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Yang Z, Deng Y, Zhong L, Xiao R, Su X. Responses of soil bacterial and fungal denitrification and associated N 2O emissions to organochloride pesticide. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:167321. [PMID: 37748606 DOI: 10.1016/j.scitotenv.2023.167321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 09/16/2023] [Accepted: 09/22/2023] [Indexed: 09/27/2023]
Abstract
The extensive application of organochloride pesticides in agriculture has raised concerns about their potential negative impacts on soil microbial denitrification and associated N2O emissions. However, most studies have primarily focused on bacteria, and the contribution of fungi to N2O emissions and their response to organochloride pesticides have often been overlooked. In this study, 15N tracing combined with the respiration inhibition method was applied to examine the impacts of chlorothalonil on both fungal and bacterial denitrification. The results demonstrated that fungal N2O emissions dominated in the absence of chlorothalonil, accounting for 73 % of total N2O emissions. Chlorothalonil inhibited fungal and bacterial denitrification via different mechanisms and altered the main pathways of soil N2O emissions. Amplicon sequencing analyses indicated that chlorothalonil significantly reduced the abundances of N2O-producing fungi owing to its fungicidal effect and fungal N2O emissions significantly dropped. Molecular biological analyses revealed that chlorothalonil induced lower electron generation, transport, and consumption efficiencies, which led to the inhibition of denitrifying enzymes in bacteria. Bacterial N2O emissions dramatically increased and became the dominant source. These findings provide insights into the mechanisms by which N2O emissions from fungal and bacterial denitrification are influenced by chlorothalonil.
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Affiliation(s)
- Zhi Yang
- College of Eco-Environmental Engineering, Guizhou Minzu University, Guiyang 550025, China
| | - Yue Deng
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Lei Zhong
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Ran Xiao
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Xiaoxuan Su
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400715, China.
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Báez ME, Sarkar B, Peña A, Vidal J, Espinoza J, Fuentes E. Effect of surfactants on the sorption-desorption, degradation, and transport of chlorothalonil and hydroxy-chlorothalonil in agricultural soils. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 327:121545. [PMID: 37004862 DOI: 10.1016/j.envpol.2023.121545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 03/30/2023] [Accepted: 03/31/2023] [Indexed: 06/19/2023]
Abstract
The fungicide chlorothalonil (CTL) and its metabolite hydroxy chlorothalonil (OH-CTL) constitute a risk of soil and water contamination, highlighting the need to find suitable soil remediation methods for these compounds. Surfactants can promote the bioavailability of organic compounds for enhanced microbial degradation, but the performance depends on soil and surfactant properties, sorption-desorption equilibria of contaminants and surfactants, and possible adverse effects of surfactants on microorganisms. This study investigated the influence of five surfactants [e.g., Triton X-100 (TX-100), sodium dodecyl sulphate (SDS), hexadecyltrimethylammonium bromide (HDTMA), Aerosol 22 and Tween 80] on the sorption-desorption, degradation, and mobility of CTL and OH-CTL in two volcanic and one non-volcanic soil. Sorption and desorption of fungicides depended on the sorption of surfactants on soils, surfactants' capacity to neutralize the net negative charge of soils, surfactants' critical micellar concentration, and pH of soils. HDTMA was strongly adsorbed on soils, which shifted the fungicide sorption equilibria by increasing the distribution coefficient (Kd) values. Contrarily, SDS and TX-100 lowered CTL and OH-CTL sorption on soils by decreasing the Kd values, which resulted in an efficient extraction of the fungicide compounds from soil. SDS increased the degradation of CTL, especially in the non-volcanic soil (DT50 values were 14 and 7 days in natural and amended soils, with final residues <7% of the initial dose), whereas TX-100 enabled an early start and sustenance of OH-CTL degradation in all soils. CTL and OH-CTL stimulated soil microbial activities without noticeable deleterious effects of the surfactants. SDS and TX-100 also reduced the vertical transport of OH-CTL in soils. Results of this study could be extended to soils in other regions of the world because the tested soils represent widely different physical, chemical, and biological properties.
