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Cecala JM, Vannette RL. Nontarget impacts of neonicotinoids on nectar-inhabiting microbes. Environ Microbiol 2024; 26:e16603. [PMID: 38494634 DOI: 10.1111/1462-2920.16603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Accepted: 02/23/2024] [Indexed: 03/19/2024]
Abstract
Plant-systemic neonicotinoid (NN) insecticides can exert non-target impacts on organisms like beneficial insects and soil microbes. NNs can affect plant microbiomes, but we know little about their effects on microbial communities that mediate plant-insect interactions, including nectar-inhabiting microbes (NIMs). Here we employed two approaches to assess the impacts of NN exposure on several NIM taxa. First, we assayed the in vitro effects of six NN compounds on NIM growth using plate assays. Second, we inoculated a standardised NIM community into the nectar of NN-treated canola (Brassica napus) and assessed microbial survival and growth after 24 h. With few exceptions, in vitro NN exposure tended to decrease bacterial growth metrics. However, the magnitude of the decrease and the NN concentrations at which effects were observed varied substantially across bacteria. Yeasts showed no consistent in vitro response to NNs. In nectar, we saw no effects of NN treatment on NIM community metrics. Rather, NIM abundance and diversity responded to inherent plant qualities like nectar volume. In conclusion, we found no evidence that NIMs respond to field-relevant NN levels in nectar within 24 h, but our study suggests that context, specifically assay methods, time and plant traits, is important in assaying the effects of NNs on microbial communities.
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Affiliation(s)
- Jacob M Cecala
- Department of Entomology & Nematology, University of California, Davis, California, USA
| | - Rachel L Vannette
- Department of Entomology & Nematology, University of California, Davis, California, USA
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2
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Salam MTB, Kataoka R. Changes in the Endophytic Bacterial Community of Brassica rapa after Application of Systemic Insecticides. Int J Mol Sci 2023; 24:15306. [PMID: 37894986 PMCID: PMC10607537 DOI: 10.3390/ijms242015306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 10/16/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
Insecticides not only control target pests but also adversely affect non-target communities including humans, animals, and microbial communities in host plants and soils. The effect of insecticides on non-target communities, especially endophytic bacterial communities, remains poorly understood. Two phases of treatments were conducted to compare the trends in endophytic bacterial response after insecticide application. Endophytic bacteria were isolated at 2 and 4 weeks after germination. Most insecticide treatments showed a declining trend in bacterial diversity and abundance, whereas an increasing trend was observed in the control. Therefore, insecticide use negatively affected non-target endophytic bacterial communities. Bacillus spp. was mostly dominant in the early stage in both insecticide treatment and control groups. Nevertheless, in the matured stage, mostly bacteria including Pseudomonas spp., Priestia spp. were dominant in groups treated with high insecticide concentrations. Therefore, plants can regulate and moderate their microbiome during their lifecycle depending on surrounding environmental conditions.
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Affiliation(s)
- Md. Tareq Bin Salam
- Faculty of Life and Environmental Sciences, University of Yamanashi, Kofu 400-8510, Yamanashi, Japan;
- Soil, Water and Environment Discipline, Khulna University, Khulna 9208, Bangladesh
| | - Ryota Kataoka
- Faculty of Life and Environmental Sciences, University of Yamanashi, Kofu 400-8510, Yamanashi, Japan;
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3
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Fatemi S, Haelewaters D, Urbina H, Brown S, Houston ML, Aime MC. Sporobolomyces lactucae sp. nov. (Pucciniomycotina, Microbotryomycetes, Sporidiobolales): An Abundant Component of Romaine Lettuce Phylloplanes. J Fungi (Basel) 2022; 8:jof8030302. [PMID: 35330304 PMCID: PMC8951336 DOI: 10.3390/jof8030302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 02/28/2022] [Accepted: 03/07/2022] [Indexed: 11/24/2022] Open
Abstract
Shifts in food microbiomes may impact the establishment of human pathogens, such as virulent lineages of Escherichia coli, and thus are important to investigate. Foods that are often consumed raw, such as lettuce, are particularly susceptible to such outbreaks. We have previously found that an undescribed Sporobolomyces yeast is an abundant component of the mycobiome of commercial romaine lettuce (Lactuca sativa). Here, we formally describe this species as Sporobolomyces lactucae sp. nov. (Pucciniomycotina, Microbotryomycetes, and Sporidiobolales). We isolated multiple strains of this yeast from commercial romaine lettuce purchased from supermarkets in Illinois and Indiana; additional isolates were obtained from various plant phylloplanes in California. S. lactucae is a red-pigmented species that is similar in appearance to other members of the genus Sporobolomyces. However, it can be differentiated by its ability to assimilate glucuronate and D-glucosamine. Gene genealogical concordance supports S. lactucae as a new species. The phylogenetic reconstruction of a four-locus dataset, comprising the internal transcribed spacer and large ribosomal subunit D1/D2 domain of the ribosomal RNA gene, translation elongation factor 1-α, and cytochrome B, places S. lactucae as a sister to the S. roseus clade. Sporobolomyces lactucae is one of the most common fungi in the lettuce microbiome.
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Affiliation(s)
- Samira Fatemi
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA; (S.F.); (D.H.); (H.U.); (S.B.); (M.L.H.)
| | - Danny Haelewaters
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA; (S.F.); (D.H.); (H.U.); (S.B.); (M.L.H.)
- Research Group Mycology, Department of Biology, Ghent University, 9000 Ghent, Belgium
- Faculty of Science, University of South Bohemia, 370 05 České Budějovice, Czech Republic
| | - Hector Urbina
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA; (S.F.); (D.H.); (H.U.); (S.B.); (M.L.H.)
- Division of Plant Industry, Florida Department of Agriculture and Consumer Services, Gainesville, FL 32608, USA
| | - Samuel Brown
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA; (S.F.); (D.H.); (H.U.); (S.B.); (M.L.H.)
| | - Makenna L. Houston
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA; (S.F.); (D.H.); (H.U.); (S.B.); (M.L.H.)
| | - M. Catherine Aime
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA; (S.F.); (D.H.); (H.U.); (S.B.); (M.L.H.)
