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Li Q, Feng Y, Li J, Hai Y, Si L, Tan C, Peng J, Hu Z, Li Z, Li C, Hao D, Tang W. Multi-omics approaches to understand pathogenicity during potato early blight disease caused by Alternaria solani. Front Microbiol 2024; 15:1357579. [PMID: 38529180 PMCID: PMC10961351 DOI: 10.3389/fmicb.2024.1357579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 02/14/2024] [Indexed: 03/27/2024] Open
Abstract
Potato early blight (PEB), a foliar disease of potato during the growing period, caused by Alternaria sp., is common in major potato-producing areas worldwide. Effective agents to control this disease or completely resistant potato varieties are absent. Large-scale use of fungicides is limited due to possibility of increase in pathogen resistance and the requirements of ecological agriculture. In this study, we focused on the composition and infection characteristics of early blight pathogens in Yunnan Province and screened candidate pathogenesis-related pathways and genes. We isolated 85 strains of Alternaria sp. fungi from typical early blight spots in three potato-growing regions in Yunnan Province from 2018 to 2022, and identified 35 strains of Alternaria solani and 50 strains of Alternaria alternata by morphological characterization and ITS sequence comparison, which were identified as the main and conditional pathogens causing early blight in potato, respectively. Scanning electron microscope analysis confirmed only A. solani producing appressorium at 4 h after inoculation successfully infected the leaf cells. Via genome assembly and annotation, combine transcriptome and proteomic analysis, the following pathogenicity-related unit, transcription factors and metabolic pathway were identified: (1) cell wall-degrading enzymes, such as pectinase, keratinase, and cellulase; (2) genes and pathways related to conidia germination and pathogenicity, such as ubiquitination and peroxisomes; and (3) transcription factors, such as Zn-clus, C2H2, bZIP, and bHLH. These elements were responsible for PEB epidemic in Yunnan.
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Affiliation(s)
- Qing Li
- Yunnan Key Laboratory of Potato Biology, Yunnan Normal University, Kunming, China
- School of Life Sciences, Yunnan Normal University, Kunming, China
| | - Yan Feng
- School of Economics and Management, Yunnan Normal University, Kunming, China
| | - Jianmei Li
- Yunnan Key Laboratory of Potato Biology, Yunnan Normal University, Kunming, China
- School of Life Sciences, Yunnan Normal University, Kunming, China
| | - Yang Hai
- Yunnan YinMore Modern Agriculture Co., Ltd., Kunming, China
| | - Liping Si
- Yunnan YinMore Modern Agriculture Co., Ltd., Kunming, China
| | - Chen Tan
- School of Life Sciences, Yunnan Normal University, Kunming, China
| | - Jing Peng
- School of Life Sciences, Yunnan Normal University, Kunming, China
| | - Zuo Hu
- Zhaotong Academy of Agricultural Sciences, Zhaotong, China
| | - Zhou Li
- Zhaotong Academy of Agricultural Sciences, Zhaotong, China
| | - Canhui Li
- Yunnan Key Laboratory of Potato Biology, Yunnan Normal University, Kunming, China
- School of Life Sciences, Yunnan Normal University, Kunming, China
| | - Dahai Hao
- Yunnan Key Laboratory of Potato Biology, Yunnan Normal University, Kunming, China
- School of Life Sciences, Yunnan Normal University, Kunming, China
| | - Wei Tang
- Yunnan Key Laboratory of Potato Biology, Yunnan Normal University, Kunming, China
- School of Life Sciences, Yunnan Normal University, Kunming, China
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Schmey T, Tominello-Ramirez CS, Brune C, Stam R. Alternaria diseases on potato and tomato. MOLECULAR PLANT PATHOLOGY 2024; 25:e13435. [PMID: 38476108 DOI: 10.1111/mpp.13435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 01/27/2024] [Accepted: 01/29/2024] [Indexed: 03/14/2024]
Abstract
Alternaria spp. cause different diseases in potato and tomato crops. Early blight caused by Alternaria solani and brown spot caused by Alternaria alternata are most common, but the disease complex is far more diverse. We first provide an overview of the Alternaria species infecting the two host plants to alleviate some of the confusion that arises from the taxonomic rearrangements in this fungal genus. Highlighting the diversity of Alternaria fungi on both solanaceous hosts, we review studies investigating the genetic diversity and genomes, before we present recent advances from studies elucidating host-pathogen interactions and fungicide resistances. TAXONOMY Kingdom Fungi, Phylum Ascomycota, Class Dothideomycetes, Order Pleosporales, Family Pleosporaceae, Genus Alternaria. BIOLOGY AND HOST RANGE Alternaria spp. adopt diverse lifestyles. We specifically review Alternaria spp. that cause disease in the two solanaceous crops potato (Solanum tuberosum) and tomato (Solanum lycopersicum). They are necrotrophic pathogens with no known sexual stage, despite some signatures of recombination. DISEASE SYMPTOMS Symptoms of the early blight/brown spot disease complex include foliar lesions that first present as brown spots, depending on the species with characteristic concentric rings, which eventually lead to severe defoliation and considerable yield loss. CONTROL Good field hygiene can keep the disease pressure low. Some potato and tomato cultivars show differences in susceptibility, but there are no fully resistant varieties known. Therefore, the main control mechanism is treatment with fungicides.
