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Vincent CV, Bignell DRD. Regulation of virulence mechanisms in plant-pathogenic Streptomyces. Can J Microbiol 2024; 70:199-212. [PMID: 38190652 DOI: 10.1139/cjm-2023-0171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2024]
Abstract
Streptomyces have a uniquely complex developmental life cycle that involves the coordination of morphological differentiation with the production of numerous bioactive specialized metabolites. The majority of Streptomyces spp. are soil-dwelling saprophytes, while plant pathogenicity is a rare attribute among members of this genus. Phytopathogenic Streptomyces are responsible for economically important diseases such as common scab, which affects potato and other root crops. Following the acquisition of genes encoding virulence factors, Streptomyces pathogens are expected to have specifically adapted their regulatory pathways to enable transition from a primarily saprophytic to a pathogenic lifestyle. Investigations of the regulation of pathogenesis have primarily focused on Streptomyces scabiei and the principal pathogenicity determinant thaxtomin A. The coordination of growth and thaxtomin A production in this species is controlled in a hierarchical manner by cluster-situated regulators, pleiotropic regulators, signalling and plant-derived molecules, and nutrients. Although the majority of phytopathogenic Streptomyces produce thaxtomins, many also produce additional virulence factors, and there are scab-causing pathogens that do not produce thaxtomins. The development of effective control strategies for common scab and other Streptomyces plant diseases requires a more in-depth understanding of the genetic and environmental factors that modulate the plant pathogenic lifestyle of these organisms.
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Affiliation(s)
- Corrie V Vincent
- Department of Biology, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Dawn R D Bignell
- Department of Biology, Memorial University of Newfoundland, St. John's, NL, Canada
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Cui L, Yang C, Jin M, Wei L, Yang L, Zhou J. Identification and biological characterization of a new pathogen that causes potato scab in Gansu Province, China. Microb Pathog 2021; 161:105276. [PMID: 34728371 DOI: 10.1016/j.micpath.2021.105276] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 10/28/2021] [Accepted: 10/29/2021] [Indexed: 10/19/2022]
Abstract
Potato scab caused by pathogenic Streptomyces is a serious soil-borne disease on potato. In this study, a new Streptomyces strain 5A-1 was isolated from potato samples in China. Based on morphological characteristics, 16S rDNA gene sequence analyses, it was identified as Streptomyces griseoplanus (Streptacidiphilus griseoplanus), pathogenicity of which was measured by the methods of small potato chips, radish slices and potato pot trial inoculation. Moreover, the pathogenic genes txtAB and tomA from the Streptomyces pathogenicity island (PAI) were detected. Determination of biological characteristics showed that the optimal temperature for the growth of S. griseoplanus strain 5A-1 was 25 °C, the optimal light condition was darkness, the optimal pH value was 8.5 and the most preferred carbon source and nitrogen source is glucose and aspartate, respectively. To our knowledge, it is the first report for S. griseoplanus, as a new pathogen, to cause potato scab.
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Affiliation(s)
- Lingxiao Cui
- Laboratory of Biocontrol Engineering of Crop Pests and Diseases in Gansu Province, College of Plant Protection, Gansu Agricultural University, Lanzhou, 730070, China
| | - Chengde Yang
- Laboratory of Biocontrol Engineering of Crop Pests and Diseases in Gansu Province, College of Plant Protection, Gansu Agricultural University, Lanzhou, 730070, China.