- Correspondence:
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4
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Chang Y, Xia X, Sui L, Kang Q, Lu Y, Li L, Liu W, Li Q, Zhang Z. Endophytic colonization of entomopathogenic fungi increases plant disease resistance by changing the endophytic bacterial community. J Basic Microbiol 2021; 61:1098-1112. [PMID: 34738230 DOI: 10.1002/jobm.202100494] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/11/2021] [Accepted: 10/22/2021] [Indexed: 11/07/2022]
Abstract
Various mechanisms are involved in plant disease resistance mediated by entomopathogenic fungi; however, the role of plant endophytic microbes in disease resistance is unknown. In the present study, we showed that the disease incidence of northern corn leaf blight caused by Exserohilum turcicum (Et) on maize was reduced significantly by soil inoculation with Beauveria bassiana (Bb). Meanwhile, B. bassiana colonization and E. turcicum infection increased the diversity and abundance and diversity of endophytic bacteria and fungi, respectively, while the abundance of endophytic bacterial of the Bb + Et treatment decreased significantly compared with that of Et treatment alone. However, Bb + Et treatment increased the relative abundance of plant beneficial bacteria significantly, for example, Burkholderia and Pseudomonas. Network analyses showed that the microbiome complexity increased after soil inoculation with B. bassiana. Taken together, these results revealed the potential mechanism by which entomopathogenic fungi exert biological control of maize leaf spot disease.
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Affiliation(s)
- Yuming Chang
- Jilin Key Laboratory of Agricultural Microbiology, Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Affairs, Jilin Academy of Agricultural Sciences, Changchun, China.,College of Life Sciences, Jilin Agricultural University, Changchun, China
| | - Xinyao Xia
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
| | - Li Sui
- Jilin Key Laboratory of Agricultural Microbiology, Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Affairs, Jilin Academy of Agricultural Sciences, Changchun, China
| | - Qin Kang
- Jilin Key Laboratory of Agricultural Microbiology, Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Affairs, Jilin Academy of Agricultural Sciences, Changchun, China.,Department of Entomology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Yang Lu
- Jilin Key Laboratory of Agricultural Microbiology, Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Affairs, Jilin Academy of Agricultural Sciences, Changchun, China
| | - Le Li
- Jilin Key Laboratory of Agricultural Microbiology, Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Affairs, Jilin Academy of Agricultural Sciences, Changchun, China.,College of Plant Protection, Jilin Agricultural University, Changchun, China
| | - Wende Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
| | - Qiyun Li
- Jilin Key Laboratory of Agricultural Microbiology, Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Affairs, Jilin Academy of Agricultural Sciences, Changchun, China
| | - Zhengkun Zhang
- Jilin Key Laboratory of Agricultural Microbiology, Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Affairs, Jilin Academy of Agricultural Sciences, Changchun, China
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Katsoula A, Vasileiadis S, Karamanoli K, Vokou D, Karpouzas DG. Factors Structuring the Epiphytic Archaeal and Fungal Communities in a Semi-arid Mediterranean Ecosystem. MICROBIAL ECOLOGY 2021; 82:638-651. [PMID: 33594547 DOI: 10.1007/s00248-021-01712-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 02/04/2021] [Indexed: 06/12/2023]
Abstract
The phyllosphere microbiome exerts a strong effect on plants' productivity, and its composition is determined by various factors. To date, most phyllosphere studies have focused on bacteria, while fungi and especially archaea have been overlooked. We studied the effects of plant host and season on the abundance and diversity of the epiphytic archaeal and fungal communities in a typical semi-arid Mediterranean ecosystem. We collected leaves in two largely contrasting seasons (summer and winter) from eight perennial species of varying attributes which could be grouped into the following: (i) high-canopy, evergreen sclerophyllοus shrubs with leathery leaves, and low-canopy, either semi-deciduous shrubs or non-woody perennials with non-leathery leaves, and (ii) aromatic and non-aromatic plants. We determined the abundance of epiphytic Crenarchaea, total fungi, Alternaria and Cladosporium (main airborne fungi) via q-PCR and the structure of the epiphytic archaeal and fungal communities via amplicon sequencing. We observed a strong seasonal effect with all microbial groups examined showing higher abundance in summer. Plant host and season were equally important determinants of the composition of the fungal community consisted mostly of Ascomycota, with Hypocreales dominating in winter and Capnodiales and Pleosporales in summer. In contrast, the archaeal community showed plant host driven patterns dominated by the Soil Crenarchaeotic Group (SCG) and Aenigmarchaeota. Plant habit and aromatic nature exhibited filtering effects only on the epiphytic fungal communities. Our study provides a first in-depth analysis of the key determinants shaping the phyllosphere archaeal and fungal communities of a semi-arid Mediterranean ecosystem.
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Affiliation(s)
- A Katsoula
- Department of Biochemistry and Biotechnology, Laboratory of Plant and Environmental Biotechnology, University of Thessaly, Viopolis, 41500, Larissa, Greece
| | - S Vasileiadis
- Department of Biochemistry and Biotechnology, Laboratory of Plant and Environmental Biotechnology, University of Thessaly, Viopolis, 41500, Larissa, Greece
| | - K Karamanoli
- School of Agriculture, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - D Vokou
- Department of Ecology, School of Biology, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece.
| | - D G Karpouzas
- Department of Biochemistry and Biotechnology, Laboratory of Plant and Environmental Biotechnology, University of Thessaly, Viopolis, 41500, Larissa, Greece.
