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Zhang Z, Sui L, Tian Y, Lu Y, Xia X, Liu W, Cheng K, Li Q, Shi W. Metarhizium rileyi with broad-spectrum insecticidal ability confers resistance against phytopathogens and insect pests as a phytoendophyte. PEST MANAGEMENT SCIENCE 2024; 80:3246-3257. [PMID: 38358040 DOI: 10.1002/ps.8027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 01/19/2024] [Accepted: 02/15/2024] [Indexed: 02/16/2024]
Abstract
BACKGROUND Entomophagous fungi (EPF) not only directly kill insect pests, but also colonize plants and improve their resistance against pests. However, most previous research has focused on Beauveria bassiana and Metarhizium anisopliae, and there are few reports on whether other EPF can enhance resistance against pests via endogenous colonization. Herein, an EPF strain was isolated from diseased larvae of Spodoptera litura in a soybean field, and subjected to genome-wide sequencing at the chromosomal level. The pathogenicity of the isolate toward various pest insects was evaluated, and the ability to colonize plants and induce resistance against phytopathogens and insect pests was tested. RESULTS The purified isolate was identified as M. rileyi and designated MrS1Gz1-1. Biological assays revealed its strong pathogenicity toward five insect pests belonging to Lepidoptera and Hemiptera. Furthermore, the strain inhibited the growth of soil-borne plant disease caused by Sclerotinia sclerotiorum in vitro. It colonized plants as an endophyte via soil application, thereby inducing plant resistance-related genes against phytopathogen infection, and it disrupted the feeding selectivity of S. litura larvae. CONCLUSION M. rileyi MrS1Gz1-1 has potential as a broad-spectrum microbial control agent that can induce resistance against phytopathogens and insect pests feeding as an endotype. The complete genome provides a valuable resource for exploring host interactions. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Zhengkun Zhang
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Jilin Key Laboratory of Agricultural Microbiology, Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Areas, Changchun, China
| | - Li Sui
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Jilin Key Laboratory of Agricultural Microbiology, Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Areas, Changchun, China
| | - Yifan Tian
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Jilin Key Laboratory of Agricultural Microbiology, Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Areas, Changchun, China
- Department of Entomology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Yang Lu
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Jilin Key Laboratory of Agricultural Microbiology, Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Areas, Changchun, China
| | - Xinyao Xia
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Wende Liu
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Ke Cheng
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Jilin Key Laboratory of Agricultural Microbiology, Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Areas, Changchun, China
| | - Qiyun Li
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Jilin Key Laboratory of Agricultural Microbiology, Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Areas, Changchun, China
- Department of Entomology, College of Plant Protection, China Agricultural University, Beijing, China
- Jilin Agricultural Science and Technology University, Jilin, P. R. China
| | - Wangpeng Shi
- Department of Entomology, College of Plant Protection, China Agricultural University, Beijing, China
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Zhang BX, Liu FF, Liu F, Qi WX, Si YQ, Ren HY, Rao XJ. SfMBP: A novel microbial binding protein and pattern recognition receptor in the fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae). DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2024; 154:105142. [PMID: 38309673 DOI: 10.1016/j.dci.2024.105142] [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: 12/19/2023] [Revised: 01/26/2024] [Accepted: 02/01/2024] [Indexed: 02/05/2024]
Abstract
The fall armyworm, Spodoptera frugiperda, poses a significant threat as a highly destructive agricultural pest in many countries. Understanding the complex interplay between the insect immune system and entomopathogens is critical for optimizing biopesticide efficacy. In this study, we identified a novel microbial binding protein, SfMBP, in S. frugiperda. However, the specific role of SfMBP in the immune response of S. frugiperda remains elusive. Encoded by the LOC118269163 gene, SfMBP shows significant induction in S. frugiperda larvae infected with the entomopathogen Beauveria bassiana. Consisting of 115 amino acids with a signal peptide, an N-terminal flexible region and a C-terminal β-sheet, SfMBP lacks any known functional domains. It is expressed predominantly during early larval stages and in the larval epidermis. Notably, SfMBP is significantly induced in larvae infected with bacteria and fungi and in SF9 cells stimulated by peptidoglycan. While recombinant SfMBP (rSfMBP) does not inhibit bacterial growth, it demonstrates binding capabilities to bacteria, fungal spores, peptidoglycan, lipopolysaccharides, and polysaccharides. This binding is inhibited by monosaccharides and EDTA. Molecular docking reveals potential Zn2+-interacting residues and three cavities. Furthermore, rSfMBP induces bacterial agglutination in the presence of Zn2+. It also binds to insect hemocytes and SF9 cells, enhancing phagocytosis and agglutination responses. Injection of rSfMBP increased the survival of S. frugiperda larvae infected with B. bassiana, whereas blocking SfMBP with the antibody decreased survival. These results suggest that SfMBP acts as a pattern recognition receptor that enhances pathogen recognition and cellular immune responses. Consequently, this study provides valuable insights for the development of pest control measures.
