Using plate counting and ergosterol assay, single and joint effects of acetochlor and methamidophos on the dynamicsof soil fungal population and total fungal biomass in the black soil zone of Northeast China were inve...Using plate counting and ergosterol assay, single and joint effects of acetochlor and methamidophos on the dynamicsof soil fungal population and total fungal biomass in the black soil zone of Northeast China were investigated. The resultsdemonstrated that acetochlor at high concentration levels (150 and 250 mg kg-1) had an acute and mostly chronic toxicityon both the soil fungal population and total fungal biomass, but at a low concentration (50 mg kg-1) generally had astimulating effect that was stronger with total fungal biomass than with the soil fungal population. Methamidophos ata high concentration level (250 mg kg-1) alone and almost all of its combinations with various dosages of acetochlorincreased the soil fungal population, whereas at most sampling dates with 250 mg methamidophos kg-1 soil, total fungalbiomass increased, but in combination with acetochlor it was decreased in the early period of incubation and then increased28 days after incubation. Thus, through measuring the number of colony forming unit of the soil fungal population alongwith the total fungal biomass, a better understanding on effects of agrochemicals on soil fungi could be made.展开更多
Abstraet: Phlebopus portentosus (Berk. and Broome) Boedijn is a favored wild edible mushroom in the Xishuangbanna region, Yunnan, China and Northern Thailand. It belongs to Boletinellaceae family and is known as "...Abstraet: Phlebopus portentosus (Berk. and Broome) Boedijn is a favored wild edible mushroom in the Xishuangbanna region, Yunnan, China and Northern Thailand. It belongs to Boletinellaceae family and is known as "black bolete". Its ecological habits and biotrophy are very complicated. It can be saprobic and successfully cultivated in mushroom house conditions. More often it grows closely with many plants, but is not mycorrhizal fungus. It forms a tripartite association with root mealy bugs and plants. The fungus produces special fungus-insect gall with the soil mealy bugs, which is a symbiotic association between these two creatures. The gall grows on plant roots with parasitic tendency. This paper is a compact report of the findings, including taxonomy, ecology, economic and cultivation of this mushroom.展开更多
This study focused on the identification of the filamentous fungi associated with soapstone samples exposed to outdoor conditions and the biocidal effect of gamma radiations on isolated fungal populations in Minas Ger...This study focused on the identification of the filamentous fungi associated with soapstone samples exposed to outdoor conditions and the biocidal effect of gamma radiations on isolated fungal populations in Minas Gerais State in Brazil. Two soapstone blocks were placed outdoors under tropical environmental conditions for 12 months. A total of 9 filamentous fungal populations were identified on their surfaces, namely Acremomium (cf.) alternatum, Alternaria alternata, Aspergillusfumigatus, Calcarisporium (cf.) arbuscula, Cladosporium cladosporioides, Curvularia lunata, Epicoccum nigrum, Fusarium equiseti and Penicillium citrinum. The gamma radiation assay was then carried out as a test of biocidal action by exposing all fungal populations to the ionizing radiation. The results showed that only the C. cladosporioides species was resistant to this biocidal agent, since it was able to increase its population post exposure. Scanning electron microscopy images identified the microbial colonization on the soapstone blocks and the stone elementar composition was analyzed by energy dispersive X-ray spectrometry. After treatment, there was no structural and aesthetic alteration in the soapstone samples, and evidencing that gamma radiation can be used as a biocidal agent. However, the resistance of the black fungal population indicates caution in the choice of gamma irradiation as biocidal treatment.展开更多
Cultural practices, hand collection of larvae, light traps and entomopathogenic fungi were investigated to manage of palm borers Oryctes spp. in date palm orchards during the years 2010-2015. Cultural practices, such ...Cultural practices, hand collection of larvae, light traps and entomopathogenic fungi were investigated to manage of palm borers Oryctes spp. in date palm orchards during the years 2010-2015. Cultural practices, such as sanitation and pruning frond bases, hand collection of larvae during regular annual service work and light traps with solar energy were practiced annually in one orchard for five years. In the second orchard, cultural practices were applied for two years, light trap for one year only, and no hand collection of larvae was done during the period. The third orchard was used as a control treatment. Results showed reduction in population density of larvae (91.6% and 53.0%) and adult (76.1% and 41.1%) ofOryects spp. in the 1st and 2nd orchard, respectively The results also demonstrated the impact of moon light phases on the number of Oryctes spp. adults caught by light trap and the existence of an inverse relation between moon light and flight activity of adults. Biological experiments also revealed that entomopathogenic fungi can cause high mortality rate reaching 100% after 29 d. Beauveria bassiana scored higher mortality rate in short time, especially at concentration of 1 × 10^11 conidia/mL with LT50 = 12.75 and LT90 = 20; while, Metarhizium anisopliae caused the higher percentage of malformed adults. The results depicted the effectiveness of some integrated ecological sound control methods for monitoring and population suppression of Oryects spp. in date palm orchards.展开更多