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Affiliation(s)
- Tamara Schmey
- TUM School of Life Science Weihenstephan, Technical University of Munich, Freising, Germany
| | - Christopher S Tominello-Ramirez
- Department of Phytopathology and Crop Protection, Institute of Phytopathology, Christian Albrechts University, Kiel, Germany
| | - Carolin Brune
- TUM School of Life Science Weihenstephan, Technical University of Munich, Freising, Germany
| | - Remco Stam
- Department of Phytopathology and Crop Protection, Institute of Phytopathology, Christian Albrechts University, Kiel, Germany
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Bai X, Li Q, Zhang D, Zhao Y, Zhao D, Pan Y, Wang J, Yang Z, Zhu J. Bacillus velezensis Strain HN-Q-8 Induced Resistance to Alternaria solani and Stimulated Growth of Potato Plant. BIOLOGY 2023; 12:856. [PMID: 37372140 DOI: 10.3390/biology12060856] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/04/2023] [Accepted: 06/05/2023] [Indexed: 06/29/2023]
Abstract
Bacillus velezensis HN-Q-8, isolated in our previous study, has an antagonistic effect on Alternaria solani. After being pretreated with a fermentation liquid with HN-Q-8 bacterial cell suspensions, the potato leaves inoculated with A. solani displayed smaller lesion areas and less yellowing than the controls. Interestingly, the activity levels of superoxide dismutase, peroxidase, and catalase in potato seedlings were enhanced by the addition of the fermentation liquid with bacterial cells. Additionally, the overexpression of key genes related to induced resistance in the Jasmonate/Ethylene pathway was activated by the addition of the fermentation liquid, suggesting that the HN-Q-8 strain induced resistance to potato early blight. In addition, our laboratory and field experiments showed that the HN-Q-8 strain can promote potato seedling growth and significantly increase tuber yield. The root activity and chlorophyll content of potato seedlings were significantly increased along with the levels of indole acetic acid, gibberellic acid 3, and abscisic acid upon addition of the HN-Q-8 strain. The fermentation liquid with bacterial cells was more efficient in inducing disease resistance and promoting growth than bacterial cell suspensions alone or the fermentation liquid without bacterial cells. Thus, the B. velezensis HN-Q-8 strain is an effective bacterial biocontrol agent, augmenting the options available for potato cultivation.