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6
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Ma Y, Fort T, Marais A, Lefebvre M, Theil S, Vacher C, Candresse T. Leaf-associated fungal and viral communities of wild plant populations differ between cultivated and natural ecosystems. PLANT-ENVIRONMENT INTERACTIONS (HOBOKEN, N.J.) 2021; 2:87-99. [PMID: 37284285 PMCID: PMC10168098 DOI: 10.1002/pei3.10043] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 03/04/2021] [Accepted: 03/08/2021] [Indexed: 06/08/2023]
Abstract
Plants are colonized by diverse fungal and viral communities that influence their growth and survival as well as ecosystem functioning. Viruses interact with both plants and the fungi they host. Our understanding of plant-fungi-virus interactions is very limited, especially in wild plants. Combining metagenomic and culturomic approaches, we assessed the richness, diversity, and composition of leaf-associated fungal and viral communities from pools of herbaceous wild plants representative of four sites corresponding to cultivated or natural ecosystems. We identified 161 fungal families and 18 viral families comprising 249 RNA-dependent RNA polymerase-based operational taxonomic units (RdRp OTUs) from leaves. Fungal culturomics captured 12.3% of the fungal diversity recovered with metagenomic approaches and, unexpectedly, retrieved viral OTUs that were almost entirely different from those recovered by leaf metagenomics. Ecosystem management had a significant influence on both leaf mycobiome and virome, with a higher fungal community richness in natural ecosystems and a higher viral family richness in cultivated ecosystems, suggesting that leaf-associated fungal and viral communities are under the influence of different ecological drivers. Both the leaf-associated fungal and viral community compositions showed a strong site-specificity. Further research is needed to confirm these trends and unravel the factors structuring plant-fungi-virus interactions in wild plant populations.
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Affiliation(s)
- Yuxin Ma
- Univ. BordeauxINRAEUMR 1332 BFPVillenave d’Ornon cedexFrance
| | | | - Armelle Marais
- Univ. BordeauxINRAEUMR 1332 BFPVillenave d’Ornon cedexFrance
| | - Marie Lefebvre
- Univ. BordeauxINRAEUMR 1332 BFPVillenave d’Ornon cedexFrance
| | - Sébastien Theil
- Univ. BordeauxINRAEUMR 1332 BFPVillenave d’Ornon cedexFrance
- Present address:
INRA UMRF20, côte de ReyneAurillac15000France
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7
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Parizadeh M, Mimee B, Kembel SW. Neonicotinoid Seed Treatments Have Significant Non-target Effects on Phyllosphere and Soil Bacterial Communities. Front Microbiol 2021; 11:619827. [PMID: 33584586 PMCID: PMC7873852 DOI: 10.3389/fmicb.2020.619827] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 12/14/2020] [Indexed: 01/04/2023] Open
Abstract
The phyllosphere and soil are dynamic habitats for microbial communities. Non-pathogenic microbiota, including leaf and soil beneficial bacteria, plays a crucial role in plant growth and health, as well as in soil fertility and organic matter production. In sustainable agriculture, it is important to understand the composition of these bacterial communities, their changes in response to disturbances, and their resilience to agricultural practices. Widespread pesticide application may have had non-target impacts on these beneficial microorganisms. Neonicotinoids are a family of systemic insecticides being vastly used to control soil and foliar pests in recent decades. A few studies have demonstrated the long-term and non-target effects of neonicotinoids on agroecosystem microbiota, but the generality of these findings remains unclear. In this study, we used 16S rRNA gene amplicon sequencing to characterize the effects of neonicotinoid seed treatment on soil and phyllosphere bacterial community diversity, composition and temporal dynamics in a 3-year soybean/corn rotation in Quebec, Canada. We found that habitat, host species and time are stronger drivers of variation in bacterial composition than neonicotinoid application. They, respectively, explained 37.3, 3.2, and 2.9% of the community variation. However, neonicotinoids did have an impact on bacterial community structure, especially on the taxonomic composition of soil communities (2.6%) and over time (2.4%). They also caused a decrease in soil alpha diversity in the middle of the growing season. While the neonicotinoid treatment favored some bacterial genera known as neonicotinoid biodegraders, there was a decline in the relative abundance of some potentially beneficial soil bacteria in response to the pesticide application. Some of these bacteria, such as the plant growth-promoting rhizobacteria and the bacteria involved in the nitrogen cycle, are vital for plant growth and improve soil fertility. Overall, our results indicate that neonicotinoids have non-target effects on phyllosphere and soil bacterial communities in a soybean-corn agroecosystem. Exploring the interactions among bacteria and other organisms, as well as the bacterial functional responses to the pesticide treatment, may enhance our understanding of these non-target effects and help us adapt agricultural practices to control these impacts.
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Affiliation(s)
- Mona Parizadeh
- Agriculture and Agri-Food Canada, Saint-Jean-sur-Richelieu, Quebec, QC, Canada
- Département des sciences biologiques, Université du Québec à Montréal, Montréal, QC, Canada
| | - Benjamin Mimee
- Agriculture and Agri-Food Canada, Saint-Jean-sur-Richelieu, Quebec, QC, Canada
| | - Steven W. Kembel
- Département des sciences biologiques, Université du Québec à Montréal, Montréal, QC, Canada
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Katsoula A, Vasileiadis S, Sapountzi M, Karpouzas DG. The response of soil and phyllosphere microbial communities to repeated application of the fungicide iprodione: accelerated biodegradation or toxicity? FEMS Microbiol Ecol 2020; 96:5813261. [PMID: 32221586 DOI: 10.1093/femsec/fiaa056] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 03/23/2020] [Indexed: 12/30/2022] Open
Abstract
Pesticides interact with microorganisms in various ways with the outcome being negative or positive for the soil microbiota. Pesticides' effects on soil microorganisms have been studied extensively in soil but not in other pesticides-exposed microbial habitats like the phyllosphere. We tested the hypothesis that soil and phyllosphere support distinct microbial communities, but exhibit a similar response (accelerated biodegradation or toxicity) to repeated exposure to the fungicide iprodione. Pepper plants received four repeated foliage or soil applications of iprodione, which accelerated its degradation in soil (DT50_1st = 1.23 and DT50_4th = 0.48 days) and on plant leaves (DT50_1st > 365 and DT50_4th = 5.95 days). The composition of the epiphytic and soil bacterial and fungal communities, determined by amplicon sequencing, was significantly altered by iprodione. The archaeal epiphytic and soil communities responded differently; the former showed no response to iprodione. Three iprodione-degrading Paenarthrobacter strains were isolated from soil and phyllosphere. They hydrolyzed iprodione to 3,5-dichloraniline via the formation of 3,5-dichlorophenyl-carboxiamide and 3,5-dichlorophenylurea-acetate, a pathway shared by other soil-derived arthrobacters implying a phylogenetic specialization in iprodione biotransformation. Our results suggest that iprodione-repeated application could affect soil and epiphytic microbial communities with implications for the homeostasis of the plant-soil system and agricultural production.