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Affiliation(s)
- María E Báez
- Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Olivos 1007, 8380000, Santiago, Chile.
| | - Binoy Sarkar
- Future Industries Institute, University of South Australia, Mawson Lakes, SA 5095, Australia
| | - Aránzazu Peña
- Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Avenida de las Palmeras 4, 18100 Armilla, Granada, Spain
| | - Jorge Vidal
- Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Olivos 1007, 8380000, Santiago, Chile
| | - Jeannette Espinoza
- Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Olivos 1007, 8380000, Santiago, Chile
| | - Edwar Fuentes
- Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Olivos 1007, 8380000, Santiago, Chile
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Xiao Z, Hou K, Zhou T, Zhang J, Li B, Du Z, Sun S, Zhu L. Effects of the fungicide trifloxystrobin on the structure and function of soil bacterial community. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2023; 99:104104. [PMID: 36893889 DOI: 10.1016/j.etap.2023.104104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 03/02/2023] [Accepted: 03/06/2023] [Indexed: 06/18/2023]
Abstract
Trifloxystrobin has been widely applied to prevent fungal diseases because of its high efficiency and desirable safety characteristics. In the present study, the effects of trifloxystrobin on soil microorganisms were integrally investigated. The results showed that trifloxystrobin inhibited urease activity, promoted dehydrogenase activity. Downregulated expressions of the nitrifying gene (amoA), denitrifying genes (nirK and nirS), and carbon fixation gene (cbbL) were also observed. Soil bacterial community structure analysis showed that trifloxystrobin changed the abundance of bacteria genera related to nitrogen and carbon cycle in soil. Through the comprehensive analysis of soil enzymes, functional gene abundance, and soil bacterial community structure, we concluded that trifloxystrobin inhibited both nitrification and denitrification of soil microorganisms, and also diminished the carbon-sequestration ability. Integrated biomarker response analysis showed that dehydrogenase and nifH were the most sensitive indicators of trifloxystrobin exposure. It provides new insights about trifloxystrobin environmental pollution and its influence on soil ecosystem.
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Affiliation(s)
- Zongyuan Xiao
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian 271018, China.
| | - Kaixuan Hou
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian 271018, China.
| | - Tongtong Zhou
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian 271018, China.
| | - Jingwen Zhang
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian 271018, China.
| | - Bing Li
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian 271018, China.
| | - Zhongkun Du
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian 271018, China.
| | - Shujuan Sun
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian 271018, China.
| | - Lusheng Zhu
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian 271018, China
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Karpouzas DG, Vryzas Z, Martin-Laurent F. Pesticide soil microbial toxicity: setting the scene for a new pesticide risk assessment for soil microorganisms (IUPAC Technical Report). PURE APPL CHEM 2022. [DOI: 10.1515/pac-2022-0201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Pesticides constitute an integral part of modern agriculture. However, there are still concerns about their effects on non-target organisms. To address this the European Commission has imposed a stringent regulatory scheme for new pesticide compounds. Assessment of the aquatic toxicity of pesticides is based on a range of advanced tests. This does not apply to terrestrial ecosystems, where the toxicity of pesticides on soil microorganisms, is based on an outdated and crude test (N mineralization). This regulatory gap is reinforced by the recent methodological and standardization advances in soil microbial ecology. The inclusion of such standardized tools in a revised risk assessment scheme will enable the accurate estimation of the toxicity of pesticides on soil microorganisms and on associated ecosystem services. In this review we (i) summarize recent work in the assessment of the soil microbial toxicity of pesticides and point to ammonia-oxidizing microorganisms (AOM) and arbuscular mycorrhizal fungi (AMF) as most relevant bioindicator groups (ii) identify limitations in the experimental approaches used and propose mitigation solutions, (iii) identify scientific gaps and (iv) propose a new risk assessment procedure to assess the effects of pesticides on soil microorganisms.