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Affiliation(s)
- Xuefei Bai
- College of Plant Protection, Hebei Agricultural University, Baoding 071000, China
| | - Qian Li
- College of Plant Protection, Hebei Agricultural University, Baoding 071000, China
| | - Dai Zhang
- College of Plant Protection, Hebei Agricultural University, Baoding 071000, China
| | - Yi Zhao
- College of Plant Protection, Hebei Agricultural University, Baoding 071000, China
| | - Dongmei Zhao
- College of Plant Protection, Hebei Agricultural University, Baoding 071000, China
| | - Yang Pan
- College of Plant Protection, Hebei Agricultural University, Baoding 071000, China
| | - Jinhui Wang
- College of Plant Protection, Hebei Agricultural University, Baoding 071000, China
| | - Zhihui Yang
- College of Plant Protection, Hebei Agricultural University, Baoding 071000, China
| | - Jiehua Zhu
- College of Plant Protection, Hebei Agricultural University, Baoding 071000, China
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Jiang J, Guo X, Tan H, Ding M, Liu F, Yang Z, Zhu J. Transcriptome sequencing leads to an improved understanding of the infection mechanism of Alternaria solani in potato. BMC PLANT BIOLOGY 2023; 23:120. [PMID: 36859112 PMCID: PMC9976505 DOI: 10.1186/s12870-023-04103-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Accepted: 02/06/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND Alternaria solani (A. solani), the main pathogen of potato early blight, causes serious yield reductions every year. The application of fungicides is the most common and effective method of controlling Alternaria-caused diseases. The differentially expressed transcripts of A. solani infecting potato were identified, revealing a group of valuable candidate genes for a systematic analysis to increase the understanding of the molecular pathogenesis of A. solani, and providing scientific data for formulating additional measures to prevent and control potato early blight. In this study, a deep RNA-sequencing approach was applied to gain insights into A. solani pathogenesis. At 3, 4, and 5 days post inoculation (dpi), RNA samples from the susceptible potato cultivar Favorita infected with A. solani strain HWC-168, were sequenced and utilized for transcriptome analysis, and compared to the transcriptome obtained 0 dpi. RESULTS A total of 4430 (2167 upregulated, 2263 downregulated), 4736 (2312 upregulated, 2424 downregulated), and 5043 (2411 upregulated, 2632 downregulated) genes were differentially expressed 3, 4 and 5 dpi, respectively, compared with genes analysed at 0 dpi. KEGG enrichment analysis showed that genes involved in the pathways of amino acid metabolism, glucose metabolism, and enzyme activity were significantly differentially expressed at the late infection stage. Correspondingly, symptoms developed rapidly during the late stage of A. solani infection. In addition, a short time-series expression miner (STEM) assay was performed to analyse the gene expression patterns of A. solani and Profile 17 and 19 showed significant change trends 3, 4 and 5 dpi. Both profiles, but especially Profile 17, included enzymes, including transferases, oxidoreductases, hydrolases and carbohydrate-active enzymes (CAZYmes), which may play important roles in late fungal infection. Furthermore, possible candidate effectors were identified through the adopted pipelines, with 137 differentially expressed small secreted proteins identified, including some enzymes and proteins with unknown functions. CONCLUSIONS Collectively, the data presented in this study show that amino acid metabolism, and glucose metabolism pathways, and specific pathway-related enzymes may be key putative pathogenic factors, and play important roles in late stage A. solani infection. These results contribute to a broader base of knowledge of A. solani pathogenesis in potato, as indicated by the transcriptional level analysis, and provide clues for determining the effectors of A. solani infection.
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Affiliation(s)
- Jia Jiang
- College of Plant Protection, Hebei Agricultural University, Baoding, 071001, China
- Department of Plant Protection, College of Horticulture and Plant Protection, Henan University of Science and Technology, Luoyang, 471023, China
| | - Xuhao Guo
- Department of Plant Protection, College of Horticulture and Plant Protection, Henan University of Science and Technology, Luoyang, 471023, China
| | - Huanhuan Tan
- Department of Plant Protection, College of Horticulture and Plant Protection, Henan University of Science and Technology, Luoyang, 471023, China
| | - Mingya Ding
- Potato Research Institute of Weichang Manchu and Mongolian Autonomous County, Chengde, 068450, China
| | - Fangming Liu
- Potato Research Institute of Weichang Manchu and Mongolian Autonomous County, Chengde, 068450, China
| | - Zhihui Yang
- College of Plant Protection, Hebei Agricultural University, Baoding, 071001, China
| | - Jiehua Zhu
- College of Plant Protection, Hebei Agricultural University, Baoding, 071001, China.