| | - Mengjun Jin
- Laboratory of Biocontrol Engineering of Crop Pests and Diseases in Gansu Province, College of Plant Protection, Gansu Agricultural University, Lanzhou, 730070, China
| | - Lijuan Wei
- Laboratory of Biocontrol Engineering of Crop Pests and Diseases in Gansu Province, College of Plant Protection, Gansu Agricultural University, Lanzhou, 730070, China
| | - Liping Yang
- Laboratory of Biocontrol Engineering of Crop Pests and Diseases in Gansu Province, College of Plant Protection, Gansu Agricultural University, Lanzhou, 730070, China
| | - Jingjiang Zhou
- Laboratory of Biocontrol Engineering of Crop Pests and Diseases in Gansu Province, College of Plant Protection, Gansu Agricultural University, Lanzhou, 730070, China; State Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxin District, Guiyang, 550025, China
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Isolation of Actinomycetes with Cellulolytic and Antimicrobial Activities from Soils Collected from an Urban Green Space in the Philippines. Int J Microbiol 2021; 2021:6699430. [PMID: 33815506 PMCID: PMC7990538 DOI: 10.1155/2021/6699430] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 02/12/2021] [Accepted: 02/25/2021] [Indexed: 11/17/2022] Open
Abstract
Actinomycetes are one of the most important groups of soil bacteria that are recognized as sources of commercially important enzymes and antimicrobials. Actinomycetes, however, are largely underestimated and uncharacterized in underexplored habitats such as green spaces in urban areas. This study aimed to isolate actinomycetes from soils in the University of the Philippines Diliman campus and determine their cellulolytic and antimicrobial activities. A total of 235 isolates were purified from the soil samples collected. Cellulolytic and antimicrobial activities were observed in 114 and 18 isolates, respectively. The cell-free supernatants of 31 isolates exhibited high cellulolytic activities. Two isolates, in particular EWLG2 and EPNA9, had 0.596 FPU and 0.885 FPU cellulolytic activity, respectively. Seven isolates exhibited antimicrobial activities in the screening methods used. The crude extracts of isolates AWLG9, AWLG8, AWLG10, AULG1, APLG2, and AWLG13 had minimum inhibitory concentrations (MIC) values ranging from 31.25 µg/mL to 500 µg/mL against Candida spp. Isolates AULG1 and EPLG5 were active against the bacterial test microorganisms and had MIC values ranging from 250 µg/mL to 500 µg/mL. DNA sequencing identified the isolates which exhibited high cellulolytic and antimicrobial activities as Bacillus sp. and Streptomyces sp., with percent identities ≥98%. This study shows that green spaces are rich sources of soil microorganisms that have cellulolytic and antimicrobial activities. It is recommended that the isolates obtained in this study be examined further for possible applications in bioethanol production and pharmacology.
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Zhang XY, Li C, Hao JJ, Li YC, Li DZ, Zhang DM, Xing X, Liang Y. A Novel Streptomyces sp. Strain PBSH9 for Controlling Potato Common Scab Caused by Streptomyces galilaeus. PLANT DISEASE 2020; 104:1986-1993. [PMID: 32441579 DOI: 10.1094/pdis-07-19-1469-re] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Potato common scab is an important soilborne disease worldwide that can significantly reduce the quality and economic values of potato. The disease is caused by multiple species of Streptomyces, which are not well controlled due to lack of effective strategies. Streptomyces galilaeus has been recently identified as a dominant species causing potato common scab in Inner Mongolia, China. This study was focused on screening and characterizing antagonists for biological control against pathogenic S. galilaeus. Bacterial strain PBSH9 was isolated from a potato tuber. PBSH9 was identified as a Streptomyces sp. on the basis of morphological, physiological, and biochemical characteristics, as well as DNA sequence analysis. PBSH9 inhibited S. galilaeus with a diameter of inhibitory zone of 19.8 mm on agar plates. The extracellular filtrate of PBSH9 also inhibited S. galilaeus growth with a diameter of inhibition zone of 10.0 mm. Furthermore, PBSH9 promoted potato sprouting and emergence. Disease control was up to 81.88% in greenhouse trials, and from 47.64 to 73.97% in 3-year field trials. Among the tested inoculation methods, seed treatment was more effective than soil drenching for PBSH9 application. PBSH9 not only effectively controlled potato common scab but also increased potato growth. Thus, it can be a potential candidate for biocontrol agent.
