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Nguyen TP, Meng DR, Chang CH, Su PY, Ou CA, Hou PF, Sung HM, Chou CH, Ohme-Takagi M, Huang HJ. Antifungal mechanism of volatile compounds emitted by Actinomycetota Paenarthrobacter ureafaciens from a disease-suppressive soil on Saccharomyces cerevisiae. mSphere 2023; 8:e0032423. [PMID: 37750721 PMCID: PMC10597458 DOI: 10.1128/msphere.00324-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Accepted: 08/07/2023] [Indexed: 09/27/2023] Open
Abstract
Increasing evidence suggests that in disease-suppressive soils, microbial volatile compounds (mVCs) released from bacteria may inhibit the growth of plant-pathogenic fungi. However, the antifungal activities and molecular responses of fungi to different mVCs remain largely undescribed. In this study, we first evaluated the responses of pathogenic fungi to treatment with mVCs from Paenarthrobacter ureafaciens. Then, we utilized the well-characterized fungal model organism Saccharomyces cerevisiae to study the potential mechanistic effects of the mVCs. Our data showed that exposure to P. ureafaciens mVCs leads to reduced growth of several pathogenic fungi, and in yeast cells, mVC exposure prompts the accumulation of reactive oxygen species. Further experiments with S. cerevisiae deletion mutants indicated that Slt2/Mpk1 and Hog1 MAPKs play major roles in the yeast response to P. ureafaciens mVCs. Transcriptomic analysis revealed that exposure to mVCs was associated with 1,030 differentially expressed genes (DEGs) in yeast. According to gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses, many of these DEGs are involved in mitochondrial dysfunction, cell integrity, mitophagy, cellular metabolism, and iron uptake. Genes encoding antimicrobial proteins were also significantly altered in the yeast after exposure to mVCs. These findings suggest that oxidative damage and mitochondrial dysfunction are major contributors to the fungal toxicity of mVCs. Furthermore, our data showed that cell wall, antioxidant, and antimicrobial defenses are induced in yeast exposed to mVCs. Thus, our findings expand upon previous research by delineating the transcriptional responses of the fungal model. IMPORTANCE Since the use of bacteria-emitted volatile compounds in phytopathogen control is of considerable interest, it is important to understand the molecular mechanisms by which fungi may adapt to microbial volatile compounds (mVCs). Paenarthrobacter ureafaciens is an isolated bacterium from disease-suppressive soil that belongs to the Actinomycetota phylum. P. ureafaciens mVCs showed a potent antifungal effect on phytopathogens, which may contribute to disease suppression in soil. However, our knowledge about the antifungal mechanism of mVCs is limited. This study has proven that mVCs are toxic to fungi due to oxidative stress and mitochondrial dysfunction. To deal with mVC toxicity, antioxidants and physical defenses are required. Furthermore, iron uptake and CAP proteins are required for antimicrobial defense, which is necessary for fungi to deal with the thread from mVCs. This study provides essential foundational knowledge regarding the molecular responses of fungi to inhibitory mVCs.