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Zheng L, Yang P, Niu Z, Tian M, Wang J, Sun C, Zhang S, Peng Z, Zhu J, Yang Z. Dissecting in vivo responses of phytohormones to Alternaria solani infection reveals orchestration of JA- and ABA-mediated antifungal defenses in potato. HORTICULTURE RESEARCH 2022; 9:uhac188. [PMID: 37180032 PMCID: PMC10167417 DOI: 10.1093/hr/uhac188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 08/16/2022] [Indexed: 05/15/2023]
Affiliation(s)
- Lijia Zheng
- Hebei Agricultural University, College of Plant Protection, Baoding, Hebei, China, 071000
| | - Pan Yang
- Hebei Agricultural University, College of Plant Protection, Baoding, Hebei, China, 071000
| | - Zijian Niu
- Hebei Agricultural University, College of Plant Protection, Baoding, Hebei, China, 071000
| | - Mengjun Tian
- Hebei Agricultural University, College of Plant Protection, Baoding, Hebei, China, 071000
| | - Jinhui Wang
- Hebei Agricultural University, College of Plant Protection, Baoding, Hebei, China, 071000
| | - Chaofei Sun
- Hebei Agricultural University, College of Plant Protection, Baoding, Hebei, China, 071000
| | - Shuo Zhang
- Hebei Agricultural University, College of Plant Protection, Baoding, Hebei, China, 071000
| | - Zechi Peng
- Hebei Agricultural University, College of Plant Protection, Baoding, Hebei, China, 071000
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Transcriptome analysis reveals putative pathogenesis genes in Alternaria panax during infecting Panax notoginseng leaves. Genes Genomics 2022; 44:855-866. [PMID: 35622230 DOI: 10.1007/s13258-022-01241-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Accepted: 03/03/2022] [Indexed: 11/04/2022]
Abstract
BACKGROUND Alternaria panax is the causative agent of black spot disease in Panax notoginseng, which causes significant yield loss. However, the molecular mechanisms underlying its pathogenicity remain mostly unknown. OBJECTIVE We sequenced the transcriptome of A. panax during infecting P. notoginseng leaves using next-generation RNA-seq to understand the molecular aspects of black spot disease. METHODS In this study, we sequenced the A. panax transcriptome during infecting P. notoginseng leaves through next-generation sequencing to explore the pathogenesis genes that may be responsible for black spot disease on P. notoginseng. RESULT The de novo transcriptome assembly of A. panax produced 23,036 unigenes, of which 18,096 genes were functionally annotated by at least one protein database. GO enrichment analysis and KEGG pathways of differentially up-regulated genes suggest that most genes are associated with metabolic processes, catalytic activity, starch, and sucrose metabolism during infection. Many pathogenesis-associated genes, including genes encoding secreted proteins, candidate secreted effectors, cell wall degrading enzymes, transcription factors, and transporters, were up-regulated in A. panax during infection. In addition, the secondary metabolite biosynthesis genes, including cytochrome P450, and nonribosomal peptide synthetases, were also identified in this study. CONCLUSIONS Differential gene expression analysis has confirmed that A. panax infection was mainly present in the middle and final stages. The findings show that these pathogenesis-associated genes in A. panax may be critical for the P. notoginseng black spots disease.
