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Sobieraj K, Derkacz D, Krasowska A, Białowiec A. Isolation and identification of carbon monoxide producing microorganisms from compost. WASTE MANAGEMENT (NEW YORK, N.Y.) 2024; 182:250-258. [PMID: 38677142 DOI: 10.1016/j.wasman.2024.04.044] [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: 01/07/2024] [Revised: 04/15/2024] [Accepted: 04/24/2024] [Indexed: 04/29/2024]
Abstract
Carbon monoxide (CO) formation has been observed during composting of various fractions of organic waste. It was reported that this production can be biotic, associated with the activity of microorganisms. However, there are no sources considering the microbial communities producing CO production in compost. This preliminary research aimed to isolate and identify microorganisms potentially responsible for the CO production in compost collected from two areas of the biowaste pile: with low (118 ppm) and high CO concentration (785 ppm). Study proved that all isolates were bacterial strains with the majority of rod-shaped Gram-positive bacteria. Both places can be inhabited by the same bacterial strains, e.g. Bacillus licheniformis and Paenibacillus lactis. The most common were Bacillus (B. licheniformis, B. haynesii, B. paralicheniformis, and B. thermolactis). After incubation of isolates in sealed bioreactors for 4 days, the highest CO levels in the headspace were recorded for B. paralicheniformis (>1000 ppm), B. licheniformis (>800 ppm), and G. thermodenitrificans (∼600 ppm). High CO concentrations were accompanied by low O2 (<6%) and high CO2 levels (>8%). It is recommended to analyze the expression of the gene encoding CODH to confirm or exclude the ability of the identified strains to convert CO2 to CO.
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Affiliation(s)
- Karolina Sobieraj
- Wrocław University of Environmental and Life Sciences, Department of Applied Bioeconomy, 37a Chełmońskiego Str., 51-630 Wrocław, Poland.
| | - Daria Derkacz
- University of Wrocław, Faculty of Biotechnology, Department of Biotransformation, F. Joliot-Curie 14a Street, 50-383 Wroclaw, Poland.
| | - Anna Krasowska
- University of Wrocław, Faculty of Biotechnology, Department of Biotransformation, F. Joliot-Curie 14a Street, 50-383 Wroclaw, Poland.
| | - Andrzej Białowiec
- Wrocław University of Environmental and Life Sciences, Department of Applied Bioeconomy, 37a Chełmońskiego Str., 51-630 Wrocław, Poland; Iowa State University, Department of Agricultural and Biosystems Engineering, 605 Bissell Road, Ames, IA 50011, USA.
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2
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Barone GD, Zhou Y, Wang H, Xu S, Ma Z, Cernava T, Chen Y. Implications of bacteria‒bacteria interactions within the plant microbiota for plant health and productivity. J Zhejiang Univ Sci B 2024:1-16. [PMID: 38773879 DOI: 10.1631/jzus.b2300914] [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: 12/14/2023] [Accepted: 02/26/2024] [Indexed: 05/24/2024]
Abstract
Crop production currently relies on the widespread use of agrochemicals to ensure food security. This practice is considered unsustainable, yet has no viable alternative at present. The plant microbiota can fulfil various functions for its host, some of which could be the basis for developing sustainable protection and fertilization strategies for plants without relying on chemicals. To harness such functions, a detailed understanding of plant‒microbe and microbe‒microbe interactions is necessary. Among interactions within the plant microbiota, those between bacteria are the most common ones; they are not only of ecological importance but also essential for maintaining the health and productivity of the host plants. This review focuses on recent literature in this field and highlights various consequences of bacteria‒bacteria interactions under different agricultural settings. In addition, the molecular and genetic backgrounds of bacteria that facilitate such interactions are emphasized. Representative examples of commonly found bacterial metabolites with bioactive properties, as well as their modes of action, are given. Integrating our understanding of various binary interactions into complex models that encompass the entire microbiota will benefit future developments in agriculture and beyond, which could be further facilitated by artificial intelligence-based technologies.
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Affiliation(s)
| | - Yaqi Zhou
- State Key Laboratory of Rice Biology and Breeding; Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects; Zhejiang Provincial Key Laboratory of Biology of Crop Pathogens and Insects; Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Hongkai Wang
- State Key Laboratory of Rice Biology and Breeding; Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects; Zhejiang Provincial Key Laboratory of Biology of Crop Pathogens and Insects; Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Sunde Xu
- State Key Laboratory of Rice Biology and Breeding; Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects; Zhejiang Provincial Key Laboratory of Biology of Crop Pathogens and Insects; Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Zhonghua Ma
- State Key Laboratory of Rice Biology and Breeding; Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects; Zhejiang Provincial Key Laboratory of Biology of Crop Pathogens and Insects; Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Tomislav Cernava
- School of Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, SO17 1BJ Southampton, UK.
| | - Yun Chen
- State Key Laboratory of Rice Biology and Breeding; Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects; Zhejiang Provincial Key Laboratory of Biology of Crop Pathogens and Insects; Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China.
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3
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Wang C, Pei J, Li H, Zhu X, Zhang Y, Wang Y, Li W, Wang Z, Liu K, Du B, Jiang J, Zhao D. Mechanisms on salt tolerant of Paenibacillus polymyxa SC2 and its growth-promoting effects on maize seedlings under saline conditions. Microbiol Res 2024; 282:127639. [PMID: 38354626 DOI: 10.1016/j.micres.2024.127639] [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] [Received: 12/05/2023] [Revised: 02/05/2024] [Accepted: 02/05/2024] [Indexed: 02/16/2024]
Abstract
Soil salinity negatively affects microbial communities, soil fertility, and agricultural productivity and has become a major agricultural problem worldwide. Plant growth-promoting rhizobacteria (PGPR) with salt tolerance can benefit plant growth under saline conditions and diminish the negative effects of salt stress on plants. In this study, we aimed to understand the salt-tolerance mechanism of Paenibacillus polymyxa at the genetic and metabolic levels and elucidate the mechanism of strain SC2 in promoting maize growth under saline conditions. Under salt stress, we found that strain SC2 promoted maize seedling growth, which was accompanied by a significant upregulation of genes encoding for the biosynthesis of peptidoglycan, polysaccharide, and fatty acid, the metabolism of purine and pyrimidine, and the transport of osmoprotectants such as trehalose, glycine betaine, and K+ in strain SC2. To further enhance the salt resistance of strain SC2, three mutants (SC2-11, SC2-13, and SC2-14) with higher capacities for salt resistance and exopolysaccharide synthesis were obtained via atmospheric and room-temperature plasma mutagenesis. In saline-alkaline soil, the mutants showed better promoting effect on maize seedlings than wild-type SC2. The fresh weight of maize seedlings was increased by 68.10% after treatment with SC2-11 compared with that of the control group. The transcriptome analysis of maize roots demonstrated that SC2 and SC2-11 could induce the upregulation of genes related to the plant hormone signal transduction, starch and sucrose metabolism, reactive oxygen species scavenging, and auxin and ethylene signaling under saline-alkaline stress. In addition, various transcription factors, such as zinc finger proteins, ethylene-responsive-element-binding protein, WRKY, myeloblastosis proteins, basic helix-loop-helix proteins, and NAC proteins, were up-regulated in response to abiotic stress. Moreover, the microbial community composition of maize rhizosphere soil after inoculating with strain SC2 was varied from the one after inoculating with mutant SC2-11. Our results provide new insights into the various genes involved in the salt resistance of strain SC2 and a theoretical basis for utilizing P. polymyxa in saline-alkaline environments.
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Affiliation(s)
- Chengqiang Wang
- College of Life Sciences, Shandong Engineering Research Center of Plant-Microbia Restoration for Saline-alkali Land, Shandong Key Laboratory of Agricultural Microbiology, National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an 271018, China.
| | - Jian Pei
- College of Life Sciences, Shandong Engineering Research Center of Plant-Microbia Restoration for Saline-alkali Land, Shandong Key Laboratory of Agricultural Microbiology, National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an 271018, China
| | - Hui Li
- College of Life Sciences, Shandong Engineering Research Center of Plant-Microbia Restoration for Saline-alkali Land, Shandong Key Laboratory of Agricultural Microbiology, National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an 271018, China
| | - Xiuling Zhu
- College of Life Sciences, Shandong Engineering Research Center of Plant-Microbia Restoration for Saline-alkali Land, Shandong Key Laboratory of Agricultural Microbiology, National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an 271018, China
| | - Yanan Zhang
- College of Life Sciences, Shandong Engineering Research Center of Plant-Microbia Restoration for Saline-alkali Land, Shandong Key Laboratory of Agricultural Microbiology, National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an 271018, China
| | - Yanjun Wang
- Institute of Wetland Agriculture and Ecology, Shandong Academy of Agricultural Sciences, Jinan 250100, China
| | - Wenjie Li
- College of Life Sciences, Shandong Engineering Research Center of Plant-Microbia Restoration for Saline-alkali Land, Shandong Key Laboratory of Agricultural Microbiology, National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an 271018, China
| | - Zhongyue Wang
- College of Life Sciences, Shandong Engineering Research Center of Plant-Microbia Restoration for Saline-alkali Land, Shandong Key Laboratory of Agricultural Microbiology, National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an 271018, China
| | - Kai Liu
- College of Life Sciences, Shandong Engineering Research Center of Plant-Microbia Restoration for Saline-alkali Land, Shandong Key Laboratory of Agricultural Microbiology, National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an 271018, China
| | - Binghai Du
- College of Life Sciences, Shandong Engineering Research Center of Plant-Microbia Restoration for Saline-alkali Land, Shandong Key Laboratory of Agricultural Microbiology, National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an 271018, China
| | - Juquan Jiang
- Department of Microbiology and Biotechnology, College of Life Sciences, Northeast Agricultural University, Harbin 150030, China.
| | - Dongying Zhao
- College of Life Sciences, Shandong Engineering Research Center of Plant-Microbia Restoration for Saline-alkali Land, Shandong Key Laboratory of Agricultural Microbiology, National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an 271018, China; College of Life Sciences, Dezhou University, Dezhou 253023, China.
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Yasmeen T, Arif MS, Tariq M, Akhtar S, Syrish A, Haidar W, Rizwan M, Hussain MI, Ahmad A, Ali S. Biofilm producing plant growth promoting bacteria in combination with glycine betaine uplift drought stress tolerance of maize plant. FRONTIERS IN PLANT SCIENCE 2024; 15:1327552. [PMID: 38405588 PMCID: PMC10884199 DOI: 10.3389/fpls.2024.1327552] [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: 10/25/2023] [Accepted: 01/05/2024] [Indexed: 02/27/2024]
Abstract
Introduction The escalating threat of drought poses a significant challenge to sustainable food production and human health, as water scarcity adversely impacts various aspects of plant physiology. Maize, a cornerstone in staple cereal crops, faces the formidable challenge of drought stress that triggers a series of transformative responses in the plant. Methods The present study was carried out in two sets of experiments. In first experiment, drought stress was applied after maintaining growth for 45 days and then irrigation was skipped, and plant samples were collected at 1st, 3rd and 6th day of drought interval for evaluation of changes in plant growth, water relation (relative water content) and antioxidants activity by inoculating indigenously isolated drought tolerant biofilm producing rhizobacterial isolates (Bacillus subtilis SRJ4, Curtobacterium citreum MJ1). In the second experiment, glycine betaine was applied as osmoregulator in addition to drought tolerant PGPR to perceive modulation in photosynthetic pigments (Chlorophyll a and b) and plant growth under varying moisture stress levels (100, 75 and 50% FC). Results and discussion Results of the study revealed upsurge in root and shoot length, fresh and dry biomass of root and shoot besides increasing chlorophyll contents in water stressed inoculated plants compared to uninoculated plants. Glycine betaine application resulted in an additional boost to plant growth and photosynthetic pigments, when applied in combination with bacterial inoculants. However, both bacterial inoculants behaved differently under drought stress as evident from their biochemical and physiological attributes. Isolate SRJ4 proved to be superior for its potential to express antioxidant activity, leaf water potential and relative water contents and drought responsive gene expression while isolate MJ1 showed exclusive increase in root dry biomass and plant P contents. Though it is quite difficult to isolate the bacterial isolates having both plant growth promoting traits and drought tolerance together yet, such biological resources could be an exceptional option to be applied for improving crop productivity and sustainable agriculture under abiotic stresses. By exploring the combined application of PGPR and glycine betaine, the study seeks to provide insights into potential strategies for developing sustainable agricultural practices aimed at improving crop resilience under challenging environmental conditions.
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Affiliation(s)
- Tahira Yasmeen
- Department of Environmental Sciences, Government College University Faisalabad, Faisalabad, Pakistan
| | - Muhammad Saleem Arif
- Department of Environmental Sciences, Government College University Faisalabad, Faisalabad, Pakistan
| | - Mohsin Tariq
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Sadia Akhtar
- Department of Environmental Sciences, Government College University Faisalabad, Faisalabad, Pakistan
| | - Afira Syrish
- Department of Environmental Sciences, Government College University Faisalabad, Faisalabad, Pakistan
| | - Waqas Haidar
- Department of Environmental Sciences, Government College University Faisalabad, Faisalabad, Pakistan
| | - Muhammad Rizwan
- Department of Environmental Sciences, Government College University Faisalabad, Faisalabad, Pakistan
| | | | - Ajaz Ahmad
- Department of Clinical Pharmacy, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Shafaqat Ali
- Department of Environmental Sciences, Government College University Faisalabad, Faisalabad, Pakistan
- Department of Biological Sciences and Technology, China Medical University, Taichung, Taiwan
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Iloabuchi K, Spiteller D. Bacillus sp. G2112 Detoxifies Phenazine-1-carboxylic Acid by N5 Glucosylation. Molecules 2024; 29:589. [PMID: 38338334 PMCID: PMC10856480 DOI: 10.3390/molecules29030589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 01/22/2024] [Accepted: 01/23/2024] [Indexed: 02/12/2024] Open
Abstract
Microbial symbionts of plants constitute promising sources of biocontrol organisms to fight plant pathogens. Bacillus sp. G2112 and Pseudomonas sp. G124 isolated from cucumber (Cucumis sativus) leaves inhibited the plant pathogens Erwinia and Fusarium. When Bacillus sp. G2112 and Pseudomonas sp. G124 were co-cultivated, a red halo appeared around Bacillus sp. G2112 colonies. Metabolite profiling using liquid chromatography coupled to UV and mass spectrometry revealed that the antibiotic phenazine-1-carboxylic acid (PCA) released by Pseudomonas sp. G124 was transformed by Bacillus sp. G2112 to red pigments. In the presence of PCA (>40 µg/mL), Bacillus sp. G2112 could not grow. However, already-grown Bacillus sp. G2112 (OD600 > 1.0) survived PCA treatment, converting it to red pigments. These pigments were purified by reverse-phase chromatography, and identified by high-resolution mass spectrometry, NMR, and chemical degradation as unprecedented 5N-glucosylated phenazine derivatives: 7-imino-5N-(1'β-D-glucopyranosyl)-5,7-dihydrophenazine-1-carboxylic acid and 3-imino-5N-(1'β-D-glucopyranosyl)-3,5-dihydrophenazine-1-carboxylic acid. 3-imino-5N-(1'β-D-glucopyranosyl)-3,5-dihydrophenazine-1-carboxylic acid did not inhibit Bacillus sp. G2112, proving that the observed modification constitutes a resistance mechanism. The coexistence of microorganisms-especially under natural/field conditions-calls for such adaptations, such as PCA inactivation, but these can weaken the potential of the producing organism against pathogens and should be considered during the development of biocontrol strategies.