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Affiliation(s)
- Tri-Phuong Nguyen
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
| | - De-Rui Meng
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Ching-Han Chang
- Graduate Program in Translational Agricultural Sciences, National Cheng Kung University and Academia Sinica, Tainan, Taiwan
| | - Pei-Yu Su
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Chieh-An Ou
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Ping-Fu Hou
- Kaohsiung District Agricultural Research and Extension Station, Pingtung, Taiwan
| | - Huang-Mo Sung
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Chang-Hung Chou
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Masaru Ohme-Takagi
- Institute of Tropical Plant Sciences and Microbiology, National Cheng Kung University, Tainan, Taiwan
| | - Hao-Jen Huang
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
- Graduate Program in Translational Agricultural Sciences, National Cheng Kung University and Academia Sinica, Tainan, Taiwan
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Vivelo S, Alsairafi B, Walsh JT, Bhatnagar JM. Intrinsic growth rate and cellobiohydrolase activity underlie the phylogenetic signal to fungal decomposer succession. FUNGAL ECOL 2023. [DOI: 10.1016/j.funeco.2022.101180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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3
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Durán P, Tortella G, Sadowsky MJ, Viscardi S, Barra PJ, Mora MDLL. Engineering Multigenerational Host-Modulated Microbiota against Soilborne Pathogens in Response to Global Climate Change. BIOLOGY 2021; 10:865. [PMID: 34571742 PMCID: PMC8472835 DOI: 10.3390/biology10090865] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/26/2021] [Accepted: 08/27/2021] [Indexed: 11/17/2022]
Abstract
Crop migration caused by climatic events has favored the emergence of new soilborne diseases, resulting in the colonization of new niches (emerging infectious diseases, EIDs). Soilborne pathogens are extremely persistent in the environment. This is in large part due to their ability to reside in the soil for a long time, even without a host plant, using survival several strategies. In this regard, disease-suppressive soils, characterized by a low disease incidence due to the presence of antagonist microorganisms, can be an excellent opportunity for the study mechanisms of soil-induced immunity, which can be applied in the development of a new generation of bioinoculants. Therefore, here we review the main effects of climate change on crops and pathogens, as well as the potential use of soil-suppressive microbiota as a natural source of biocontrol agents. Based on results of previous studies, we also propose a strategy for the optimization of microbiota assemblages, selected using a host-mediated approach. This process involves an increase in and prevalence of specific taxa during the transition from a conducive to a suppressive soil. This strategy could be used as a model to engineer microbiota assemblages for pathogen suppression, as well as for the reduction of abiotic stresses created due to global climate change.
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Affiliation(s)
- Paola Durán
- Scientific and Technological Bioresource Nucleus, Universidad de La Frontera, Temuco 4811230, Chile; (P.J.B.); (M.d.l.L.M.)
- Biocontrol Research Laboratory, Universidad de La Frontera, Temuco 4811230, Chile
| | - Gonzalo Tortella
- Centro de Excelencia en Investigación Biotecnológica Aplicada al Medio Ambiente (CIBAMA-BIOREN), Facultad de Ingeniería y Ciencias, Universidad de La Frontera, Temuco 4811230, Chile;
| | - Michael J. Sadowsky
- BioTechnology Institute, University of Minnesota, Minneapolis, MN 55108, USA;
| | - Sharon Viscardi
- Núcleo de Investigación en Producción Alimentaria, Facultad de Recursos Naturales, Universidad Católica de Temuco, P.O. Box 15-D, Temuco 4813302, Chile;
| | - Patricio Javier Barra
- Scientific and Technological Bioresource Nucleus, Universidad de La Frontera, Temuco 4811230, Chile; (P.J.B.); (M.d.l.L.M.)
- Biocontrol Research Laboratory, Universidad de La Frontera, Temuco 4811230, Chile
| | - Maria de la Luz Mora
- Scientific and Technological Bioresource Nucleus, Universidad de La Frontera, Temuco 4811230, Chile; (P.J.B.); (M.d.l.L.M.)
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4
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Clocchiatti A, Hannula SE, Rizaludin MS, Hundscheid MPJ, klein Gunnewiek PJA, Schilder MT, Postma J, de Boer W. Impact of Cellulose-Rich Organic Soil Amendments on Growth Dynamics and Pathogenicity of Rhizoctonia solani. Microorganisms 2021; 9:microorganisms9061285. [PMID: 34204724 PMCID: PMC8231496 DOI: 10.3390/microorganisms9061285] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 05/25/2021] [Accepted: 06/03/2021] [Indexed: 01/04/2023] Open
Abstract
Cellulose-rich amendments stimulate saprotrophic fungi in arable soils. This may increase competitive and antagonistic interactions with root-infecting pathogenic fungi, resulting in lower disease incidence. However, cellulose-rich amendments may also stimulate pathogenic fungi with saprotrophic abilities, thereby increasing plant disease severity. The current study explores these scenarios, with a focus on the pathogenic fungus Rhizoctonia solani. Saprotrophic growth of R. solani on cellulose-rich materials was tested in vitro. This confirmed paper pulp as a highly suitable substrate for R. solani, whereas its performance on wood sawdusts varied with tree species. In two pot experiments, the effects of amendment of R. solani-infected soil with cellulose-rich materials on performance of beetroot seedlings were tested. All deciduous sawdusts and paper pulp stimulated soil fungal biomass, but only oak, elder and beech sawdusts reduced damping-off of beetroot. Oak sawdust amendment gave a consistent stimulation of saprotrophic Sordariomycetes fungi and of seedling performance, independently of the time between amendment and sowing. In contrast, paper pulp caused a short-term increase in R. solani abundance, coinciding with increased disease severity for beet seedlings sown immediately after amendment. However, damping-off of beetroot was reduced if plants were sown two or four weeks after paper pulp amendment. Cellulolytic bacteria, including Cytophagaceae, responded to paper pulp during the first two weeks and may have counteracted further spread of R. solani. The results showed that fungus-stimulating, cellulose-rich amendments have potential to be used for suppression of R. solani. However, such amendments require a careful consideration of material choice and application strategy.