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Affiliation(s)
- Bang-Xian Zhang
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, School of Plant Protection, Anhui Agricultural University, Hefei, 230036, China; Key Laboratory of Agri-products Quality and Biosafety (Anhui Agricultural University), Ministry of Education, China; School of Biological Science and Food Engineering, Chuzhou, 239000, China
| | - Fang-Fang Liu
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, School of Plant Protection, Anhui Agricultural University, Hefei, 230036, China; Key Laboratory of Agri-products Quality and Biosafety (Anhui Agricultural University), Ministry of Education, China
| | - Feng Liu
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, School of Plant Protection, Anhui Agricultural University, Hefei, 230036, China; Key Laboratory of Agri-products Quality and Biosafety (Anhui Agricultural University), Ministry of Education, China
| | - Wen-Xuan Qi
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, School of Plant Protection, Anhui Agricultural University, Hefei, 230036, China; Key Laboratory of Agri-products Quality and Biosafety (Anhui Agricultural University), Ministry of Education, China
| | - Yan-Qin Si
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, School of Plant Protection, Anhui Agricultural University, Hefei, 230036, China; Key Laboratory of Agri-products Quality and Biosafety (Anhui Agricultural University), Ministry of Education, China
| | - Hai-Yan Ren
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, School of Plant Protection, Anhui Agricultural University, Hefei, 230036, China; Key Laboratory of Agri-products Quality and Biosafety (Anhui Agricultural University), Ministry of Education, China
| | - Xiang-Jun Rao
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, School of Plant Protection, Anhui Agricultural University, Hefei, 230036, China; Key Laboratory of Agri-products Quality and Biosafety (Anhui Agricultural University), Ministry of Education, China.
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Zhang Z, Tian Y, Sui L, Lu Y, Cheng K, Zhao Y, Li Q, Shi W. First record of Aspergillus nomiae as a broad-spectrum entomopathogenic fungus that provides resistance against phytopathogens and insect pests by colonization of plants. Front Microbiol 2024; 14:1284276. [PMID: 38260878 PMCID: PMC10801167 DOI: 10.3389/fmicb.2023.1284276] [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: 08/28/2023] [Accepted: 12/13/2023] [Indexed: 01/24/2024] Open
Abstract
Introduction Aspergillus nomiae is known as a pathogenic fungus that infects humans and plants but has never been reported as an entomophagous fungus (EPF) that can provide other functions as an endotype. Methods A strain of EPF was isolated and identified from diseased larvae of Spodoptera litura in a soybean field and designated AnS1Gzl-1. Pathogenicity of the strain toward various insect pests was evaluated, especially the ability to colonize plants and induce resistance against phytopathogens and insect pests. Results The isolated EPF strain AnS1Gzl-1 was identified as A. nomiae; it showed strong pathogenicity toward five insect pests belonging to Lepidoptera and Hemiptera. Furthermore, the strain inhibited the growth of Sclerotinia sclerotiorum in vitro, a causal agent of soil-borne plant disease. It colonized plants as an endophyte via root irrigation with a high colonization rate of 90%, thereby inducing plant resistance against phytopathogen infection, and disrupting the feeding selectivity of S. litura larvae. Discussion This is the first record of a natural infection of A. nomiae on insects. A. nomiae has the potential to be used as a dual biocontrol EPF because of its ability to not only kill a broad spectrum of insect pests directly but also induce resistance against phytopathogens via plant colonization.
