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Meneguzzi RDV, Fernandez M, Cappellari LDR, Giordano W, Banchio E. Isolation and Characterization of Plant Growth-Promoting Bacteria from the Rhizosphere of Medicinal and Aromatic Plant Minthostachys verticillata. PLANTS (BASEL, SWITZERLAND) 2024; 13:2062. [PMID: 39124180 PMCID: PMC11314338 DOI: 10.3390/plants13152062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2024] [Revised: 07/22/2024] [Accepted: 07/23/2024] [Indexed: 08/12/2024]
Abstract
This study aimed to isolate and characterize Pseudomonas native strains from the rhizospheric soil of Minthostachys verticillata plants to evaluate their potential as plant growth-promoting rhizobacteria (PGPR). A total of 22 bacterial isolates were obtained and subjected to various biochemical tests, as well as assessments of plant growth-promoting traits such as phosphate solubilization, hydrogen cyanide production, biocontrol properties through antibiosis, and indole acetic production. Genotypic analysis via 16S rRNA gene sequencing and phylogenetic tree construction identified the strains, with one particular strain named SM 33 showing significant growth-promoting effects on M. verticillata seedlings. This strain, SM 33, showed high similarity to Stutzerimonas stutzeri based on 16S rRNA gene sequencing and notably increased both shoot fresh weight and root dry weight of the plants. These findings underscore the potential application of native Pseudomonas strains in enhancing plant growth and health, offering promising avenues for sustainable agricultural practices.
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Affiliation(s)
| | | | | | | | - Erika Banchio
- INBIAS Instituto de Biotecnología Ambiental y Salud, CONICET-Universidad Nacional de Río Cuarto, Río Cuarto 5800, Argentina; (R.d.V.M.); (M.F.); (L.d.R.C.); (W.G.)
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Lv J, Yang S, Zhou W, Liu Z, Tan J, Wei M. Microbial regulation of plant secondary metabolites: Impact, mechanisms and prospects. Microbiol Res 2024; 283:127688. [PMID: 38479233 DOI: 10.1016/j.micres.2024.127688] [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: 01/15/2024] [Revised: 03/06/2024] [Accepted: 03/07/2024] [Indexed: 04/17/2024]
Abstract
Plant secondary metabolites possess a wide range of pharmacological activities and play crucial biological roles. They serve as both a defense response during pathogen attack and a valuable drug resource. The role of microorganisms in the regulation of plant secondary metabolism has been widely recognized. The addition of specific microorganisms can increase the synthesis of secondary metabolites, and their beneficial effects depend on environmental factors and plant-related microorganisms. This article summarizes the impact and regulatory mechanisms of different microorganisms on the main secondary metabolic products of plants. We emphasize the mechanisms by which microorganisms regulate hormone levels, nutrient absorption, the supply of precursor substances, and enzyme and gene expression to promote the accumulation of plant secondary metabolites. In addition, the possible negative feedback regulation of microorganisms is discussed. The identification of additional unknown microbes and other driving factors affecting plant secondary metabolism is essential. The prospects for further analysis of medicinal plant genomes and the establishment of a genetic operation system for plant secondary metabolism research are proposed. This study provides new ideas for the use of microbial resources for biological synthesis research and the improvement of crop anti-inverse traits for the use of microbial resources.
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Affiliation(s)
- Jiayan Lv
- School of Agriculture, Shenzhen Campus, Sun Yat-sen University, Guangdong, Shenzhen 518107, China
| | - Shuangyu Yang
- School of Agriculture, Shenzhen Campus, Sun Yat-sen University, Guangdong, Shenzhen 518107, China
| | - Wei Zhou
- School of Agriculture, Shenzhen Campus, Sun Yat-sen University, Guangdong, Shenzhen 518107, China
| | - Zhongwang Liu
- School of Agriculture, Shenzhen Campus, Sun Yat-sen University, Guangdong, Shenzhen 518107, China
| | - Jinfang Tan
- School of Agriculture, Shenzhen Campus, Sun Yat-sen University, Guangdong, Shenzhen 518107, China
| | - Mi Wei
- School of Agriculture, Shenzhen Campus, Sun Yat-sen University, Guangdong, Shenzhen 518107, China; Key Laboratory for Quality Control of Characteristic Fruits and Vegetables of Hubei Province, College of Life Science and Technology, Hubei Engineering University, Xiaogan 432000, China.