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Affiliation(s)
- Anna Clocchiatti
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), 6708 PB Wageningen, The Netherlands; (M.S.R.); (M.P.J.H.); (P.J.A.k.G.)
- Correspondence: (A.C.); (W.d.B.)
| | - Silja Emilia Hannula
- Department of Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), 6708 PB Wageningen, The Netherlands;
| | - Muhammad Syamsu Rizaludin
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), 6708 PB Wageningen, The Netherlands; (M.S.R.); (M.P.J.H.); (P.J.A.k.G.)
| | - Maria P. J. Hundscheid
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), 6708 PB Wageningen, The Netherlands; (M.S.R.); (M.P.J.H.); (P.J.A.k.G.)
| | - Paulien J. A. klein Gunnewiek
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), 6708 PB Wageningen, The Netherlands; (M.S.R.); (M.P.J.H.); (P.J.A.k.G.)
| | - Mirjam T. Schilder
- Biointeractions and Plant Health, Wageningen University & Research, 6708 PB Wageningen, The Netherlands; (M.T.S.); (J.P.)
| | - Joeke Postma
- Biointeractions and Plant Health, Wageningen University & Research, 6708 PB Wageningen, The Netherlands; (M.T.S.); (J.P.)
| | - Wietse de Boer
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), 6708 PB Wageningen, The Netherlands; (M.S.R.); (M.P.J.H.); (P.J.A.k.G.)
- Soil Biology Group, Wageningen University, 6708 PB Wageningen, The Netherlands
- Correspondence: (A.C.); (W.d.B.)
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De Corato U. Agricultural waste recycling in horticultural intensive farming systems by on-farm composting and compost-based tea application improves soil quality and plant health: A review under the perspective of a circular economy. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 738:139840. [PMID: 32531600 DOI: 10.1016/j.scitotenv.2020.139840] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 05/28/2020] [Accepted: 05/28/2020] [Indexed: 05/08/2023]
Abstract
The vegetables supply chain of intensive farming systems has gained huge relevance due to environmental pollution, residual toxicity towards microorganisms and humans, development of plant pathogen resistance, biodiversity loss, and hazard to human health. Studies addressed to clean from misuse of plant fungicides, soil fumigants, and fertilizers have encouraged the search of eco-friendly alternatives. This paper aims to give deeper understand of new insights for on-farm composting and compost-based tea application for soil and plant through the virtuous reuse of agricultural waste. On-farm composting is viable option thanks to benefits on soil quality and plant health which valorize underused biomass. This paper critically discusses and compares the most promising technologies in order to recycle in situ residual biomass into high-value added products for soil amendment (compost) and plant treatment (compost-based tea). Compost contains minerals, heavy metals, humic substances, and endogenous microorganisms to improve soil quality. Compost application had many benefits against plant pathogens and diseases due to innovative tailored formulates. Compost can be employed either alone or in combination with exogenous microbial consortia (protists, fungi, oomycetes, yeast, actinomycetes, and bacteria) acting as biological control agents by fitting the agrochemical market requirements for improving soil quality and plant health. Liquid formulations made of crude compost-based teas and/or tailored mixtures of humic acids, fulvic acids, humin, macro-micronutrients, and endogenous microbiota have many benefits for plant growth and crop health. Nonetheless, the complex European regulations and national laws, manure surplus, variability in availability and transporting of compost, variability in compost quality and feedstock composition, greenhouse gas emissions, and energy requirement were very hard barriers for on-farm composting and compost derivatives application. Recommendations, novelties, innovations, sustainability, and directions of future researches that may help to solve a number of these issues under the new perspective of a circular economy system were presented and discussed.