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Affiliation(s)
- Xiao-Yu Zhang
- College of Horticulture and Plant Protection, Inner Mongolia Agricultural University, Hohhot 010019, China
| | - Chi Li
- College of Horticulture and Plant Protection, Inner Mongolia Agricultural University, Hohhot 010019, China
| | - Jian-Jun Hao
- School of Food and Agriculture, University of Maine, Orono, ME 04469, U.S.A
| | - Yu-Chen Li
- College of Horticulture and Plant Protection, Inner Mongolia Agricultural University, Hohhot 010019, China
| | - De-Zhou Li
- College of Horticulture and Plant Protection, Inner Mongolia Agricultural University, Hohhot 010019, China
- Development Planning Office, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Dong-Mei Zhang
- College of Horticulture and Plant Protection, Inner Mongolia Agricultural University, Hohhot 010019, China
| | - Xing Xing
- College of Horticulture and Plant Protection, Inner Mongolia Agricultural University, Hohhot 010019, China
| | - Yan Liang
- College of Horticulture and Plant Protection, Inner Mongolia Agricultural University, Hohhot 010019, China
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Liang F, Lin R, Yao Y, Xiao Y, Zhang M, Shi C, He X, Zhou B, Wang B. Systematic Identification of Pathogenic Streptomyces sp. AMCC400023 That Causes Common Scab and Genomic Analysis of Its Pathogenicity Island. PHYTOPATHOLOGY 2019; 109:1115-1128. [PMID: 30829555 DOI: 10.1094/phyto-07-18-0266-r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Potato scab, a serious soilborne disease caused by Streptomyces spp., occurs in potato-growing areas worldwide and results in severe economic losses. In this paper, the pathogenicity of Streptomyces strain AMCC400023, isolated from potato scabs in Hebei Province, China, was verified systematically by the radish seedling test, the potato tuber slice assay, the potted back experiment, and the detection of phytotoxin thaxtomin A. Morphological, physiological, and biochemical characteristics were determined, and the 16S ribosomal RNA analyses of Streptomyces sp. AMCC400023 were carried out. To obtain the accurate taxonomic status of the pathogen strain, the whole genome was sequenced, and the phylogenetic tree among 31 Streptomyces genomes was formed. The average nucleotide identity (ANI) and in silico DNA-DNA hybridization (isDDH) were analyzed, and at the same time, the toxicity-related genes between Streptomyces sp. AMCC400023 and Streptomyces scabiei were compared, all based on the whole-genome level. All of the data supported that, instead of a member of S. scabiei, test strain Streptomyces sp. AMCC400023 was a distinct phytopathogen of potato common scab, which had a relatively close relationship with S. scabiei while separating clearly from S. scabiei at least in the species level of taxonomic status. The complete pathogenicity island (PAI) composition of Streptomyces sp. AMCC400023 was identified, which contained a toxin region and a colonization region. It was conjectured that the PAI of Streptomyces sp. AMCC400023 might be directly or indirectly acquired from S. scabiei 87-22 by horizontal gene transfer, or at the very least, there was a very close homologous relationship between the two pathogens as indicated by a series of analyses, such as phylogenetic relationships among 31 Streptomyces species, ANI and isDDH analyses, PAI structure mapping, thaxtomin A synthetic gene cluster tree construction, and most important, the collinearity analysis at the genome level.
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Affiliation(s)
- Feiyang Liang
- 1 Department of Microbiology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, People's Republic of China
| | - Rongshan Lin
- 1 Department of Microbiology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, People's Republic of China
| | - Yaqian Yao
- 1 Department of Microbiology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, People's Republic of China
| | | | - Mingshuo Zhang
- 1 Department of Microbiology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, People's Republic of China
| | - Chunyu Shi
- 3 Agricultural College, Shandong Agricultural University, Tai'an 271018, People's Republic of China
| | - Xiaoli He
- 1 Department of Microbiology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, People's Republic of China
| | - Bo Zhou
- 1 Department of Microbiology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, People's Republic of China
- 4 National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Tai'an 271018, People's Republic of China
| | - Bing Wang
- 1 Department of Microbiology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, People's Republic of China
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Xu XN, Chen LY, Chen C, Tang YJ, Bai FW, Su C, Zhao XQ. Genome Mining of the Marine Actinomycete Streptomyces sp. DUT11 and Discovery of Tunicamycins as Anti-complement Agents. Front Microbiol 2018; 9:1318. [PMID: 29973921 PMCID: PMC6019454 DOI: 10.3389/fmicb.2018.01318] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Accepted: 05/30/2018] [Indexed: 12/17/2022] Open
Abstract
Marine actinobacteria are potential producers of various secondary metabolites with diverse bioactivities. Among various bioactive compounds, anti-complement agents have received great interest for drug discovery to treat numerous diseases caused by inappropriate activation of the human complement system. However, marine streptomycetes producing anti-complement agents are still poorly explored. In this study, a marine-derived strain Streptomyces sp. DUT11 showing superior anti-complement activity was focused, and its genome sequence was analyzed. Gene clusters showing high similarities to that of tunicamycin and nonactin were identified, and their corresponding metabolites were also detected. Subsequently, tunicamycin I, V, and VII were isolated from Streptomyces sp. DUT11. Anti-complement assay showed that tunicamycin I, V, VII inhibited complement activation through the classic pathway, whereas no anti-complement activity of nonactin was detected. This is the first time that tunicamycins are reported to have such activity. In addition, genome analysis indicates that Streptomyces sp. DUT11 has the potential to produce novel lassopeptides and lantibiotics. These results suggest that marine Streptomyces are rich sources of anti-complement agents for drug discovery.