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Palermo TB, Cappellari LDR, Palermo JS, Giordano W, Banchio E. Simultaneous Impact of Rhizobacteria Inoculation and Leaf-Chewing Insect Herbivory on Essential Oil Production and VOC Emissions in Ocimum basilicum. PLANTS (BASEL, SWITZERLAND) 2024; 13:932. [PMID: 38611463 PMCID: PMC11013597 DOI: 10.3390/plants13070932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 03/19/2024] [Accepted: 03/21/2024] [Indexed: 04/14/2024]
Abstract
Inoculation with rhizobacteria and feeding by herbivores, two types of abiotic stress, have been shown to increase the production of secondary metabolites in plants as part of the defense response. This study explored the simultaneous effects of inoculation with Bacillus amyloliquefaciens GB03 (a PGPR species) and herbivory by third-instar Spodoptera frugiperda larvae on essential oil (EO) yield and volatile organic compound (VOC) emissions in Ocimum basilicum plants. The density of glandular trichomes was also examined, given that they are linked to EO production and VOC emission. Herbivory increased EO content, but inoculation on its own did not. When combined, however, the two treatments led to a 10-fold rise in EO content with respect to non-inoculated plants. VOC emissions did not significantly differ between inoculated and non-inoculated plants, but they doubled in plants chewed by the larvae with respect to their undamaged counterparts. Interestingly, no changes were observed in VOC emissions when the treatments were tested together. In short, the two biotic stressors elicited differing plant defense responses, mainly when EO was concerned. PGPR did not stimulate EO production, while herbivory significantly enhanced it and increased VOC emissions. The combined treatment acted synergistically, and in this case, PGPR inoculation may have had a priming effect that amplified plant response to herbivory. Peltate trichome density was higher in inoculated plants, those damaged by larvae, and those subjected to the combination of both treatments. The findings highlight the intricate nature of plant defense mechanisms against various stressors and hint at a potential strategy to produce essential oil through the combined application of the two stressors tested here.
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Affiliation(s)
| | | | | | | | - Erika Banchio
- INBIAS Instituto de Biotecnología Ambiental y Salud (CONICET—Universidad Nacional de Río Cuarto), Campus Universitario, Río Cuarto 5800, Argentina (L.d.R.C.)
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Gil SS, Cappellari LDR, Giordano W, Banchio E. Antifungal Activity and Alleviation of Salt Stress by Volatile Organic Compounds of Native Pseudomonas Obtained from Mentha piperita. PLANTS (BASEL, SWITZERLAND) 2023; 12:1488. [PMID: 37050113 PMCID: PMC10097229 DOI: 10.3390/plants12071488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 03/07/2023] [Accepted: 03/27/2023] [Indexed: 06/19/2023]
Abstract
As salt stress has a negative impact on plant growth and crop yield, it is very important to identify and develop any available biotechnology which can improve the salt tolerance of plants. Inoculation with plant-growth-promoting rhizobacteria (PGPR) is a proven environmentally friendly biotechnological resource for increasing the salt stress tolerance of plants and has a potential in-field application. In addition, bacterial volatile organic compounds (mVOCs) are signal molecules that may have beneficial roles in the soil-plant-microbiome ecosystem. We investigated the effects of mVOCs emitted by Pseudomona putida SJ46 and SJ04 on Mentha piperita grown under different levels of NaCl stress by evaluating their growth-promoting potential and capacity to increase salt tolerance effects. Furthermore, we evaluated under control and salt stress conditions the biocontrol ability of VOCs emitted by both these strains to inhibit the growth of Alternaria alternata and Sclerotium rolfsii. The VOCs emitted by both strains under control conditions did not lead to an significant improvement in peppermint growth. However, under salt stress conditions (75 or 100 mM NaCl), an amelioration of its physiological status was observed, with this effect being greater at 100 mM NaCl. This led to an enhancement of the number of leaves and nodes and, increased the shoot fresh and root dry weight by approximately twice in relation to control stressed plants. Moreover, the VOCs released by the two bacteria grown in control or saline media showed a significant reduction in the mycelial growth of A. alternata. In contrast, S. rolfsii growth was reduced 40% by the mVOCs released only under control conditions, with no effects being observed under salt stress. We also explored the composition of the bacterial volatile profiles by means of a solid-phase microextraction/gas chromatography-mass spectrometry (SPME/GC-MS) analysis. From the headspace of SJ46, three VOCs were identified: n-octanol, decane and tetradecane. The emission of SJ04 had the same chromatographic profile, with the addition of two more compounds: 1-(N-phenyl carbamyl)-2-morpholino cyclohexene and tridecane. Only compounds that were not present in the headspace of the control groups were recorded. The salt stress conditions where the bacteria were grown did not qualitatively modify the mVOC emissions. Taken together, our results suggest that plant-associated rhizobacterial VOCs play a potentially important role in modulating plant salt tolerance and reducing fungal growth. Thus, biological resources represent novel tools for counteracting the deleterious effects of salt stress and have the potential to be exploited in sustainable agriculture. Nevertheless, future studies are necessary to investigate technological improvements for bacterial VOC application under greenhouse and open field conditions.