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Affiliation(s)
- Ugo De Corato
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Department of Bioenergy, Biorefinery and Green Chemistry (DTE-BBC-BIC), Territorial Office of Bari, Via Giulio Petroni 15/F, Bari 70124, Italy.
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6
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de Boer W, Li X, Meisner A, Garbeva P. Pathogen suppression by microbial volatile organic compounds in soils. FEMS Microbiol Ecol 2020; 95:5527321. [PMID: 31265069 DOI: 10.1093/femsec/fiz105] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 06/30/2019] [Indexed: 12/15/2022] Open
Abstract
There is increasing evidence that microbial volatile organic compounds (mVOCs) play an important role in interactions between microbes in soils. In this minireview, we zoom in on the possible role of mVOCs in the suppression of plant-pathogenic soil fungi. In particular, we have screened the literature to see what the actual evidence is that mVOCs in soil atmospheres can contribute to pathogen suppression. Furthermore, we discuss biotic and abiotic factors that influence the production of suppressive mVOCs in soils. Since microbes producing mVOCs in soils are part of microbial communities, community ecological aspects such as diversity and assembly play an important role in the composition of produced mVOC blends. These aspects have not received much attention so far. In addition, the fluctuating abiotic conditions in soils, such as changing moisture contents, influence mVOC production and activity. The biotic and abiotic complexity of the soil environment hampers the extrapolation of the production and suppressing activity of mVOCs by microbial isolates on artificial growth media. Yet, several pathogen suppressive mVOCs produced by pure cultures do also occur in soil atmospheres. Therefore, an integration of lab and field studies on the production of mVOCs is needed to understand and predict the composition and dynamics of mVOCs in soil atmospheres. This knowledge, together with the knowledge of the chemistry and physical behaviour of mVOCs in soils, forms the basis for the development of sustainable management strategies to enhance the natural control of soil-borne pathogens with mVOCs. Possibilities for the mVOC-based control of soil-borne pathogens are discussed.
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Affiliation(s)
- Wietse de Boer
- Department of Microbial Ecology, Netherlands Institute of Ecology, NIOO-KNAW, Droevendaalsesteeg 10, 6708PB Wageningen, The Netherlands.,Soil Biology Group, Wageningen University, Droevendaalsesteeg 3, 6708PB Wageningen, The Netherlands
| | - Xiaogang Li
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Longpan Road 159, 210037 Nanjing, China
| | - Annelein Meisner
- Department of Microbial Ecology, Netherlands Institute of Ecology, NIOO-KNAW, Droevendaalsesteeg 10, 6708PB Wageningen, The Netherlands.,Microbial Ecology, Department of Biology, Lund University, Ecology Building, Sölvegatan 37, SE-22363 Lund, Sweden
| | - Paolina Garbeva
- Department of Microbial Ecology, Netherlands Institute of Ecology, NIOO-KNAW, Droevendaalsesteeg 10, 6708PB Wageningen, The Netherlands
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7
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Assessing the resilience of biodiversity-driven functions in agroecosystems under environmental change. ADV ECOL RES 2019. [DOI: 10.1016/bs.aecr.2019.02.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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8
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Mas MT, Verdú AM. Soil spatial distribution in a smut fungus-annual grass interaction: Exploring patterns to understand disease dynamics at plot scale. FUNGAL ECOL 2018. [DOI: 10.1016/j.funeco.2018.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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9
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Avilés M, Borrero C. Identifying Characteristics of Verticillium Wilt Suppressiveness in Olive Mill Composts. PLANT DISEASE 2017; 101:1568-1577. [PMID: 30677335 DOI: 10.1094/pdis-08-16-1172-re] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The aims of this study were to assess the potential suppressive effects of different olive mill composts on Verticillium wilt and to elucidate the suppressive mechanisms. To this end, four olive mill composts from different crop areas with two maturation levels were selected. After conducting the Verticillium wilt bioassays in cotton, the suppressive effect was observed in only one compost. Compost maturation level did not affect disease development. The standardized area under the disease progress curve and microsclerotia concentration were associated with low API-ZYM enzymatic diversity, β-glucosidase activity, pH, and high electrical conductivity (EC). To assess the nature of suppressiveness in the suppressive compost, additional bioassays were performed with three treated compost-amended growing media (N-supplemented, autoclaved, and heat treated at 60°C for 6 days). Suppressiveness was partially reduced with heat treatments, where N-acetyl-β-glucosaminidase activity disappeared. In this compost, high oligotrophic actinomycete populations were associated with disease reduction. Therefore, plant growth media amended with different olive mill composts do not always show suppressiveness against Verticillium wilt. Enzymatic diversity, β-glucosidase activity, pH, and EC may be sufficient to predict where olive mill compost plant growth media will be effective in reducing Verticillium wilt and microsclerotia concentration. General and specific suppressiveness are involved in the mechanism of compost suppression.
