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Vinothini K, Nakkeeran S, Saranya N, Jothi P, Richard JI, Perveen K, Bukhari NA, Glick BR, Sayyed RZ, Mastinu A. Rhizosphere Engineering of Biocontrol Agents Enriches Soil Microbial Diversity and Effectively Controls Root-Knot Nematodes. MICROBIAL ECOLOGY 2024; 87:120. [PMID: 39340684 PMCID: PMC11438712 DOI: 10.1007/s00248-024-02435-7] [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: 06/16/2024] [Accepted: 09/14/2024] [Indexed: 09/30/2024]
Abstract
The root-knot nematode (RKN) causes significant yield loss in tomatoes. Understanding the interaction of biocontrol agents (BCAs)-nematicides-soil microbiomes and RKNs is essential for enhancing the efficacy of biocontrol agents and nematicides to curb RKN damage to crops. The present study aimed to evaluate the in vitro effectiveness of BACa and nematicide against RKN and to apply the amplicon sequencing to assess the interaction of Bacillus velezensis (VB7) and Trichoderma koningiopsis (TK) against RKNs. Metagenomic analysis revealed the relative abundance of three phyla such as Proteobacteria (42.16%), Firmicutes (19.57%), and Actinobacteria (17.69%) in tomato rhizospheres. Those tomato rhizospheres treated with the combined application of B. velezensis VB7 + T. koningiopsis TK and RKN had a greater frequency of diversity and richness than the control. RKN-infested tomato rhizosphere drenched with bacterial and fungal antagonists had the maximum diversity index of bacterial communities. A strong correlation with a maximum number of interconnection edges in the phyla Proteobacteria, Firmicutes, and Actinobacteria was evident in soils treated with both B. velezensis VB7 and T. koningiopsis TK challenged against RKN in infected soil. The present study determined a much greater diversity of bacterial taxa observed in tomato rhizosphere soils treated with B. velezensis VB7 and T. koningiopsis TK than in untreated soil. It is suggested that the increased diversity and abundance of bacterial communities might be responsible for increased nematicidal properties in tomato plants. Hence, the combined applications of B. velezensis VB7 and T. koningiopsis TK can enhance the nematicidal action to curb RKN infecting tomatoes.
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Affiliation(s)
- K Vinothini
- Department of Plant Pathology, Centre for Plant Protection Studies, Tamil Nadu Agricultural University, Coimbatore, 641 003, India
| | - S Nakkeeran
- Department of Plant Pathology, Centre for Plant Protection Studies, Tamil Nadu Agricultural University, Coimbatore, 641 003, India.
| | - N Saranya
- Department of Plant Molecular Biology and Bioinformatics, Centre for Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore, 641003, India
| | - P Jothi
- Department of Nematology, Centre for Plant Protection Studies, Tamil Nadu Agricultural University, Coimbatore, 641 003, India
| | - J Infant Richard
- Department of Plant Molecular Biology and Bioinformatics, Centre for Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore, 641003, India
| | - Kahkashan Perveen
- Department of Botany & Microbiology, College of Science, King Saud University, P.O. Box-22452, 11495, Riyadh, Saudi Arabia
| | - Najat A Bukhari
- Department of Botany & Microbiology, College of Science, King Saud University, P.O. Box-22452, 11495, Riyadh, Saudi Arabia
| | - Bernard R Glick
- Department of Biology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| | - R Z Sayyed
- Department of Biological Sciences and Chemistry, College of Arts and Science, University of Nizwa, Nizwa, 616, Sultanate of Oman.
| | - Andrea Mastinu
- Department of Molecular and Translational Medicine, Division of Pharmacology, University of Brescia, Viale Europa 11, 25123, Brescia, Italy.