Aims Bacteria and fungi are two primary groups of soil microbes,and their stability determines the persistence of microbial functions in response to a changing environment.Recent studies reported higher fungal than ba...Aims Bacteria and fungi are two primary groups of soil microbes,and their stability determines the persistence of microbial functions in response to a changing environment.Recent studies reported higher fungal than bacterial stability under precipitation alteration,the underlying mechanisms,however,remain elusive.Methods A 3-year precipitation manipulation experiment in a semi-arid grassland was used to compare the bacterial and fungal diversities,including alpha diversity,beta diversity and microbial community composition turnover,in response to precipitation manipulations.A framework is proposed to understand the stability properties of bacteria and fungi under precipitation alteration.We conceived a diagrammatic valley to illustrate microbial stability with the depth representing resistance and the width ecological resilience.Important Findings We found that±60%in precipitation significantly reduced the richness and increased the evenness of bacteria but had trivial impacts on fungi.Precipitation alteration yielded stronger impacts on the variation in alpha diversity of bacteria than fungi,suggesting that the bacterial community is more sensitive to water stress than the fungal community.Moreover,fungi had wider composition turnover than that of bacteria,indicating higher composition variation of fungi than bacteria.The population turnover of fungi,reflected by composition variation,coefficient variation of diversity index and composition turnover,was larger than that of bacteria at both temporal and spatial scales,indicating the population turnover promotes fungal stability.The higher stability of fungal community in tolerating water stress is analogous to a ball in a wide valley that swing substantially but remain close to its steady state;while the lower stability of bacteria community is analogous to a ball that swings slightly but stay far away from its steady state.Our finding that the fungal community had higher stability than bacterial community in a semi-arid grassland might be applicable to other biomes.展开更多
Over the last three decades, the presence and functional roles of arbuscular mycorrhizal (AM) fungi in wetland habitats have received increasing attention. This review summarized the mycorrhizal status in wetlands a...Over the last three decades, the presence and functional roles of arbuscular mycorrhizal (AM) fungi in wetland habitats have received increasing attention. This review summarized the mycorrhizal status in wetlands and the effect of flooding on AM fungal colonization. Plants of 99 families living in 31 different habitats have been found to be associated with AM fungi, even including submerged aquatic plants and several plant species that were thought to be nonmycorrhizal (Cyperaceae, Chenopodiaceae, and Plumbaginaceac). The functions of AM fungi in wetland ecological systems could be concluded as their influences on the composition, succession, and diversity of the wetland plant community, and the growth and nutrition of wetland plants. Affecting the composition, succession, and diversity of the wetland plant community, AM fungi have positive, negative, or neutral effects on the performance of different wetland species under different conditions. The factors that affect the application effect of AM fungi in constructed wetland (CW) include flooding, phosphorus, plant species, aerenchyma, salinity, CW types, operation modes of CW, and wastewater quality. The generalist AM fungi strains can be established spontaneously, rapidly, and extensively in wastewater bioremediation technical installations; therefore, AM fungi can be considered ideal inhabitants of technical installations for the plant-based bioremediation of groundwater contaminated by organic pollutants or other contaminants. In the future, roles of AM fungi and factors that affect the purifying capacity of AM-CW system must be understood to optimize CW ecosystem.展开更多