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Affiliation(s)
- A Katsoula
- Laboratory of Plant and Environmental Biotechnology, Department of Biochemistry and Biotechnology, University of Thessaly, Viopolis 41500, Larissa, Greece
| | - S Vasileiadis
- Laboratory of Plant and Environmental Biotechnology, Department of Biochemistry and Biotechnology, University of Thessaly, Viopolis 41500, Larissa, Greece
| | - M Sapountzi
- Laboratory of Plant and Environmental Biotechnology, Department of Biochemistry and Biotechnology, University of Thessaly, Viopolis 41500, Larissa, Greece
| | - Dimitrios G Karpouzas
- Laboratory of Plant and Environmental Biotechnology, Department of Biochemistry and Biotechnology, University of Thessaly, Viopolis 41500, Larissa, Greece
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9
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Wemheuer F, Berkelmann D, Wemheuer B, Daniel R, Vidal S, Bisseleua Daghela HB. Agroforestry Management Systems Drive the Composition, Diversity, and Function of Fungal and Bacterial Endophyte Communities in Theobroma Cacao Leaves. Microorganisms 2020; 8:E405. [PMID: 32183118 PMCID: PMC7143032 DOI: 10.3390/microorganisms8030405] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 03/04/2020] [Accepted: 03/11/2020] [Indexed: 12/22/2022] Open
Abstract
Cacao (Theobroma cacao L.) is one of the most economically important crops worldwide. Despite the important role of endophytes for plant growth and health, very little is known about the effect of agroforestry management systems on the endophyte communities of T. cacao. To close this knowledge gap, we investigated the diversity, community composition, and function of bacterial and fungal endophytes in the leaves of T. cacao trees growing in five major cacao-growing regions in the central region of Cameroon using DNA metabarcoding. Fungal but not bacterial alpha diversity measures differed significantly between the agroforestry management systems. Interestingly, less managed home-garden cacao forests harbored the lowest fungal richness and diversity. Our results suggest that the composition of bacterial and fungal endophyte communities is predominantly affected by agroforestry management systems and, to a lesser extent, by environmental properties. The core microbiome detected comprised important fungal phytopathogens, such as Lasiodiplodia species. Several predicted pathways of bacterial endophytes and functional guilds of fungal endophytes differed between the agroforest systems which might be attributed to bacteria and fungi specifically associated with a single agroforest. Our results provide the basis for future studies on foliar fungal and bacterial endophytes of T. cacao and their responsiveness towards agroforestry management systems.
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Affiliation(s)
- Franziska Wemheuer
- Section of Agricultural Entomology, Department of Crop Sciences, University of Göttingen, Grisebachstr. 6, D-37077 Göttingen, Germany; (F.W.); (H.B.B.D.)
| | - Dirk Berkelmann
- Genomic and Applied Microbiology & Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, University of Göttingen, Grisebachstr. 8, D-37077 Göttingen, Germany; (D.B.); (B.W.); (R.D.)
| | - Bernd Wemheuer
- Genomic and Applied Microbiology & Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, University of Göttingen, Grisebachstr. 8, D-37077 Göttingen, Germany; (D.B.); (B.W.); (R.D.)
| | - Rolf Daniel
- Genomic and Applied Microbiology & Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, University of Göttingen, Grisebachstr. 8, D-37077 Göttingen, Germany; (D.B.); (B.W.); (R.D.)
| | - Stefan Vidal
- Section of Agricultural Entomology, Department of Crop Sciences, University of Göttingen, Grisebachstr. 6, D-37077 Göttingen, Germany; (F.W.); (H.B.B.D.)
| | - Hervé Bertin Bisseleua Daghela
- Section of Agricultural Entomology, Department of Crop Sciences, University of Göttingen, Grisebachstr. 6, D-37077 Göttingen, Germany; (F.W.); (H.B.B.D.)
- Laboratory of Entomology, Institute of Agricultural Research for Development (IRAD), BP 2067, Yaoundé, Cameroon
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10
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Nerva L, Pagliarani C, Pugliese M, Monchiero M, Gonthier S, Gullino ML, Gambino G, Chitarra W. Grapevine Phyllosphere Community Analysis in Response to Elicitor Application against Powdery Mildew. Microorganisms 2019; 7:microorganisms7120662. [PMID: 31817902 PMCID: PMC6956034 DOI: 10.3390/microorganisms7120662] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 11/26/2019] [Accepted: 12/05/2019] [Indexed: 12/23/2022] Open
Abstract
The reduction of antimicrobial treatments and mainly the application of environmentally friendly compounds, such as resistance elicitors, is an impelling challenge to undertake more sustainable agriculture. We performed this research to study the effectiveness of non-conventional compounds in reducing leaf fungal attack and to investigate whether they influence the grape phyllosphere. Pathogenicity tests were conducted on potted Vitis vinifera "Nebbiolo" and "Moscato" cultivars infected with the powdery mildew agent (Erysiphe necator) and treated with three elicitors. Differences in the foliar microbial community were then evaluated by community-level physiological profiling by using BiologTM EcoPlates, high throughput sequencing of the Internal Transcribed Spacer (ITS) region, and RNA sequencing for the viral community. In both cultivars, all products were effective as they significantly reduced pathogen development. EcoPlate analysis and ITS sequencing showed that the microbial communities were not influenced by the alternative compound application, confirming their specific activity as plant defense elicitors. Nevertheless, "Moscato" plants were less susceptible to the disease and presented different phyllosphere composition, resulting in a richer viral community, when compared with the "Nebbiolo" plants. The observed effect on microbial communities pointed to the existence of distinct genotype-specific defense mechanisms independently of the elicitor application.