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Saikia J, Thakur D. A review on endophytic bacteria of orchids: functional roles toward synthesis of bioactive metabolites for plant growth promotion and disease biocontrol. PLANTA 2024; 260:70. [PMID: 39136763 DOI: 10.1007/s00425-024-04501-3] [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: 04/30/2024] [Accepted: 08/04/2024] [Indexed: 08/29/2024]
Abstract
MAIN CONCLUSION In this review, we have discussed the untapped potential of orchid endophytic bacteria as a valuable reservoir of bioactive metabolites, offering significant contributions to plant growth promotion and disease protection in the context of sustainable agriculture. Orchidaceae is one of the broadest and most diverse flowering plant families on Earth. Although the relationship between orchids and fungi is well documented, bacterial endophytes have recently gained attention for their roles in host development, vigor, and as sources of novel bioactive compounds. These endophytes establish mutualistic relationships with orchids, influencing plant growth, mineral solubilization, nitrogen fixation, and protection from environmental stress and phytopathogens. Current research on orchid-associated bacterial endophytes is limited, presenting significant opportunities to discover new species or genetic variants that improve host fitness and stress tolerance. The potential for extracting bioactive compounds from these bacteria is considerable, and optimization strategies for their sustainable production could significantly enhance their commercial utility. This review discusses the methods used in isolating and identifying endophytic bacteria from orchids, their diversity and significance in promoting orchid growth, and the production of bioactive compounds, with an emphasis on their potential applications in sustainable agriculture and other sectors.
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Affiliation(s)
- Juri Saikia
- Microbial Biotechnology Laboratory, Life Sciences Division, Institute of Advanced Study in Science and Technology (IASST) (An Autonomous R&D Institute Under DST, Govt. of India), Garchuk, Paschim Boragaon, Guwahati, 781035, India
- Department of Biotechnology, Gauhati University, Guwahati, 781014, India
| | - Debajit Thakur
- Microbial Biotechnology Laboratory, Life Sciences Division, Institute of Advanced Study in Science and Technology (IASST) (An Autonomous R&D Institute Under DST, Govt. of India), Garchuk, Paschim Boragaon, Guwahati, 781035, India.
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Jayasinghe H, Chang HX, Knobloch S, Yang SH, Hendalage DPB, Ariyawansa KGSU, Liu PY, Stadler M, Ariyawansa HA. Metagenomic insight to apprehend the fungal communities associated with leaf blight of Welsh onion in Taiwan. FRONTIERS IN PLANT SCIENCE 2024; 15:1352997. [PMID: 38495366 PMCID: PMC10941342 DOI: 10.3389/fpls.2024.1352997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Accepted: 02/12/2024] [Indexed: 03/19/2024]
Abstract
Plants are associated with a large diversity of microbes, and these complex plant-associated microbial communities are critical for plant health. Welsh onion (Allium fistulosum L.) is one of the key and oldest vegetable crops cultivated in Taiwan. The leaf of the Welsh onion is one of the famous spices in Taiwanese cuisine, thus, it is crucial to control foliar diseases. In recent years, Welsh onion cultivation in Taiwan has been severely threatened by the occurrence of leaf blight disease, greatly affecting their yield and quality. However, the overall picture of microbiota associated with the Welsh onion plant is still not clear as most of the recent etiological investigations were heavily based on the isolation of microorganisms from diseased plants. Therefore, studying the diversity of fungal communities associated with the leaf blight symptoms of Welsh onion may provide information regarding key taxa possibly involved in the disease. Therefore, this investigation was mainly designed to understand the major fungal communities associated with leaf blight to identify key taxa potentially involved in the disease and further evaluate any shifts in both phyllosphere and rhizosphere mycobiome assembly due to foliar pathogen infection by amplicon sequencing targeting the Internal Transcribed Spacer (ITS) 1 region of the rRNA. The alpha and beta-diversity analyses were used to compare the fungal communities and significant fungal groups were recognized based on linear discriminant analyses. Based on the results of relative abundance data and co-occurrence networks in symptomatic plants we revealed that the leaf blight of Welsh onion in Sanxing, is a disease complex mainly involving Stemphylium and Colletotrichum taxa. In addition, genera such as Aspergillus, Athelia and Colletotrichum were abundantly found associated with the symptomatic rhizosphere. Alpha-diversity in some fields indicated a significant increase in species richness in the symptomatic phyllosphere compared to the asymptomatic phyllosphere. These results will broaden our knowledge of pathogens of Welsh onion associated with leaf blight symptoms and will assist in developing effective disease management strategies to control the progress of the disease.