Fungi play important roles in ecosystem processes, and the elevational pattern of fungal diversity is still unclear. Here, we examined the diversity of fungi along a 1,000 m elevation gradient on Mount Nadu, Southwest...Fungi play important roles in ecosystem processes, and the elevational pattern of fungal diversity is still unclear. Here, we examined the diversity of fungi along a 1,000 m elevation gradient on Mount Nadu, Southwestern China. We used MiSeq sequencing to obtain fungal sequences that were clustered into operational taxonomic units(OTUs) and to measure the fungal composition and diversity. Though the species richness and phylogenetic diversity of the fungal community did not exhibit significant trends with increasing altitude, they were significantly lower at mid-altitudinal sites than at the base. The Bray-Curtis distance clustering also showed that the fungal communities varied significantly with altitude. A distance-based linear model multivariate analysis(DistLM) identified that soil pH dominated the explanatory power of the species richness(23.72%),phylogenetic diversity(24.25%) and beta diversity(28.10%) of the fungal community. Moreover, the species richness and phylogenetic diversity of the fungal community increased linearly with increasing soil pH(P<0.05). Our study provides evidence that pH is an important predictor of soil fungal diversity along elevation gradients in Southwestern China.展开更多
Functional response is a key index in determining the population fluctuation in predation. However, the lack of operable research system limits the studies on functional response of fungal predators. Hirsutella rhossi...Functional response is a key index in determining the population fluctuation in predation. However, the lack of operable research system limits the studies on functional response of fungal predators. Hirsutella rhossiliensis is a dominant parasite of the soybean cyst nematode, Heterodera glycines. In a soil microcosm bioassay, we determined fungal biomass at different days within 21 days after inoculation, and parasitism rate of H. glycines by the fungus was determined. The functional response of H. rhossiliensis to H. glycines was established and found to be Holling's type Ill, which was influenced by mycelial densities. Meanwhile, we conducted anti-fungal analysis of metabolic fractions extracted from H. rhossiliensis to explain the potential mechanism of the intraspecific competition illustrated by functional response. The result of anti-fungal experiments indicated that the fungal predators had more complicated interaction at population level than expected, which might be regulated by self-inhibition metabolite(s). This study was the first functional response study of fungal predators in microcosm. With the in- creasing recognition of emerging fungal threats to animal, plant, and ecosystem health, the methodologies and hypotheses proposed in this study might inspire further research in fungal ecology.展开更多
基金the National Key Basic Research Support Foundation of China (No. 2004CB418503), the NationalScience Fund for Distinguished Young Scholars (No. 20225722) and the Innovation Project of the Institute of AppliedEcology, Chinese Academy of Sciences (No. C12SFSLYQY0402).
文摘Using plate counting and ergosterol assay, single and joint effects of acetochlor and methamidophos on the dynamicsof soil fungal population and total fungal biomass in the black soil zone of Northeast China were investigated. The resultsdemonstrated that acetochlor at high concentration levels (150 and 250 mg kg-1) had an acute and mostly chronic toxicityon both the soil fungal population and total fungal biomass, but at a low concentration (50 mg kg-1) generally had astimulating effect that was stronger with total fungal biomass than with the soil fungal population. Methamidophos ata high concentration level (250 mg kg-1) alone and almost all of its combinations with various dosages of acetochlorincreased the soil fungal population, whereas at most sampling dates with 250 mg methamidophos kg-1 soil, total fungalbiomass increased, but in combination with acetochlor it was decreased in the early period of incubation and then increased28 days after incubation. Thus, through measuring the number of colony forming unit of the soil fungal population alongwith the total fungal biomass, a better understanding on effects of agrochemicals on soil fungi could be made.
基金Sincere thanks to Toni Atkinson for her editing of the paper. This study was supported by the Key Project of Applied Basic Research of Yunnan Province (No. 2017FA017), the Funds of Sci-Tech Innovation System Construction for Tropical Crops of Yunnan Province (No. RF2017-10), the Special Fund of Technological Development for Yunnan Institutions (No. 2015DC014), the National Natural Science Foundation of China (No. 31560008) and "Western Light"--Personnel Training Project of the Chinese Academy of Sciences (No. 326). This study was also supported by the New Zealand Institute for Plant & Food Research Ltd..
文摘Abstraet: Phlebopus portentosus (Berk. and Broome) Boedijn is a favored wild edible mushroom in the Xishuangbanna region, Yunnan, China and Northern Thailand. It belongs to Boletinellaceae family and is known as "black bolete". Its ecological habits and biotrophy are very complicated. It can be saprobic and successfully cultivated in mushroom house conditions. More often it grows closely with many plants, but is not mycorrhizal fungus. It forms a tripartite association with root mealy bugs and plants. The fungus produces special fungus-insect gall with the soil mealy bugs, which is a symbiotic association between these two creatures. The gall grows on plant roots with parasitic tendency. This paper is a compact report of the findings, including taxonomy, ecology, economic and cultivation of this mushroom.