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Affiliation(s)
- Manuel Avilés
- Dept. Ciencias Agroforestales, Escuela Técnica Superior de Ingeniería Agronómica, Universidad de Sevilla, Ctra. Utrera km 1, 41013 Sevilla, Spain
| | - Celia Borrero
- Dept. Ciencias Agroforestales, Escuela Técnica Superior de Ingeniería Agronómica, Universidad de Sevilla, Ctra. Utrera km 1, 41013 Sevilla, Spain
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10
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Ockleford C, Adriaanse P, Berny P, Brock T, Duquesne S, Grilli S, Hernandez-Jerez AF, Bennekou SH, Klein M, Kuhl T, Laskowski R, Machera K, Pelkonen O, Pieper S, Stemmer M, Sundh I, Teodorovic I, Tiktak A, Topping CJ, Wolterink G, Craig P, de Jong F, Manachini B, Sousa P, Swarowsky K, Auteri D, Arena M, Rob S. Scientific Opinion addressing the state of the science on risk assessment of plant protection products for in-soil organisms. EFSA J 2017; 15:e04690. [PMID: 32625401 PMCID: PMC7009882 DOI: 10.2903/j.efsa.2017.4690] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Following a request from EFSA, the Panel on Plant Protection Products and their Residues developed an opinion on the science behind the risk assessment of plant protection products for in-soil organisms. The current risk assessment scheme is reviewed, taking into account new regulatory frameworks and scientific developments. Proposals are made for specific protection goals for in-soil organisms being key drivers for relevant ecosystem services in agricultural landscapes such as nutrient cycling, soil structure, pest control and biodiversity. Considering the time-scales and biological processes related to the dispersal of the majority of in-soil organisms compared to terrestrial non-target arthropods living above soil, the Panel proposes that in-soil environmental risk assessments are made at in- and off-field scale considering field boundary levels. A new testing strategy which takes into account the relevant exposure routes for in-soil organisms and the potential direct and indirect effects is proposed. In order to address species recovery and long-term impacts of PPPs, the use of population models is also proposed.
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Kramer S, Dibbern D, Moll J, Huenninghaus M, Koller R, Krueger D, Marhan S, Urich T, Wubet T, Bonkowski M, Buscot F, Lueders T, Kandeler E. Resource Partitioning between Bacteria, Fungi, and Protists in the Detritusphere of an Agricultural Soil. Front Microbiol 2016; 7:1524. [PMID: 27725815 PMCID: PMC5035733 DOI: 10.3389/fmicb.2016.01524] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 09/12/2016] [Indexed: 01/31/2023] Open
Abstract
The flow of plant-derived carbon in soil is a key component of global carbon cycling. Conceptual models of trophic carbon fluxes in soil have assumed separate bacterial and fungal energy channels in the detritusphere, controlled by both substrate complexity and recalcitrance. However, detailed understanding of the key populations involved and niche-partitioning between them is limited. Here, a microcosm experiment was performed to trace the flow of detritusphere C from substrate analogs (glucose, cellulose) and plant biomass amendments (maize leaves, roots) in an agricultural soil. Carbon flow was traced by rRNA stable isotope probing and amplicon sequencing across three microbial kingdoms. Distinct lineages within the Actinobacteria, Bacteroidetes, Gammaproteobacteria, Basidiomycota, Ascomycota as well as Peronosporomycetes were identified as important primary substrate consumers. A dynamic succession of primary consumers was observed especially in the cellulose treatments, but also in plant amendments over time. While intra-kingdom niche partitioning was clearly observed, distinct bacterial and fungal energy channels were not apparent. Furthermore, while the diversity of primary substrate consumers did not notably increase with substrate complexity, consumer succession and secondary trophic links to bacterivorous and fungivorous microbes resulted in increased food web complexity in the more recalcitrant substrates. This suggests that rather than substrate-defined energy channels, consumer succession as well as intra- and inter-kingdom cross-feeding should be considered as mechanisms supporting food web complexity in the detritusphere.