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Affiliation(s)
- Luca Nerva
- Research Centre for Viticulture and Enology, Council for Agricultural Research and Economics (CREA-VE), Via XXVIII Aprile 26, 31015 Conegliano, Italy
- Institute for Sustainable Plant Protection, National Research Council (IPSP-CNR), Strada delle Cacce 73, 10135 Torino, Italy; (C.P.); (S.G.); (G.G.)
- Correspondence: (L.N.); (W.C.); Tel.: +39-04-3845-6712 (W.C.); Fax: +39-04-3845-0773 (W.C.)
| | - Chiara Pagliarani
- Institute for Sustainable Plant Protection, National Research Council (IPSP-CNR), Strada delle Cacce 73, 10135 Torino, Italy; (C.P.); (S.G.); (G.G.)
| | - Massimo Pugliese
- Centre of Competence for the Innovation in the Agro-Environmental Sector (AGROINNOVA), University of Torino, Largo Paolo Braccini 2, 10095 Grugliasco (TO), Italy; (M.P.); (M.L.G.)
- Department of Agricultural, Forest and Food Sciences (DISAFA), University of Torino, Largo Paolo Braccini 2, 10095 Grugliasco (TO), Italy
| | | | - Solène Gonthier
- Institute for Sustainable Plant Protection, National Research Council (IPSP-CNR), Strada delle Cacce 73, 10135 Torino, Italy; (C.P.); (S.G.); (G.G.)
- Biocomputing and Modelling Department, National Institute of Applied Sciences, INSA Lyon, 69621 Villeurbanne cedex, France
| | - Maria Lodovica Gullino
- Centre of Competence for the Innovation in the Agro-Environmental Sector (AGROINNOVA), University of Torino, Largo Paolo Braccini 2, 10095 Grugliasco (TO), Italy; (M.P.); (M.L.G.)
- Department of Agricultural, Forest and Food Sciences (DISAFA), University of Torino, Largo Paolo Braccini 2, 10095 Grugliasco (TO), Italy
| | - Giorgio Gambino
- Institute for Sustainable Plant Protection, National Research Council (IPSP-CNR), Strada delle Cacce 73, 10135 Torino, Italy; (C.P.); (S.G.); (G.G.)
| | - Walter Chitarra
- Research Centre for Viticulture and Enology, Council for Agricultural Research and Economics (CREA-VE), Via XXVIII Aprile 26, 31015 Conegliano, Italy
- Institute for Sustainable Plant Protection, National Research Council (IPSP-CNR), Strada delle Cacce 73, 10135 Torino, Italy; (C.P.); (S.G.); (G.G.)
- Correspondence: (L.N.); (W.C.); Tel.: +39-04-3845-6712 (W.C.); Fax: +39-04-3845-0773 (W.C.)
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11
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Shi S, Tian L, Xu S, Ji L, Nasir F, Li X, Song Z, Tian C. The rhizomicrobiomes of wild and cultivated crops react differently to fungicides. Arch Microbiol 2019; 201:477-486. [PMID: 30361816 DOI: 10.1007/s00203-018-1586-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 06/13/2018] [Accepted: 10/17/2018] [Indexed: 12/18/2022]
Abstract
The fungicides used to control diseases in cereal production can have adverse effects on non-target microbial communities, with possible consequences for plant health and productivity. Although we know that fungicides affect microbial community structure and soil activities, it is unclear how crop cultivars have altered the impact of fungicides on rhizomicrobiomes. In this study, the rhizosphere bacterial and fungal communities and structures of cultivated crops and their wild relatives were studied by Illumina MiSeq sequencing analysis. The results indicated that the rhizomicrobiome communities of wild crops reacted more strongly to fungicides than that of their cultivated relatives. Furthermore, fungal community composition was more affected by fungicides than bacterial community composition. Remarkably, the same trend was observed in both soybean and rice with regard to the influence of crop cultivar on the response of the rhizomicrobiome to fungicide application, although the level of the response was not similar. We report for the first time that the rhizomicrobiomes of wild crops reacted more strongly to fungicides than the rhizomicrobiomes of cultivated crops.
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Affiliation(s)
- Shaohua Shi
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, Jilin, China
| | - Lei Tian
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, Jilin, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Shangqi Xu
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, Jilin, China
| | - Li Ji
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, Jilin, China
| | - Fahad Nasir
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, Jilin, China
| | - Xiujun Li
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, Jilin, China
| | - Zhiping Song
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Institute of Biodiversity Science, Fudan University, Shanghai, 200433, China
| | - Chunjie Tian
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, Jilin, China.
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12
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Screening of Rice Endophytic Biofertilizers with Fungicide Tolerance and Plant Growth-Promoting Characteristics. SUSTAINABILITY 2019. [DOI: 10.3390/su11041133] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The application of pesticides is unavoidable in conventional agricultural practice. To develop effective biofertilizers, bacterial strains with both pesticide tolerance and plant growth-promoting (PGP) traits were isolated for further testing. Seedlings of rice (Oryza sativa) were planted in soil with 1, 5, or 10 times the recommended rates of the fungicides etridiazole, metalaxyl, and tricyclazole. Endophytic bacteria were isolated from roots of rice seedlings. The bacterial 16S rDNA sequences and related PGP characteristics including potential nitrogen fixation, phosphorus-solubilizing and indole acetic acid (IAA) production ability were further examined. In all, 17 different strains were obtained from rice seedling roots; five strains with both nitrogen fixation potential and IAA production ability included Rhizobium larrymoorei E2, Bacillus aryabhattai E7, Bacillus aryabhattai MN1, Pseudomonas granadensis T6, and Bacillus fortis T9. Except for T9, all strains could tolerate two or more fungicides. We inoculated rice roots with the endophytic bacteria and all conferred rice growth-promoting ability. Bacillus aryabhattai MN1 was further tested and showed high tryptophan dose-dependent IAA production ability, tolerance towards etridiazole and metalaxyl application and should be considered a potential bacterial biofertilizer.