文摘This study focused on the identification of the filamentous fungi associated with soapstone samples exposed to outdoor conditions and the biocidal effect of gamma radiations on isolated fungal populations in Minas Gerais State in Brazil. Two soapstone blocks were placed outdoors under tropical environmental conditions for 12 months. A total of 9 filamentous fungal populations were identified on their surfaces, namely Acremomium (cf.) alternatum, Alternaria alternata, Aspergillusfumigatus, Calcarisporium (cf.) arbuscula, Cladosporium cladosporioides, Curvularia lunata, Epicoccum nigrum, Fusarium equiseti and Penicillium citrinum. The gamma radiation assay was then carried out as a test of biocidal action by exposing all fungal populations to the ionizing radiation. The results showed that only the C. cladosporioides species was resistant to this biocidal agent, since it was able to increase its population post exposure. Scanning electron microscopy images identified the microbial colonization on the soapstone blocks and the stone elementar composition was analyzed by energy dispersive X-ray spectrometry. After treatment, there was no structural and aesthetic alteration in the soapstone samples, and evidencing that gamma radiation can be used as a biocidal agent. However, the resistance of the black fungal population indicates caution in the choice of gamma irradiation as biocidal treatment.
文摘Cultural practices, hand collection of larvae, light traps and entomopathogenic fungi were investigated to manage of palm borers Oryctes spp. in date palm orchards during the years 2010-2015. Cultural practices, such as sanitation and pruning frond bases, hand collection of larvae during regular annual service work and light traps with solar energy were practiced annually in one orchard for five years. In the second orchard, cultural practices were applied for two years, light trap for one year only, and no hand collection of larvae was done during the period. The third orchard was used as a control treatment. Results showed reduction in population density of larvae (91.6% and 53.0%) and adult (76.1% and 41.1%) ofOryects spp. in the 1st and 2nd orchard, respectively The results also demonstrated the impact of moon light phases on the number of Oryctes spp. adults caught by light trap and the existence of an inverse relation between moon light and flight activity of adults. Biological experiments also revealed that entomopathogenic fungi can cause high mortality rate reaching 100% after 29 d. Beauveria bassiana scored higher mortality rate in short time, especially at concentration of 1 × 10^11 conidia/mL with LT50 = 12.75 and LT90 = 20; while, Metarhizium anisopliae caused the higher percentage of malformed adults. The results depicted the effectiveness of some integrated ecological sound control methods for monitoring and population suppression of Oryects spp. in date palm orchards.
基金supported by the Chinese National Key Development Program for Basic Research(grant no.2017YFA0604802 and 2016YFC0500703)National Natural Science Foundation of China(grant no.31770526 and 41573063)+1 种基金Strategic Priority Research Program on Soil and Microbes of the Chinese Academy of Sciences(grant no.XDB15010401)Key Laboratory of Vegetation Ecology,Ministry of Education.X.X.acknowledges the financial support from the San Diego State University and the CSU Program for Education&Research in Biotechnology.
文摘Aims Bacteria and fungi are two primary groups of soil microbes,and their stability determines the persistence of microbial functions in response to a changing environment.Recent studies reported higher fungal than bacterial stability under precipitation alteration,the underlying mechanisms,however,remain elusive.Methods A 3-year precipitation manipulation experiment in a semi-arid grassland was used to compare the bacterial and fungal diversities,including alpha diversity,beta diversity and microbial community composition turnover,in response to precipitation manipulations.A framework is proposed to understand the stability properties of bacteria and fungi under precipitation alteration.We conceived a diagrammatic valley to illustrate microbial stability with the depth representing resistance and the width ecological resilience.Important Findings We found that±60%in precipitation significantly reduced the richness and increased the evenness of bacteria but had trivial impacts on fungi.Precipitation alteration yielded stronger impacts on the variation in alpha diversity of bacteria than fungi,suggesting that the bacterial community is more sensitive to water stress than the fungal community.Moreover,fungi had wider composition turnover than that of bacteria,indicating higher composition variation of fungi than bacteria.The population turnover of fungi,reflected by composition variation,coefficient variation of diversity index and composition turnover,was larger than that of bacteria at both temporal and spatial scales,indicating the population turnover promotes fungal stability.The higher stability of fungal community in tolerating water stress is analogous to a ball in a wide valley that swing substantially but remain close to its steady state;while the lower stability of bacteria community is analogous to a ball that swings slightly but stay far away from its steady state.Our finding that the fungal community had higher stability than bacterial community in a semi-arid grassland might be applicable to other biomes.