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Affiliation(s)
- Kenechukwu Iloabuchi
- Department Chemical Ecology/Biological Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany;
- Department of Biochemistry, Faculty of Biological Sciences, University of Nigeria Nsukka, Obukpa Road, Nsukka 410105, Nigeria
| | - Dieter Spiteller
- Department Chemical Ecology/Biological Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany;
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Yang N, Røder HL, Wicaksono WA, Wassermann B, Russel J, Li X, Nesme J, Berg G, Sørensen SJ, Burmølle M. Interspecific interactions facilitate keystone species in a multispecies biofilm that promotes plant growth. THE ISME JOURNAL 2024; 18:wrae012. [PMID: 38365935 PMCID: PMC10938371 DOI: 10.1093/ismejo/wrae012] [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: 12/19/2023] [Revised: 01/04/2024] [Accepted: 01/29/2024] [Indexed: 02/18/2024]
Abstract
Microorganisms colonizing plant roots co-exist in complex, spatially structured multispecies biofilm communities. However, little is known about microbial interactions and the underlying spatial organization within biofilm communities established on plant roots. Here, a well-established four-species biofilm model (Stenotrophomonas rhizophila, Paenibacillus amylolyticus, Microbacterium oxydans, and Xanthomonas retroflexus, termed as SPMX) was applied to Arabidopsis roots to study the impact of multispecies biofilm on plant growth and the community spatial dynamics on the roots. SPMX co-culture notably promoted root development and plant biomass. Co-cultured SPMX increased root colonization and formed multispecies biofilms, structurally different from those formed by monocultures. By combining 16S rRNA gene amplicon sequencing and fluorescence in situ hybridization with confocal laser scanning microscopy, we found that the composition and spatial organization of the four-species biofilm significantly changed over time. Monoculture P. amylolyticus colonized plant roots poorly, but its population and root colonization were highly enhanced when residing in the four-species biofilm. Exclusion of P. amylolyticus from the community reduced overall biofilm production and root colonization of the three species, resulting in the loss of the plant growth-promoting effects. Combined with spatial analysis, this led to identification of P. amylolyticus as a keystone species. Our findings highlight that weak root colonizers may benefit from mutualistic interactions in complex communities and hereby become important keystone species impacting community spatial organization and function. This work expands the knowledge on spatial organization uncovering interspecific interactions in multispecies biofilm communities on plant roots, beneficial for harnessing microbial mutualism promoting plant growth.
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Affiliation(s)
- Nan Yang
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Henriette L Røder
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen 2100, Denmark
- Section for Microbiology and Fermentation, Department of Food Science, University of Copenhagen, Copenhagen 2100, Denmark
| | - Wisnu Adi Wicaksono
- Institute of Environmental Biotechnology, Graz University of Technology, Graz 8010, Austria
| | - Birgit Wassermann
- Institute of Environmental Biotechnology, Graz University of Technology, Graz 8010, Austria
| | - Jakob Russel
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Xuanji Li
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Joseph Nesme
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Gabriele Berg
- Institute of Environmental Biotechnology, Graz University of Technology, Graz 8010, Austria
| | - Søren J Sørensen
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Mette Burmølle
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen 2100, Denmark
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Zhang J, Huang X, Yang S, Huang A, Ren J, Luo X, Feng S, Li P, Li Z, Dong P. Endophytic Bacillus subtilis H17-16 effectively inhibits Phytophthora infestans, the pathogen of potato late blight, and its potential application. PEST MANAGEMENT SCIENCE 2023; 79:5073-5086. [PMID: 37572366 DOI: 10.1002/ps.7717] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 08/03/2023] [Accepted: 08/13/2023] [Indexed: 08/14/2023]
Abstract
BACKGROUND As a highly prevalent epidemic disease of potato, late blight caused by Phytophthora infestans poses a serious threat to potato yield and quality. At present, chemical fungicides are mainly used to control potato late blight, but long-term overuse of chemical fungicides may lead to environmental pollution and human health threats. Endophytes, natural resources for plant diseases control, can promote plant growth, enhance plant resistance, and secrete antifungal substances. Therefore, there is an urgent need to find some beneficial endophytes to control potato late blight. RESULTS We isolated a strain of Bacillus subtilis H17-16 from potato healthy roots. It can significantly inhibit mycelial growth, sporangia germination and the pathogenicity of Phytophthora infestans, induce the resistance of potato to late blight, and promote potato growth. In addition, H17-16 has the ability to produce protease, volatile compounds (VOCs) and form biofilms. After H17-16 treatment, most of the genes involved in metabolism, virulence and drug resistance of Phytophthora infestans were down-regulated significantly, and the genes related to ribosome biogenesis were mainly up-regulated. Moreover, field and postharvest application of H17-16 can effectively reduce the occurrence of potato late blight, and the combination of H17-16 with chitosan or chemical fungicides had a better effect than single H17-16. CONCLUSION Our results reveal that Bacillus subtilis H17-16 has great potential as a natural fungicide for controlling potato late blight, laying a theoretical basis for its development as a biological control agent. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Jiaomei Zhang
- School of Life Sciences, Chongqing University, Chongqing, China
- Chongqing Key Laboratory of Biology and Genetic Breeding for Tuber and Root Crops, Chongqing, China
| | - Xiaoqing Huang
- School of Life Sciences, Chongqing University, Chongqing, China
- Chongqing Key Laboratory of Biology and Genetic Breeding for Tuber and Root Crops, Chongqing, China
| | - Shidong Yang
- Shandong Nongdeli Biotechnology Co., Ltd, Jinan, China
| | - Airong Huang
- School of Life Sciences, Chongqing University, Chongqing, China
- Chongqing Key Laboratory of Biology and Genetic Breeding for Tuber and Root Crops, Chongqing, China
| | - Jie Ren
- School of Life Sciences, Chongqing University, Chongqing, China
- Chongqing Key Laboratory of Biology and Genetic Breeding for Tuber and Root Crops, Chongqing, China
| | - Xunguang Luo
- School of Life Sciences, Chongqing University, Chongqing, China
- Chongqing Key Laboratory of Biology and Genetic Breeding for Tuber and Root Crops, Chongqing, China
| | - Shun Feng
- School of Life Sciences, Chongqing University, Chongqing, China
- Chongqing Key Laboratory of Biology and Genetic Breeding for Tuber and Root Crops, Chongqing, China
| | - Peihua Li
- College of Agronomy, Xichang University, Xichang, China
| | - Zhengguo Li
- School of Life Sciences, Chongqing University, Chongqing, China
- Key Laboratory of Plant Hormones and Development Regulation of Chongqing, Chongqing, China
| | - Pan Dong
- School of Life Sciences, Chongqing University, Chongqing, China
- Chongqing Key Laboratory of Biology and Genetic Breeding for Tuber and Root Crops, Chongqing, China
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Yu C, Qiao J, Ali Q, Jiang Q, Song Y, Zhu L, Gu Q, Borriss R, Dong S, Gao X, Wu H. degQ associated with the degS/degU two-component system regulates biofilm formation, antimicrobial metabolite production, and biocontrol activity in Bacillus velezensis DMW1. MOLECULAR PLANT PATHOLOGY 2023; 24:1510-1521. [PMID: 37731193 PMCID: PMC10632791 DOI: 10.1111/mpp.13389] [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: 04/26/2023] [Revised: 07/13/2023] [Accepted: 09/05/2023] [Indexed: 09/22/2023]
Abstract
The gram-positive bacterium Bacillus velezensis strain DMW1 produces a high level of antimicrobial metabolites that can suppress the growth of phytopathogens. We investigated the mechanism used by degQ and the degS/degU two-component system to regulate the biocontrol characteristics of DMW1. When degQ and degU were deleted, the biofilm formation, cell motility, colonization activities, and antifungal abilities of ΔdegQ and ΔdegU were significantly reduced compared to wild-type DMW1. The expression levels of biofilm-related genes (epsA, epsB, epsC, and tasA) and swarming-related genes (swrA and swrB) were all down-regulated. We also evaluated the impact on secondary metabolites of these two genes. The degQ and degU genes reduced surfactin and macrolactin production and up-regulated the production of fengycin, iturin, bacillaene, and difficidin metabolites. The reverse transcription-quantitative PCR results were consistent with these observations. Electrophoretic mobility shift assay and microscale thermophoresis revealed that DegU can bind to the promoter regions of these six antimicrobial metabolite genes and regulate their synthesis. In conclusion, we provided systematic evidence to demonstrate that the degQ and degU genes are important regulators of multicellular behaviour and antimicrobial metabolic processes in B. velezensis DMW1 and suggested novel amenable strains to be used for the industrial production of antimicrobial metabolites.
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Affiliation(s)
- Chenjie Yu
- College of Plant Protection, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Sanya Institute of Nanjing Agricultural UniversityNanjing Agricultural UniversityNanjingChina
| | - Junqing Qiao
- Jiangsu Academy of Agricultural SciencesInstitute of Plant ProtectionNanjingChina
| | - Qurban Ali
- College of Plant Protection, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Sanya Institute of Nanjing Agricultural UniversityNanjing Agricultural UniversityNanjingChina
| | - Qifan Jiang
- College of Plant Protection, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Sanya Institute of Nanjing Agricultural UniversityNanjing Agricultural UniversityNanjingChina
| | - Yan Song
- College of Plant Protection, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Sanya Institute of Nanjing Agricultural UniversityNanjing Agricultural UniversityNanjingChina
| | - Linli Zhu
- College of Plant Protection, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Sanya Institute of Nanjing Agricultural UniversityNanjing Agricultural UniversityNanjingChina
| | - Qin Gu
- College of Plant Protection, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Sanya Institute of Nanjing Agricultural UniversityNanjing Agricultural UniversityNanjingChina
| | - Rainer Borriss
- Institut für BiologieHumboldt University BerlinBerlinGermany
| | - Suomeng Dong
- College of Plant Protection, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Sanya Institute of Nanjing Agricultural UniversityNanjing Agricultural UniversityNanjingChina
| | - Xuewen Gao
- College of Plant Protection, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Sanya Institute of Nanjing Agricultural UniversityNanjing Agricultural UniversityNanjingChina
| | - Huijun Wu
- College of Plant Protection, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Sanya Institute of Nanjing Agricultural UniversityNanjing Agricultural UniversityNanjingChina
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Mehmood N, Saeed M, Zafarullah S, Hyder S, Rizvi ZF, Gondal AS, Jamil N, Iqbal R, Ali B, Ercisli S, Kupe M. Multifaceted Impacts of Plant-Beneficial Pseudomonas spp. in Managing Various Plant Diseases and Crop Yield Improvement. ACS OMEGA 2023; 8:22296-22315. [PMID: 37396244 PMCID: PMC10308577 DOI: 10.1021/acsomega.3c00870] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 05/18/2023] [Indexed: 07/04/2023]
Abstract
The modern agricultural system has issues with the reduction of agricultural productivity due to a wide range of abiotic and biotic stresses. It is also expected that in the future the entire world population may rapidly increase and will surely demand more food. Farmers now utilize a massive quantity of synthetic fertilizers and pesticides for disease management and to increase food production. These synthetic fertilizers badly affect the environment, the texture of the soil, plant productivity, and human health. However, agricultural safety and sustainability depend on an ecofriendly and inexpensive biological application. In contrast to synthetic fertilizers, soil inoculation with plant-growth-promoting rhizobacteria (PGPR) is one of the excellent alternative options. In this regard, we focused on the best PGPR genera, Pseudomonas, which exists in the rhizosphere as well as inside the plant's body and plays a role in sustainable agriculture. Many Pseudomonas spp. control plant pathogens and play an effective role in disease management through direct and indirect mechanisms. Pseudomonas spp. fix the amount of atmospheric nitrogen, solubilize phosphorus and potassium, and also produce phytohormones, lytic enzymes, volatile organic compounds, antibiotics, and secondary metabolites during stress conditions. These compounds stimulate plant growth by inducing systemic resistance and by inhibiting the growth of pathogens. Furthermore, pseudomonads also protect plants during different stress conditions like heavy metal pollution, osmosis, temperature, oxidative stress, etc. Now, several Pseudomonas-based commercial biological control products have been promoted and marketed, but there are a few limitations that hinder the development of this technology for extensive usage in agricultural systems. The variability among the members of Pseudomonas spp. draws attention to the huge research interest in this genus. There is a need to explore the potential of native Pseudomonas spp. as biocontrol agents and to use them in biopesticide development to support sustainable agriculture.
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Affiliation(s)
- Najaf Mehmood
- Department
of Botany, Government College Women University
Sialkot, Sialkot 51310, Pakistan
| | - Mahnoor Saeed
- Department
of Botany, Government College Women University
Sialkot, Sialkot 51310, Pakistan
| | - Sana Zafarullah
- Department
of Botany, Government College Women University
Sialkot, Sialkot 51310, Pakistan
| | - Sajjad Hyder
- Department
of Botany, Government College Women University
Sialkot, Sialkot 51310, Pakistan
| | - Zarrin Fatima Rizvi
- Department
of Botany, Government College Women University
Sialkot, Sialkot 51310, Pakistan
| | - Amjad Shahzad Gondal
- Department
of Plant Pathology, Bahauddin Zakariya University, Multan 60000, Pakistan
| | - Nuzhat Jamil
- Department
of Botany, University of the Punjab, Quaid-i-Azam Campus, Lahore 54590, Pakistan
| | - Rashid Iqbal
- Department
of Agronomy, Faculty of Agriculture and Environment, The Islamia University of Bahawalpur Pakistan, Bahawalpur 63100, Pakistan
| | - Baber Ali
- Department
of Plant Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Sezai Ercisli
- Department
of Horticulture, Faculty of Agriculture, Ataturk University, Erzurum 25240, Türkiye
- HGF
Agro, Ata Teknokent, Erzurum TR-25240, Türkiye
| | - Muhammed Kupe
- Department
of Horticulture, Faculty of Agriculture, Ataturk University, Erzurum 25240, Türkiye
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10
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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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11
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Ahmad Ansari F, Ahmad I, Pichtel J. Synergistic effects of biofilm-producing PGPR strains on wheat plant colonization, growth and soil resilience under drought stress. Saudi J Biol Sci 2023; 30:103664. [PMID: 37213696 PMCID: PMC10193011 DOI: 10.1016/j.sjbs.2023.103664] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 04/03/2023] [Accepted: 04/21/2023] [Indexed: 05/23/2023] Open
Abstract
Drought stress substantially impedes crop productivity throughout the world. Microbial based approaches have been considered a potential possibility and are under study. Based on our prior screening examination, two distinct and novel biofilm-forming PGPR strains namely Bacillus subtilis-FAB1 and Pseudomonas azotoformans-FAP3 are encompassed in this research. Bacterial biofilm development on glass surface, microtiter plate and seedling roots were assessed and characterized quantitatively and qualitatively by light and scanning electron microscopy. Above two isolates were further evaluated for their consistent performance by inoculating on wheat plants in a pot-soil system under water stresses. Bacterial moderate tolerance to ten-day drought was recorded on the application of individual strains with wheat plants; however, the FAB1 + FAP3 consortium expressively improved wheat survival during drought. The strains FAB1 and FAP3 displayed distinct and multifunctional plant growth stimulating attributes as well as effective roots and rhizosphere colonization in combination which could provide sustained wheat growth during drought. FAB1 and FAP3-induced alterations cooperatively conferred improved plant drought tolerance by controlling physiological traits (gs, Ci, E, iWUE and PN), stress indicators (SOD, CAT, GR, proline and MDA content) and also maintained physico-chemical attributes and hydrolytic enzymes including DHA, urease, ALP, protease, ACP and β glucosidase in the soil. Our findings could support future efforts to enhance plant drought tolerance by engineering the rhizobacterial biofilms and associated attributes which requires in-depth exploration and exploiting potential native strains for local agricultural application.
