containing cellulose as sole carbon source, transcripts corresponding tomore » many hemicellulases and to a single putative β-1-4 endoglucanase were expressed at high levels relative to glucose grown cultures. These transcript profiles were confirmed by direct identification of peptides by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Also upregulated under cellulolytic culture conditions were putative iron reductases, quinone reductase, and structurally divergent oxidases potentially involved in extracellular generation of Fe(II) and H2O2. These observations are consistent with a biodegradative role for Fenton chemistry in which Fe(II) and H2O2 react to form hydroxyl radicals, highly reactive oxidants capable of depolymerizing cellulose. The P. placenta genome resources provide unparalleled opportunities for investigating such unusual mechanisms of cellulose conversion. More broadly, the genome offers insight into the diversification of lignocellulose degrading mechanisms in fungi. In particular, comparisons between P. placenta and the closely related white-rot fungus, Phanerochaete chrysosporium support an evolutionary shift from white-rot to brown-rot during which efficient depolymerization of lignin was lost.« less

Genome, transcriptome, and secretome analysis of wood decay fungus postia placenta supports unique mechanisms of lignocellulose conversion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martinez, Diego; Challacombe, Jean F; Misra, Monica

2008-01-01

Brown-rot fungi such as Postia placenta are common inhabitants of forest ecosystems and are also largely responsible for the destructive decay of wooden structures. Rapid depolymerization of cellulose is a distinguishing feature of brown-rot, but the biochemical mechanisms and underlying genetics are poorly understood. Systematic examination of the P. placenta genome, transcriptome and secretome revealed unique extracellular enzyme systems, including an unusual repertoire of extracellular glycoside hydrolases. Genes encoding exocellobiohydrolases and cellulose-binding domains, typical of cellulolytic microbes, are absent in this efficient cellulose-degrading fungus. When P. placenta was grown in medium containing cellulose as sole carbon source, transcripts corresponding tomore » many hemicellulases and to a single putative {beta}-1-4 endoglucanase were expressed at high levels relative to glucose grown cultures. These transcript profiles were confirmed by direct identification of peptides by liquid chromatography-tandem mass spectrometry (LC{center_dot}MSIMS). Also upregulated during growth on cellulose medium were putative iron reductases, quinone reductase, and structurally divergent oxidases potentially involved in extracellular generation of Fe(II) and H202. These observations are consistent with a biodegradative role for Fenton chemistry in which Fe(II) and H202 react to form hydroxyl radicals, highly reactive oxidants capable of depolymerizing cellulose. The P. placenta genome resources provide unparalleled opportunities for investigating such unusual mechanisms of cellulose conversion. More broadly, the genome offers insight into the diversification of lignocellulose degrading mechanisms in fungi. Comparisons to the closely related white-rot fungus Phanerochaete chrysosporium support an evolutionary shift from white-rot to brown-rot during which the capacity for efficient depolymerization of lignin was lost.« less

Genome, transcriptome, and secretome analysis of wood decay fungus Postia placenta supports unique mechanisms of lignocellulose conversion

PubMed Central

Martinez, Diego; Challacombe, Jean; Morgenstern, Ingo; Hibbett, David; Schmoll, Monika; Kubicek, Christian P.; Ferreira, Patricia; Ruiz-Duenas, Francisco J.; Martinez, Angel T.; Kersten, Phil; Hammel, Kenneth E.; Vanden Wymelenberg, Amber; Gaskell, Jill; Lindquist, Erika; Sabat, Grzegorz; Splinter BonDurant, Sandra; Larrondo, Luis F.; Canessa, Paulo; Vicuna, Rafael; Yadav, Jagjit; Doddapaneni, Harshavardhan; Subramanian, Venkataramanan; Pisabarro, Antonio G.; Lavín, José L.; Oguiza, José A.; Master, Emma; Henrissat, Bernard; Coutinho, Pedro M.; Harris, Paul; Magnuson, Jon Karl; Baker, Scott E.; Bruno, Kenneth; Kenealy, William; Hoegger, Patrik J.; Kües, Ursula; Ramaiya, Preethi; Lucas, Susan; Salamov, Asaf; Shapiro, Harris; Tu, Hank; Chee, Christine L.; Misra, Monica; Xie, Gary; Teter, Sarah; Yaver, Debbie; James, Tim; Mokrejs, Martin; Pospisek, Martin; Grigoriev, Igor V.; Brettin, Thomas; Rokhsar, Dan; Berka, Randy; Cullen, Dan