基金supported by the National Natural Science Foundation of China (Nos. 31400435 and 31270573)the Fundamental Research Funds for the Central Universities of China (No. WUT2014-IV-050)the Natural Science Foundation of Hubei Province, China (No. 2015CFB596)
文摘Over the last three decades, the presence and functional roles of arbuscular mycorrhizal (AM) fungi in wetland habitats have received increasing attention. This review summarized the mycorrhizal status in wetlands and the effect of flooding on AM fungal colonization. Plants of 99 families living in 31 different habitats have been found to be associated with AM fungi, even including submerged aquatic plants and several plant species that were thought to be nonmycorrhizal (Cyperaceae, Chenopodiaceae, and Plumbaginaceac). The functions of AM fungi in wetland ecological systems could be concluded as their influences on the composition, succession, and diversity of the wetland plant community, and the growth and nutrition of wetland plants. Affecting the composition, succession, and diversity of the wetland plant community, AM fungi have positive, negative, or neutral effects on the performance of different wetland species under different conditions. The factors that affect the application effect of AM fungi in constructed wetland (CW) include flooding, phosphorus, plant species, aerenchyma, salinity, CW types, operation modes of CW, and wastewater quality. The generalist AM fungi strains can be established spontaneously, rapidly, and extensively in wastewater bioremediation technical installations; therefore, AM fungi can be considered ideal inhabitants of technical installations for the plant-based bioremediation of groundwater contaminated by organic pollutants or other contaminants. In the future, roles of AM fungi and factors that affect the purifying capacity of AM-CW system must be understood to optimize CW ecosystem.
基金supported by the National Natural Science Foundation of China(41071039)the Ministry of Science and Technology of China(2012CB417103)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA05060100)
文摘Fungi play important roles in ecosystem processes, and the elevational pattern of fungal diversity is still unclear. Here, we examined the diversity of fungi along a 1,000 m elevation gradient on Mount Nadu, Southwestern China. We used MiSeq sequencing to obtain fungal sequences that were clustered into operational taxonomic units(OTUs) and to measure the fungal composition and diversity. Though the species richness and phylogenetic diversity of the fungal community did not exhibit significant trends with increasing altitude, they were significantly lower at mid-altitudinal sites than at the base. The Bray-Curtis distance clustering also showed that the fungal communities varied significantly with altitude. A distance-based linear model multivariate analysis(DistLM) identified that soil pH dominated the explanatory power of the species richness(23.72%),phylogenetic diversity(24.25%) and beta diversity(28.10%) of the fungal community. Moreover, the species richness and phylogenetic diversity of the fungal community increased linearly with increasing soil pH(P<0.05). Our study provides evidence that pH is an important predictor of soil fungal diversity along elevation gradients in Southwestern China.
基金supported by the National Key Basic Research Program of China(2013CB127506)the National Natural Science Foundation of China(30800732)the National Public Benefit Research Foundation of China(200903040)
文摘Functional response is a key index in determining the population fluctuation in predation. However, the lack of operable research system limits the studies on functional response of fungal predators. Hirsutella rhossiliensis is a dominant parasite of the soybean cyst nematode, Heterodera glycines. In a soil microcosm bioassay, we determined fungal biomass at different days within 21 days after inoculation, and parasitism rate of H. glycines by the fungus was determined. The functional response of H. rhossiliensis to H. glycines was established and found to be Holling's type Ill, which was influenced by mycelial densities. Meanwhile, we conducted anti-fungal analysis of metabolic fractions extracted from H. rhossiliensis to explain the potential mechanism of the intraspecific competition illustrated by functional response. The result of anti-fungal experiments indicated that the fungal predators had more complicated interaction at population level than expected, which might be regulated by self-inhibition metabolite(s). This study was the first functional response study of fungal predators in microcosm. With the in- creasing recognition of emerging fungal threats to animal, plant, and ecosystem health, the methodologies and hypotheses proposed in this study might inspire further research in fungal ecology.