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Cortazar-Murillo EM, Méndez-Bravo A, Monribot-Villanueva JL, Garay-Serrano E, Kiel-Martínez AL, Ramírez-Vázquez M, Guevara-Avendaño E, Méndez-Bravo A, Guerrero-Analco JA, Reverchon F. Biocontrol and plant growth promoting traits of two avocado rhizobacteria are orchestrated by the emission of diffusible and volatile compounds. Front Microbiol 2023; 14:1152597. [PMID: 37206331 PMCID: PMC10189041 DOI: 10.3389/fmicb.2023.1152597] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Accepted: 04/10/2023] [Indexed: 05/21/2023] Open
Abstract
Avocado (Persea americana Mill.) is a tree crop of great social and economic importance. However, the crop productivity is hindered by fast-spreading diseases, which calls for the search of new biocontrol alternatives to mitigate the impact of avocado phytopathogens. Our objectives were to evaluate the antimicrobial activity of diffusible and volatile organic compounds (VOCs) produced by two avocado rhizobacteria (Bacillus A8a and HA) against phytopathogens Fusarium solani, Fusarium kuroshium, and Phytophthora cinnamomi, and assess their plant growth promoting effect in Arabidopsis thaliana. We found that, in vitro, VOCs emitted by both bacterial strains inhibited mycelial growth of the tested pathogens by at least 20%. Identification of bacterial VOCs by gas chromatography coupled to mass spectrometry (GC-MS) showed a predominance of ketones, alcohols and nitrogenous compounds, previously reported for their antimicrobial activity. Bacterial organic extracts obtained with ethyl acetate significantly reduced mycelial growth of F. solani, F. kuroshium, and P. cinnamomi, the highest inhibition being displayed by those from strain A8a (32, 77, and 100% inhibition, respectively). Tentative identifications carried out by liquid chromatography coupled to accurate mass spectrometry of diffusible metabolites in the bacterial extracts, evidenced the presence of some polyketides such as macrolactins and difficidin, hybrid peptides including bacillaene, and non-ribosomal peptides such as bacilysin, which have also been described in Bacillus spp. for antimicrobial activities. The plant growth regulator indole-3-acetic acid was also identified in the bacterial extracts. In vitro assays showed that VOCs from strain HA and diffusible compounds from strain A8a modified root development and increased fresh weight of A. thaliana. These compounds differentially activated several hormonal signaling pathways involved in development and defense responses in A. thaliana, such as auxin, jasmonic acid (JA) and salicylic acid (SA); genetic analyses suggested that developmental stimulation of the root system architecture by strain A8a was mediated by the auxin signaling pathway. Furthermore, both strains were able to enhance plant growth and decreased the symptoms of Fusarium wilt in A. thaliana when soil-inoculated. Collectively, our results evidence the potential of these two rhizobacterial strains and their metabolites as biocontrol agents of avocado pathogens and as biofertilizers.