2009-01-01

Brown-rot fungi such as Postia placenta are common inhabitants of forest ecosystems and are also largely responsible for the destructive decay of wooden structures. Rapid depolymerization of cellulose is a distinguishing feature of brown-rot, but the biochemical mechanisms and underlying genetics are poorly understood. Systematic examination of the P. placenta genome, transcriptome, and secretome revealed unique extracellular enzyme systems, including an unusual repertoire of extracellular glycoside hydrolases. Genes encoding exocellobiohydrolases and cellulose-binding domains, typical of cellulolytic microbes, are absent in this efficient cellulose-degrading fungus. When P. placenta was grown in medium containing cellulose as sole carbon source, transcripts corresponding to many hemicellulases and to a single putative β-1–4 endoglucanase were expressed at high levels relative to glucose-grown cultures. These transcript profiles were confirmed by direct identification of peptides by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Also up-regulated during growth on cellulose medium were putative iron reductases, quinone reductase, and structurally divergent oxidases potentially involved in extracellular generation of Fe(II) and H2O2. These observations are consistent with a biodegradative role for Fenton chemistry in which Fe(II) and H2O2 react to form hydroxyl radicals, highly reactive oxidants capable of depolymerizing cellulose. The P. placenta genome resources provide unparalleled opportunities for investigating such unusual mechanisms of cellulose conversion. More broadly, the genome offers insight into the diversification of lignocellulose degrading mechanisms in fungi. Comparisons with the closely related white-rot fungus Phanerochaete chrysosporium support an evolutionary shift from white-rot to brown-rot during which the capacity for efficient depolymerization of lignin was lost. PMID:19193860

Production of bioproducts by endophytic fungi: chemical ecology, biotechnological applications, bottlenecks, and solutions.

PubMed

Yan, Lu; Zhao, Haobin; Zhao, Xixi; Xu, Xiaoguang; Di, Yichao; Jiang, Chunmei; Shi, Junling; Shao, Dongyan; Huang, Qingsheng; Yang, Hui; Jin, Mingliang

2018-05-29

Endophytes are microorganisms that colonize the interior of host plants without causing apparent disease. They have been widely studied for their ability to modulate relationships between plants and biotic/abiotic stresses, often producing valuable secondary metabolites that can affect host physiology. Owing to the advantages of microbial fermentation over plant/cell cultivation and chemical synthesis, endophytic fungi have received significant attention as a mean for secondary metabolite production. This article summarizes currently reported results on plant-endophyte interaction hypotheses and highlights the biotechnological applications of endophytic fungi and their metabolites in agriculture, environment, biomedicine, energy, and biocatalysts. Current bottlenecks in industrial development and commercial applications as well as possible solutions are also discussed.

Freeze-fracture of infected plant leaves in ethanol for scanning electron microscopic study of fungal pathogens.

PubMed

Moore, Jayma A; Payne, Scott A

2012-01-01

Fungi often are found within plant tissues where they cannot be visualized with the scanning electron microscope (SEM). We present a simple way to reveal cell interiors while avoiding many common causes of artifact. Freeze-fracture of leaf tissue using liquid nitrogen during the 100% ethanol step of the dehydration process just before critical point drying is useful in exposing intracellular fungi to the SEM.