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Zhang D, Qiang R, Zhao J, Zhang J, Cheng J, Zhao D, Fan Y, Yang Z, Zhu J. Mechanism of a Volatile Organic Compound (6-Methyl-2-Heptanone) Emitted From Bacillus subtilis ZD01 Against Alternaria solani in Potato. Front Microbiol 2022; 12:808337. [PMID: 35095815 PMCID: PMC8793485 DOI: 10.3389/fmicb.2021.808337] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 12/08/2021] [Indexed: 11/26/2022] Open
Abstract
The antagonistic mechanisms of soluble non-volatile bioactive compounds, such as proteins and lipopeptides emitted from Bacillus have been widely studied. However, there are limited studies on the antifungal mechanisms of volatile organic compounds (VOCs) produced by Bacillus against plant fungal diseases. In this study, the antagonistic mechanisms of one specific VOC, 6-methyl-2-heptanone, against Alternaria solani were investigated. To optimize the extraction conditions of headspace solid-phase microextraction, a 50/30-μm divinylbenzene/carboxen/polydimethylsiloxane fiber at 50°C for 40 min was used. For gas chromatography-mass spectrometry using a free fatty acid phase capillary column, 6-methyl-2-heptanone accounted for the highest content, at 22.27%, of the total VOCs from Bacillus subtilis ZD01, which inhibited A. solani mycelial growth strongly in vitro. Therefore, 6-methyl-2-heptanone was selected as the main active chemical to elucidate the action mechanisms against A. solani. Scanning and transmission electron microscopy analyses revealed that after exposure to an EC50 dose of 6-methyl-2-heptanone, A. solani hyphal cells had a wide range of abnormalities. 6-Methyl-2-heptanone also caused the capture of cellular fluorescent green label and the release of adenosine triphosphate (ATP) from outer membranes A. solani cells, which may enhance 6-methyl-2-heptanone ability to reach the cytoplasmic membrane. In addition, 6-methyl-2-heptanone showed strong inhibitory effect on A. solani conidial germination. It also damaged conidial internal structures, with the treated group having collapsed shrunken small vesicles as observed by transmission electron microscopy. Because 6-methyl-2-heptanone showed strong effects on mycelial integrity and conidial structure, the expression levels of related pathogenic genes in A. solani treated with 6-methyl-2-heptanone were investigated. The qRT-PCR results showed that transcriptional expression levels of slt2 and wetA genes were strongly down-regulated after exposure to 6-methyl-2-heptanone. Finally, because identifying the functions of pathogenic genes will be important for the biological control of A. solani, the wetA gene was identified as a conidia-associated gene that plays roles in regulating sporulation yield and conidial maturation. These findings provide further insights into the mechanisms of VOCs secreted by Bacillus against A. solani.
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Affiliation(s)
- Dai Zhang
- College of Plant Protection, Hebei Agricultural University, Baoding, China
| | - Ran Qiang
- College of Plant Protection, Hebei Agricultural University, Baoding, China
| | - Jing Zhao
- College of Plant Protection, Hebei Agricultural University, Baoding, China
| | - Jinglin Zhang
- Beijing Laboratory for Food Quality and Safety, Beijing Technology and Business University, Beijing, China
| | - Jianing Cheng
- Agricultural Business Training and Entrepreneurship Center, Hebei Agricultural University, Baoding, China
| | - Dongmei Zhao
- College of Plant Protection, Hebei Agricultural University, Baoding, China
| | - Yaning Fan
- College of Plant Protection, Hebei Agricultural University, Baoding, China
| | - Zhihui Yang
- College of Plant Protection, Hebei Agricultural University, Baoding, China
- *Correspondence: Zhihui Yang,
| | - Jiehua Zhu
- College of Plant Protection, Hebei Agricultural University, Baoding, China
- Jiehua Zhu,
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Jindo K, Evenhuis A, Kempenaar C, Pombo Sudré C, Zhan X, Goitom Teklu M, Kessel G. Review: Holistic pest management against early blight disease towards sustainable agriculture. PEST MANAGEMENT SCIENCE 2021; 77:3871-3880. [PMID: 33538396 PMCID: PMC8451811 DOI: 10.1002/ps.6320] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/22/2021] [Accepted: 02/04/2021] [Indexed: 05/24/2023]
Abstract