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Affiliation(s)
| | - Alfonso Méndez-Bravo
- CONACyT – Escuela Nacional de Estudios Superiores, Unidad Morelia, Laboratorio Nacional de Análisis y Síntesis Ecológica, Universidad Nacional Autónoma de México, Morelia, Michoacán, Mexico
| | | | - Edith Garay-Serrano
- CONACyT – Red de Diversidad Biológica del Occidente Mexicano, Centro Regional del Bajío, Instituto de Ecología, A.C., Pátzcuaro, Michoacán, Mexico
| | - Ana L. Kiel-Martínez
- Red de Estudios Moleculares Avanzados, Instituto de Ecología, A.C., Xalapa, Veracruz, Mexico
| | - Mónica Ramírez-Vázquez
- Red de Estudios Moleculares Avanzados, Instituto de Ecología, A.C., Xalapa, Veracruz, Mexico
- Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Edgar Guevara-Avendaño
- Red de Estudios Moleculares Avanzados, Instituto de Ecología, A.C., Xalapa, Veracruz, Mexico
| | - Alejandro Méndez-Bravo
- Escuela Nacional de Estudios Superiores Unidad Morelia, Laboratorio Nacional de Análisis y Síntesis Ecológica, Universidad Nacional Autónoma de México, Morelia, Mexico
| | - José A. Guerrero-Analco
- Red de Estudios Moleculares Avanzados, Instituto de Ecología, A.C., Xalapa, Veracruz, Mexico
- *Correspondence: José A. Guerrero-Analco,
| | - Frédérique Reverchon
- Red de Diversidad Biológica del Occidente Mexicano, Centro Regional del Bajío, Instituto de Ecología, A.C., Pátzcuaro, Michoacán, Mexico
- Frédérique Reverchon,
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Powell A, Wilder SL, Housh AB, Scott S, Benoit M, Powell G, Waller S, Guthrie JM, Schueller MJ, Ferrieri RA. Examining effects of rhizobacteria in relieving abiotic crop stresses using carbon-11 radiotracing. PHYSIOLOGIA PLANTARUM 2022; 174:e13675. [PMID: 35316539 PMCID: PMC9310733 DOI: 10.1111/ppl.13675] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 02/24/2022] [Accepted: 03/17/2022] [Indexed: 06/12/2023]
Abstract
In agriculture, plant growth promoting bacteria (PGPB) are increasingly used for reducing environmental stress-related crop losses through mutualistic actions of these microorganisms, activating physiological and biochemical responses, building tolerances within their hosts. Here we report the use of radioactive carbon-11 (t½ 20.4 min) to examine the metabolic and physiological responses of Zea mays to Azospirillum brasilense (HM053) inoculation while plants were subjected to salinity and low nitrogen stresses. Host metabolism of "new" carbon resources (as 11 C) and physiology including [11 C]-photosynthate translocation were measured in response to imposed growth conditions. Salinity stress caused shortened, dense root growth with a 6-fold increase in foliar [11 C]-raffinose, a potent osmolyte. ICP-MS analyses revealed increased foliar Na+ levels at the expense of K+ . HM053 inoculation relieved these effects, reinstating normal root growth, lowering [11 C]-raffinose levels while increasing [11 C]-sucrose and its translocation to the roots. Na+ levels remained elevated with inoculation, but K+ levels were boosted slightly. Low nitrogen stress yielded longer roots possessing high levels of anthocyanins. Metabolic analysis revealed significant shifts in "new" carbon partitioning into the amino acid pool under low nitrogen stress, with significant increases in foliar [11 C]-glutamate, [11 C]-aspartate, and [11 C]-asparagine, a noted osmoprotectant. 11 CO2 fixation and [11 C]-photosynthate translocation also decreased, limiting carbon supply to roots. However, starch levels in roots were reduced under nitrogen limitation, suggesting that carbon repartitioning could be a compensatory action to support root growth. Finally, inoculation with HM053 re-instated normal root growth, reduced anthocyanin, boosted root starch, and returned 11 C-allocation levels back to those of unstressed plants.