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Affiliation(s)
- Zhengkun Zhang
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Changchun, China
- Jilin Key Laboratory of Agricultural Microbiology, Changchun, China
- Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Areas, Changchun, China
| | - Yifan Tian
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Changchun, China
- Jilin Key Laboratory of Agricultural Microbiology, Changchun, China
- Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Areas, Changchun, China
- Department of Entomology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Li Sui
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Changchun, China
- Jilin Key Laboratory of Agricultural Microbiology, Changchun, China
- Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Areas, Changchun, China
| | - Yang Lu
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Changchun, China
- Jilin Key Laboratory of Agricultural Microbiology, Changchun, China
- Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Areas, Changchun, China
| | - Ke Cheng
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Changchun, China
- Jilin Key Laboratory of Agricultural Microbiology, Changchun, China
- Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Areas, Changchun, China
| | - Yu Zhao
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Changchun, China
- Jilin Key Laboratory of Agricultural Microbiology, Changchun, China
- Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Areas, Changchun, China
| | - Qiyun Li
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Changchun, China
- Jilin Key Laboratory of Agricultural Microbiology, Changchun, China
- Key Laboratory of Integrated Pest Management on Crops in Northeast China, Ministry of Agriculture and Rural Areas, Changchun, China
- Department of Entomology, College of Plant Protection, China Agricultural University, Beijing, China
- Jilin Agricultural Science and Technology University, Jilin, China
| | - Wangpeng Shi
- Department of Entomology, College of Plant Protection, China Agricultural University, Beijing, China
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Fang M, Long W, Sun J, Wang A, Chen L, Cui Y, Huang Z, Li J, Ruan W, Rasmann S, Wei X. Toxicity of fungal-derived volatile organic compounds against root-knot nematodes. PEST MANAGEMENT SCIENCE 2023; 79:5162-5172. [PMID: 37574969 DOI: 10.1002/ps.7719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 08/09/2023] [Accepted: 08/14/2023] [Indexed: 08/15/2023]
Abstract
BACKGROUND Root-knot nematodes (RKNs), including Meloidogyne species, are among the most destructive plant-parasites worldwide. Recent evidence suggests that entomopathogenic fungi (EPF) can antagonize RKNs. Such antagonistic effects are likely mediated by toxic metabolites, including volatile organic compounds (VOCs), produced by the fungi. However, how widespread these effects are across EPF species, and which VOCs mediate negative interactions between EPF and RKNs needs to be further elucidated. RESULTS First, we evaluated the nematicidal effect of VOCs emitted by 46 EPF isolates against Meloidogyne incognita and found variable toxicity depending on the isolate. Second, we measured the nematicidal effect of highly toxic isolates, including species in the genus Talaromyces, Aspergillus, Clonostachys, and Purpureocillium and, third, we analyzed the nematicidal effect of major VOCs, including 2-methyl-1-propanol, 3-methyl-1-butanol, isopropyl alcohol and 2-methyl-3-pentanone. The mortality of M. incognita juveniles (J2s) was generally high (50%) either via airborne or in-solution contact with VOCs. Moreover, the tested VOCs significantly inhibited egg hatching, and repelled J2s away from the VOCs. CONCLUSION This study not only provides insights into the ecological function of VOCs in the rhizosphere, but also provides new approaches for developing environmentally friendly control methods of RKNs in agroecosystems. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Ming Fang
- College of Life Sciences, Nankai University, Tianjin, China
| | - Wenxin Long
- School of Mathematical Sciences and LPMC, Nankai University, Tianjin, China
| | - Jie Sun
- College of Life Sciences, Nankai University, Tianjin, China
| | - Ailing Wang
- College of Life Sciences, Nankai University, Tianjin, China
| | - Lei Chen
- College of Life Sciences, Nankai University, Tianjin, China
| | | | | | | | - Weibin Ruan
- College of Life Sciences, Nankai University, Tianjin, China
| | - Sergio Rasmann
- Laboratory of Functional Ecology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
| | - Xianqin Wei
- College of Life Sciences, Nankai University, Tianjin, China
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Zhang BX, Liu FF, Liu F, Sun YX, Rao XJ. Dual RNA Sequencing of Beauveria bassiana-Infected Spodoptera frugiperda Reveals a Fungal Protease with Entomopathogenic and Antiphytopathogenic Activities. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:12757-12774. [PMID: 37602431 DOI: 10.1021/acs.jafc.3c02356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/22/2023]
Abstract
Insect pests and phytopathogens significantly impact crop yield and quality. The fall armyworm (FAW) Spodoptera frugiperda and the phytopathogen Fusarium graminearum cause substantial economic losses in crops like barley and wheat. However, the entomopathogen Beauveria bassiana shows limited efficacy against FAW, and its antiphytopathogenic activities against F. graminearum remain unclear. Here, dual RNA sequencing was performed to identify differentially expressed genes in B. bassiana-infected FAW larvae. We found that the BbAorsin gene was significantly upregulated at 36 and 48 h post-infection. BbAorsin encodes a serine-carboxyl protease and is mainly expressed in blastospores and hyphae. Overexpression of BbAorsin in B. bassiana ARSEF2860 enhanced virulence against Galleria mellonella and FAW larvae and inhibited F. graminearum growth. The recombinant BbAorsin protein induced apoptosis and necrosis in FAW hemocytes and inhibited F. graminearum spore germination. These findings shed light on transcriptomic mechanisms governing insect-pathogen interactions, which could aid in developing dual-functional entomopathogens and anti-phytopathogens.