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Affiliation(s)
- Dimitrios G. Karpouzas
- Department of Biochemistry and Biotechnology , Laboratory of Plant and Environmental Biotechnology, University of Thessaly , Viopolis 41500 , Larissa , Greece
| | - Zisis Vryzas
- Department of Agricultural Development , Democritus University of Thrace , Orestiada , Greece
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Li Y, Li Q, Chen S. Diazotroph Paenibacillus triticisoli BJ-18 Drives the Variation in Bacterial, Diazotrophic and Fungal Communities in the Rhizosphere and Root/Shoot Endosphere of Maize. Int J Mol Sci 2021; 22:1460. [PMID: 33540521 PMCID: PMC7867140 DOI: 10.3390/ijms22031460] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 12/28/2022] Open
Abstract
Application of diazotrophs (N2-fixing microorganisms) can decrease the overuse of nitrogen (N) fertilizer. Until now, there are few studies on the effects of diazotroph application on microbial communities of major crops. In this study, the diazotrophic and endospore-forming Paenibacillus triticisoli BJ-18 was inoculated into maize soils containing different N levels. The effects of inoculation on the composition and abundance of the bacterial, diazotrophic and fungal communities in the rhizosphere and root/shoot endosphere of maize were evaluated by sequencing the 16S rRNA, nifH gene and ITS (Inter Transcribed Spacer) region. P. triticisoli BJ-18 survived and propagated in all the compartments of the maize rhizosphere, root and shoot. The abundances and diversities of the bacterial and diazotrophic communities in the rhizosphere were significantly higher than in both root and shoot endospheres. Each compartment of the rhizosphere, root and shoot had its specific bacterial and diazotrophic communities. Our results showed that inoculation reshaped the structures of the bacterial, diazotrophic and fungal communities in the maize rhizosphere and endosphere. Inoculation reduced the interactions of the bacteria and diazotrophs in the rhizosphere and endosphere, while it increased the fungal interactions. After inoculation, the abundances of Pseudomonas, Bacillus and Paenibacillus in all three compartments, Klebsiella in the rhizosphere and Paenibacillus in the root and shoot were significantly increased, while the abundances of Fusarium and Giberella were greatly reduced. Paenibacillus was significantly correlated with plant dry weight, nitrogenase, N2-fixing rate, P solubilization and other properties of the soil and plant.
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Affiliation(s)
| | | | - Sanfeng Chen
- State Key Laboratory for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Beijing 100094, China; (Y.L.); (Q.L.)
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Su X, Wang Y, Peng G, He Q. Long-term effects of chlorothalonil on microbial denitrification and N 2O emission in a tea field soil. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:17370-17381. [PMID: 32157531 DOI: 10.1007/s11356-020-07679-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 01/07/2020] [Indexed: 06/10/2023]
Abstract
Pesticide chlorothalonil is widely applied in tea agroecosystem, potentially disturbing soil microbial-mediated nitrogen cycle. The underlying toxicity mechanism, however, is not well explored. Here, we investigated the long-term effects of chlorothalonil on soil microbial denitrification and N2O emission pattern in a tea field after 40 days of exposure. Results showed that chlorothalonil inhibited denitrification process but remarkably promoted N2O emission by 380-830%. Chlorothalonil significantly inhibited N2O reductase activity but did not affected nosZ abundance. Our results further revealed that chlorothalonil influenced soil denitrification by directly suppressing microbial electron transport system activity, and decreasing electron donor nicotinamide adenine dinucleotide (NADH) and energy source adenosine triphosphate (ATP) levels. Additionally, chlorothalonil also downregulated denitrifying functional genes (narG, nirS, and norB) and declined the relative abundances of potential denitrifiers (i.e., Pseudomonas and Streptomyces). Stepwise regression and path modeling suggested that nitrate reductase was the most significant factor in explaining denitrification rate under chlorothalonil applications. This study provides important information for revealing the chronic impacts of pesticide on tea soil denitrification and N2O emission on the basis of electron transport mechanism. Most significantly, N2O emission is underestimated in chlorothalonil-treated soils, which suggests that future estimations of N2O emission from agricultural lands should take account of pesticide dependency conditions.
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Affiliation(s)
- Xiaoxuan Su
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, 361021, China
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
| | - Yiyu Wang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
- College of Urban Construction & Environmental Engineering, Chongqing University, 174 Shazhengjie Street, Shapingba District, Chongqing, 400045, China
| | - Guilong Peng
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Qiang He
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China.
- College of Urban Construction & Environmental Engineering, Chongqing University, 174 Shazhengjie Street, Shapingba District, Chongqing, 400045, China.