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13
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Thapa S, Prasanna R, Ranjan K, Velmourougane K, Ramakrishnan B. Nutrients and host attributes modulate the abundance and functional traits of phyllosphere microbiome in rice. Microbiol Res 2017; 204:55-64. [PMID: 28870292 DOI: 10.1016/j.micres.2017.07.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 07/11/2017] [Accepted: 07/15/2017] [Indexed: 02/04/2023]
Abstract
The abundance of phyllosphere bacterial communities of seven genotypes of rice ADT- 38, ADT-43, CR-1009, PB-1, PS-5, P-44, and PB-1509 was investigated, in relation to nutrient dynamics of rhizosphere and leaves. P-44 genotype recorded highest pigment accumulation, while genotypes CR-1009 and P-44 exhibited most number of different bacterial morphotypes, Colony forming units in two media (Nutrient agar and R2A) varied significantly and ranged from 106-107 per g plant tissues. Among the selected 60 distinct morphotypes, IAA and siderophore producers were the dominant functional types. Biocontrol activity against Drechslera oryzae was shown by 38 isolates, while 17 and 9 isolates were potent against Rhizoctonia solani and Magnaporthe oryzae respectively. Principal Component Analysis (PCA) illustrated the significant effects of selected soil and leaf nutrients of seven rice varieties on the culturable phyllospheric population (log CFU), particularly in the R2A medium. Eigen values revealed that 83% of the variance observed could be assigned to Leaf-Fe, Leaf-Mn, chlorophyll b and soil organic carbon (OC). Quantitative PCR analyses of abundance of bacteria, cyanobacteria and archaebacteria revealed a host-specific response, with CR-1009 showing highest number of 16S rRNA copies of bacterial members, while both P-44 and PS-5 had higher cyanobacterial abundance, but lowest number of those belonging to archaebacteria. Nutritional aspects of leaf and soil influenced the abundance of bacteria and their functional attributes; this is of interest for enhancing the efficacy of foliar inoculants, thereby, improving plant growth and disease tolerance.
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Affiliation(s)
- Shobit Thapa
- Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | - Radha Prasanna
- Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India.
| | - Kunal Ranjan
- Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
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14
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Hong M, Peng G, Keyhani NO, Xia Y. Application of the entomogenous fungus, Metarhizium anisopliae, for leafroller (Cnaphalocrocis medinalis) control and its effect on rice phyllosphere microbial diversity. Appl Microbiol Biotechnol 2017; 101:6793-6807. [PMID: 28695229 DOI: 10.1007/s00253-017-8390-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 06/12/2017] [Accepted: 06/13/2017] [Indexed: 01/22/2023]
Abstract
Microbial pesticides form critical components of integrated pest management (IPM) practices. Little, however, is known regarding the impacts of these organisms on the indigenous microbial community. We show that Metarhizium anisopliae strain CQMa421 was highly effective in controlling the rice leafroller, Cnaphalocrocis medinalis Guenee. In addition, M. anisopliae distribution and its effects on phyllosphere microbial diversity after application in field trials were investigated. Phylloplane specific distribution of the fungus was observed over time, with more rapid declines of M. anisopliae CFUs (colony-forming units) seen in the top leaf layer as compared to lower layers. Application of the fungus resulted in transient changes in the endogenous microbial diversity with variations seen in the bacterial observed species and Shannon index. Notable increases in both parameters were seen at 6-day post-application of M. anisopliae, although significant variation within sample replicates for bacteria and fungi were noted. Application of M. anisopliae increased the relative distribution of bacterial species implicated in plant growth promotion and organic pollutant degradation, e.g., Methylobacterium, Sphingobium, and Deinococcus. These data show minimal impact of M. anisopliae on endogenous microbial diversity with transient changes in bacterial abundance/diversity that may result in added benefits to crops.
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Affiliation(s)
- Mingsheng Hong
- Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing, 400045, People's Republic of China.,Chongqing Engineering Research Center for Fungal Insecticide, Chongqing, 400045, People's Republic of China.,Key Laboratory of Gene Function and Regulation Technologies under Chongqing Municipal Education Commission, Chongqing, 400045, People's Republic of China
| | - Guoxiong Peng
- Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing, 400045, People's Republic of China.,Chongqing Engineering Research Center for Fungal Insecticide, Chongqing, 400045, People's Republic of China.,Key Laboratory of Gene Function and Regulation Technologies under Chongqing Municipal Education Commission, Chongqing, 400045, People's Republic of China
| | - Nemat O Keyhani
- Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing, 400045, People's Republic of China.,Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, 32611, USA
| | - Yuxian Xia
- Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing, 400045, People's Republic of China. .,Chongqing Engineering Research Center for Fungal Insecticide, Chongqing, 400045, People's Republic of China. .,Key Laboratory of Gene Function and Regulation Technologies under Chongqing Municipal Education Commission, Chongqing, 400045, People's Republic of China.