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Affiliation(s)
- Bang-Xian Zhang
- Key Laboratory of Biology and Sustainable Management of Plant Diseases and Pests of Anhui Higher Education Institutes, School of Plant Protection, Anhui Agricultural University, Hefei 230036, China
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, Hefei 230036, China
- Department of Scientific Research, Chuzhou University, Chuzhou 239000, China
| | - Fang-Fang Liu
- Key Laboratory of Biology and Sustainable Management of Plant Diseases and Pests of Anhui Higher Education Institutes, School of Plant Protection, Anhui Agricultural University, Hefei 230036, China
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, Hefei 230036, China
| | - Feng Liu
- Key Laboratory of Biology and Sustainable Management of Plant Diseases and Pests of Anhui Higher Education Institutes, School of Plant Protection, Anhui Agricultural University, Hefei 230036, China
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, Hefei 230036, China
| | - Yan-Xia Sun
- Key Laboratory of Biology and Sustainable Management of Plant Diseases and Pests of Anhui Higher Education Institutes, School of Plant Protection, Anhui Agricultural University, Hefei 230036, China
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, Hefei 230036, China
| | - Xiang-Jun Rao
- Key Laboratory of Biology and Sustainable Management of Plant Diseases and Pests of Anhui Higher Education Institutes, School of Plant Protection, Anhui Agricultural University, Hefei 230036, China
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, Hefei 230036, China
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Sun YX, Zhang BX, Zhang WT, Wang Q, Toufeeq S, Rao XJ. UV-induced mutagenesis of Beauveria bassiana (Hypocreales: Clavicipitaceae) yields two hypervirulent isolates with different transcriptomic profiles. PEST MANAGEMENT SCIENCE 2023. [PMID: 36914429 DOI: 10.1002/ps.7452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 01/31/2023] [Accepted: 03/14/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND The fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae) can infest over 300 plant species and cause huge economic losses. Beauveria bassiana (Hypocreales: Clavicipitaceae) is one of the most widely used entomopathogenic fungi (EPF). Unfortunately, the efficacy of B. bassiana against S. frugiperda is quite low. Hypervirulent EPF isolates can be obtained by ultraviolet (UV)-irradiation. Here we report on the UV-induced mutagenesis and transcriptomic analysis of B. bassiana. RESULTS The wild-type (WT) B. bassiana (ARSEF2860) was exposed to UV light to induce mutagenesis. Two mutants (named 6M and 8M) showed higher growth rates, conidial yields, and germination rates compared to the WT strain. The mutants showed higher levels of tolerance to osmotic, oxidative, and UV stresses. The mutants showed higher protease, chitinase, cellulose, and chitinase activities than WT. Both WT and mutants were compatible with the insecticides matrine, spinetoram, and chlorantraniliprole, but incompatible with emamectin benzoate. Insect bioassays showed that both mutants were more virulent against S. frugiperda and the greater wax moth Galleria mellonella. Transcriptomic profiles of the WT and mutants were determined by RNA-sequencing. The differentially expressed genes (DEGs) were identified. The gene set enrichment analysis (GSEA), protein-protein interaction (PPI) network, and hub gene analysis revealed virulence-related genes. CONCLUSION Our data demonstrate that UV-irradiation is a very efficient and economical technique to improve the virulence and stress resistance of B. bassiana. Comparative transcriptomic profiles of the mutants provide insights into virulence genes. These results provide new ideas for improving the genetic engineering and field efficacy of EPF. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Yan-Xia Sun
- Key Laboratory of Biology and Sustainable Management of Plant Diseases and Pests of Anhui Higher Education Institutes, School of Plant Protection, Anhui Agricultural University, Hefei, China
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, Hefei, China
| | - Bang-Xian Zhang
- Key Laboratory of Biology and Sustainable Management of Plant Diseases and Pests of Anhui Higher Education Institutes, School of Plant Protection, Anhui Agricultural University, Hefei, China
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, Hefei, China
- Department of Science and Technology, Chuzhou University, Chuzhou, China
| | - Wen-Ting Zhang
- Key Laboratory of Biology and Sustainable Management of Plant Diseases and Pests of Anhui Higher Education Institutes, School of Plant Protection, Anhui Agricultural University, Hefei, China
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, Hefei, China
| | - Qian Wang