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Affiliation(s)
- Firoz Ahmad Ansari
- Biofilm Research Lab., Department of Agricultural Microbiology, Faculty of Agricultural Sciences, Aligarh Muslim University, Aligarh 202002, India
- Corresponding author at: Department of Agricultural Microbiology Faculty of Agricultural Sciences AMU, Aligarh, India.
| | - Iqbal Ahmad
- Biofilm Research Lab., Department of Agricultural Microbiology, Faculty of Agricultural Sciences, Aligarh Muslim University, Aligarh 202002, India
| | - John Pichtel
- Department of Environment, Geology and Natural Resources, Ball State University, Muncie, IN 47306, USA
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12
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Dai W, Liu Y, Yao D, Wang N, Ye X, Cui Z, Wang H. Phylogenetic diversity of stochasticity-dominated predatory myxobacterial community drives multi-nutrient cycling in typical farmland soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 871:161680. [PMID: 36682558 DOI: 10.1016/j.scitotenv.2023.161680] [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: 11/13/2022] [Revised: 01/03/2023] [Accepted: 01/14/2023] [Indexed: 06/17/2023]
Abstract
Predatory myxobacteria are keystone taxa in the soil microbial food web that potentially regulate soil microbial community structure and ecosystem functions. However, little is known about the community assembly processes of myxobacteria in typical farmland soils over large geographic scales, in addition to their relationship with soil multi-nutrient cycling. Here, we used high-throughput sequencing techniques and phylogenetic null modeling analysis to investigate the distribution patterns and assembly processes of myxobacteria communities, in addition to interactions between myxobacteria communities and soil multi-nutrient cycling. Anaeromyxobacter (28.5 %) and Haliangium (19.6 %) were the dominant myxobacteria genera in all samples, and myxobacteria community similarities exhibited distinct distance-decay relationships. Stochastic processes (~77.8 %) were the dominant ecological processes driving the assembly of predatory myxobacteria communities over large geographical scales and under three fertilization regimes. Myxobacteria community structure was influenced by geographic factors (location and climate), soil factors (soil pH, soil organic carbon, total nitrogen, and total potassium), and fertilization, with myxobacteria community assembly being more sensitive to geographic factors. Organic-inorganic combined fertilization (NPKM) increased the proportions of deterministic processes in myxobacteria community assembly. Moreover, myxobacteria community assembly and diversity were closely associated with soil multi-nutrient cycling. Hence, myxobacteria phylogenetic α-diversity represented by NTI index is a potential bioindicators for soil multi-nutrient cycling. Overall, our findings comprehensively reveal the mechanisms of assembly of myxobacteria communities in soils over large geographic scales, and provide a theoretical basis for further research on the role of predatory bacteria on soil nutrient cycling in agro-ecosystems.
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Affiliation(s)
- Wei Dai
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100000, China
| | - Yang Liu
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100000, China
| | - Dandan Yao
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100000, China
| | - Ning Wang
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100000, China
| | - Xianfeng Ye
- Key Laboratory of Agricultural Environmental Microbiology of Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhongli Cui
- Key Laboratory of Agricultural Environmental Microbiology of Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Hui Wang
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100000, China.
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13
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Chaudhary R, Kumar V, Gupta S, Naik B, Prasad R, Mishra S, Saris PEJ, Kumar V. Finger Millet ( Eleusine coracana) Plant-Endophyte Dynamics: Plant Growth, Nutrient Uptake, and Zinc Biofortification. Microorganisms 2023; 11:microorganisms11040973. [PMID: 37110396 PMCID: PMC10143119 DOI: 10.3390/microorganisms11040973] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 03/30/2023] [Accepted: 04/05/2023] [Indexed: 04/29/2023] Open
Abstract
Endophytic fungi and bacteria were isolated from finger millet and their effects on finger millet growth parameters and zinc and NPK contents in grains were studied. Out of 70 fungal and 112 bacterial endophytes, the two best fungal and bacterial isolates were selected on the basis of zinc solubilization and plant-growth-promoting attributes. The fungal isolates identified were Aspergillus terreus and Lecanicillium sp., and the bacterial isolates were Pseudomonas bijieensis and Priestia megaterium. The endophytic zinc, NPK mobilization, and plant-growth-promoting efficacy were determined in a pot experiment with zinc carbonate as the zinc source. Endophytic-primed plants showed enhanced shoot and root lengths compared to the unprimed control. Endophytes increased the zinc content in grains by between 12.12% and 18.80% compared to control plants. Endophytes also augmented the NPK concentrations in seeds compared to control plants and exhibited stability in a diverse range of pHs, temperatures, and NaCl concentrations, and exhibited growth on various carbohydrate and nitrogen sources. This is the first study reporting the interaction of Aspergillus terreus, Lecanicillium sp., Pseudomonas bijieensis, and Priestia megaterium with finger millet for grain Zn biofortification and NPK concentration enhancement. This study indicated that zinc-dissolving endophytes possess the potential for enhancing the zinc and NPK content in grains in addition to the plant-growth-promoting attributes.
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Affiliation(s)
- Renu Chaudhary
- Himalayan School of Biosciences, Swami Rama Himalayan University, Jolly Grant, Dehradun 248016, India
| | - Vijay Kumar
- Himalayan School of Biosciences, Swami Rama Himalayan University, Jolly Grant, Dehradun 248016, India
| | - Sanjay Gupta
- Himalayan School of Biosciences, Swami Rama Himalayan University, Jolly Grant, Dehradun 248016, India
| | - Bindu Naik
- Department of Life Sciences, Graphic Era (Deemed to be) University, Bell Road, Clement Town, Dehradun 248002, India
| | - Ram Prasad
- Department of Botany, School of Life Sciences, Mahatma Gandhi Central University, Motihari 845401, India
| | - Sadhna Mishra
- Faculty of Agricultural Sciences, GLA University, Mathura 281406, India
| | - Per Erik Joakim Saris
- Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, 00100 Helsinki, Finland
| | - Vivek Kumar
- Himalayan School of Biosciences, Swami Rama Himalayan University, Jolly Grant, Dehradun 248016, India
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14
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Lyng M, Kovács ÁT. Frenemies of the soil: Bacillus and Pseudomonas interspecies interactions. Trends Microbiol 2023:S0966-842X(23)00050-1. [PMID: 36878770 DOI: 10.1016/j.tim.2023.02.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 02/10/2023] [Accepted: 02/13/2023] [Indexed: 03/07/2023]
Abstract
Bacillus and Pseudomonas ubiquitously occur in natural environments and are two of the most intensively studied bacterial genera in the soil. They are often coisolated from environmental samples, and as a result, several studies have experimentally cocultured bacilli and pseudomonads to obtain emergent properties. Even so, the general interaction between members of these genera is virtually unknown. In the past decade, data on interspecies interactions between natural isolates of Bacillus and Pseudomonas has become more detailed, and now, molecular studies permit mapping of the mechanisms behind their pairwise ecology. This review addresses the current knowledge about microbe-microbe interactions between strains of Bacillus and Pseudomonas and discusses how we can attempt to generalize the interaction on a taxonomic and molecular level.
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Affiliation(s)
- Mark Lyng
- Bacterial Interactions and Evolution group, DTU Bioengineering, Technical University of Denmark, Kgs Lyngby 2800, Denmark
| | - Ákos T Kovács
- Bacterial Interactions and Evolution group, DTU Bioengineering, Technical University of Denmark, Kgs Lyngby 2800, Denmark; Institute of Biology, Leiden University, Leiden, The Netherlands.
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15
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Wang J, Zhao S, Xu S, Zhao W, Zhang X, Lei Y, Zhai H, Huang Z. Co-inoculation of antagonistic Bacillus velezensis FH-1 and Brevundimonas diminuta NYM3 promotes rice growth by regulating the structure and nitrification function of rhizosphere microbiome. Front Microbiol 2023; 14:1101773. [PMID: 36846752 PMCID: PMC9948033 DOI: 10.3389/fmicb.2023.1101773] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 01/17/2023] [Indexed: 02/11/2023] Open
Abstract
Microbial inoculation with plant growth-promoting microorganisms (PGPMs) is one of the most promising technologies to solve the current global challenges. Co-inoculants is more efficient and stable than mono-inoculants. However, the growth promoting mechanism of co-inoculants in complex soil system is still poorly understood. In this study, the effects on rice, soil and the microbiome of the mono-inoculant Bacillus velezensis FH-1 (F) and Brevundimonas diminuta NYM3 (N) and the co-inoculant FN obtained in previous works were compared. Correlation analysis and PLS-PM were used to explore the primary mechanism of different inoculants promoting rice growth. We hypothesized that inoculants promoted plant growth (i) by themselves, (ii) by improving soil nutrient availability or (iii) by regulating the rhizosphere microbiome in complex soil system. We also assumed that different inoculants had different ways of promoting plant growth. The results showed that FN significantly promoted rice growth and nitrogen absorption and slightly increased soil total nitrogen and microbial network complexity compared with F, N and the control (CK). B. velezensis FH-1 and B. diminuta NYM3 interfered with each other's colonization in FN. FN increased the complexity of the microbial network compared to F and N. The bacterial community of FN was quite different from CK and N, while the fungal community was not significantly different from other treatments. The species and functions enriched or inhibited by FN are part of F. The correlation analysis and PLS-PM results showed that inoculants (F/N/FN) promoted the growth of rice mainly by regulating the rhizosphere microbiome rather than by themselves or by improving soil nutrient availability. Co-inoculant FN promotes rice growth specifically by enhancing microbial nitrification function through enriching related species compared with F or N. This may provide theoretical guidance for the construction and application of co-inoculants in the future.
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Affiliation(s)
- Jingjing Wang
- Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China,National Technology Innovation Center of Synthetic Biology, Tianjin, China,*Correspondence: Jingjing Wang, ✉
| | - Siqi Zhao
- Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China,National Technology Innovation Center of Synthetic Biology, Tianjin, China
| | - Song Xu
- Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China,National Technology Innovation Center of Synthetic Biology, Tianjin, China
| | - Wei Zhao
- Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China,National Technology Innovation Center of Synthetic Biology, Tianjin, China
| | - Xiaoxia Zhang
- Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China,National Technology Innovation Center of Synthetic Biology, Tianjin, China
| | - Yu Lei
- Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China,National Technology Innovation Center of Synthetic Biology, Tianjin, China,Core Facility, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Huanhuan Zhai
- Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China,National Technology Innovation Center of Synthetic Biology, Tianjin, China,Core Facility, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Zhiyong Huang
- Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China,National Technology Innovation Center of Synthetic Biology, Tianjin, China,Zhiyong Huang, ✉
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16
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Vio SA, Galar ML, Gortari MC, Balatti P, Garbi M, Lodeiro AR, Luna MF. Multispecies Bacterial Bio-Input: Tracking and Plant-Growth-Promoting Effect on Lettuce var. sagess. PLANTS (BASEL, SWITZERLAND) 2023; 12:736. [PMID: 36840083 PMCID: PMC9962684 DOI: 10.3390/plants12040736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 01/23/2023] [Accepted: 01/25/2023] [Indexed: 06/18/2023]
Abstract
The use of multispecies bacterial bio-inputs is a promising strategy for sustainable crop production over the use of single-species inoculants. Studies of the use of multispecies bio-inputs in horticultural crops are scarce, not only on the growth-promoting effects of each bacterium within the formulation, but also on their compatibility and persistence in the root environment. In this work, we described that a multispecies bacterial bio-input made up of Azospirillum argentinense Az39, Gluconacetobacter diazotrophicus PAL-5, Pseudomonas protegens Pf-5 and Bacillus sp. Dm-B10 improved lettuce plant growth more effectively than when these strains were inoculated as single-species bio-inputs. Bacteria persisted together (were compatible) and also colonized seedling roots of lettuce plants grown in controlled conditions. Interestingly, colonization was highly related to an early and enhanced growth of seedlings grown in the nursery. A similar effect on plant growth was found in lettuce plants in a commercial greenhouse production in the peri-urban area of La Plata City, Buenos Aires, Argentina. To our knowledge, this is the first study demonstrating that a synthetic mixture of bacteria can colonize and persist on lettuce plants, and also showing their synergistic beneficial effect both in the nursery greenhouse as well as the commercial production farm.
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Affiliation(s)
- Santiago A. Vio
- Centro de Investigación y Desarrollo en Fermentaciones Industriales, CINDEFI (CONICET/UNLP), Calle 50 227, La Plata 1900, Argentina
| | - María Lina Galar
- Centro de Investigación y Desarrollo en Fermentaciones Industriales, CINDEFI (CONICET/UNLP), Calle 50 227, La Plata 1900, Argentina
| | - María Cecilia Gortari
- Centro de Investigación y Desarrollo en Fermentaciones Industriales, CINDEFI (CONICET/UNLP), Calle 50 227, La Plata 1900, Argentina
- Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CIC-PBA), Calle 526 e/ Calles 10 y 11, La Plata 1900, Argentina
| | - Pedro Balatti
- Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CIC-PBA), Calle 526 e/ Calles 10 y 11, La Plata 1900, Argentina
- Centro de Investigaciones de Fitopatología, CIDEFI (CIC–UNLP), Calle 60 y 119, La Plata 1900, Argentina
| | - Mariana Garbi
- Climatología y Fenología Agrícola, Facultad de Ciencias Agrarias y Forestales, UNLP, Calle 60 y 119, La Plata 1900, Argentina
| | - Aníbal Roberto Lodeiro
- Instituto de Biotecnología y Biología Molecular, IBBM (CONICET/UNLP), Calle 47 y 115, La Plata 1900, Argentina
- Genética, Facultad de Ciencias Agrarias y Forestales, UNLP, Calle 60 y 119, La Plata 1900, Argentina
| | - María Flavia Luna
- Centro de Investigación y Desarrollo en Fermentaciones Industriales, CINDEFI (CONICET/UNLP), Calle 50 227, La Plata 1900, Argentina
- Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CIC-PBA), Calle 526 e/ Calles 10 y 11, La Plata 1900, Argentina
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17
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Liu Y, Zhang B, Han YH, Yao Y, Guo P. Involvement of exogenous arsenic-reducing bacteria in root surface biofilm formation promoted phytoextraction of arsenic. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:160158. [PMID: 36379332 DOI: 10.1016/j.scitotenv.2022.160158] [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: 10/17/2022] [Accepted: 11/09/2022] [Indexed: 06/16/2023]
Abstract
Root surface biofilm (RSB) is the last window for pollutants entering plant roots and thus plays a critical role in the phytoextraction of pollutants. Exogenous arsenic-reducing bacteria (EARB) have been adopted to enhance the phytoextraction of arsenic (As). However, whether EARB would be involved in RSB formation together with indigenous bacteria and the role of EARB involvement in As phytoextraction are still unknown. Herein, two EARB strains and two phytoextractors (wheat and maize) were selected to investigate the involvement of EARB in RSB formation and its role in As phytoextraction. Results showed that EARB successfully participated in RSB formation together with indigenous bacteria, attributing to their strong chemotaxis and biofilm formation abilities induced by root exudates. The involvement of EARB in RSB formation significantly enhanced As accumulation in plant roots, since more arsenite (As(III)) caused by arsenate (As(V)) reduction in RSB was absorbed by roots. Its underlying mechanism was further elucidated. EARB involvement increased phylum Proteobacteria to produce more siderophores in RSB. Siderophores then improved photosynthesis by increasing catalase and peroxidase activities and decreasing the malondialdehyde of plants. These actions further raised the shoot fresh weight to enhance As accumulation in plant roots. Moreover, mesophyll cell in wheat has a stronger As(V) reduction ability than that in maize, resulting in opposite distribution patterns of As(III) and As(V) in wheat and maize shoots. This study provides a new understanding of phytoextraction enhanced by exogenous bacteria and fills the gap in the role of EARB in As phytoextraction from the perspective of the RSB microregion.