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Affiliation(s)
- Avery Powell
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- School of Natural ResourcesUniversity of MissouriColumbiaMissouriUSA
| | - Stacy L. Wilder
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
| | - Alexandra B. Housh
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- Chemistry DepartmentUniversity of MissouriColumbiaMissouriUSA
- Interdisciplinary Plant GroupUniversity of MissouriColumbiaMissouriUSA
| | - Stephanie Scott
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- Department of BiochemistryUniversity of MissouriColumbiaMissouriUSA
| | - Mary Benoit
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- Division of Plant Sciences and TechnologyUniversity of MissouriColumbiaMissouriUSA
| | - Garren Powell
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- Department of BiochemistryUniversity of MissouriColumbiaMissouriUSA
| | - Spenser Waller
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- School of Natural ResourcesUniversity of MissouriColumbiaMissouriUSA
| | - James M. Guthrie
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
| | - Michael J. Schueller
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- Chemistry DepartmentUniversity of MissouriColumbiaMissouriUSA
| | - Richard A. Ferrieri
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- Chemistry DepartmentUniversity of MissouriColumbiaMissouriUSA
- Interdisciplinary Plant GroupUniversity of MissouriColumbiaMissouriUSA
- Division of Plant Sciences and TechnologyUniversity of MissouriColumbiaMissouriUSA
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Alves NSF, Kaory Inoue SG, Carneiro AR, Albino UB, Setzer WN, Maia JG, Andrade EH, da Silva JKR. Variation in Peperomia pellucida growth and secondary metabolism after rhizobacteria inoculation. PLoS One 2022; 17:e0262794. [PMID: 35061852 PMCID: PMC8785609 DOI: 10.1371/journal.pone.0262794] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 01/05/2022] [Indexed: 01/31/2023] Open
Abstract
Peperomia pellucida L. Kunth is a herb well-known for its secondary metabolites (SM) with biological potential. In this study, the variations in the SM of P. pellucida during association with rhizobacteria were evaluated. Plants were inoculated with Enterobacter asburiae and Klebsiella variicola, which were identified by sequencing of the 16S rRNA gene. The data were evaluated at 7, 21, and 30-day post inoculation (dpi). Plant-bacteria symbiosis improved plant growth and weight. Total phenolic content and phenylalanine ammonia lyase enzyme activity had a significant increase mainly at 30 dpi. P. pellucida was mainly composed of phenylpropanoids (37.30-52.28%) and sesquiterpene hydrocarbons (39.28-49.42%). The phenylpropanoid derivative 2,4,5-trimethoxy-styrene (ArC2), the sesquiterpene hydrocarbon ishwarane, and the phenylpropanoid dillapiole were the major compounds. Principal component analysis (PCA) of the classes and compounds ≥ 2.0% indicated that plants colonized by E. asburiae had a reduction in the content of sesquiterpene hydrocarbons and an increase in phenylpropanoids and derivatives. Plants treated with this bacterium also had an increase in the content of 2,4,5-trimethoxystyrene at 30 dpi. Plants inoculated with K. variicola had significant increases only in the content of the classes monoterpene hydrocarbons and 'other compounds' (hydrocarbons, esters, ketones, etc.). These data suggest that the production of plant secondary metabolites can be modified depending on the type of rhizobacteria inoculated.
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Affiliation(s)
| | | | - Adriana Ribeiro Carneiro
- Programa de Pós-Graduação em Biotecnologia, Universidade Federal do Pará,
Belém, Brazil
- Faculdade de Biotecnologia, Universidade Federal do Pará, Belém,
Brazil
| | | | - William N. Setzer
- Department of Chemistry, University of Alabama in Huntsville, Huntsville,
AL, United States of America
- Aromatic Plant Research Center, Lehi, UT, United States of
America
| | - José Guilherme Maia
- Programa de Pós-Graduação em Química, Universidade Federal do Pará,
Belém, Brazil
| | | | - Joyce Kelly R. da Silva
- Programa de Pós-Graduação em Biotecnologia, Universidade Federal do Pará,
Belém, Brazil
- Faculdade de Biotecnologia, Universidade Federal do Pará, Belém,
Brazil
- Programa de Pós-Graduação em Química, Universidade Federal do Pará,
Belém, Brazil
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Yang D, Wang L, Wang T, Zhang Y, Zhang S, Luo Y. Plant Growth-Promoting Rhizobacteria HN6 Induced the Change and Reorganization of Fusarium Microflora in the Rhizosphere of Banana Seedlings to Construct a Healthy Banana Microflora. Front Microbiol 2021; 12:685408. [PMID: 34354685 PMCID: PMC8329250 DOI: 10.3389/fmicb.2021.685408] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 06/16/2021] [Indexed: 11/21/2022] Open
Abstract
Streptomyces aureoverticillatus HN6 was isolated in our previous study and effectively controlled banana Fusarium wilt. We explored the role of HN6 in constructing a healthy rhizosphere microflora of banana seedlings. The method of antibiotic resistance was used to determine the colonization ability of HN6. The effect of HN6 on the rhizosphere microbial communities was assessed using culture-dependent and high-throughput sequencing. The effect of HN6 on the infection process of the pathogen was evaluated using a pot experiment and confocal laser scanning microscopy. The results showed that HN6 could prevent pathogen infection; it increased the nutrient content and diversity of the bacterial community in the rhizosphere, promoted plant growth, and decreased the mycotoxin fusaric acid content and abundance of pathogens in the banana rhizosphere. Thus, HN6 decreased the relative abundance of Fusarium species, increased the diversity of fungi, and increased the relative abundance of bacteria in the rhizosphere. HN6 induced the change and reorganization of the microbial community dominated by Fusarium in the rhizosphere of banana seedlings, and it evolved into a community dominated that was not conducive to the occurrence of diseases, shaping the rhizosphere microflora and promoting the growth of banana.