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Affiliation(s)
- Susanne Kramer
- Institute of Soil Science and Land Evaluation, University of Hohenheim Stuttgart, Germany
| | - Dörte Dibbern
- Institute of Groundwater Ecology, Helmholtz Zentrum München - German Research Center for Environmental Health Neuherberg, Germany
| | - Julia Moll
- Department of Soil Ecology, Helmholtz Centre for Environmental Research Leipzig-HalleHalle, Germany; Institute of Biology, University of LeipzigLeipzig, Germany
| | - Maike Huenninghaus
- Department of Terrestrial Ecology, Institute of Zoology, University of Cologne Köln, Germany
| | - Robert Koller
- Department of Terrestrial Ecology, Institute of Zoology, University of Cologne Köln, Germany
| | - Dirk Krueger
- Department of Soil Ecology, Helmholtz Centre for Environmental Research Leipzig-Halle Halle, Germany
| | - Sven Marhan
- Institute of Soil Science and Land Evaluation, University of Hohenheim Stuttgart, Germany
| | - Tim Urich
- Department of Bacterial Physiology, Institute for Microbiology, Ernst-Moritz-Arndt University of Greifswald Greifswald, Germany
| | - Tesfaye Wubet
- Department of Soil Ecology, Helmholtz Centre for Environmental Research Leipzig-HalleHalle, Germany; German Centre for Integrative Biodiversity Research (iDiv)Leipzig, Germany
| | - Michael Bonkowski
- Department of Terrestrial Ecology, Institute of Zoology, University of Cologne Köln, Germany
| | - François Buscot
- Department of Soil Ecology, Helmholtz Centre for Environmental Research Leipzig-HalleHalle, Germany; Institute of Biology, University of LeipzigLeipzig, Germany; German Centre for Integrative Biodiversity Research (iDiv)Leipzig, Germany
| | - Tillmann Lueders
- Institute of Groundwater Ecology, Helmholtz Zentrum München - German Research Center for Environmental Health Neuherberg, Germany
| | - Ellen Kandeler
- Institute of Soil Science and Land Evaluation, University of Hohenheim Stuttgart, Germany
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Natural Mechanisms of Soil Suppressiveness Against Diseases Caused by Fusarium, Rhizoctonia, Pythium, and Phytophthora. SOIL BIOLOGY 2015. [DOI: 10.1007/978-3-319-23075-7_5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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13
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Mukasa Mugerwa T, Saleeba J, McGee P. A variety of melanised root-associated fungi from the Sydney basin form endophytic associations with Trifolium subterraneum. FUNGAL ECOL 2013. [DOI: 10.1016/j.funeco.2012.08.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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14
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Cross-site soil microbial communities under tillage regimes: fungistasis and microbial biomarkers. Appl Environ Microbiol 2012; 78:8191-201. [PMID: 22983972 DOI: 10.1128/aem.02005-12] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The exploitation of soil ecosystem services by agricultural management strategies requires knowledge of microbial communities in different management regimes. Crop cover by no-till management protects the soil surface, reducing the risk of erosion and nutrient leaching, but might increase straw residue-borne and soilborne plant-pathogenic fungi. A cross-site study of soil microbial communities and Fusarium fungistasis was conducted on six long-term agricultural fields with no-till and moldboard-plowed treatments. Microbial communities were studied at the topsoil surface (0 to 5 cm) and bottom (10 to 20 cm) by general bacterial and actinobacterial terminal restriction fragment length polymorphism (T-RFLP) and phospholipid fatty acid (PLFA) analyses. Fusarium culmorum soil fungistasis describing soil receptivity to plant-pathogenic fungi was explored by using the surface layer method. Soil depth had a significant impact on general bacterial as well as actinobacterial communities and PLFA profiles in no-till treatment, with a clear spatial distinction of communities (P < 0.05), whereas the depth-related separation of microbial communities was not observed in plowed fields. The fungal biomass was higher in no-till surface soil than in plowed soil (P < 0.07). Soil total microbial biomass and fungal biomass correlated with fungistasis (P < 0.02 for the sum of PLFAs; P < 0.001 for PLFA 18:2ω6). Our cross-site study demonstrated that agricultural management strategies can have a major impact on soil microbial community structures, indicating that it is possible to influence the soil processes with management decisions. The interactions between plant-pathogenic fungi and soil microbial communities are multifaceted, and a high level of fungistasis could be linked to the high microbial biomass in soil but not to the specific management strategy.