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Affiliation(s)
- Yibo Liu
- Key Laboratory of Groundwater Resources and Environment Ministry of Education, College of New Energy and Environment, Jilin University, Changchun 130012, PR China; Jilin Provincial Key Laboratory of Water Resources and Environment, Jilin University, Changchun 130012, PR China
| | - Baiyu Zhang
- Department of Civil Engineering, Faculty of Engineering and Applied Science, Memorial University, St. John's, NL A1B 3X5, Canada
| | - Yong-He Han
- College of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, P R, China; Fujian Key Laboratory of Pollution Control and Resource Reuse, Fuzhou 350007, PR China
| | - Ye Yao
- College of Physics, Jilin university, Changchun 130012, PR China
| | - Ping Guo
- Key Laboratory of Groundwater Resources and Environment Ministry of Education, College of New Energy and Environment, Jilin University, Changchun 130012, PR China; Jilin Provincial Key Laboratory of Water Resources and Environment, Jilin University, Changchun 130012, PR China.
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18
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Díaz-Manzano FE, Amora DX, Martínez-Gómez Á, Moelbak L, Escobar C. Biocontrol of Meloidogyne spp. in Solanum lycopersicum using a dual combination of Bacillus strains. FRONTIERS IN PLANT SCIENCE 2023; 13:1077062. [PMID: 36684755 PMCID: PMC9846617 DOI: 10.3389/fpls.2022.1077062] [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: 10/22/2022] [Accepted: 11/29/2022] [Indexed: 06/17/2023]
Abstract
Root-knot nematodes (RKNs, Meloidogyne spp.) are obligate plant parasites that constitute a significant pest for agriculture worldwide. They penetrate the plant roots, reducing the uptake of water and nutrients, causing a significant impact on crop yield. One alternative on focus now for nematode management is biological control. Rhizobacteria within the Bacillus genus show multiple modes of action against plant-parasitic nematodes (PPNs) that can act alone or in combination. In this context, we evaluated a dual-strain bacteria combination (B. paralicheniformi FMCH001 and B. subtilis FMCH002) to reduce nematode infection in tomato plants. We evaluated mortality of larvae from Meloidogyne javanica in vitro, as well as eggs hatching after the treatment. Atraction, penetration, establishment, and reproduction assays in vitro or in pots in tomato plants infected with M. javanica and treated/ untreated with the dual-strain bacteria combination were also performed. Additionally, morphometric parameters comparing giant cells size from galls of treated and untreated plants by using confocal microscopy were also measured. The results showed that this combination of strains has nematicidal properties in the pre-infection phase by decreasing the egg-hatching, juvenile survival, and attractiveness to the roots. Furthermore, nematode establishment, gall formation, and, remarkably, giant cell development was severely impaired after the bacterial treatment, suggesting interference with morphogenetic mechanisms induced by the nematode during GCs development within the plant. Nematode reproduction in tomato plants was reduced independently of the application mode in soil, before or after bacterial treatment. The dual-strain combination was also effective against other PPNs (i.e. Pratylenchus spp.) and in different crops (soybean). Therefore, combining B. paralicheniformis FMCH001 and B. subtilis FMCH002 is an efficient agent for the biological control of Meloidogyne spp. by interfering with different stages of the nematode cycle as a result of multiple modes of action.
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Affiliation(s)
- Fernando Evaristo Díaz-Manzano
- Área de Fisiología Vegetal, Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, Toledo, Spain
| | - Deisy X. Amora
- Chr Hansen A/S, AP Innovation Department, Hørsholm, Denmark
| | - Ángela Martínez-Gómez
- Área de Fisiología Vegetal, Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, Toledo, Spain
| | - Lars Moelbak
- Chr Hansen A/S, AP Innovation Department, Hørsholm, Denmark
| | - Carolina Escobar
- Área de Fisiología Vegetal, Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, Toledo, Spain
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Yang Z, Dong H, Zhang S, Jiang J, Zhu H, Yang H, Li L. Isolation and identification of mycorrhizal helper bacteria of Vaccinium uliginosum and their interaction with mycorrhizal fungi. Front Microbiol 2023; 14:1180319. [PMID: 37143547 PMCID: PMC10151510 DOI: 10.3389/fmicb.2023.1180319] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 03/28/2023] [Indexed: 05/06/2023] Open
Abstract
Mycorrhizal helper bacteria (MHB) can promote mycorrhizal fungal colonization and form mycorrhizal symbiosis structures. To investigate the effect of interactions between mycorrhizal beneficial microorganisms on the growth of blueberry, 45 strains of bacteria isolated from the rhizosphere soil of Vaccinium uliginosum were screened for potential MHB strains using the dry-plate confrontation assay and the bacterial extracellular metabolite promotion method. The results showed that the growth rate of mycelium of Oidiodendron maius 143, an ericoid mycorrhizal fungal strain, was increased by 33.33 and 77.77% for bacterial strains L6 and LM3, respectively, compared with the control in the dry-plate confrontation assay. In addition, the extracellular metabolites of L6 and LM3 significantly promoted the growth of O. maius 143 mycelium with an average growth rate of 40.9 and 57.1%, respectively, the cell wall-degrading enzyme activities and genes of O. maius 143 was significantly increased. Therefore, L6 and LM3 were preliminarily identified as potential MHB strains. In addition, the co-inoculated treatments significantly increased blueberry growth; increased the nitrate reductase, glutamate dehydrogenase, glutamine synthetase, and glutamate synthase activities in the leaves; and promoted nutrient uptake in blueberry. Based on the physiological, and 16S rDNA gene molecular analyses, we initially identified strain L6 as Paenarthrobacter nicotinovorans and LM3 as Bacillus circulans. Metabolomic analysis revealed that mycelial exudates contain large amounts of sugars, organic acids and amino acids, which can be used as substrates to stimulate the growth of MHB. In conclusion, L6 and LM3 and O. maius 143 promote each other's growth, while co-inoculation of L6 and LM3 with O. maius 143 can promote the growth of blueberry seedlings, providing a theoretical basis for further studies on the mechanism of ericoid mycorrhizal fungi-MHB-blueberry interactions. It laid the technical foundation for the exploitation of biocontrol strain resources and the development of biological fertilizer.
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Affiliation(s)
- Zhiyu Yang
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration (Northeast Forestry University), Ministry of Education, Harbin, China
- College of Life Science, Northeast Forestry University, Harbin, China
| | - Hui Dong
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration (Northeast Forestry University), Ministry of Education, Harbin, China
- College of Life Science, Northeast Forestry University, Harbin, China
| | - Sai Zhang
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration (Northeast Forestry University), Ministry of Education, Harbin, China
- College of Life Science, Northeast Forestry University, Harbin, China
| | - Jing Jiang
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration (Northeast Forestry University), Ministry of Education, Harbin, China
- College of Life Science, Northeast Forestry University, Harbin, China
| | - Haifeng Zhu
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration (Northeast Forestry University), Ministry of Education, Harbin, China
- College of Life Science, Northeast Forestry University, Harbin, China
| | - Hongyi Yang
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration (Northeast Forestry University), Ministry of Education, Harbin, China
- College of Life Science, Northeast Forestry University, Harbin, China
- *Correspondence: Hongyi Yang,
| | - Lili Li
- Institute of Forestry Science of Heilongjiang Province, Harbin, China
- Lili Li,
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20
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Mokeev DI, Volokhina IV, Telesheva EM, Evstigneeva SS, Grinev VS, Pylaev TE, Petrova LP, Shelud’ko AV. Resistance of Biofilms Formed by the Soil Bacterium Azospirillum brasilense to Osmotic Stress. Microbiology (Reading) 2022. [DOI: 10.1134/s0026261722601567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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21
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NG CWW, YAN WH, TSIM KWK, SO PS, XIA YT, TO CT. Effects of Bacillus subtilis and Pseudomonas fluorescens as the soil amendment. Heliyon 2022; 8:e11674. [PMID: 36439778 PMCID: PMC9691937 DOI: 10.1016/j.heliyon.2022.e11674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 10/08/2022] [Accepted: 11/10/2022] [Indexed: 11/18/2022] Open
Abstract
The application of soil beneficial bacteria (SBB) in agriculture is steadily increasing as it provides a promising way to replace chemical fertilisers and other supplements. Although the role of SBB as a biofertiliser is well understood, little is known about the response of soil physiochemical properties via the change in soil enzymatic activities with SBB growth. In this study, sterilised bulk soil was inoculated with Bacillus subtilis (BS) and Pseudomonas fluorescens (PF), which exhibit excellent characteristics in vitro for potentially improving soil quality. It is found that the contents of bioavailable nitrogen and ammonium in soil inoculated with SBB increased significantly, up to 34% and 57% relative to a control. This resulted from the enhancement of soil urease activity with BS and PF treatments by approximately 90% and 70%, respectively. The increased soil urease activity can be explained by the increased microorganism activity evident from the larger population size of BS (0.78–0.97 CFU mL−1/CFU mL−1) than PF (0.55–0.79 CFU mL−1/CFU mL−1) (p < 0.05). Results of principal component analysis also reinforce the interaction apparent in the significant relationship between soil urease activity and microbial biomass carbon (p < 0.05). Therefore, it can be concluded that the enhancement of soil enzymatic activities induced bulk soil fertility upregulation because of bacterial growth. These results demonstrate the application of SBB to be a promising strategy for bulk soil amendment, particularly nutrient restoration.
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Affiliation(s)
- Charles Wang Wai NG
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR, China
| | - Wen Hui YAN
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR, China
- Corresponding author.
| | - Karl Wah Keung TSIM
- Division of Life Science and Centre for Chinese Medicine, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR, China
| | - Pui San SO
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR, China
| | - Yi Teng XIA
- Division of Life Science and Centre for Chinese Medicine, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR, China
| | - Chun Ting TO
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR, China
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22
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Halotolerant rhizobacteria isolated from a mangrove forest alleviate saline stress in Musa acuminata cv. Berangan. Microbiol Res 2022; 265:127176. [PMID: 36088726 DOI: 10.1016/j.micres.2022.127176] [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: 10/08/2021] [Revised: 08/09/2022] [Accepted: 08/24/2022] [Indexed: 11/21/2022]
Abstract
Saline soils resulting from anthropogenic activity and climate change present a challenge to future food security. Towards addressing this, we isolated and characterized halotolerant bacteria from a Malaysian mangrove forest, and explored their effect on morpho-physiological and biochemical parameters of banana plantlets under salt stress. A total of 88 rhizobacterial and 16 endophytic bacterial isolates collected from the roots and rhizosphere of Rhizophora apiculata, Avicennia alba and Sonneratia alba, were found to tolerate up to 400 mM of sea salt. Based on best performance in multiple plant growth traits, three rhizobacterial strains RB1, RB3 and RB4 and three endophytic bacterial strains EB1, EB2 and EB3 were used for further analysis. The rhizobacterial strains were identified as Bacillus sp. and endophytic bacteria as Pseudomonas sp. based on 16 S rRNA gene sequence. SEM observation confirmed colonization of each strain on banana plantlet roots. When colonized plantlets were subjected to 90 mM salt and compared to uninoculated (control) and mock inoculated plants, improved plant growth was observed with each of the strains, especially with bacterial strains EB3 and RB3. Biochemical analysis of plantlets revealed that root colonization with EB3 and RB3 enhanced levels of plant chlorophyll (> 5-fold), carotenoid (> 2.85-fold) and proline (2.6-fold and 2.3-fold), while plantlets also showed reduced MDA content (0.45-fold and 0.51-fold), significantly reduced generation of ROS (0.23-fold and 0.47-fold) and lower levels of electrolyte leakage (0.77 and 0.51-fold). Antioxidant enzymes also showed enhanced activity with EB3 and RB3. Our results indicate that these halotolerant Bacillus and Pseudomonas strains from the mangrove have multifunctional plant growth promoting activity and can reduce salt stress in bananas. This data provides a reference for exploring halotolerant microbes from hypersaline environments to overcome salt stress in plants.
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23
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Pradhan S, Tyagi R, Sharma S. Combating biotic stresses in plants by synthetic microbial communities: Principles, applications, and challenges. J Appl Microbiol 2022; 133:2742-2759. [PMID: 36039728 DOI: 10.1111/jam.15799] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 08/24/2022] [Indexed: 11/29/2022]
Abstract
Presently, agriculture worldwide is facing the major challenge of feeding the increasing population sustainably. The conventional practices have not only failed to meet the projected needs, but also led to tremendous environmental consequences. Hence, to ensure a food-secure and environmentally sound future, the major thrust is on sustainable alternatives. Due to challenges associated with conventional means of application of biocontrol agents in the management of biotic stresses in agro-ecosystems, significant transformations in this context is needed. The crucial role played by soil microbiomes in efficiently and sustainably managing the agricultural production has unfolded a newer approach of rhizospheric engineering that shows immense promise in mitigating biotic stresses in an eco-friendly manner. The strategy of generating synthetic microbial communities (SynCom), by integrating omics approaches with traditional techniques of enumeration and in-depth analysis of plant-microbe interactions, is encouraging. The review discusses the significance of the rhizospheric microbiome in plant's fitness, and its manipulation for enhancing plant attributes. The focus of the review is to critically analyze the potential tools for the design and utilization of SynCom as a sustainable approach for rhizospheric engineering to ameliorate biotic stresses in plants. Further, based on the synthesis of reports in the area, we have put forth possible solutions to some of the critical issues that impair the large-scale application of SynComs in agriculture.