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Affiliation(s)
- Himanshi Jayasinghe
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan
| | - Hao-Xun Chang
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan
| | - Stephen Knobloch
- Department of Food Technology, Fulda University of Applied Sciences, Fulda, Germany
| | - Shan-Hua Yang
- Institute of Fisheries Science, National Taiwan University, Taipei, Taiwan
| | - D. P. Bhagya Hendalage
- Department of Plant Sciences, Faculty of Science, University of Colombo, Colombo, Sri Lanka
| | | | - Po-Yu Liu
- School of Medicine, College of Medicine, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - Marc Stadler
- Department Microbial Drugs, Helmholtz Centre for Infection Research GmbH (HZI), Braunschweig, Germany
| | - Hiran A. Ariyawansa
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan
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Resendiz-Nava CN, Alonso-Onofre F, Silva-Rojas HV, Rebollar-Alviter A, Rivera-Pastrana DM, Stasiewicz MJ, Nava GM, Mercado-Silva EM. Tomato Plant Microbiota under Conventional and Organic Fertilization Regimes in a Soilless Culture System. Microorganisms 2023; 11:1633. [PMID: 37512805 PMCID: PMC10383152 DOI: 10.3390/microorganisms11071633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 06/15/2023] [Accepted: 06/19/2023] [Indexed: 07/30/2023] Open
Abstract
Tomato is the main vegetable cultivated under soilless culture systems (SCSs); production of organic tomato under SCSs has increased due to consumer demands for healthier and environmentally friendly vegetables. However, organic tomato production under SCSs has been associated with low crop performance and fruit quality defects. These agricultural deficiencies could be linked to alterations in tomato plant microbiota; nonetheless, this issue has not been sufficiently addressed. Thus, the main goal of the present study was to characterize the rhizosphere and phyllosphere of tomato plants cultivated under conventional and organic SCSs. To accomplish this goal, tomato plants grown in commercial greenhouses under conventional or organic SCSs were tested at 8, 26, and 44 weeks after seedling transplantation. Substrate (n = 24), root (n = 24), and fruit (n = 24) composite samples were subjected to DNA extraction and high-throughput 16S rRNA gene sequencing. The present study revealed that the tomato core microbiota was predominantly constituted by Proteobacteria, Actinobacteria, and Firmicutes. Remarkably, six bacterial families, Bacillaceae, Microbacteriaceae, Nocardioidaceae, Pseudomonadaceae, Rhodobacteraceae, and Sphingomonadaceae, were shared among all substrate, rhizosphere, and fruit samples. Importantly, it was shown that plants under organic SCSs undergo a dysbiosis characterized by significant changes in the relative abundance of Bradyrhizobiaceae, Caulobacteraceae, Chitinophagaceae, Enterobacteriaceae, Erythrobacteraceae, Flavobacteriaceae, Nocardioidaceae, Rhodobacteraceae, and Streptomycetaceae. These results suggest that microbial alterations in substrates, roots, and fruits could be potential factors in contributing to the crop performance and fruit quality deficiencies observed in organic SCSs.