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7
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Han L, Liu Y, Fang K, Zhang X, Liu T, Wang F, Wang X. Dissipation of chlorothalonil in the presence of chlortetracycline and ciprofloxacin and their combined effects on soil enzyme activity. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:13662-13669. [PMID: 32030591 DOI: 10.1007/s11356-020-07753-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 01/14/2020] [Indexed: 06/10/2023]
Abstract
The long-term application of substantial amounts of fungicides and antibiotic-polluted organic manure (OM) in greenhouse has caused the co-existence of fungicides and antibiotics in soils. However, little is known about the effects of antibiotics on the persistence of fungicides in soils or their combined effects on soil enzyme activity. In this study, fungicide chlorothalonil (CTL) alone and in combination with antibiotic chlortetracycline (CTC) or ciprofloxacin (CIP) were repeatedly added to OM-amended soil to investigate the changes in the residual characteristics of CTL and in soil dehydrogenase and urease activity. The results showed that CTL rapidly dissipated in soils with the corresponding half-lives of 0.9-3.2, which initially increased, then decreased and finally stabilized with an increased treatment frequency. The dissipation of CTL was inhibited by CTC and CIP during the first several treatments. The soil dehydrogenase and urease activity in CTL-treated soils was inhibited during the first six treatments and then recovered afterwards. Compared with the OM-amended soil+CTL treatment, the OM-amended soil+CTL+CTC and OM-amended soil+CTL+CIP treatments had stronger inhibitory effects on soil enzyme activity during the first six repeated treatments but exhibited slight stimulating effects afterwards. Therefore, the results obtained in this study suggested that the long-term co-existence of CTL, CTC, and CIP altered the dissipation characteristics of CTL in soil and affected the soil enzyme activity levels. The prudent application of large and frequent of fungicides and OM-containing antibiotic residues in greenhouses should therefore be carefully considered in order to reduce the long-term combined pollution in soils.
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Affiliation(s)
- Lingxi Han
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences (CAAS), Qingdao, 266101, People's Republic of China
| | - Yalei Liu
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences (CAAS), Qingdao, 266101, People's Republic of China
| | - Kuan Fang
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences (CAAS), Qingdao, 266101, People's Republic of China
| | - Xiaolian Zhang
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences (CAAS), Qingdao, 266101, People's Republic of China
| | - Tong Liu
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences (CAAS), Qingdao, 266101, People's Republic of China
| | - Fenglong Wang
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences (CAAS), Qingdao, 266101, People's Republic of China.
| | - Xiuguo Wang
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences (CAAS), Qingdao, 266101, People's Republic of China.
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Zhang Q, Liu H, Saleem M, Wang C. Biotransformation of chlorothalonil by strain Stenotrophomonas acidaminiphila BJ1 isolated from farmland soil. ROYAL SOCIETY OPEN SCIENCE 2019; 6:190562. [PMID: 31827822 PMCID: PMC6894561 DOI: 10.1098/rsos.190562] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 10/03/2019] [Indexed: 06/10/2023]
Abstract
Chlorothalonil is a widely used fungicide, but the contamination of soil and water environments by this chemical causes potential threats to biodiversity. Given the metabolic potential of soil microorganisms, there is a need for developing microbiological approaches to degrade persistent compounds, such as chlorothalonil, in contaminated sites. Here in this study, we isolated a bacterial strain (namely, BJ1) capable of degrading chlorothalonil from a chlorothalonil-contaminated farmland soil in the Shandong Province, China. Using 16S rDNA gene sequencing, morphological and biological characteristics, we identified the strain BJ1 as Stenotrophomonas acidaminiphila. The strain BJ1 uses chlorothalonil as a sole carbon source. At initial concentrations of 50, 100, 200 and 300 mg l-1, it degraded 91.5%, 89.4%, 86.5% and 83.5% of chlorothalonil after 96 h of inoculation under optimum conditions (30°C and pH 7.0). Two metabolites, methyl-2,5,6-trichloro-3-cyano-4-methoxy-benzoate and methyl-3-cyano-2,4,5,6-tetrachlorobenzoate, were detected and identified based on HPLC-MS analysis, which suggests that the strain BJ1 metabolized chlorothalonil through the hydroxylation of chloro-group and hydration of cyano-group. The results of this study highlight the great potential for this bacterium to be used in chlorothalonil pollution remediation.