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Affiliation(s)
- Salila Pradhan
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi
| | - Rashi Tyagi
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi
| | - Shilpi Sharma
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi
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24
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Characterization of Siccibacter sp. Strain C2 a Novel Rhizobacterium that Enhances Tolerance of Barley to Salt Stress. Curr Microbiol 2022; 79:239. [PMID: 35794407 DOI: 10.1007/s00284-022-02930-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 06/09/2022] [Indexed: 11/03/2022]
Abstract
Plant growth promoting rhizobacteria (PGPR) arouse an increasing interest as an eco-friendly solution for improving crop tolerance to environmental stresses. In this study, we report the characterization of a novel halotolerant PGPR strain (named C2) identified in a screen of rhizospheric bacterial isolates from southeast of Tunisia. Phylogenetic analysis showed that strain C2 is most likely affiliated to the genus Siccibacter with Siccibacter turicensis as the closest species (98.19%). This strain was able to perform phosphate solubilization and production of indole acetic acid (IAA), siderophores, hydrogen cyanide (HCN), as well as different hydrolytic enzymes (proteases, amylases, cellulases, and lipases). The potential of strain C2 in enhancing salt stress tolerance of Hordeum vulgare was also investigated. Our greenhouse inoculation assays showed that strain C2 promotes barley growth in the presence of 400 mM NaCl by increasing biomass, root length, and chlorophyll contents. It has a positive effect on the photosynthetic efficiency, concomitantly with lower intercellular CO2 contents, compared to non-inoculated plants. Moreover, barley inoculation with strain C2 under salt stress, resulted in higher accumulation of proline and soluble sugars and alleviate the oxidative stress by decreasing hydrogen peroxide and malondialdehyde contents. Remarkably, this positive effect corroborates with a significant activation in the expression of a subset of barley stress responsive genes, including HVA1, HvDREB1, HvWRKY38 and HvP5CS. In summary, Siccibacter sp. strain C2 is able to enhance barley salt stress tolerance and should be leveraged in developing sustainable practices for cereal crop production.
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Yan Q, Li X, Xiao X, Chen J, Liu J, Lin C, Guan R, Wang D. Arbuscular mycorrhizal fungi improve the growth and drought tolerance of Cinnamomum migao by enhancing physio-biochemical responses. Ecol Evol 2022; 12:e9091. [PMID: 35845374 PMCID: PMC9273509 DOI: 10.1002/ece3.9091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 05/30/2022] [Accepted: 06/16/2022] [Indexed: 11/09/2022] Open
Abstract
Drought is the main limiting factor for plant growth in karst areas with a fragile ecological environment. Cinnamomum migao H.W. Li is an endemic medicinal woody plant present in the karst areas of southwestern China, and it is endangered due to poor drought tolerance. Arbuscular mycorrhizal fungi (AMF) are known to enhance the drought tolerance of plants. However, few studies have examined the contribution of AMF in improving the drought tolerance of C. migao seedlings. Therefore, we conducted a series of experiments to determine whether a single inoculation and coinoculation of AMF (Claroideoglomus lamellosum and Claroideoglomus etunicatum) enhanced the drought tolerance of C. migao. Furthermore, we compared the effects of single inoculation and coinoculation with different inoculum sizes (20, 40, 60, and 100 g; four replicates per treatment) on mycorrhizal colonization rate, plant growth, photosynthetic parameters, antioxidant enzyme activity, and malondialdehyde (MDA) and osmoregulatory substance contents. The results showed that compared with nonmycorrhizal plants, AMF colonization significantly improved plant growing status; net photosynthetic rate; superoxide dismutase, catalase, and peroxidase activities; and soluble sugar, soluble protein, and proline contents. Furthermore, AMF colonization increased relative water content and reduced MDA content in cells. These combined cumulative effects of AMF symbiosis ultimately enhanced the drought tolerance of seedlings and were closely related to the inoculum size. With an increase in inoculum size, the growth rate and drought tolerance of plants first increased and then decreased. The damage caused by drought stress could be reduced by inoculating 40-60 g of AMF, and the effect of coinoculation was significantly better than that of single inoculation at 60 g of AMF, while the effect was opposite at 40 g of AMF. Additionally, the interaction between AMF and inoculum sizes had a significant effect on drought tolerance. In conclusion, the inoculation of the AMF (Cl. lamellosum and Cl. etunicatum) improved photosynthesis, activated antioxidant enzymes, regulated cell osmotic state, and enhanced the drought tolerance of C. migao, enabling its growth in fragile ecological environments.
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Affiliation(s)
- Qiuxiao Yan
- Department of Ecology, College of Forestry Guizhou University Guiyang China.,The Key Laboratory of Chemistry for Natural Products of Guizhou Province and Chinese Academy of Sciences Guiyang China.,State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Guiyang China
| | - Xiangying Li
- Institute of New Rural Development Guizhou University Guiyang China
| | - Xuefeng Xiao
- Department of Ecology, College of Forestry Guizhou University Guiyang China
| | - Jingzhong Chen
- Department of Ecology, College of Forestry Guizhou University Guiyang China
| | - Jiming Liu
- Department of Ecology, College of Forestry Guizhou University Guiyang China
| | - Changhu Lin
- Department of Labor Health and Environmental Hygiene, School of Public Health Guizhou Medical University Guiyang China
| | - Ruiting Guan
- Department of Ecology, College of Forestry Guizhou University Guiyang China
| | - Daoping Wang
- The Key Laboratory of Chemistry for Natural Products of Guizhou Province and Chinese Academy of Sciences Guiyang China.,State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Guiyang China
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26
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Swiontek Brzezinska M, Świątczak J, Wojciechowska A, Burkowska-But A, Kalwasińska A. Consortium of plant growth-promoting rhizobacteria enhances oilseed rape (Brassica napus L.) growth under normal and saline conditions. Arch Microbiol 2022; 204:393. [PMID: 35704071 DOI: 10.1007/s00203-022-03018-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 02/15/2022] [Accepted: 05/23/2022] [Indexed: 11/02/2022]
Abstract
A preparation development, which stimulates plant growth under normal and saline conditions, and protects against fungal infections, would increase crop yields and reduce damage in agriculture. This study was conducted using bacterial isolates from rape rhizosphere as a plant growth promoter and an alternative to chemical fertilizers. Three from fifty bacterial isolates: B14 (Pseudomonas sp.), B16 (Sphingobacterium sp.), and B19 (Microbacterium sp.) showed the best in vitro plant growth-promoting (PGP) characteristics. B14 strain had the best antifungal activity against phytopathogens inhibiting growth of B. cinerea, C. acutatum, and P. lingam. Moreover, B14, B16 and B19 isolates coded for several genes involved in PGP activities, aimed at improving nutrient availability, resistance to abiotic stress, and fungal pathogen suppression. Microbial consortium (B14, B16, and B19) had the best effect on rape growth, significantly increasing number of live leaves, compared to the untreated control and single inoculant treatments. Moreover, the consortium induced significant increase in shoots length and chlorophyll content in comparison to Pseudomonas sp. B14 and Microbacterium sp. B19. The consortium also induced plants tolerance to salt stress. The genomic information as well as the observed traits, and beneficial attributes towards rape, make the rhizobacterial consortium an ideal candidate for further development as biofertilizers.
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Affiliation(s)
- Maria Swiontek Brzezinska
- Department of Environmental Microbiology and Biotechnology, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Torun, Gagarina 11, 87100, Torun, Poland.
| | - Joanna Świątczak
- Department of Environmental Microbiology and Biotechnology, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Torun, Gagarina 11, 87100, Torun, Poland
| | - Anna Wojciechowska
- Department of Geobotany and Landscape Planning, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Torun, Gagarina 11, 87 100, Torun, Poland
| | - Aleksandra Burkowska-But
- Department of Environmental Microbiology and Biotechnology, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Torun, Gagarina 11, 87100, Torun, Poland
| | - Agnieszka Kalwasińska
- Department of Environmental Microbiology and Biotechnology, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Torun, Gagarina 11, 87100, Torun, Poland
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Effects of Mercury Contamination on Microbial Diversity of Different Kinds of Soil. Microorganisms 2022; 10:microorganisms10050977. [PMID: 35630421 PMCID: PMC9144551 DOI: 10.3390/microorganisms10050977] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 04/29/2022] [Accepted: 05/04/2022] [Indexed: 11/17/2022] Open
Abstract
Soil microorganisms promote the recovery of contaminated soil by influencing the cyclic transformation of various substances. In this study, we investigated the impact of mercury pollution on the structure, composition, and main populations of soil microbial communities using a high-throughput sequencing method and observed that mercury pollution significantly influenced the diversity, structure, and distribution pattern of microbial communities. Furthermore, during mercury pollution, the Shannon and Chao indices decreased for the bacterial communities and increased for the fungal communities. Mercury pollution mainly reduced the relative abundances of Proteobacteria (16.2−30.6%), Actinomycetes (24.7−40.8%), and other dominant bacterial phyla. The relative abundance of Ascomycota decreased by 17.4% and 16.7% in alkaline and neutral soils, respectively, whereas the relative abundance of unclassified_k_Fungi increased by 26.1% and 28.6%, respectively. In acidic soil, Ascomycota increased by 106.3% and unclassified_k_Fungi decreased by 71.2%. The results of redundancy and correlation analyses suggested that soil microbial diversity was significantly correlated with soil properties such as pH, cation exchange capacity, soil organic carbon, and total nitrogen (p < 0.05) under different treatments. Our findings highlight the impact of Hg pollution on soil microbial communities, thereby providing a theoretical foundation for the bioremediation of soil Hg pollution.
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28
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Srivastava AK, Das AK, Jagannadham PTK, Bora P, Ansari FA, Bhate R. Bioprospecting Microbiome for Soil and Plant Health Management Amidst Huanglongbing Threat in Citrus: A Review. FRONTIERS IN PLANT SCIENCE 2022; 13:858842. [PMID: 35557712 PMCID: PMC9088001 DOI: 10.3389/fpls.2022.858842] [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: 01/20/2022] [Accepted: 03/21/2022] [Indexed: 06/15/2023]
Abstract
Microorganisms have dynamic and complex interactions with their hosts. Diverse microbial communities residing near, on, and within the plants, called phytobiome, are an essential part of plant health and productivity. Exploiting citrus-associated microbiomes represents a scientific approach toward sustained and environment-friendly module of citrus production, though periodically exposed to several threats, with Huanglongbing (HLB) predominantly being most influential. Exploring the composition and function of the citrus microbiome, and possible microbial redesigning under HLB disease pressure has sparked renewed interest in recent times. A concise account of various achievements in understanding the citrus-associated microbiome, in various niche environments viz., rhizosphere, phyllosphere, endosphere, and core microbiota alongside their functional attributes has been thoroughly reviewed and presented. Efforts were also made to analyze the actual role of the citrus microbiome in soil fertility and resilience, interaction with and suppression of invading pathogens along with native microbial communities and their consequences thereupon. Despite the desired potential of the citrus microbiota to counter different pathogenic diseases, utilizing the citrus microbiome for beneficial applications at the field level is yet to be translated as a commercial product. We anticipate that advancement in multiomics technologies, high-throughput sequencing and culturing, genome editing tools, artificial intelligence, and microbial consortia will provide some exciting avenues for citrus microbiome research and microbial manipulation to improve the health and productivity of citrus plants.
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Affiliation(s)
- Anoop Kumar Srivastava
- Indian Council of Agricultural Research (ICAR)-Central Citrus Research Institute, Nagpur, India
| | - Ashis Kumar Das
- Indian Council of Agricultural Research (ICAR)-Central Citrus Research Institute, Nagpur, India
| | | | - Popy Bora
- Department of Plant Pathology, Assam Agricultural University, Jorhat, India
| | - Firoz Ahmad Ansari
- Indian Council of Agricultural Research (ICAR)-Central Citrus Research Institute, Nagpur, India
| | - Ruchi Bhate
- Indian Council of Agricultural Research (ICAR)-Central Citrus Research Institute, Nagpur, India
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29
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Franzino T, Boubakri H, Cernava T, Abrouk D, Achouak W, Reverchon S, Nasser W, Haichar FEZ. Implications of carbon catabolite repression for plant-microbe interactions. PLANT COMMUNICATIONS 2022; 3:100272. [PMID: 35529946 PMCID: PMC9073323 DOI: 10.1016/j.xplc.2021.100272] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 11/17/2021] [Accepted: 12/27/2021] [Indexed: 06/14/2023]
Abstract
Carbon catabolite repression (CCR) plays a key role in many physiological and adaptive responses in a broad range of microorganisms that are commonly associated with eukaryotic hosts. When a mixture of different carbon sources is available, CCR, a global regulatory mechanism, inhibits the expression and activity of cellular processes associated with utilization of secondary carbon sources in the presence of the preferred carbon source. CCR is known to be executed by completely different mechanisms in different bacteria, yeast, and fungi. In addition to regulating catabolic genes, CCR also appears to play a key role in the expression of genes involved in plant-microbe interactions. Here, we present a detailed overview of CCR mechanisms in various bacteria. We highlight the role of CCR in beneficial as well as deleterious plant-microbe interactions based on the available literature. In addition, we explore the global distribution of known regulatory mechanisms within bacterial genomes retrieved from public repositories and within metatranscriptomes obtained from different plant rhizospheres. By integrating the available literature and performing targeted meta-analyses, we argue that CCR-regulated substrate use preferences of microorganisms should be considered an important trait involved in prevailing plant-microbe interactions.
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Affiliation(s)
- Theophile Franzino
- INSA-Lyon, Université Claude Bernard Lyon 1, CNRS, UMR5240, Microbiologie, Adaptation, Pathogénie, Université Lyon, 10 rue Raphaël Dubois, 69622 Villeurbanne, France
| | - Hasna Boubakri
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR Écologie Microbienne, 69622 Villeurbanne, France
| | - Tomislav Cernava
- Institute of Environmental Biotechnology, Graz University of Technology, Petersgasse 12/I, Graz 8010, Austria
| | - Danis Abrouk
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR Écologie Microbienne, 69622 Villeurbanne, France
| | - Wafa Achouak
- Aix Marseille Université, CEA, CNRS, BIAM, Lab Microbial Ecology of the Rhizosphere (LEMiRE), 13108 Saint-Paul-Lez-Durance, France
| | - Sylvie Reverchon
- INSA-Lyon, Université Claude Bernard Lyon 1, CNRS, UMR5240, Microbiologie, Adaptation, Pathogénie, Université Lyon, 10 rue Raphaël Dubois, 69622 Villeurbanne, France
| | - William Nasser
- INSA-Lyon, Université Claude Bernard Lyon 1, CNRS, UMR5240, Microbiologie, Adaptation, Pathogénie, Université Lyon, 10 rue Raphaël Dubois, 69622 Villeurbanne, France
| | - Feth el Zahar Haichar
- INSA-Lyon, Université Claude Bernard Lyon 1, CNRS, UMR5240, Microbiologie, Adaptation, Pathogénie, Université Lyon, 10 rue Raphaël Dubois, 69622 Villeurbanne, France
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Bacillus velezensis stimulates resident rhizosphere Pseudomonas stutzeri for plant health through metabolic interactions. THE ISME JOURNAL 2022; 16:774-787. [PMID: 34593997 PMCID: PMC8483172 DOI: 10.1038/s41396-021-01125-3] [Citation(s) in RCA: 110] [Impact Index Per Article: 55.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 09/16/2021] [Accepted: 09/20/2021] [Indexed: 02/08/2023]
Abstract
Trophic interactions play a central role in driving microbial community assembly and function. In gut or soil ecosystems, successful inoculants are always facilitated by efficient colonization; however, the metabolite exchanges between inoculants and resident bacteria are rarely studied, particularly in the rhizosphere. Here, we used bioinformatic, genetic, transcriptomic, and metabonomic analyses to uncover syntrophic cooperation between inoculant (Bacillus velezensis SQR9) and plant-beneficial indigenous Pseudomonas stutzeri in the cucumber rhizosphere. We found that the synergistic interaction of these two species is highly environmental dependent, the emergence of syntrophic cooperation was only evident in a static nutrient-rich niche, such as pellicle biofilm in addition to the rhizosphere. Our results identified branched-chain amino acids (BCAAs) biosynthesis pathways are involved in syntrophic cooperation. Genome-scale metabolic modeling and metabolic profiling also demonstrated metabolic facilitation among the bacterial strains. In addition, biofilm matrix components from Bacillus were essential for the interaction. Importantly, the two-species consortium promoted plant growth and helped plants alleviate salt stress. In summary, we propose a mechanism in which synergic interactions between a biocontrol bacterium and a partner species promote plant health.