Mixed Fungal Lung Infection with Aspergillus Fumigatus and Candida Albicans in a Immunocomprimised Patient: Case Report

PubMed Central

Vipparti, Haritha

2014-01-01

The frequency of invasive, opportunistic mycoses has increased significantly over the past 2 decades. In the immune-compromised host, many fungi, including species of fungi typically considered non-pathogenic, have the potential to cause serious morbidity and mortality. Here we report a rare case of mixed fungal infection of the lung with Candida albicans and Aspergillus fumigatus in a patient on prolonged steroid therapy. PMID:24959447

Peptide-Like Nylon-3 Polymers with Activity against Phylogenetically Diverse, Intrinsically Drug-Resistant Pathogenic Fungi.

PubMed

Rank, Leslie A; Walsh, Naomi M; Lim, Fang Yun; Gellman, Samuel H; Keller, Nancy P; Hull, Christina M

2018-01-01

Understanding the dimensions of fungal diversity has major implications for the control of diseases in humans, plants, and animals and in the overall health of ecosystems on the planet. One ancient evolutionary strategy organisms use to manage interactions with microbes, including fungi, is to produce host defense peptides (HDPs). HDPs and their synthetic analogs have been subjects of interest as potential therapeutic agents. Due to increases in fungal disease worldwide, there is great interest in developing novel antifungal agents. Here we describe activity of polymeric HDP analogs against fungi from 18 pathogenic genera composed of 41 species and 72 isolates. The synthetic polymers are members of the nylon-3 family (poly-β-amino acid materials). Three different nylon-3 polymers show high efficacy against surprisingly diverse fungi. Across the phylogenetic spectrum (with the exception of Aspergillus species), yeasts, dermatophytes, dimorphic fungi, and molds were all sensitive to the effects of these polymers. Even fungi intrinsically resistant to current antifungal drugs, such as the causative agents of mucormycosis ( Rhizopus spp.) and those with acquired resistance to azole drugs, showed nylon-3 polymer sensitivity. In addition, the emerging pathogens Pseudogymnoascus destructans (cause of white nose syndrome in bats) and Candida auris (cause of nosocomial infections of humans) were also sensitive. The three nylon-3 polymers exhibited relatively low toxicity toward mammalian cells. These findings raise the possibility that nylon-3 polymers could be useful against fungi for which there are only limited and/or no antifungal agents available at present. IMPORTANCE Fungi reside in all ecosystems on earth and impart both positive and negative effects on human, plant, and animal health. Fungal disease is on the rise worldwide, and there is a critical need for more effective and less toxic antifungal agents. Nylon-3 polymers are short, sequence random, poly-β-amino acid materials that can be designed to manifest antimicrobial properties. Here, we describe three nylon-3 polymers with potent activity against the most phylogenetically diverse set of fungi evaluated thus far in a single study. In contrast to traditional peptides, nylon-3 polymers are highly stable to proteolytic degradation and can be produced efficiently in large quantities at low cost. The ability to modify nylon-3 polymer composition easily creates an opportunity to tailor efficacy and toxicity, which makes these materials attractive as potential broad-spectrum antifungal therapeutics. Copyright © 2018 Rank et al.

Ophiostomatoid fungi associated with invasive Tetropium spp. (Fabr.) (Coleoptera:Cerambycidae) in Atlantic Canada.

Treesearch

Karin Jacobs; Keith A. Seifert; Ken J. Harrison; Georgette Smith; Thomas Kirisits

2003-01-01

Species of the Ascomycete genus Ophiostoma are well-known for causing stain in living trees and lumber, as well as devastating pathogens, for example O. ulmi and O. novo-ulmi, the causes of Dutch elm disease.

Emerging fungal diseases: the importance of the host.

PubMed

Procop, Gary W; Roberts, Glenn D

2004-09-01

More yeasts and molds are now recognized to cause more human disease than ever before. This development is not due to a change in the virulence of these fungi, but rather to changes in the human host. These changes include immunosuppression secondary to the pandemic of HIV, the use of life-saving advances in chemotherapy and organ transplantation, and the use of corticosteroids and other immunosuppressive agents to treat a variety of diseases. Fungi that were once considered common saprophytes are now recognized as potential pathogens in these patients. This situation necessitates better communication than ever between the clinician, pathologist, and clinical mycologist to ensure the prompt and accurate determination of the cause of fungal diseases.