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Affiliation(s)
- Deyou Yang
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou, China
| | - Lanying Wang
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou, China
| | - Tianhao Wang
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou, China
| | - Yunfei Zhang
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou, China
| | - Shujing Zhang
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou, China
| | - Yanping Luo
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou, China
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Mohanty P, Singh PK, Chakraborty D, Mishra S, Pattnaik R. Insight Into the Role of PGPR in Sustainable Agriculture and Environment. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2021. [DOI: 10.3389/fsufs.2021.667150] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
A multitude of roles is played by microbes in food and agriculture that include nutrient cycling and management, organic matter decomposition and fermentation. Plant growth promoting rhizobacteria (PGPR), representing microbial groups and with ability of colonizing plant roots, influence plant growth through various indirect and direct modes in order to promote its growth and/or protect it from diseases or damage due to insect attack. Thus, PGPR research has received renewed interest worldwide. Increasing number of crop-specific PGPR are being commercialized these days. Approaches like seed-inoculation and soil application either alone or in combination with bacterial culture/product for increased nutrient availability through phosphate solubilisation, potassium solubilisation, sulfur oxidation, nitrogen fixation, iron, and copper chelation are gaining popularity. Arbuscular mycorrhizal fungi (AMF) are root fungal symbiont that improve management of abiotic stress such as phosphorus deficiency. PGPR involves roles like production of indole acetic acid (IAA), ammonia (NH3), hydrogen cyanide (HCN), catalase, etc. PGPR also improve nutrient uptake by altering the level of plant hormone that enhances root surface area by increasing its girth and shape, thereby helping in absorbing more nutrients. PGPR facilitate seed germination, seedling growth and crop yield. An array of microbes including Pseudomonas, Azospirillum, Azotobacter, Klebsiella, Enterobacter, Alcaligenes, Arthrobacter, Burkholderia, Bacillus, and Serratia enhance plant growth. Various Pseudomonas sp. have demonstrated significant increase in germination, seedling growth and yield in different agricultural crops, including wheat. Hence, developing a successful crop-specific PGPR formulation, the candidate should possess characteristics like high rhizosphere competence, extensive competitive saprophytic ability, growth enhancing ability, ease of mass production, broad-spectrum action, safety toward the environment and compatibility with other partnering organisms.
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Bacterial Plant Biostimulants: A Sustainable Way towards Improving Growth, Productivity, and Health of Crops. SUSTAINABILITY 2021. [DOI: 10.3390/su13052856] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
This review presents a comprehensive and systematic study of the field of bacterial plant biostimulants and considers the fundamental and innovative principles underlying this technology. Plant biostimulants are an important tool for modern agriculture as part of an integrated crop management (ICM) system, helping make agriculture more sustainable and resilient. Plant biostimulants contain substance(s) and/or microorganisms whose function when applied to plants or the rhizosphere is to stimulate natural processes to enhance plant nutrient uptake, nutrient use efficiency, tolerance to abiotic stress, biocontrol, and crop quality. The use of plant biostimulants has gained substantial and significant heed worldwide as an environmentally friendly alternative to sustainable agricultural production. At present, there is an increasing curiosity in industry and researchers about microbial biostimulants, especially bacterial plant biostimulants (BPBs), to improve crop growth and productivity. The BPBs that are based on PGPR (plant growth-promoting rhizobacteria) play plausible roles to promote/stimulate crop plant growth through several mechanisms that include (i) nutrient acquisition by nitrogen (N2) fixation and solubilization of insoluble minerals (P, K, Zn), organic acids and siderophores; (ii) antimicrobial metabolites and various lytic enzymes; (iii) the action of growth regulators and stress-responsive/induced phytohormones; (iv) ameliorating abiotic stress such as drought, high soil salinity, extreme temperatures, oxidative stress, and heavy metals by using different modes of action; and (v) plant defense induction modes. Presented here is a brief review emphasizing the applicability of BPBs as an innovative exertion to fulfill the current food crisis.