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Chaparro-Encinas LA, Parra-Cota FI, Cruz-Mendívil A, Santoyo G, Peña-Cabriales JJ, Castro-Espinoza L, de Los Santos-Villalobos S. Transcriptional regulation of cell growth and reprogramming of systemic response in wheat (Triticum turgidum subsp. durum) seedlings by Bacillus paralicheniformis TRQ65. PLANTA 2022; 255:56. [PMID: 35106645 DOI: 10.1007/s00425-022-03837-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 01/23/2022] [Indexed: 06/14/2023]
Abstract
Bacillus paralicheniformis TRQ65 reprograms the gene expression patterns associated with systemic response to potentially facilitate its colonization and stimulate cell growth and plant biomass. Plant growth-promoting rhizobacteria (PGPR) carry out numerous mechanisms that enhance growth in seedlings, such as nutrient solubilization, phytohormone production, biocontrol activity, and regulation of induced systemic resistance (ISR) and acquired systemic resistance (ASR). Bacillus paralicheniformis TRQ65 is a biological and plant growth-promoting bacterium isolated from wheat (Triticum turgidum subsp. durum) rhizosphere. In this study, we performed a transcriptomic analysis of wheat seedlings inoculated with the native rhizobacterium Bacillus paralicheniformis TRQ65 (1 × 107 cells∙g -1 of soil) at early development stages (GS15). A morphometrical assay was carried out to confirm growth promotion and after the cultivation period, TRQ65 was re-isolated to define inoculum persistence. Inoculated seedlings showed a significant (P < 0.05) increase in shoot length (93.48%) and dry weight in both shoot (117.02%) and root (48.33%) tissues; also, the strain persisted in the soil at 1.4 × 107 UFC∙g-1 of soil. A total of 228 differentially expressed genes (DEGs) (FDR < 0.05 and |log2 fold change|≥ 1.3) were observed in response to TRQ65 inoculation, of which 185 were down-regulated and 43 were up-regulated. The transcriptional patterns were characterized by the regulation of multidimensional cell growth (ROS, Ca+2 channel, and NADPH oxidases activity), suppression of defense mechanism (PR proteins, PDFs, ROS, transcription factors), induction of central stimuli receptors (RALF, WAK, MAPK), carbohydrate metabolism (invertase activity) and phytohormone-related transport (ABCG transporter and AAAP). These results suggest that B. paralicheniformis TRQ65 is a promising bioinoculant agent for increasing wheat growth and development by reprogramming ISR and ASR simultaneously, suppressing defense mechanisms and inducing central stimuli response.
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Affiliation(s)
- Luis A Chaparro-Encinas
- Instituto Tecnológico de Sonora, 5 de febrero 818 Sur, C.P. 85000, Col. Centro, Ciudad Obregón, Sonora, México
- Universidad Autónoma Agraria Antonio Narro (UAAAN) Unidad Laguna, Periférico Raúl López Sánchez, Valle Verde, 27054, Torreón, Coahuila, México
| | - Fannie I Parra-Cota
- Campo Experimental Norman E. Borlaug-CIRNO. Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias (INIFAP), Norman E. Borlaug Km. 12, CP 85000, Valle del Yaqui, Ciudad Obregón, Sonora, México
| | - Abraham Cruz-Mendívil
- Cátedras CONACYT, Instituto Politécnico Nacional, Centro Interdisciplinario de Investigación Para el Desarrollo Integral Regional (CIIDIR) Unidad Sinaloa, Guasave, Sinaloa, México
| | - Gustavo Santoyo
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, México
| | - Juan J Peña-Cabriales
- Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional Campus Guanajuato, Irapuato Guanajuato, México
| | - Luciano Castro-Espinoza
- Instituto Tecnológico de Sonora, 5 de febrero 818 Sur, C.P. 85000, Col. Centro, Ciudad Obregón, Sonora, México
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Abstract
Some Bacillus species, such as B. velezensis, are important members of the plant-associated microbiome, conferring protection against phytopathogens. However, our knowledge about multitrophic interactions determining the ecological fitness of these biocontrol bacteria in the competitive rhizosphere niche is still limited. Here, we investigated molecular mechanisms underlying interactions between B. velezensis and Pseudomonas as a soil-dwelling competitor. Upon their contact-independent in vitro confrontation, a multifaceted macroscopic outcome was observed and characterized by Bacillus growth inhibition, white line formation in the interaction zone, and enhanced motility. We correlated these phenotypes with the production of bioactive secondary metabolites and identified specific lipopeptides as key compounds involved in the interference interaction and motile response. Bacillus mobilizes its lipopeptide surfactin not only to enhance motility but also to act as a chemical trap to reduce the toxicity of lipopeptides formed by Pseudomonas. We demonstrated the relevance of these unsuspected roles of lipopeptides in the context of competitive tomato root colonization by the two bacterial genera. IMPORTANCE Plant-associated Bacillus velezensis and Pseudomonas spp. represent excellent model species as strong producers of bioactive metabolites involved in phytopathogen inhibition and the elicitation of plant immunity. However, the ecological role of these metabolites during microbial interspecies interactions and the way their expression may be modulated under naturally competitive soil conditions has been poorly investigated. Through this work, we report various phenotypic outcomes from the interactions between B. velezensis and 10 Pseudomonas strains used as competitors and correlate them with the production of specific metabolites called lipopeptides from both species. More precisely, Bacillus overproduces surfactin to enhance motility, which also, by acting as a chemical trap, reduces the toxicity of other lipopeptides formed by Pseudomonas. Based on data from interspecies competition on plant roots, we assume this would allow Bacillus to gain fitness and persistence in its natural rhizosphere niche. The discovery of new ecological functions for Bacillus and Pseudomonas secondary metabolites is crucial to rationally design compatible consortia, more efficient than single-species inoculants, to promote plant health and growth by fighting economically important pathogens in sustainable agriculture.
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Panichikkal J, Jose A, Sreekumaran S, Ashokan AK, Baby CS, Krishnankutty RE. Biofilm and Biocontrol Modulation of Paenibacillus sp. CCB36 by Supplementation with Zinc Oxide Nanoparticles and Chitosan Nanoparticles. Appl Biochem Biotechnol 2021; 194:1606-1620. [PMID: 34822058 DOI: 10.1007/s12010-021-03710-w] [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: 06/07/2021] [Accepted: 10/08/2021] [Indexed: 11/28/2022]
Abstract
Endophytic bacteria with multi-trait plant beneficial features have applications to enhance agricultural productivity by supporting the plant growth, yield, and disease resistance. In this study, Paenibacillus sp. CCB36 was isolated from the rhizome of Curcuma caesia Roxb., and its biofilm formation and antifungal properties have been evaluated in the presence of nanoparticles. Chitosan nanoparticles (CNPs) were synthesized and characterized by UV-visible spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, high-resolution-transmission electron microscopic (HR-TEM) analysis, scanning electron microscopic (SEM) analysis, and dynamic light scattering (DLS). The effect of zinc oxide nanoparticles (ZnONPs) and CNPs on biofilm formation of Paenibacillus sp. CCB36 was evaluated by tissue culture plate assay. ZnONPs reduced its biofilm formation and was found to get modulated in the presence of CNPs as revealed by atomic force microscopy (AFM). Hence, CNPs were selected for further studies. Interestingly, biocontrol property of Paenibacillus sp. CCB36 against Rhizoctonia solani was also found to get enhanced when supplemented with chitosan nanoparticles. The results of the study indicate application of nanoparticles to improve colonization and active functioning of endophytic bacteria which can have significant application in agriculture.
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Affiliation(s)
- Jishma Panichikkal
- School of Biosciences, Mahatma Gandhi University, PD Hills (PO), Kottayam, Kerala, India, 686 560
| | - Ashitha Jose
- School of Biosciences, Mahatma Gandhi University, PD Hills (PO), Kottayam, Kerala, India, 686 560
| | - Sreejith Sreekumaran
- School of Biosciences, Mahatma Gandhi University, PD Hills (PO), Kottayam, Kerala, India, 686 560
| | | | - Cimmiya Susan Baby
- Department of Biosciences, M.E.S. College, Marampally (PO), Aluva, Kerala, India, 683 107
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Comeau D, Balthazar C, Novinscak A, Bouhamdani N, Joly DL, Filion M. Interactions Between Bacillus Spp., Pseudomonas Spp. and Cannabis sativa Promote Plant Growth. Front Microbiol 2021; 12:715758. [PMID: 34616381 PMCID: PMC8488376 DOI: 10.3389/fmicb.2021.715758] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 08/24/2021] [Indexed: 01/04/2023] Open
Abstract
Plant growth-promoting rhizobacteria (PGPR) deploy several mechanisms to improve plant health, growth and yield. The aim of this study was to evaluate the efficacy of two Pseudomonas spp. strains and three Bacillus spp. strains used as single treatments and in consortia to improve the yield of Cannabis sativa and characterize the impact of these treatments on the diversity, structure and functions of the rhizosphere microbiome. Herein, we demonstrate a significant C. sativa yield increase up to 70% when inoculated with three different Pseudomonas spp./Bacillus spp. consortia but not with single inoculation treatments. This growth-promoting effect was observed in two different commercial soil substrates commonly used to grow cannabis: Promix and Canna coco. Marker-based genomic analysis highlighted Bacillus spp. as the main modulator of the rhizosphere microbiome diversity and Pseudomonas spp. as being strongly associated with plant growth promotion. We describe an increase abundance of predicted PGPR metabolic pathways linked with growth-promoting interactions in C. sativa.
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Affiliation(s)
- Dominique Comeau
- Department of Biology, University of Moncton, Moncton, NB, Canada
| | - Carole Balthazar
- Department of Biology, University of Moncton, Moncton, NB, Canada
| | - Amy Novinscak
- Research and Development Centre, Agriculture and Agri-Food Canada, Agassiz, BC, Canada
| | - Nadia Bouhamdani
- Department of Chemistry and Biochemistry, University of Moncton, Moncton, NB, Canada
| | - David L Joly
- Department of Biology, University of Moncton, Moncton, NB, Canada
| | - Martin Filion
- Research and Development Centre, Agriculture and Agri-Food Canada, Saint-Jean-sur-Richelieu, QC, Canada
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Salix purpurea and Eleocharis obtusa Rhizospheres Harbor a Diverse Rhizospheric Bacterial Community Characterized by Hydrocarbons Degradation Potentials and Plant Growth-Promoting Properties. PLANTS 2021; 10:plants10101987. [PMID: 34685796 PMCID: PMC8538330 DOI: 10.3390/plants10101987] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/14/2021] [Accepted: 09/17/2021] [Indexed: 11/22/2022]
Abstract
Phytoremediation, a method of phytomanagement using the plant holobiont to clean up polluted soils, is particularly effective for degrading organic pollutants. However, the respective contributions of host plants and their associated microbiota within the holobiont to the efficiency of phytoremediation is poorly understood. The identification of plant-associated bacteria capable of efficiently utilizing these compounds as a carbon source while stimulating plant-growth is a keystone for phytomanagement engineering. In this study, we sampled the rhizosphere and the surrounding bulk soil of Salixpurpurea and Eleocharis obusta from the site of a former petrochemical plant in Varennes, QC, Canada. Our objectives were to: (i) isolate and identify indigenous bacteria inhabiting these biotopes; (ii) assess the ability of isolated bacteria to utilize alkanes and polycyclic aromatic hydrocarbons (PAHS) as the sole carbon source, and (iii) determine the plant growth-promoting (PGP) potential of the isolates using five key traits. A total of 438 morphologically different bacterial isolates were obtained, purified, preserved and identified through PCR and 16S rRNA gene sequencing. Identified isolates represent 62 genera. Approximately, 32% of bacterial isolates were able to utilize all five different hydrocarbons compounds. Additionally, 5% of tested isolates belonging to genera Pseudomonas, Acinetobacter, Serratia, Klebsiella, Microbacterium, Bacillus and Stenotrophomonas possessed all five of the tested PGP functional traits. This culture collection of diverse, petroleum-hydrocarbon degrading bacteria, with multiple PGP traits, represents a valuable resource for future use in environmental bio- and phyto-technology applications.
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Lu S, He R, Zhao D, Zeng J, Huang X, Li K, Yu Z, Wu QL. Effects of shading levels on the composition and co-occurrence patterns of bacterioplankton and epibiotic bacterial communities of Cabomba caroliniana. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 785:147286. [PMID: 33932676 DOI: 10.1016/j.scitotenv.2021.147286] [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: 11/11/2020] [Revised: 03/31/2021] [Accepted: 04/17/2021] [Indexed: 06/12/2023]
Abstract
Epibiotic bacterial community colonized on the plant leaf plays important roles in promoting plant growth and nutrient absorption, but is sensitive to environmental changes. As one of the most important environmental factors affecting the growth of plants and photosynthetic microorganisms, light may affect the diversity, composition, and interactions of the epibiotic bacterial community. Submerged plants in the aquatic ecosystem may be more sensitive to light intensity variations compared to the terrestrial plants since they usually receive less light. However, the effects of light on the interactions between the submerged plants and their epibiotic microbial communities remain uncertain. Here we used the 16S rRNA gene high-throughput sequencing to investigate the diversity and composition of the bacterioplankton and epibiotic bacterial communities of the Cabomba caroliniana under four different shading levels. A total of 24 water and leaf samples were collected from the experimental microcosms near Lake Taihu. We found the epibiotic bacterial community possessed a higher diversity than that of the bacterioplankton community, although the alpha diversity of the bacterioplankton community was more susceptible to different levels of shading. SourceTracker analysis revealed that with the increase of shading, the colonization of bacterioplankton to epibiotic bacteria decreased. Network analysis showed that the bacterial community network at 50% shading level had the lowest modularity and highest clustering coefficient compared to the bacterial community networks of other shading levels. Our findings provided new understandings of the effects of different light intensities on the epibiotic bacterial communities of submerged macrophytes.