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15
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Walvekar VA, Bajaj S, Singh DK, Sharma S. Ecotoxicological assessment of pesticides and their combination on rhizospheric microbial community structure and function of Vigna radiata. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:17175-17186. [PMID: 28585016 DOI: 10.1007/s11356-017-9284-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 05/17/2017] [Indexed: 06/07/2023]
Abstract
India is one of the leading countries in production and indiscriminate consumption of pesticides. Owing to their xenobiotic nature, pesticides affect soil microorganisms that serve as mediators in plant growth promotion. Our study aimed to deliver a comprehensive picture, by comparing the effects of synthetic pesticides (chlorpyriphos, cypermethrin, and a combination of both) with a biopesticide (azadirachtin) at their recommended field application level (L), and three times the recommended dosage (H) on structure and function of microbial community in rhizosphere of Vigna radiata. Effect on culturable fraction was assessed by enumeration on selective media, while PCR-denaturing gradient gel electrophoresis (DGGE) was employed to capture total bacterial community diversity. This was followed by a metabolic sketch using community-level physiological profiling (CLPP), to obtain a broader picture of the non-target effects on rhizospheric microbial community. Although plant parameters were not significantly affected by pesticide application, the microbial community structure experienced an undesirable impact as compared to control devoid of pesticide treatment. Examination of DGGE banding patterns through cluster analysis revealed that microbial community structure of pesticide-treated soils had only 70% resemblance to control rhizospheric soil even at 45 days post application. Drastic changes in the metabolic profiles of pesticide-treated soils were also detected in terms of substrate utilization, rhizospheric diversity, and evenness. It is noteworthy that the effects exacerbated by biopesticide were comparable to that of synthetic pesticides, thus emphasizing the significance of ecotoxicological assessments before tagging biopesticides as "safe alternatives."
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Affiliation(s)
- Varsha Ashok Walvekar
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India
| | - Swati Bajaj
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Dileep K Singh
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Shilpi Sharma
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India.
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16
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Fort T, Robin C, Capdevielle X, Delière L, Vacher C. Foliar fungal communities strongly differ between habitat patches in a landscape mosaic. PeerJ 2016; 4:e2656. [PMID: 27833817 PMCID: PMC5101609 DOI: 10.7717/peerj.2656] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 10/05/2016] [Indexed: 11/28/2022] Open
Abstract
Background Dispersal events between habitat patches in a landscape mosaic can structure ecological communities and influence the functioning of agrosystems. Here we investigated whether short-distance dispersal events between vineyard and forest patches shape foliar fungal communities. We hypothesized that these communities homogenize between habitats over the course of the growing season, particularly along habitat edges, because of aerial dispersal of spores. Methods We monitored the richness and composition of foliar and airborne fungal communities over the season, along transects perpendicular to edges between vineyard and forest patches, using Illumina sequencing of the Internal Transcribed Spacer 2 (ITS2) region. Results In contrast to our expectation, foliar fungal communities in vineyards and forest patches increasingly differentiate over the growing season, even along habitat edges. Moreover, the richness of foliar fungal communities in grapevine drastically decreased over the growing season, in contrast to that of forest trees. The composition of airborne communities did not differ between habitats. The composition of oak foliar fungal communities change between forest edge and centre. Discussion These results suggest that dispersal events between habitat patches are not major drivers of foliar fungal communities at the landscape scale. Selective pressures exerted in each habitat by the host plant, the microclimate and the agricultural practices play a greater role, and might account for the differentiation of foliar fugal communities between habitats.
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Affiliation(s)
- Thomas Fort
- BIOGECO, UMR 1202, INRA, Université de Bordeaux , Cestas , France
| | - Cécile Robin
- BIOGECO, UMR 1202, INRA, Université de Bordeaux , Cestas , France
| | | | - Laurent Delière
- SAVE, UMR 1065, INRA, ISVV, Université de Bordeaux , Villenave d'Ornon , France
| | - Corinne Vacher
- BIOGECO, UMR 1202, INRA, Université de Bordeaux , Pessac , France
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17
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Vacher C, Hampe A, Porté AJ, Sauer U, Compant S, Morris CE. The Phyllosphere: Microbial Jungle at the Plant–Climate Interface. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2016. [DOI: 10.1146/annurev-ecolsys-121415-032238] [Citation(s) in RCA: 229] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Arndt Hampe
- BIOGECO, INRA, Univ. Bordeaux, 33610 Cestas, France
| | | | - Ursula Sauer
- Bioresources Unit, Department of Health and Environment, AIT Austrian Institute of Technology GmbH, 3430 Tulln, Austria
| | - Stéphane Compant
- Bioresources Unit, Department of Health and Environment, AIT Austrian Institute of Technology GmbH, 3430 Tulln, Austria
| | - Cindy E. Morris
- INRA, Unité de Recherche de Pathologie Végétale, 84143 Montfavet, France
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18
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Using a Control to Better Understand Phyllosphere Microbiota. PLoS One 2016; 11:e0163482. [PMID: 27669159 PMCID: PMC5036865 DOI: 10.1371/journal.pone.0163482] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 09/10/2016] [Indexed: 11/26/2022] Open
Abstract
An important data gap in our understanding of the phyllosphere surrounds the origin of the many microbes described as phyllosphere communities. Most sampling in phyllosphere research has focused on the collection of microbiota without the use of a control, so the opportunity to determine which taxa are actually driven by the biology and physiology of plants as opposed to introduced by environmental forces has yet to be fully realized. To address this data gap, we used plastic plants as inanimate controls adjacent to live tomato plants (phyllosphere) in the field with the hope of distinguishing between bacterial microbiota that may be endemic to plants as opposed to introduced by environmental forces. Using 16S rRNA gene amplicons to study bacterial membership at four time points, we found that the vast majority of all species-level operational taxonomic units were shared at all time-points. Very few taxa were unique to phyllosphere samples. A higher taxonomic diversity was consistently observed in the control samples. The high level of shared taxonomy suggests that environmental forces likely play a very important role in the introduction of microbes to plant surfaces. The observation that very few taxa were unique to the plants compared to the number that were unique to controls was surprising and further suggests that a subset of environmentally introduced taxa thrive on plants. This finding has important implications for improving our approach to the description of core phytobiomes as well as potentially helping us better understand how foodborne pathogens may become associated with plant surfaces.