Mites and fungi in heavily infested stores in the Czech Republic.

PubMed

Hubert, J; Stejskal, V; Munzbergová, Z; Kubátová, A; Vánová, M; Zd'árková, E

2004-12-01

Toxigenic and allergen-producing fungi represent a serious hazard to human food and animal feed safety. Ninety-four fungal species were isolated from mite-infested samples of seeds taken from Czech seed stores. Fungi were isolated from the surface of four kinds of seeds (wheat, poppy, lettuce, and mustard) and from the gut and external surface of five species of mites (i.e., Acarus siro L., 1758, Caloglyphus rhizoglyphoides (Zachvatkin, 1973), Lepidoglyphus destructor (Schrank, 1781), Tyrophagus putrescentnae (Schrank, 1781) and Cheyletus malaccensis Oudemans 1903) separately. Multivariate analysis of fungi complex composition showed that the frequency of fungal was species significantly influenced by the kind of seed. Fungal frequencies differed between mites gut and exoskeleton surface and between the surfaces of mites and seeds. Three groups of fungal species were recognized: 1) mite surface-associated fungi: Penicillium brevicompactum, Alternaria alternata, and Aspergillus versicolor; 2) mite surface- and seed-associated fungi: Aspergillus niger, Penicillium crustosum, Penicillium aurantiogriseum, Penicillium chrysogenum, and Aspergillus flavus; and 3) seed-associated fungi: Cladosporium herbarum, Mucor dimorphosporus f. dimorphosporus, Botrytis cinerea, Penicillium griseofulvum, and Eurotium repens. Mite-carried species of microfungi are known to produce serious mycotoxins (e.g., aflatoxin B1, cyclopiazonic acid, sterigmatocystin, ochratoxin A, and nephrotoxic glycopeptides) as well as allergen producers (e.g., A. alternata and P. brevicompactum). Storage mites may play an important role in the spread of some medically hazardous micromycetes. In addition, these mite-fungi associations may heighten the risk of occurrence of mycotoxins in food and feed stuffs and cause mixed contamination by fungal and mite allergens.

Conservation of Mannan Synthesis in Fungi of the Zygomycota and Ascomycota Reveals a Broad Diagnostic Target.

PubMed

Burnham-Marusich, Amanda R; Hubbard, Breeana; Kvam, Alexander J; Gates-Hollingsworth, Marcellene; Green, Heather R; Soukup, Eric; Limper, Andrew H; Kozel, Thomas R