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Liang JP, Xue ZQ, Yang ZY, Chai Z, Niu JP, Shi ZY. Effects of microbial organic fertilizers on Astragalus membranaceus growth and rhizosphere microbial community. ANN MICROBIOL 2021. [DOI: 10.1186/s13213-021-01623-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Abstract
Purpose
The application of excessive chemical fertilizers during the cultivation of Astragalus membranaceus leads to a decline in the quality of this medicinal plant as well as the soil’s sustainable productivity. In this study, we developed a special microbial organic fertilizer for A. membranaceus and investigated its effects on plant growth and rhizosphere microbial communities.
Methods
The root biomass and main active components of A. membranaceus in different growth stages were measured to assess the impacts of microbial organic manure on plant growth. Meanwhile, 16S rRNA and ITS1 amplicons were amplified and high-throughput sequencing was performed to detect the dynamic impacts of microbial organic manure on rhizosphere microbial communities.
Result
The results demonstrated that microbial organic manure significantly increased wet and dry weights of A. membranaceus seedlings and the accumulation of two effective components (flavonoids and saponin) in bacterial fertilizer treatment groups are significant higher than the control group. Research on rhizosphere microbial flora shows that the number and polymorphism of bacteria and fungi were decreased after the application of special fertilizer during the rapid growth period of plant and then gradually increased with seedling growth. The community structure of bacteria was regulated after the application of special fertilizer, and the beneficial bacteria for plant growth are enriched. Functional profiles prediction showed that significant shifts in metabolic functions impacting KEGG pathways of the microbial fertilizer treatment groups are related to metabolism and biosynthesis.
Conclusion
The results indicate that the microbial organic manure can improve A. membranaceus growth by providing appropriate nutrients and regulating the rhizosphere microbial community which has good potential in ecological cultivation of A. membranaceus.
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del Rosario Cappellari L, Chiappero J, Palermo TB, Giordano W, Banchio E. Impact of Soil Rhizobacteria Inoculation and Leaf-Chewing Insect Herbivory on Mentha piperita Leaf Secondary Metabolites. J Chem Ecol 2020; 46:619-630. [DOI: 10.1007/s10886-020-01193-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 06/05/2020] [Accepted: 06/17/2020] [Indexed: 12/11/2022]
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Liu Z, Zhou J, Li Y, Wen J, Wang R. Bacterial endophytes from Lycoris radiata promote the accumulation of Amaryllidaceae alkaloids. Microbiol Res 2020; 239:126501. [PMID: 32585579 DOI: 10.1016/j.micres.2020.126501] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 04/23/2020] [Accepted: 04/25/2020] [Indexed: 11/28/2022]
Abstract
Lycoris radiata is the major source of Amaryllidaceae alkaloids, having various medicinal activities. However, the low content of these alkaloids in planta limits their pharmaceutical development and utilization. In this study, the ability of bacterial endophytes to enhance the accumulation of five important Amaryllidaceae alkaloids was investigated. A total of 188 bacterial endophytes were isolated from L. radiata and their composition and diversity were analyzed. Fourteen ones were demonstrated to significantly increase the concentration of the alkaloids of interest in different organs, up to 11.1-fold over the control level, with no adverse influence on the plant growth. An additional 3 bacterial endophytes were found to significantly increase the dry weight of L. radiata with no adverse influence on the concentration of the alkaloids in planta, so the total yield of alkaloids in planta was increased up to 2.4-fold over the control level. Considering the plant growth-promoting abilities of these bacterial endophytes, it is speculated that the indole-3-acetic acid and siderophore secreted by them, combined with their nitrogen fixation ability, may contribute to the enhanced plant growth and the increased alkaloid accumulation in L. radiata. To our knowledge, this work is firstly defining the diversity of culturable bacterial endophytes in L. radiata and determining which species promoted the accumulation of Amaryllidaceae alkaloids. It provides several valuable bacterial inoculants that can be further applied to improve alkaloid production in L. radiata and broadens our understanding of the interactions between a medicinal plant and the bacterial endophytes.