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19
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Airborne and Grain Dust Fungal Community Compositions Are Shaped Regionally by Plant Genotypes and Farming Practices. Appl Environ Microbiol 2016; 82:2121-2131. [PMID: 26826229 DOI: 10.1128/aem.03336-15] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 01/22/2016] [Indexed: 12/26/2022] Open
Abstract
Chronic exposure to airborne fungi has been associated with different respiratory symptoms and pathologies in occupational populations, such as grain workers. However, the homogeneity in the fungal species composition of these bioaerosols on a large geographical scale and the different drivers that shape these fungal communities remain unclear. In this study, the diversity of fungi in grain dust and in the aerosols released during harvesting was determined across 96 sites at a geographical scale of 560 km(2) along an elevation gradient of 500 m by tag-encoded 454 pyrosequencing of the internal transcribed spacer (ITS) sequences. Associations between the structure of fungal communities in the grain dust and different abiotic (farming system, soil characteristics, and geographic and climatic parameters) and biotic (wheat cultivar and previous crop culture) factors were explored. These analyses revealed a strong relationship between the airborne and grain dust fungal communities and showed the presence of allergenic and mycotoxigenic species in most samples, which highlights the potential contribution of these fungal species to work-related respiratory symptoms of grain workers. The farming system was the major driver of the alpha and beta phylogenetic diversity values of fungal communities. In addition, elevation and soil CaCO3 concentrations shaped the alpha diversity, whereas wheat cultivar, cropping history, and the number of freezing days per year shaped the taxonomic beta diversity of these communities.
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20
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Resilience of the natural phyllosphere microbiota of the grapevine to chemical and biological pesticides. Appl Environ Microbiol 2015; 80:3585-96. [PMID: 24682305 DOI: 10.1128/aem.00415-14] [Citation(s) in RCA: 110] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The phyllosphere is colonized by complex microbial communities, which are adapted to the harsh habitat. Although the role and ecology of nonpathogenic microorganisms of the phyllosphere are only partially understood, leaf microbiota could have a beneficial role in plant growth and health. Pesticides and biocontrol agents are frequently applied to grapevines, but the impact on nontarget microorganisms of the phyllosphere has been marginally considered. In this study, we investigated the effect of a chemical fungicide (penconazole) and a biological control agent (Lysobacter capsici AZ78) on the leaf microbiota of the grapevine at three locations. Amplicons of the 16S rRNA gene and of the internal transcribed spacer were sequenced for bacterial and fungal identification, respectively. Pyrosequencing analysis revealed that the richness and diversity of bacterial and fungal populations were only minimally affected by the chemical and biological treatments tested, and they mainly differed according to grapevine locations. Indigenous microbial communities of the phyllosphere are adapted to environmental and biotic factors in the areas where the grapevines are grown, and they are resilient to the treatments tested. The biocontrol properties of phyllosphere communities against downy mildew differed among grapevine locations and were not affected by treatments, suggesting that biocontrol communities could be improved with agronomic practices to enrich beneficial populations in vineyards.
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21
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Fungicide effects on fungal community composition in the wheat phyllosphere. PLoS One 2014; 9:e111786. [PMID: 25369054 PMCID: PMC4219778 DOI: 10.1371/journal.pone.0111786] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 10/05/2014] [Indexed: 12/01/2022] Open
Abstract
The fungicides used to control diseases in cereal production can have adverse effects on non-target fungi, with possible consequences for plant health and productivity. This study examined fungicide effects on fungal communities on winter wheat leaves in two areas of Sweden. High-throughput 454 sequencing of the fungal ITS2 region yielded 235 operational taxonomic units (OTUs) at the species level from the 18 fields studied. It was found that commonly used fungicides had moderate but significant effect on fungal community composition in the wheat phyllosphere. The relative abundance of several saprotrophs was altered by fungicide use, while the effect on common wheat pathogens was mixed. The fungal community on wheat leaves consisted mainly of basidiomycete yeasts, saprotrophic ascomycetes and plant pathogens. A core set of six fungal OTUs representing saprotrophic species was identified. These were present across all fields, although overall the difference in OTU richness was large between the two areas studied.
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22
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Perazzolli M, Antonielli L, Storari M, Puopolo G, Pancher M, Giovannini O, Pindo M, Pertot I. Resilience of the natural phyllosphere microbiota of the grapevine to chemical and biological pesticides. Appl Environ Microbiol 2014. [PMID: 24682305 DOI: 10.1128/aem.00415-00411] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023] Open
Abstract
The phyllosphere is colonized by complex microbial communities, which are adapted to the harsh habitat. Although the role and ecology of nonpathogenic microorganisms of the phyllosphere are only partially understood, leaf microbiota could have a beneficial role in plant growth and health. Pesticides and biocontrol agents are frequently applied to grapevines, but the impact on nontarget microorganisms of the phyllosphere has been marginally considered. In this study, we investigated the effect of a chemical fungicide (penconazole) and a biological control agent (Lysobacter capsici AZ78) on the leaf microbiota of the grapevine at three locations. Amplicons of the 16S rRNA gene and of the internal transcribed spacer were sequenced for bacterial and fungal identification, respectively. Pyrosequencing analysis revealed that the richness and diversity of bacterial and fungal populations were only minimally affected by the chemical and biological treatments tested, and they mainly differed according to grapevine locations. Indigenous microbial communities of the phyllosphere are adapted to environmental and biotic factors in the areas where the grapevines are grown, and they are resilient to the treatments tested. The biocontrol properties of phyllosphere communities against downy mildew differed among grapevine locations and were not affected by treatments, suggesting that biocontrol communities could be improved with agronomic practices to enrich beneficial populations in vineyards.
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23
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Jacobsen CS, Hjelmsø MH. Agricultural soils, pesticides and microbial diversity. Curr Opin Biotechnol 2014; 27:15-20. [DOI: 10.1016/j.copbio.2013.09.003] [Citation(s) in RCA: 168] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 09/05/2013] [Accepted: 09/09/2013] [Indexed: 11/28/2022]
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