2018-01-01

Ascomycetes and zygomycetes account for the majority of (i) fungi responsible for cutaneous, subcutaneous, and invasive human fungal infections, (ii) plant fungal pathogens, (iii) fungi that threaten global biodiversity, (iv) fungal agents of agricultural spoilage, and (v) fungi in water-damaged buildings. Rapid recognition of fungal infection (or contamination) enables early treatment (or remediation). A bioinformatics search found homologues of Saccharomyces cerevisiae Mnn9p present in members of the Zygomycota and Ascomycota phyla and absent in members of the Chytridiomycota and Basidiomycota. Mnn9p is a component of the yeast mannan polymerization complex and is necessary for α-1,6 mannan production. A monoclonal antibody (2DA6) was produced that was reactive with purified mannans of Mucor , Rhizopus , Aspergillus , Fusarium , and Candida species. Experimentation using a 2DA6 antigen capture enzyme-linked immunosorbent assay (ELISA) and extracts of fungi from the four phyla found agreement between the presence or absence of Mnn9p homologues and production or lack of production of mannan reactive with 2DA6. Studies of cell extracts from yeast mannan mutants identified α-1,6 mannan as the epitope recognized by 2DA6. To translate this finding into a point-of-use diagnostic, a 2DA6 lateral flow immunoassay was constructed that detected mannan in (i) extracts of dermatophytes and fungi that produce trauma-related infection and (ii) tissue from plants infected with Grosmannia clavigera or Sclerotium cepivorum These studies (i) revealed that the conservation of α-1,6-linked mannan in fungi of the Zygomycota and Ascomycota can be exploited as a broad diagnostic target and (ii) have provided a means to detect that target in an immunoassay platform that is well suited for clinic or field use. IMPORTANCE A key question asked when faced with an infection, an infestation, or environmental damage is whether it is a fungus. Identification of fungi as the cause of the problem can lead to remediation or treatment. Zygomycetes and ascomycetes account for the vast majority of fungal causes of human, animal, and plant disease, large-scale biodiversity loss, agricultural spoilage, and contamination of water-damaged buildings. These studies revealed the conservation of a common cell wall structural component of zygomycetes and ascomycetes to be a diagnostic target applicable to multiple pathogenic fungi and have leveraged that insight for practical use. Monoclonal antibodies reactive with this pan-fungal structure were produced and used to construct immunoassays (including ELISA and lateral flow assay) for detection of a broad range of pathogenic fungi. Copyright © 2018 Burnham-Marusich et al.

Isolation of Cryptococcus neoformans and other opportunistic fungi from pigeon droppings

PubMed Central

Soltani, Maryam; Bayat, Mansour; Hashemi, Seyed J.; Zia, Mohammadali; Pestechian, Nader

2013-01-01

Background: Invasive fungal infections cause considerable morbidity and mortality in immunocompromised hosts. Pigeon droppings could especially be a potential carrier in the spread of pathogenic yeasts and mold fungi into the environment. The objective of this study was to isolation of Cryptococcus neoformans and other opportunistic fungi from pigeon droppings. Materials and Methods: One hundred twenty samples of pigeon droppings were suspended 1:10 in saline solution and then cultured. Identification of C. neoformans was performed on bird seed agar, presence of a capsule on India ink preparation, urease production on urea agar medium and RapID yeast plus system. The identification of candida species was based on micro-morphological analysis on corn meal-Tween 80 agar, RapID yeast plus system and growth in CHROMagar candida. The identification of other fungi was based on macromorphologic, microscopic, biochemical and physiological characteristics. Results: The highest frequency of yeasts and mold fungi were observed in Candida albicans 6.6% and Penicillium spp. 25%. The frequency rate of C. neoformans isolation was 2.5%. Conclusion: Several types of fungi are present in pigeon droppings that can spread in environment and transmit to children and elderly as well as immunocompromised patients who are at increased risk of contracting opportunistic diseases. PMID:23901339

An overview of antifungal peptides derived from insect.

PubMed

Faruck, Mohammad Omer; Yusof, Faridah; Chowdhury, Silvia

2016-06-01

Fungi are not classified as plants or animals. They resemble plants in many ways but do not produce chlorophyll or make their own food photosynthetically like plants. Fungi are useful for the production of beer, bread, medicine, etc. More complex than viruses or bacteria; fungi can be destructive human pathogens responsible for various diseases in humans. Most people have a strong natural immunity against fungal infection. However, fungi can cause diseases when this immunity breaks down. In the last few years, fungal infection has increased strikingly and has been accompanied by a rise in the number of deaths of cancer patients, transplant recipients, and acquired immunodeficiency syndrome (AIDS) patients owing to fungal infections. The growth rate of fungi is very slow and quite difficult to identify. A series of molecules with antifungal activity against different strains of fungi have been found in insects, which can be of great importance to tackle human diseases. Insects secrete such compounds, which can be peptides, as a part of their immune defense reactions. Active antifungal peptides developed by insects to rapidly eliminate infectious pathogens are considered a component of the defense munitions. This review focuses on naturally occurring antifungal peptides from insects and their challenges to be used as armaments against human diseases. Copyright © 2015 Elsevier Inc. All rights reserved.