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Affiliation(s)
- Xiao-Na Xu
- School of Life Sciences and Biotechnology, Dalian University of Technology, Dalian, China
| | - Liang-Yu Chen
- School of Life Sciences and Biotechnology, Dalian University of Technology, Dalian, China
| | - Chao Chen
- College of Life Science, Dalian Minzu University, Dalian, China
| | - Ya-Jie Tang
- Key Laboratory of Fermentation Engineering, Ministry of Education – Hubei Provincial Cooperative Innovation Center of Industrial Fermentation, Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan, China
| | - Feng-Wu Bai
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Chun Su
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, College of Life Sciences, Shaanxi Normal University, Xi’an, China
| | - Xin-Qing Zhao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
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A whole genome analysis reveals the presence of a plant PR1 sequence in the potato pathogen Streptomyces scabies and other Streptomyces species. Mol Phylogenet Evol 2016; 114:346-352. [PMID: 27530704 DOI: 10.1016/j.ympev.2016.08.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 08/01/2016] [Accepted: 08/11/2016] [Indexed: 11/23/2022]
Abstract
Streptomyces scabies is a common soil bacterium that causes scab symptoms in potatoes. Strong evidence indicates horizontal gene transfer (HGT) among bacteria has influenced the evolution of this plant pathogen and other Streptomyces spp. To extend the study of the HGT to the Streptomyces genus, we explored the effects of the inter-domain HGT in the S. scabies genome. We employed a semi-automatic pipeline based on BLASTp searches and phylogenetic reconstruction. The data show low impact of inter-domain HGT in the S. scabies genome; however, we found a putative plant pathogenesis related 1 (PR1) sequence in the genome of S. scabies and other species of the genus. It is possible that this gene could be used by S. scabies to out-compete other soil organisms.
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Fyans JK, Bown L, Bignell DRD. Isolation and Characterization of Plant-Pathogenic Streptomyces Species Associated with Common Scab-Infected Potato Tubers in Newfoundland. PHYTOPATHOLOGY 2016; 106:123-131. [PMID: 26524546 DOI: 10.1094/phyto-05-15-0125-r] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Potato common scab (CS) is an economically important crop disease that is caused by several members of the genus Streptomyces. In this study, we characterized the plant-pathogenic Streptomyces spp. associated with CS-infected potato tubers harvested in Newfoundland, Canada. A total of 17 pathogenic Streptomyces isolates were recovered from potato scab lesions, of which eight were determined to be most similar to the known CS pathogen S. europaeiscabiei. All eight S. europaeiscabiei isolates were found to produce the thaxtomin A phytotoxin and to harbor the nec1 virulence gene, and most also carry the putative virulence gene tomA. The remaining isolates appear to be novel pathogenic species that do not produce thaxtomin A, and only two of these isolates were determined to harbor the nec1 or tomA genes. Of the non-thaxtomin-producing isolates, strain 11-1-2 was shown to exhibit a severe pathogenic phenotype against different plant hosts and to produce a novel, secreted phytotoxic substance. This is the first report documenting the plant-pathogenic Streptomyces spp. associated with CS disease in Newfoundland. Furthermore, our findings provide further evidence that phytotoxins other than thaxtomin A may also contribute to the development of CS by Streptomyces spp.