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Affiliation(s)
- Qingming Zhang
- Key Lab of Integrated Crop Pest Management of Shandong Province, College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao 266109, People's Republic of China
| | - Hongyu Liu
- Key Lab of Integrated Crop Pest Management of Shandong Province, College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao 266109, People's Republic of China
| | - Muhammad Saleem
- Department of Biological Sciences, Alabama State University, Montgomery, AL 36101, USA
| | - Caixia Wang
- Key Lab of Integrated Crop Pest Management of Shandong Province, College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao 266109, People's Republic of China
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Hu X, Wang Y, Su X, Chen Y. Acute response of soil denitrification and N 2O emissions to chlorothalonil: A comprehensive molecular mechanism. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 636:1408-1415. [PMID: 29913601 DOI: 10.1016/j.scitotenv.2018.04.378] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 04/27/2018] [Accepted: 04/27/2018] [Indexed: 06/08/2023]
Abstract
The fungicide chlorothalonil (CHT) has been widely used in the tea orchard due to its high-efficiency and sterilization. It has been reported that repeated application of CHT inhibits soil nitrification process. However, the acute impact of CHT on soil denitrification and associated N2O emissions is unclear. This study evaluated nitrate (NO3-) removal, denitrifying gene abundance and denitrifying enzyme activity of tea orchard soil after a 72-h-exposure to CHT. It was found that increasing CHT from 5 to 25 mg kg-1 suppressed the NO3- removal efficiency from 74.6% to 54.1%, but increased N2O emissions from 23.1% to 94.8%. Following treatment with 25 mg kg-1 of CHT, the abundances of the nirK, nirS and nosZ genes were reduced by 31.6%, 22.1%, and 50.7%, respectively. Alternatively, the declines of the electron transport system activity (ETSA) value and adenosine triphosphate (ATP) content suggested that CHT had an inhibitory effect on microbial metabolism. Enzyme activity studies further revealed that the decrease of nitrate reductase (NAR), nitrite reductase (NIR) and nitric oxide reductase (NOR) activities was the main reason for the suppression of denitrification by CHT. Furthermore, positive correlations were observed between denitrifying reductase activity and the intracellular metabolism, indicating that the decrease in microbial metabolism should also be responsible for the inhibitory effect of CHT on the denitrifying process. Overall, it was found that the acute exposure of soil to CHT could inhibit the denitrification process and significantly increase N2O emissions, which might result in destruction of the soil nitrogen cycle and exacerbation of global warming.
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Affiliation(s)
- Xuebin Hu
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Yiyu Wang
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Xiaoxuan Su
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Yi Chen
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China.
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Zhang Q, Saleem M, Wang C. Probiotic strain Stenotrophomonas acidaminiphila BJ1 degrades and reduces chlorothalonil toxicity to soil enzymes, microbial communities and plant roots. AMB Express 2017; 7:227. [PMID: 29275520 PMCID: PMC5742092 DOI: 10.1186/s13568-017-0530-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 12/19/2017] [Indexed: 11/10/2022] Open
Abstract
Chlorothalonil, a non-systemic and broad-spectrum fungicide, is widely used to control the pathogens of agricultural plants. Although microbial degradation of chlorothalonil is known, we know little about the colonization and degradation capacity of these microbes in the natural and semi-natural soil environments. Therefore, we studied the colonization and detoxification potential of a chlorothalonil degrading Stenotrophomonas acidaminiphila probiotic strain BJ1 in the soil under green conditions. The results from polymerase chain reaction-denaturing gradient gel electrophoresis demonstrated that probiotic strain BJ1 successfully colonized the soil by competing with the native biota. Moreover, the bacterial inoculation stimulated some members of indigenous soil microbial communities. Meantime, the degradation half-life of chlorothalonil decreased from 9.0 to 4.9 days in the soil environment. Moreover, the results from enzymatic activities and micronucleus test of Vicia faba root tips showed that the probiotic strain BJ1 reduced the ecotoxicity and genotoxicity of chlorothalonil in the soil. We suggest that probiotic strains like BJ1 could potentially alleviate the toxic effects of pesticides on soil microbes and plant roots under greenhouse conditions.
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