Alternaria species are well-known aggressive pathogens that are widespread globally and warmer temperatures caused by climate change might increase their abundance more drastically. Early blight (EB) disease, caused mainly by Alternaria solani, and brown spot, caused by Alternaria alternata, are major concerns in potato, tomato and eggplant production. The development of EB is strongly linked to varieties, crop development stages, environmental factors, cultivation and field management. Several forecasting models for pesticide application to control EB were created in the last century and more recent scientific advances have included modern breeding technology to detect resistant genes and precision agriculture with hyperspectral sensors to pinpoint damage locations on plants. This paper presents an overview of the EB disease and provides an evaluation of recent scientific advances to control the disease. First of all, we describe the outline of this disease, encompassing biological cycles of the Alternaria genus, favorite climate and soil conditions as well as resistant plant species. Second, versatile management practices to minimize the effect of this pathogen at field level are discussed, covering their limitations and pitfalls. A better understanding of the underlying factors of this disease and the potential of novel research can contribute to implementing integrated pest management systems for an ecofriendly farming system. © 2021 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Keiji Jindo
- Agrosystems ResearchWageningen University & ResearchWageningenThe Netherlands
| | | | - Corné Kempenaar
- Agrosystems ResearchWageningen University & ResearchWageningenThe Netherlands
| | - Cláudia Pombo Sudré
- Laboratório de Melhoramento Genético VegetalUniversidade Estadual do Norte Fluminense Darcy Ribeiro, UENFCampos dos GoytacazesBrazil
| | - Xiaoxiu Zhan
- Department of Crop Cultivation and Farming SystemCollege of Agronomy, Sichuan Agricultural UniversityChengduChina
| | | | - Geert Kessel
- Field CropsWageningen University & ResearchLelystadThe Netherlands
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Zhang D, Yu S, Yang Y, Zhang J, Zhao D, Pan Y, Fan S, Yang Z, Zhu J. Antifungal Effects of Volatiles Produced by Bacillus subtilis Against Alternaria solani in Potato. Front Microbiol 2020; 11:1196. [PMID: 32625175 PMCID: PMC7311636 DOI: 10.3389/fmicb.2020.01196] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 05/12/2020] [Indexed: 11/30/2022] Open
Abstract
Antifungal activities of plant-beneficial Bacillus have been widely studied in recent years. Numerous studies have studied the antifungal mechanisms of soluble non-volatile bioactive compounds such as lipopeptides and proteins produced by Bacillus against soil-borne diseases. However, the antagonistic mechanisms of volatile organic compounds (VOCs) from Bacillus against airborne phytopathogens are still largely unknown, and the function of Alternaria solani pathogenic genes has not been well identified. Here, we first isolated a Bacillus strain with strong antifungal activity and finally identified it as B. subtilis ZD01. Then, the antagonistic mechanisms of VOCs produced by strain ZD01, against A. solani, an airborne fungal pathogen that can cause early blight diseases of potato, were studied. We showed that VOCs produced by strain ZD01 can reduce the colony size and mycelial penetration and can cause serious morphological changes of A. solani. Scanning electron microscope (SEM) observation showed that VOCs released by ZD01 could cause more flaccid and gapped hyphae of A. solani. Also, we found that VOCs produced by ZD01 can inhibit the conidia germination and reduce the lesion areas and number of A. solani in vivo significantly. Meanwhile, based on gas chromatography/mass spectrometry (GC/MS) analysis, 29 volatile compounds produced by strain ZD01 were identified. Out of 29 identified VOCs, 9 VOCs showed complete growth inhibition activities against A. solani. Moreover, we identified two virulence-associated genes (slt2 and sod) in A. solani. slt2 is a key gene that regulates the mycelial growth, penetration, sporulation, and virulence in vivo in A. solani. In addition, sod plays a significant role in the SOD synthetic pathway in A. solani. Results from qRT-PCR showed that the transcriptional expression of these two genes was down-regulated after being treated by VOCs produced by ZD01. These results are useful for a better understanding of the biocontrol mechanism of Bacillus and offer a potential method for potato early blight disease control.
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Affiliation(s)
- Dai Zhang
- College of Plant Protection, Hebei Agricultural University, Baoding, China
| | - Shuiqing Yu
- College of Plant Protection, Hebei Agricultural University, Baoding, China
| | - Yiqing Yang
- College of Plant Protection, Hebei Agricultural University, Baoding, China
| | - Jinglin Zhang
- Beijing Laboratory for Food Quality and Safety, Beijing Technology and Business University, Beijing, China
| | - Dongmei Zhao
- College of Plant Protection, Hebei Agricultural University, Baoding, China
| | - Yang Pan
- College of Plant Protection, Hebei Agricultural University, Baoding, China
| | - Shasha Fan
- College of Plant Protection, Hebei Agricultural University, Baoding, China
| | - Zhihui Yang
- College of Plant Protection, Hebei Agricultural University, Baoding, China
| | - Jiehua Zhu
- College of Plant Protection, Hebei Agricultural University, Baoding, China
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