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Berendsen RL, Kalkhove SIC, Lugones LG, Wösten HAB, Bakker PAHM. Germination of Lecanicillium fungicola in the mycosphere of Agaricus bisporus. ENVIRONMENTAL MICROBIOLOGY REPORTS 2012; 4:227-233. [PMID: 23757277 DOI: 10.1111/j.1758-2229.2011.00325.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Dry bubble disease is a major problem in the commercial cultivation of the white button mushroom Agaricus bisporus and is caused by the ascomycete Lecanicillium fungicola. In the casing layer, germination of L. fungicola spores is inhibited by the microflora, a phenomenon known as fungistasis. Fungistasis is annulled when the casing is colonized by A. bisporus hyphae. We demonstrated that addition of A. bisporus-associated sugars, similarly annulled the casing fungistasis. However, casing fungistasis does not seem to be based on competition for resources as L. fungicola spores germinate regardless of nutrient availability. Pseudomonas bacteria are a dominant group of bacteria in the casing and have previously been implied to be essential for the development of fungistasis in soils. Antibiotics produced by model strain Pseudomonas fluorescens CHA0 inhibited L. fungicola spore germination. Addition of glucose desensitized spores of L. fungicola, which resulted in germination in the presence of antibiotics. We conclude that antibiotics produced by the microflora most likely cause fungistasis.
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Affiliation(s)
- Roeland L Berendsen
- Plant-Microbe Interactions Molecular Microbiology, Department of Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands
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Xu XM, Jeffries P, Pautasso M, Jeger MJ. Combined use of biocontrol agents to manage plant diseases in theory and practice. PHYTOPATHOLOGY 2011; 101:1024-1031. [PMID: 21554184 DOI: 10.1094/phyto-08-10-0216] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Effective use of biological control agents (BCAs) is a potentially important component of sustainable agriculture. Recently, there has been an increasing interest among researchers in using combinations of BCAs to exploit potential synergistic effects among them. The methodology for investigating such synergistic effects was reviewed first and published results were then assessed for available evidence for synergy. Correct formulation of hypotheses based on the theoretical definition of independence (Bliss independence or Loewe additivity) and the subsequent and statistical testing for the independence-synergistic-antagonistic interactions have rarely been carried out thus far in studies on biocontrol of plant diseases. Thus, caution must be taken when interpreting reported "synergistic" effects without assessing the original publications. Recent theoretical modeling work suggested that disease suppression from combined use of two BCAs was, in general, very similar to that achieved by the more efficacious one, indicating no synergistic but more likely antagonistic interactions. Only in 2% of the total 465 published treatments was there evidence for synergistic effects among BCAs. In the majority of the cases, antagonistic interactions among BCAs were indicated. Thus, both theoretical and experimental studies suggest that, in combined use of BCAs, antagonistic interactions among BCAs are more likely to occur than synergistic interactions. Several research strategies, including formulation of synergy hypotheses in relation to biocontrol mechanisms, are outlined to exploit microbial mixtures for uses in biocontrol of plant diseases.
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Affiliation(s)
- X-M Xu
- College of Plant Protection, Northwest A & F University, Shaanxi, People's Republic of China.
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