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Affiliation(s)
- Shijie Lu
- Joint International Research Laboratory of Global Change and Water Cycle, State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China
| | - Rujia He
- Joint International Research Laboratory of Global Change and Water Cycle, State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China; State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, East Beijing Road 73, Nanjing 210008, China
| | - Dayong Zhao
- Joint International Research Laboratory of Global Change and Water Cycle, State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China
| | - Jin Zeng
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, East Beijing Road 73, Nanjing 210008, China.
| | - Xiaolong Huang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, East Beijing Road 73, Nanjing 210008, China
| | - Kuanyi Li
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, East Beijing Road 73, Nanjing 210008, China
| | - Zhongbo Yu
- Joint International Research Laboratory of Global Change and Water Cycle, State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China
| | - Qinglong L Wu
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, East Beijing Road 73, Nanjing 210008, China; Sino-Danish Centre for Education and Research, University of Chinese Academy of Sciences, Beijing, China
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Hinsu AT, Panchal KJ, Pandit RJ, Koringa PG, Kothari RK. Characterizing rhizosphere microbiota of peanut (Arachis hypogaea L.) from pre-sowing to post-harvest of crop under field conditions. Sci Rep 2021; 11:17457. [PMID: 34465845 PMCID: PMC8408145 DOI: 10.1038/s41598-021-97071-3] [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: 05/12/2021] [Accepted: 08/10/2021] [Indexed: 01/04/2023] Open
Abstract
The rhizosphere, a narrow zone of soil near plant roots, is a hot spot for microbial activity. Rhizosphere microbiota directly or indirectly benefit plants by supplementing nutrients, producing beneficial chemicals, or suppressing pathogens. Plants attract and modulate bacteria within the rhizosphere by releasing exudates. Plants also tend to select the rhizosphere microbiota based on their needs; a phenomenon termed as “rhizosphere effect”. In this study, we characterized the rhizosphere microbiota of peanut plants across the crop development cycle from pre-sowing of seeds to post-harvest of crop under field conditions. The rhizosphere and bulk soil samples from different crop developmental stages were also compared. The composition of bulk soil microbiota resembled microbiota of pre-sowing and post-harvest soil and was markedly different from rhizosphere soil samples. Rhizosphere samples were enriched with multiple organisms mostly from the Proteobacteria, Firmicutes and Bacteroidota phyla. Differences in diversity were observed among the rhizosphere samples but not in bulk soil across different crop development stages. Pseudomonas_M indica was highly enriched during the germination of seeds. Furthermore, Plant Growth Promoting (PGP) bacteria like Bacillus were enriched during the middle stages of crop development but there was a decline in PGP organisms in the matured crop stage. We also observed a significant association of pH and Electrical Conductivity (EC) with the profiles of microbial community. Overall, this study portrayed the changes in rhizosphere microbiota of peanut during different developmental stages of crop and may help to design stage specific bio-strategies such as bio-fertilizer to improve crop yield.
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Affiliation(s)
- Ankit T Hinsu
- Department of Biosciences, Saurashtra University, Rajkot, 360005, India.,Department of Animal Biotechnology, College of Veterinary Sciences & A.H., Anand Agricultural University, Anand, 388001, India
| | - Ketankumar J Panchal
- Department of Animal Biotechnology, College of Veterinary Sciences & A.H., Anand Agricultural University, Anand, 388001, India
| | - Ramesh J Pandit
- Department of Animal Biotechnology, College of Veterinary Sciences & A.H., Anand Agricultural University, Anand, 388001, India
| | - Prakash G Koringa
- Department of Animal Biotechnology, College of Veterinary Sciences & A.H., Anand Agricultural University, Anand, 388001, India
| | - Ramesh K Kothari
- Department of Biosciences, Saurashtra University, Rajkot, 360005, India.
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Fiodor A, Singh S, Pranaw K. The Contrivance of Plant Growth Promoting Microbes to Mitigate Climate Change Impact in Agriculture. Microorganisms 2021; 9:1841. [PMID: 34576736 PMCID: PMC8472176 DOI: 10.3390/microorganisms9091841] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/14/2021] [Accepted: 08/27/2021] [Indexed: 01/07/2023] Open
Abstract
Combating the consequences of climate change is extremely important and critical in the context of feeding the world's population. Crop simulation models have been extensively studied recently to investigate the impact of climate change on agricultural productivity and food security. Drought and salinity are major environmental stresses that cause changes in the physiological, biochemical, and molecular processes in plants, resulting in significant crop productivity losses. Excessive use of chemicals has become a severe threat to human health and the environment. The use of beneficial microorganisms is an environmentally friendly method of increasing crop yield under environmental stress conditions. These microbes enhance plant growth through various mechanisms such as production of hormones, ACC deaminase, VOCs and EPS, and modulate hormone synthesis and other metabolites in plants. This review aims to decipher the effect of plant growth promoting bacteria (PGPB) on plant health under abiotic soil stresses associated with global climate change (viz., drought and salinity). The application of stress-resistant PGPB may not only help in the combating the effects of abiotic stressors, but also lead to mitigation of climate change. More thorough molecular level studies are needed in the future to assess their cumulative influence on plant development.
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Affiliation(s)
- Angelika Fiodor
- Department of Environmental Microbiology and Biotechnology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland;
| | - Surender Singh
- Department of Microbiology, Central University of Haryana, Mahendergarh 123031, Haryana, India;
| | - Kumar Pranaw
- Department of Environmental Microbiology and Biotechnology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland;
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Bhagat N, Raghav M, Dubey S, Bedi N. Bacterial Exopolysaccharides: Insight into Their Role in Plant Abiotic Stress Tolerance. J Microbiol Biotechnol 2021; 31:1045-1059. [PMID: 34226402 PMCID: PMC9706007 DOI: 10.4014/jmb.2105.05009] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/17/2021] [Accepted: 06/17/2021] [Indexed: 12/15/2022]
Abstract
Various abiotic stressors like drought, salinity, temperature, and heavy metals are major environmental stresses that affect agricultural productivity and crop yields all over the world. Continuous changes in climatic conditions put selective pressure on the microbial ecosystem to produce exopolysaccharides. Apart from soil aggregation, exopolysaccharide (EPS) production also helps in increasing water permeability, nutrient uptake by roots, soil stability, soil fertility, plant biomass, chlorophyll content, root and shoot length, and surface area of leaves while also helping maintain metabolic and physiological activities during drought stress. EPS-producing microbes can impart salt tolerance to plants by binding to sodium ions in the soil and preventing these ions from reaching the stem, thereby decreasing sodium absorption from the soil and increasing nutrient uptake by the roots. Biofilm formation in high-salinity soils increases cell viability, enhances soil fertility, and promotes plant growth and development. The third environmental stressor is presence of heavy metals in the soil due to improper industrial waste disposal practices that are toxic for plants. EPS production by soil bacteria can result in the biomineralization of metal ions, thereby imparting metal stress tolerance to plants. Finally, high temperatures can also affect agricultural productivity by decreasing plant metabolism, seedling growth, and seed germination. The present review discusses the role of exopolysaccharide-producing plant growth-promoting bacteria in modulating plant growth and development in plants and alleviating extreme abiotic stress condition. The review suggests exploring the potential of EPS-producing bacteria for multiple abiotic stress management strategies.
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Affiliation(s)
- Neeta Bhagat
- Amity Institute of Biotechnology, Amity University Uttar Pradesh, Sector 125, Noida 201301, India,Corresponding author Phone: +7042420808 E-mail:
| | - Meenu Raghav
- Amity Institute of Biotechnology, Amity University Uttar Pradesh, Sector 125, Noida 201301, India
| | - Sonali Dubey
- Amity Institute of Biotechnology, Amity University Uttar Pradesh, Sector 125, Noida 201301, India
| | - Namita Bedi
- Amity Institute of Biotechnology, Amity University Uttar Pradesh, Sector 125, Noida 201301, India
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Effects of Root-Colonizing Fluorescent Pseudomonas Strains on Arabidopsis Resistance to a Pathogen and an Herbivore. Appl Environ Microbiol 2021; 87:e0283120. [PMID: 33893115 DOI: 10.1128/aem.02831-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Rhizobacteria in the genus Pseudomonas can enhance plant resistance to a range of pathogens and herbivores. However, resistance to these different classes of plant antagonists is mediated by different molecular mechanisms, and the extent to which induced systemic resistance by Pseudomonas can simultaneously protect plants against both pathogens and herbivores remains unclear. We screened 12 root-colonizing Pseudomonas strains to assess their ability to induce resistance in Arabidopsis thaliana against a foliar pathogen (Pseudomonas syringae DC3000) and a chewing herbivore (Spodoptera littoralis). None of our 12 strains increased plant resistance against herbivory; however, four strains enhanced pathogen resistance, and one of these (Pseudomonas strain P97-38) also made plants more susceptible to herbivory. Phytohormone analyses revealed stronger salicylic acid induction in plants colonized by P97-38 (versus controls) following subsequent pathogen infection but weaker induction of jasmonic acid (JA)-mediated defenses following herbivory. We found no effects of P97-38 inoculation on herbivore-relevant nutrients such as sugars and protein, suggesting that the observed enhancement of susceptibility to S. littoralis is due to effects on plant defense chemistry rather than nutrition. These findings suggest that Pseudomonas strains that enhance plant resistance to pathogens may have neutral or negative effects on resistance to herbivores and provide insight into potential mechanisms associated with effects on different classes of plant antagonists. Improved understanding of these effects has potentially important implications for the use of rhizobacteria inoculation in agriculture. IMPORTANCE Plant-associated microbes have significant potential to enhance agricultural production, for example, by enhancing plant resistance to pathogens and pests. Efforts to identify beneficial microbial strains typically focus on a narrow range of desirable plant traits; however, microbial symbionts can have complex effects on plant phenotypes, including susceptibility and resistance to different classes of plant antagonists. We examined the effects of 12 strains of Pseudomonas rhizobacteria on plant (Arabidopsis) resistance to a lepidopteran herbivore and a foliar pathogen. None of our strains increased plant resistance against herbivory; however, four strains enhanced pathogen resistance, and one of these made plants more susceptible to herbivory (likely via effects on plant defense chemistry). These findings indicate that microbial strains that enhance plant resistance to pathogens can have neutral or negative effects on resistance to herbivores, highlighting potential pitfalls in the application of beneficial rhizobacteria as biocontrol agents.
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Bhatia R, Gulati D, Sethi G. Biofilms and nanoparticles: applications in agriculture. Folia Microbiol (Praha) 2021; 66:159-170. [PMID: 33528768 DOI: 10.1007/s12223-021-00851-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 01/04/2021] [Indexed: 02/04/2023]
Abstract
A profound need to explore eco-friendly methods to practice sustainable agriculture leads to the research and exploration of plant growth-promoting rhizobacteria (PGPRs). Biofilms are assemblages of microbial communities within a self-secreted exopolymeric matrix, adhering to different biotic and abiotic surfaces and performing a variety of desired and undesired functions. Biofilm formation by PGPRs is governed by effective root colonization of the host plant in providing plant growth promotion and stress management. Biofilms can also provide a suitable environment for the synthesis and entrapment of nanoparticles. Together, nanoparticles and PGPRs may contribute towards biocontrol and crop management. This review discusses the significance of biofilms in agriculture and their confluence with different types of nanoparticles for plant protection and improved crop production.
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Affiliation(s)
- Ranjana Bhatia
- Department of Biotechnology, University Institute of Engineering and Technology, Panjab University, Chandigarh, 160014, India.
| | - Divij Gulati
- Department of Biotechnology, University Institute of Engineering and Technology, Panjab University, Chandigarh, 160014, India
| | - Gavin Sethi
- Department of Biotechnology, University Institute of Engineering and Technology, Panjab University, Chandigarh, 160014, India
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Halim MA, Rahman MM, Megharaj M, Naidu R. Cadmium Immobilization in the Rhizosphere and Plant Cellular Detoxification: Role of Plant-Growth-Promoting Rhizobacteria as a Sustainable Solution. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:13497-13529. [PMID: 33170689 DOI: 10.1021/acs.jafc.0c04579] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Food is the major cadmium (Cd)-exposure pathway from agricultural soils to humans and other living entities and must be reduced in an effective way. A plant can select beneficial microbes, like plant-growth-promoting rhizobacteria (PGPR), depending upon the nature of root exudates in the rhizosphere, for its own benefits, such as plant growth promotion as well as protection from metal toxicity. This review intends to seek out information on the rhizo-immobilization of Cd in polluted soils using the PGPR along with plant nutrient fertilizers. This review suggests that the rhizo-immobilization of Cd by a combination of PGPR and nanohybrid-based plant nutrient fertilizers would be a potential and sustainable technology for phytoavailable Cd immobilization in the rhizosphere and plant cellular detoxification, by keeping the plant nutrition flow and green dynamics of plant nutrition and boosting the plant growth and development under Cd stress.
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Affiliation(s)
- Md Abdul Halim
- Global Centre for Environmental Remediation (GCER), The University of Newcastle, Callaghan, New South Wales 2308, Australia
- Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), The University of Newcastle, Callaghan, New South Wales 2308, Australia
- Department of Biotechnology, Sher-e-Bangla Agricultural University, Dhaka 1207, Bangladesh
| | - Mohammad Mahmudur Rahman
- Global Centre for Environmental Remediation (GCER), The University of Newcastle, Callaghan, New South Wales 2308, Australia
- Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), The University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - Mallavarapu Megharaj
- Global Centre for Environmental Remediation (GCER), The University of Newcastle, Callaghan, New South Wales 2308, Australia
- Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), The University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - Ravi Naidu
- Global Centre for Environmental Remediation (GCER), The University of Newcastle, Callaghan, New South Wales 2308, Australia
- Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), The University of Newcastle, Callaghan, New South Wales 2308, Australia
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Rossi F. Beneficial biofilms for land rehabilitation and fertilization. FEMS Microbiol Lett 2020; 367:5974273. [PMID: 33175104 DOI: 10.1093/femsle/fnaa184] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 11/06/2020] [Indexed: 12/24/2022] Open
Abstract
The acquisition of a biofilm lifestyle is common in nature for microorganisms. It increases their biotic and abiotic stress tolerance and their capability to provide ecosystem services. Although diminutive communities, soil beneficial biofilms are essential for nutrient cycling, soil stabilization and direct or indirect promotion of plant development. Some biofilms represent valid biotechnological tools to deal with problems related to soil degradation, which threat food quality and the maintenance of ecosystem functions. Three genres of biofilms: rhizobacterial biofilms, fungal-bacterial biofilms and biocrusts are reviewed, and their beneficial effects on the environment outlined. Their induction by microbial inoculation represents a potential eco-friendly and sustainable approach to restore lost ecosystem functions and counteract the effects of soil erosion. Yet, some existing knowledge and methodological gaps, that will be discussed here, still hamper the optimization of this technology, and its application at its full potential.