- Key Laboratory of Biology and Sustainable Management of Plant Diseases and Pests of Anhui Higher Education Institutes, School of Plant Protection, Anhui Agricultural University, Hefei, China
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, Hefei, China
| | - Shahzad Toufeeq
- Key Laboratory of Insect Development and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Xiang-Jun Rao
- Key Laboratory of Biology and Sustainable Management of Plant Diseases and Pests of Anhui Higher Education Institutes, School of Plant Protection, Anhui Agricultural University, Hefei, China
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, Hefei, China
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Wu S, Wu J, Wang Y, Qu Y, He Y, Wang J, Cheng J, Zhang L, Cheng C. Discovery of entomopathogenic fungi across geographical regions in southern China on pine sawyer beetle Monochamus alternatus and implication for multi-pathogen vectoring potential of this beetle. FRONTIERS IN PLANT SCIENCE 2022; 13:1061520. [PMID: 36643293 PMCID: PMC9832029 DOI: 10.3389/fpls.2022.1061520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
Entomopathogen-based biocontrol is crucial for blocking the transmission of vector-borne diseases; however, few cross-latitudinal investigations of entomopathogens have been reported for vectors transmitting woody plant diseases in forest ecosystems. The pine sawyer beetle Monochamus alternatus is an important wood borer and a major vector transmitting pine wilt disease, facilitating invasion of the pinewood nematode Bursaphelenchus xylophilus (PWN) in China. Due to the limited geographical breadth of sampling regions, species diversity of fungal associates (especially entomopathogenic fungi) on M. alternatus adults and their potential ecological functions have been markedly underestimated. In this study, through traditional fungal isolation with morphological and molecular identification, 640 fungal strains (affiliated with 15 genera and 39 species) were isolated from 81 beetle cadavers covered by mycelia or those symptomatically alive across five regional populations of this pest in southern China. Multivariate analyses revealed significant differences in the fungal community composition among geographical populations of M. alternatus, presenting regionalized characteristics, whereas no significant differences were found in fungal composition between beetle genders or among body positions. Four region-representative fungi, namely, Lecanicillium attenuatum (Zhejiang), Aspergillus austwickii (Sichuan), Scopulariopsis alboflavescens (Fujian), and A. ruber (Guangxi), as well as the three fungal species Beauveria bassiana, Penicillium citrinum, and Trichoderma dorotheae, showed significantly stronger entomopathogenic activities than other fungi. Additionally, insect-parasitic entomopathogenic fungi (A. austwickii, B. bassiana, L. attenuatum, and S. alboflavescens) exhibited less to no obvious phytopathogenic activities on the host pine Pinus massoniana, whereas P. citrinum, Purpureocillium lilacinum, and certain species of Fusarium spp.-isolated from M. alternatus body surfaces-exhibited remarkably higher phytopathogenicity. Our results provide a broader view of the entomopathogenic fungal community on the vector beetle M. alternatus, some of which are reported for the first time on Monochamus spp. in China. Moreover, this beetle might be more highly-risk in pine forests than previously considered, as a potential multi-pathogen vector of both PWN and phytopathogenic fungi.
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Affiliation(s)
- Shengxin Wu
- School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, Zhejiang, China
- Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, Huzhou University, Huzhou, Zhejiang, China
| | - Jia Wu
- Station of Forest Pest Control, Anji Forestry Bureau, Huzhou, Zhejiang, China
| | - Yun Wang
- Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, Huzhou University, Huzhou, Zhejiang, China
| | - Yifei Qu
- School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, Zhejiang, China
- Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, Huzhou University, Huzhou, Zhejiang, China
| | - Yao He
- Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, Huzhou University, Huzhou, Zhejiang, China
| | - Jingyan Wang
- Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, Huzhou University, Huzhou, Zhejiang, China
| | - Jianhui Cheng
- Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, Huzhou University, Huzhou, Zhejiang, China
| | - Liqin Zhang
- School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, Zhejiang, China
- Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, Huzhou University, Huzhou, Zhejiang, China
| | - Chihang Cheng
- Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, Huzhou University, Huzhou, Zhejiang, China
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