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Affiliation(s)
- Carolina N Resendiz-Nava
- Facultad de Quimica, Universidad Autonoma de Queretaro, Cerro de las Campanas S/N, Queretaro 76010, Queretaro, Mexico
| | | | - Hilda V Silva-Rojas
- Posgrado en Recursos Geneticos y Productividad, Produccion de Semillas, Colegio de Postgraduados, Km 36.5 Carretera Mexico-Texcoco, Texcoco 56264, Mexico
| | - Angel Rebollar-Alviter
- Centro Regional Morelia, Universidad Autonoma de Chapingo, Morelia 58170, Michoacan, Mexico
| | - Dulce M Rivera-Pastrana
- Facultad de Quimica, Universidad Autonoma de Queretaro, Cerro de las Campanas S/N, Queretaro 76010, Queretaro, Mexico
| | - Matthew J Stasiewicz
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, 1302W Pennsylvania Ave, Urbana, IL 61801, USA
| | - Gerardo M Nava
- Facultad de Quimica, Universidad Autonoma de Queretaro, Cerro de las Campanas S/N, Queretaro 76010, Queretaro, Mexico
| | - Edmundo M Mercado-Silva
- Facultad de Quimica, Universidad Autonoma de Queretaro, Cerro de las Campanas S/N, Queretaro 76010, Queretaro, Mexico
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The Effects of Plant Health Status on the Community Structure and Metabolic Pathways of Rhizosphere Microbial Communities Associated with Solanum lycopersicum. HORTICULTURAE 2022. [DOI: 10.3390/horticulturae8050404] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Powdery mildew disease caused by Oidium neolycopersici is one of the major diseases affecting tomato production in South Africa. Interestingly, limited studies exist on how this disease affects the community structure microbial communities associated with tomato plants employing shotgun metagenomics. In this study, we assess how the health status of a tomato plant affects the diversity of the rhizosphere microbial community. We collected soil samples from the rhizosphere of healthy (HR) and diseased (DR; powdery mildew infected) tomatoes, alongside bulk soil (BR), extracted DNA, and did sequencing using shotgun metagenomics. Our results demonstrated that the rhizosphere microbiome alongside some specific functions were abundant in HR followed by DR and bulk soil (BR) in the order HR > DR > BR. We found eighteen (18) bacterial phyla abundant in HR, including Actinobacteria, Acidobacteria, Aquificae, Bacteroidetes, etc. The dominant fungal phyla include; Ascomycota and Basidiomycota, while the prominent archaeal phyla are Thaumarchaeota, Crenarchaeota, and Euryarchaeota. Three (3) bacteria phyla dominated the DR samples; Bacteroidetes, Gemmatimonadetes, and Thermotoga. Our result also employed the SEED subsystem and revealed that the metabolic pathways involved were abundant in HR. The α-diversity demonstrates that there is no significant difference among the rhizosphere microbiomes across the sites, while β-diversity demonstrated a significant difference.
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Saikia J, Mazumdar R, Thakur D. Phylogenetic affiliation of endophytic actinobacteria associated with selected orchid species and their role in growth promotion and suppression of phytopathogens. FRONTIERS IN PLANT SCIENCE 2022; 13:1058867. [PMID: 36570961 PMCID: PMC9769409 DOI: 10.3389/fpls.2022.1058867] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 11/03/2022] [Indexed: 05/22/2023]
Abstract
Endophytic actinobacteria aid in plant development and disease resistance by boosting nutrient uptake or producing secondary metabolites. For the first time, we investigated the culturable endophytic actinobacteria associated with ten epiphytic orchid species of Assam, India. 51 morphologically distinct actinobacteria were recovered from surface sterilized roots and leaves of orchids and characterized based on different PGP and antifungal traits. According to the 16S rRNA gene sequence, these isolates were divided into six families and eight genera, where Streptomyces was most abundant (n=29, 56.86%), followed by Actinomadura, Nocardia, Nocardiopsis, Nocardioides, Pseudonocardia, Microbacterium, and Mycolicibacterium. Regarding PGP characteristics, 25 (49.01%) isolates demonstrated phosphate solubilization in the range of 61.1±4.4 - 289.7±11.9 µg/ml, whereas 27 (52.94%) isolates biosynthesized IAA in the range of 4.0 ± 0.08 - 43.8 ± 0.2 µg/ml, and 35 (68.62%) isolates generated ammonia in the range of 0.9 ± 0.1 - 5.9 ± 0.2 µmol/ml. These isolates also produced extracellular enzymes, viz. protease (43.13%), cellulase (23.52%), pectinase (21.56%), ACC deaminase (27.45%), and chitinase (37.25%). Out of 51 isolates, 27 (52.94%) showed antagonism against at least one test phytopathogen. In molecular screening, most isolates with antifungal and chitinase producing traits revealed the presence of 18 family chitinase genes. Two actinobacterial endophytes, Streptomyces sp. VCLA3 and Streptomyces sp. RVRA7 were ranked as the best strains based on PGP and antifungal activity on bonitur scale. GC-MS examination of ethyl acetate extract of these potent strains displayed antimicrobial compound phenol, 2,4-bis-(1,1-dimethylethyl) as the major metabolite along with other antifungal and plant growth beneficial bioactive chemicals. SEM analysis of fungal pathogen F. oxysporum (MTCC 4633) affected by Streptomyces sp. VCLA3 revealed significant destruction in the spore structure. An in vivo plant growth promotion experiment with VCLA3 and RVRA7 on chili plants exhibited statistically significant (p<0.05) improvements in all of the evaluated vegetative parameters compared to the control. Our research thus gives insight into the diversity, composition, and functional significance of endophytic actinobacteria associated with orchids. This research demonstrates that isolates with multiple plant development and broad-spectrum antifungal properties are beneficial for plant growth. They may provide a viable alternative to chemical fertilizers and pesticides and a sustainable solution for chemical inputs in agriculture.
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Affiliation(s)
- Juri Saikia
- Microbial Biotechnology Laboratory, Life Sciences Division, Institute of Advanced Study in Science and Technology (IASST), Guwahati, India
- Department of Biotechnology, Gauhati University, Guwahati, India
| | - Rajkumari Mazumdar
- Microbial Biotechnology Laboratory, Life Sciences Division, Institute of Advanced Study in Science and Technology (IASST), Guwahati, India
- Department of Molecular Biology & Biotechnology, Cotton University, Guwahati, India
| | - Debajit Thakur
- Microbial Biotechnology Laboratory, Life Sciences Division, Institute of Advanced Study in Science and Technology (IASST), Guwahati, India
- *Correspondence: Debajit Thakur,
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Sui Y, Zhao Q, Wang Z, Liu J, Jiang M, Yue J, Lan J, Liu J, Liao Q, Wang Q, Yang Q, Zhang H. A Comparative Analysis of the Microbiome of Kiwifruit at Harvest Under Open-Field and Rain-Shelter Cultivation Systems. Front Microbiol 2021; 12:757719. [PMID: 34659192 PMCID: PMC8515128 DOI: 10.3389/fmicb.2021.757719] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 09/07/2021] [Indexed: 11/17/2022] Open
Abstract
The composition of microbial communities can directly affect fruit quality, health status, and storability. The present study characterized the epiphytes and endophytes of “Hongyang” and “Cuiyu” kiwifruit at harvest under grown under open-field (OF) and rain-shelter (RS) cultivation systems. Disease incidence in kiwifruit was significantly lower (p < 0.05) under the RS system than it was under the OF system. High-throughput sequencing [16S V3-V4 ribosomal region and the fungal internal transcribed spacer (ITS2)] was conducted to compare the composition of the epiphytic and endophytic microbial community of kiwifruit under the two cultivation systems. Results indicated that the abundance of Actinobacteria, Bacteroidetes, Enterobacteriales, Acetobacterales, Sphingomonas, Pseudomonas, and Sphingobacterium was higher under the RS system, relative to the OF system, while the abundance of Capnodiales, Hypocreales, Vishniacozyma, and Plectosphaerella was also higher under the RS system. Some of these bacterial and fungal taxa have been reported to as act as biocontrol agents and reduce disease incidence. Notably, the α-diversity of the epiphytic bacterial and fungal communities on kiwifruit was higher under RS cultivation. In summary, RS cultivation reduced natural disease incidence in kiwifruit, which may be partially attributed to differences in the structure and composition of the microbial community present in and on kiwifruit.