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Affiliation(s)
- Joanna K Fyans
- Department of Biology, Memorial University of Newfoundland, St. John's, NL, A1B 3X9, Canada
| | - Luke Bown
- Department of Biology, Memorial University of Newfoundland, St. John's, NL, A1B 3X9, Canada
| | - Dawn R D Bignell
- Department of Biology, Memorial University of Newfoundland, St. John's, NL, A1B 3X9, Canada
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Bignell D, Fyans J, Cheng Z. Phytotoxins produced by plant pathogenic Streptomyces
species. J Appl Microbiol 2013; 116:223-35. [DOI: 10.1111/jam.12369] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Revised: 10/11/2013] [Accepted: 10/12/2013] [Indexed: 01/18/2023]
Affiliation(s)
- D.R.D. Bignell
- Department of Biology; Memorial University of Newfoundland; St. John's NL Canada
| | - J.K. Fyans
- Department of Biology; Memorial University of Newfoundland; St. John's NL Canada
| | - Z. Cheng
- Department of Biology; Memorial University of Newfoundland; St. John's NL Canada
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Meng QX, Jiang HH, Hanson LE, Hao JJ. Characterizing a novel strain of Bacillus amyloliquefaciens BAC03 for potential biological control application. J Appl Microbiol 2012; 113:1165-75. [PMID: 22924833 DOI: 10.1111/j.1365-2672.2012.05420.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Revised: 06/21/2012] [Accepted: 07/30/2012] [Indexed: 11/27/2022]
Abstract
AIMS To identify and characterize a bacterial strain BAC03, evaluate its biological control activity against potato common scab (Streptomyces spp.) and characterize an antimicrobial substance produced by BAC03. METHODS AND RESULTS Bacterial strain BAC03, isolated from potato common scab suppressive soil, was identified as Bacillus amyloliquefaciens by analysing sequences of fragments of the recA, recN, cheA and gyrA genes. BAC03 displayed an antagonistic activity against Streptomyces spp. on agar plates using a co-culture method. In glasshouse assays, BAC03 applied in potting mix significantly reduced common scab severity (P < 0·05) and potentially increased the growth of potato plants (P < 0·05). An antimicrobial substance extracted from BAC03 by ammonium sulfate precipitation was identified as an LCI protein using liquid chromatography-mass spectrometry. The antimicrobial activity of either a BAC03 liquid culture or the ammonium sulfate precipitate fraction was stable under a wide range of temperatures, and pH levels, as well as following incubation with several chemicals, but was reduced by all proteinases tested. CONCLUSIONS Bacillus amyloliquefaciens strain BAC03 displayed a strong antimicrobial activity, that is, the suppression of potato common scab, and may potentially enhance the plant growth. LCI protein is associated with some of the antimicrobial activity. SIGNIFICANCE AND IMPACT OF THE STUDY Bacterial strain BAC03 has the potential to be developed as a commercial biological control agent for potato common scab.
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Affiliation(s)
- Q X Meng
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI, USA
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Meng Q, Yin J, Rosenzweig N, Douches D, Hao JJ. Culture-Based Assessment of Microbial Communities in Soil Suppressive to Potato Common Scab. PLANT DISEASE 2012; 96:712-717. [PMID: 30727529 DOI: 10.1094/pdis-05-11-0441] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
A field in East Lansing, MI, showed a decline of potato common scab compared with an adjacent potato field. To confirm that the decline was due to biological factors, the soil was assayed. In the greenhouse, putative common-scab-suppressive soil (SS) was either treated with various temperatures or mixed with autoclaved SS at various ratios. Pathogenic Streptomyces scabies was incorporated into the treated soil at 106 CFU/cm3 of soil, followed by planting of either potato or radish. Disease severity was negatively correlated with the percentage of SS in the mixture and positively correlated with temperature above 60°C. The soil was screened for four groups of potential antagonists (general bacteria, streptomycetes, fluorescent pseudomonads, and bacilli) pairing in culture with S. scabies. The frequency of antagonistic bacteria in SS was higher than common-scab-conducive soil (CS) in all four groups but only pseudomonads and streptomycetes were significantly higher. The population of pathogenic Streptomyces spp. in the rhizosphere of CS was significantly higher than SS. Dilution plating of CS and SS samples showed no clear trends or differences in populations of total fungi, total bacteria, streptomycetes, fluorescent pseudomonads, and bacilli but terminal restriction fragment polymorphism analysis revealed two distinct microbial communities were present in SS and CS.
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Affiliation(s)
| | | | | | | | - Jianjun J Hao
- Department of Plant Pathology, Michigan State University, East Lansing
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