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Affiliation(s)
- Federico Rossi
- Department of Environmental Sciences, Informatics and Statistics (DAIS), Cà Foscari University of Venice, Via Torino 155, 30172 Mestre, Venice, Italy
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Goswami M, Deka S. Isolation of a novel rhizobacteria having multiple plant growth promoting traits and antifungal activity against certain phytopathogens. Microbiol Res 2020; 240:126516. [DOI: 10.1016/j.micres.2020.126516] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 05/03/2020] [Accepted: 05/04/2020] [Indexed: 10/24/2022]
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Yasmeen T, Ahmad A, Arif MS, Mubin M, Rehman K, Shahzad SM, Iqbal S, Rizwan M, Ali S, Alyemeni MN, Wijaya L. Biofilm forming rhizobacteria enhance growth and salt tolerance in sunflower plants by stimulating antioxidant enzymes activity. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 156:242-256. [PMID: 32979797 DOI: 10.1016/j.plaphy.2020.09.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 09/04/2020] [Indexed: 05/25/2023]
Abstract
Salinity stress is one of the major environmental stresses that impose global socio-economic impacts, as well as hindering crop productivity. Halotolerant plant growth-promoting rhizobacteria (PGPR) having potential to cope with salinity stress can be employed to counter this issue in eco-friendly way. In the present investigation, halotolerant PGPR strains, AP6 and PB5, were isolated from saline soil and characterized for their biochemical, molecular and physiological traits. Sequencing of 16 S rRNA gene and comparative analysis confirmed the taxonomic affiliation of AP6 with Bacillus licheniformis and PB5 with Pseudomonas plecoglossicida. The study was carried out in pots with different levels of induced soil salinity viz. 0, 5, 10 and 15 dSm-1 to evaluate the potential of bacterial inoculants in counteracting salinity stress in sunflower at different plant growth stages (30, 45 and 60 days after sowing). Both the bacterial inoculants were capable of producing indole acetic acid and biofilm, solubilizing inorganic rock phosphate, and also expressed ACC deaminase activity. The PGPR inoculated plants showed significantly higher fresh and dry biomass, plant height, root length and yield plant-1. Ameliorative significance of applied bacterial inoculants was also evidenced by mitigating oxidative stress through upregulation of catalase (CAT), superoxide dismutase (SOD) and guaiacol peroxidase (GPX) antioxidant enzymes. Increase in photosynthetic pigments, gas exchange activities and nutrient uptake are crucial salt stress adaptations, which were enhanced with the inoculation of salt tolerant biofilm producing PGPR in sunflower plants. Although increase in salinity stress levels has gradually decreased the plant's output compared to non-salinized plants, the plants inoculated with PGPR confronted salinity stress in much better way than uninoculated plants. Owing to the wide action spectrum of these bacterial inoculants, it was concluded that these biofilm PGPR could serve as effective bioinoculants and salinity stress alleviator for sunflower (oil seed crop) by increasing crop productivity in marginalized agricultural systems.
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Affiliation(s)
- Tahira Yasmeen
- Department of Environmental Sciences and Engineering, Government College University Faisalabad, 38000, Pakistan.
| | - Aqeel Ahmad
- Department of Environmental Sciences and Engineering, Government College University Faisalabad, 38000, Pakistan
| | - Muhammad Saleem Arif
- Department of Environmental Sciences and Engineering, Government College University Faisalabad, 38000, Pakistan
| | - Muhammad Mubin
- Centre of Agricultural Biochemistry and Biotechnology, University of Agriculture, Faisalabad, Pakistan
| | - Khadija Rehman
- Department of Environmental Sciences and Engineering, Government College University Faisalabad, 38000, Pakistan
| | - Sher Muhammad Shahzad
- Department of Soil and Environmental Sciences, University College of Agriculture, University of Sargodha, Sargodha, 40100, Punjab, Pakistan
| | - Shahid Iqbal
- Key Laboratory for Economic Plants and Biotechnology, Centre for Mountain Futures CMF, East and Central Asia Regional Office, World Agroforestry Centre ICRAF, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, CN 650201, China
| | - Muhammad Rizwan
- Department of Environmental Sciences and Engineering, Government College University Faisalabad, 38000, Pakistan
| | - Shafaqat Ali
- Department of Environmental Sciences and Engineering, Government College University Faisalabad, 38000, Pakistan; Department of Biological Sciences and Technology, China Medical University, Taichung, 40402, Taiwan.
| | - Mohammed Nasser Alyemeni
- Department of Botany and Microbiology, College of Science, King Saud University, 11451, Riyadh, Saudi Arabia
| | - Leonard Wijaya
- Department of Botany and Microbiology, College of Science, King Saud University, 11451, Riyadh, Saudi Arabia
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Ahmad I, Ahmad M, Hussain A, Jamil M. Integrated use of phosphate-solubilizing Bacillus subtilis strain IA6 and zinc-solubilizing Bacillus sp. strain IA16: a promising approach for improving cotton growth. Folia Microbiol (Praha) 2020; 66:115-125. [PMID: 33099750 DOI: 10.1007/s12223-020-00831-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 10/16/2020] [Indexed: 10/23/2022]
Abstract
Mineral nutrition of crop plants is one of the major challenges faced by modern agriculture, particularly in arid and semi-arid regions. In alkaline calcareous soils, the availability of phosphorus and zinc is critically less due to their fixation and precipitation as complexes. Farmers use fertilizers to fulfill crop requirements, but their efficacy is less, which increases production costs. Plant growth-promoting rhizobacteria (PGPR) can improve the availability of crop nutrients through solubilizing the insoluble compounds of phosphorus and zinc in soil. In the present study, a total of 40 rhizobacterial isolates were isolated from cotton rhizosphere and screened for improving cotton growth through the solubilization of phosphorus and zinc. Out of these 40 isolates, seven isolates (IA2, IA3, IA6, IA7, IA8, IA13, and IA14) efficiently solubilized insoluble rock phosphate while seven isolates (IA10, IA16, IA20, IA23, IA24, IA28, and IA30) were more efficient in solubilizing insoluble zinc oxide. In liquid media, strain IA7 (2.75 μg/mL) solubilized the highest amount of phosphate while the highest concentration of soluble zinc was observed in the broth inoculated with strain IA20 (3.94 μg/mL). Seven phosphate-solubilizing and seven zinc-solubilizing strains were evaluated using jar trial to improve the growth of cotton seedlings, and the results were quite promising. All the inoculated treatments showed improvement in growth parameters in comparison with control. Best results were shown by the combined application of IA6 and IA16, followed by the combination of strains IA7 and IA20. Based on the jar trial, the selected isolates were further characterized by plant growth-promoting characters such as siderophores production, HCN production, ammonia production, and exopolysaccharides production. These strains were identified through 16S rRNA sequencing as Bacillus subtilis IA6 (accession # MN005922), Paenibacillus polymyxa IA7 (accession # MN005923), Bacillus sp. IA16 (accession # MN005924), and Bacillus aryabhattai IA20 (accession # MN005925). It is hence concluded that the integrated use of phosphate-solubilizing and zinc-solubilizing strains as potential inoculants can be a promising approach for improving cotton growth under semi-arid conditions.
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Affiliation(s)
- Iqra Ahmad
- Department of Soil Science, University College of Agriculture and Environmental Sciences, Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Maqshoof Ahmad
- Department of Soil Science, University College of Agriculture and Environmental Sciences, Islamia University of Bahawalpur, Bahawalpur, Pakistan.
| | - Azhar Hussain
- Department of Soil Science, University College of Agriculture and Environmental Sciences, Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Moazzam Jamil
- Department of Soil Science, University College of Agriculture and Environmental Sciences, Islamia University of Bahawalpur, Bahawalpur, Pakistan
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Panichikkal J, Edayileveetil Krishnankutty R. Rhizobacterial biofilm and plant growth promoting trait enhancement by organic acids and sugars. BIOFOULING 2020; 36:990-999. [PMID: 33148046 DOI: 10.1080/08927014.2020.1832219] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 09/22/2020] [Accepted: 09/29/2020] [Indexed: 06/11/2023]
Abstract
In the study,Pseudomonas sp. K6 and Pseudomonas monteilii were found to form an enhanced biofilm when cultured in the presence of organic acids and sugars. Here, the highest biofilm could be observed for Pseudomonas sp. K6 (3.08 ± 0.13) and P. monteilii (1.99 ± 0.12) when cultured in presence of 10 µM malic acid. However, maximum production of indole 3 acetic acid (IAA) was observed with 25 µM succinic acid treatment for Pseudomonas sp. K6 (24.33 ± 0.57 µg ml-1) and with 25 µM galactose for P. monteilii (20 ± 0.0 µg ml-1). At the same time, Pseudomonas sp. K6 solubilized the highest quantity of phosphate in the presence of 50 µM citric acid (21.33 ± 0.0 µM) and P. monteilii was observed to produce 32.66 ± 1.25 µM soluble phosphate in the presence of 10 µM galactose. The results of the study demonstrate the role of organic acids and sugars in the enhancement of biofilm formation, IAA production and phosphate solubilization in selected Pseudomonas spp. and highlight the potential use of rhizobacteria in conjugation with supplement for the agricultural applications.
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Affiliation(s)
- Jishma Panichikkal
- School of Biosciences, Mahatma Gandhi University, Kottayam, Kerala, India
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Kvich L, Burmølle M, Bjarnsholt T, Lichtenberg M. Do Mixed-Species Biofilms Dominate in Chronic Infections?-Need for in situ Visualization of Bacterial Organization. Front Cell Infect Microbiol 2020; 10:396. [PMID: 32850494 PMCID: PMC7419433 DOI: 10.3389/fcimb.2020.00396] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 06/29/2020] [Indexed: 12/19/2022] Open
Abstract
Chronic infections present a serious economic burden to health-care systems. The severity and prevalence of chronic infections are continuously increasing due to an aging population and an elevated number of lifestyle related diseases such as diabetes. Treatment of chronic infections has proven difficult, mainly due to the presence of biofilms that render bacteria more tolerant toward antimicrobials and the host immune response. Chronic infections have been described to harbor several different bacterial species and it has been hypothesized that microscale interactions and mixed-species consortia are present as described for most natural occurring biofilms i.e., aquatic systems and industrial settings, but also for some commensal human biofilms i.e., the mouth microbiota. However, the presence of mixed-species biofilms in chronic infections is most often an assumption based on culture-based methods and/or by means of molecular approaches, such as PCR and sequencing performed from homogenized bulk tissue samples. These methods disregard the spatial organization of the bacterial community and thus valuable information on biofilm aggregate composition, spatial organization, and possible interactions between different species is lost. Hitherto, only few studies have made visual in situ presentations of mixed-species biofilms in chronic infections, which is pivotal for the description of bacterial composition, spatial distribution, and interspecies interaction on the microscale. In order for bacteria to interact (synergism, commensalism, mutualism, competition, etc.) they need to be in close proximity to each other on the scale where they can affect e.g., solute concentrations. We argue that visual proof of mixed species biofilms in chronic infections is scarce compared to what is seen in e.g., environmental biofilms and call for a debate on the importance of mixed-species biofilm in chronic infections.
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Affiliation(s)
- Lasse Kvich
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, Costerton Biofilm Center, University of Copenhagen, Copenhagen, Denmark
| | - Mette Burmølle
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Bjarnsholt
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, Costerton Biofilm Center, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Microbiology, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | - Mads Lichtenberg
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, Costerton Biofilm Center, University of Copenhagen, Copenhagen, Denmark
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Ngoroyemoto N, Kulkarni MG, Stirk WA, Gupta S, Finnie JF, van Staden J. Interactions Between Microorganisms and a Seaweed-Derived Biostimulant on the Growth and Biochemical Composition of Amaranthus hybridus L. Nat Prod Commun 2020. [DOI: 10.1177/1934578x20934228] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Natural biostimulants such as plant growth-promoting rhizobacteria (PGPRs) and seaweed extracts are used in agriculture to improve crop yield in an environmentally friendly approach. However, interaction effects between different biostimulants are seldom investigated. This study aimed to determine the combined effect of PGPRs and Kelpak® (KEL), a seaweed-derived extract, on the growth and biochemical composition of Amaranthus hybridus, a traditional leafy vegetable of South Africa. A pot trial was conducted with 6 treatments—control (distilled water), Bacillus licheniformis (BL) inoculum, Pseudomonas fluorescens (PF) inoculum, 1% KEL, and combination treatments of KEL + BL and KEL + PF. These were applied 3 times to A. hybridus seedlings at 2 weekly intervals prior to harvesting after 6 weeks. Growth parameters and biochemical content were quantified in the harvested material. Kelpak® significantly improved growth (leaf number and area, shoot and root length, and fresh weight) and chlorophyll and carotenoid content. Treatments with 2 microorganisms had a significant negative effect on growth and pigment content. However, the combination treatments significantly improved growth and photosynthetic pigment content to similar levels as the KEL treatment. The mineral content was significantly increased for most minerals when treated with PF and decreased when treated with KEL and KEL + BL. Treatment with 2 bacterial strains and KEL caused a significant decrease in superoxidase dismutase activity with an additive effect when applied in combination. This suggests stress reduction in A. hybridus. Combined use of PGPR and seaweed extracts promises to be an eco-friendly strategy to improve the production and mineral content of traditional leafy vegetables such as A. hybridus.
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Affiliation(s)
- Nelson Ngoroyemoto
- Research Centre for Plant Growth and Development, School of Life Sciences, University of KwZulu-Natal Pietermaritzburg, Scottsville, South Africa
| | - Manoj G. Kulkarni
- Research Centre for Plant Growth and Development, School of Life Sciences, University of KwZulu-Natal Pietermaritzburg, Scottsville, South Africa
| | - Wendy A. Stirk
- Research Centre for Plant Growth and Development, School of Life Sciences, University of KwZulu-Natal Pietermaritzburg, Scottsville, South Africa
| | - Shubhpriya Gupta
- Research Centre for Plant Growth and Development, School of Life Sciences, University of KwZulu-Natal Pietermaritzburg, Scottsville, South Africa
| | - Jeffrey F. Finnie
- Research Centre for Plant Growth and Development, School of Life Sciences, University of KwZulu-Natal Pietermaritzburg, Scottsville, South Africa
| | - Johannes van Staden
- Research Centre for Plant Growth and Development, School of Life Sciences, University of KwZulu-Natal Pietermaritzburg, Scottsville, South Africa
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Co-cultivation of Beta vulgaris limits the pre-harvest colonization of foodborne pathogen (Salmonella spp.) on tomato. Int J Food Microbiol 2020; 332:108768. [PMID: 32623289 DOI: 10.1016/j.ijfoodmicro.2020.108768] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 06/11/2020] [Accepted: 06/18/2020] [Indexed: 11/23/2022]
Abstract
Soil-borne Salmonella is associated with a large number of food-related disease outbreaks linked to pre-harvest contamination of plants (like tomato) in agricultural fields. Controlling the spread of Salmonella at field is very important in order to prevent various food-borne illnesses. One such approach involves the utilization of antimicrobial secondary metabolite of plant origin. We screened common salad vegetables for anti-Salmonella activity. Beta vulgaris root (beetroot) had very low colonization of Salmonella under in vitro conditions. We hypothesized that beetroot can be used to reclaim the soil contaminated with Salmonella. Cultivation of B. vulgaris in Salmonella treated soil brings down its CFU significantly. Since these antimicrobial effects are non-specific, a co-cultivation system of beet and tomato (a Salmonella susceptible plant) was used to analyze the effect on soil and its microbiota. The soil physicochemical properties and bacterial diversity were unaffected when tomato and beet co-cultivation was used. However, Salmonella burden on the tomato was reduced and its yield was restored. Thus, the inclusion of these crops in the crop-rotation or as a mixed/intercrop or as a bio-control crop can be a fruitful tool to reclaim the Salmonella contaminated soil.
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