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Affiliation(s)
- Yuan Sui
- Chongqing Key Laboratory of Economic Plant Biotechnology, College of Landscape Architecture and Life Science/Institute of Special Plants, Chongqing University of Arts and Sciences, Yongchuan, Chongqing, China
| | - Qianhua Zhao
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
| | - Zhenshuo Wang
- Department of Plant Pathology, MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China.,Engineering Research Center of Plant Growth Regulators/Crop Chemical Control Research Center, Department of Agronomy, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Jia Liu
- Chongqing Key Laboratory of Economic Plant Biotechnology, College of Landscape Architecture and Life Science/Institute of Special Plants, Chongqing University of Arts and Sciences, Yongchuan, Chongqing, China
| | - Mingguo Jiang
- Guangxi Key Laboratory for Polysaccharide Materials and Modifications, School of Marine Sciences and Biotechnology, Guangxi University for Nationalities, Nanning, China
| | - Junyang Yue
- College of Horticulture, Anhui Agricultural University, Hefei, China
| | - Jianbin Lan
- Chongqing Key Laboratory of Economic Plant Biotechnology, College of Landscape Architecture and Life Science/Institute of Special Plants, Chongqing University of Arts and Sciences, Yongchuan, Chongqing, China
| | - Jing Liu
- Chongqing Key Laboratory of Economic Plant Biotechnology, College of Landscape Architecture and Life Science/Institute of Special Plants, Chongqing University of Arts and Sciences, Yongchuan, Chongqing, China
| | - Qinhong Liao
- Chongqing Key Laboratory of Economic Plant Biotechnology, College of Landscape Architecture and Life Science/Institute of Special Plants, Chongqing University of Arts and Sciences, Yongchuan, Chongqing, China
| | - Qi Wang
- Department of Plant Pathology, MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China
| | - Qiya Yang
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
| | - Hongyin Zhang
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
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Volatile organic compounds profile synthesized and released by endophytes of tomato (Solanum lycopersici L.) and their antagonistic role. Arch Microbiol 2021; 203:1383-1397. [PMID: 33386869 DOI: 10.1007/s00203-020-02136-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 11/12/2020] [Accepted: 11/19/2020] [Indexed: 12/15/2022]
Abstract
The endophytic microbiome uses mechanisms such as the secretion of diffusible antibiotic molecules, synthesis and release of volatile organic compounds, and/or toxins to protect plants. The aim of this research was to study the volatile organic compounds (VOCs) profile as well as the diffusible secondary metabolites produced and released by endophytic bacteria isolated from tomato plants that in in-vitro assays prevented growth of pathogenic fungi. Bacteria belonging to seven genera (Acinetobacter, Arthrobacter, Bacillus, Microbacterium, Pantoea, Pseudomonas, and Stenotrophomonas) were isolated from different tissues of tomato plants with and without symptoms of Gray leaf spot, a disease provoked by Stemphylium lycopersici. In vitro, antagonistic assays were performed and the effect of volatile and soluble compounds released by endophytic bacteria on the growth of pathogenic fungi was determined. The VOCs synthesized by the endophytes were extracted, identified and quantified. These isolates representatives of seven bacterial genera inhibited the growth of three fungal pathogens of tomato S. lycopersici, Alternaria alternata and Corynespora cassiicola, which was related to the synthesis of soluble compounds as well as VOCs. Endophytes synthesize and release different VOCs, probably due to the different type of interaction that each bacterium establishes with the fungus, presenting a range of fungal growth inhibition.
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