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Affiliation(s)
- Zhilin Liu
- Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, The Jiangsu Provincial Platform for Conservation and Utilization of Agricultural Germplasm, Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing, Jiangsu, China
| | - Jiayu Zhou
- Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, The Jiangsu Provincial Platform for Conservation and Utilization of Agricultural Germplasm, Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing, Jiangsu, China
| | - Yikui Li
- Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, The Jiangsu Provincial Platform for Conservation and Utilization of Agricultural Germplasm, Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing, Jiangsu, China
| | - Jian Wen
- Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, The Jiangsu Provincial Platform for Conservation and Utilization of Agricultural Germplasm, Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing, Jiangsu, China
| | - Ren Wang
- Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, The Jiangsu Provincial Platform for Conservation and Utilization of Agricultural Germplasm, Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing, Jiangsu, China.
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Kang SM, Asaf S, Khan AL, Lubna, Khan A, Mun BG, Khan MA, Gul H, Lee IJ. Complete Genome Sequence of Pseudomonas psychrotolerans CS51, a Plant Growth-Promoting Bacterium, Under Heavy Metal Stress Conditions. Microorganisms 2020; 8:E382. [PMID: 32182882 PMCID: PMC7142416 DOI: 10.3390/microorganisms8030382] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 02/26/2020] [Accepted: 03/03/2020] [Indexed: 12/02/2022] Open
Abstract
In the current study, we aimed to elucidate the plant growth-promoting characteristics of Pseudomonas psychrotolerans CS51 under heavy metal stress conditions (Zn, Cu, and Cd) and determine the genetic makeup of the CS51 genome using the single-molecule real-time (SMRT) sequencing technology of Pacific Biosciences. The results revealed that inoculation with CS51 induced endogenous indole-3-acetic acid (IAA) and gibberellins (GAs), which significantly enhanced cucumber growth (root shoot length) and increased the heavy metal tolerance of cucumber plants. Moreover, genomic analysis revealed that the CS51 genome consisted of a circular chromosome of 5,364,174 base pairs with an average G+C content of 64.71%. There were around 4774 predicted protein-coding sequences (CDSs) in 4859 genes, 15 rRNA genes, and 67 tRNA genes. Around 3950 protein-coding genes with function prediction and 733 genes without function prediction were identified. Furthermore, functional analyses predicted that the CS51 genome could encode genes required for auxin biosynthesis, nitrate and nitrite ammonification, the phosphate-specific transport system, and the sulfate transport system, which are beneficial for plant growth promotion. The heavy metal resistance of CS51 was confirmed by the presence of genes responsible for cobalt-zinc-cadmium resistance, nickel transport, and copper homeostasis in the CS51 genome. The extrapolation of the curve showed that the core genome contained a minimum of 2122 genes (95% confidence interval = 2034.24 to 2080.215). Our findings indicated that the genome sequence of CS51 may be used as an eco-friendly bioresource to promote plant growth in heavy metal-contaminated areas.
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Affiliation(s)
- Sang-Mo Kang
- School of Applied Biosciences, Kyungpook National University, Daegu 41566, Korea; (S.-M.K.); (B.-G.M.); (M.A.K.)
| | - Sajjad Asaf
- Natural and Medical Sciences Research Center, University of Nizwa, Nizwa 616, Oman; (S.A.); (A.L.K.); (A.K.)
| | - Abdul Latif Khan
- Natural and Medical Sciences Research Center, University of Nizwa, Nizwa 616, Oman; (S.A.); (A.L.K.); (A.K.)
| | - Lubna
- Department of Botany, Garden Campus, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan; (L.); (H.G.)
| | - Adil Khan
- Natural and Medical Sciences Research Center, University of Nizwa, Nizwa 616, Oman; (S.A.); (A.L.K.); (A.K.)
| | - Bong-Gyu Mun
- School of Applied Biosciences, Kyungpook National University, Daegu 41566, Korea; (S.-M.K.); (B.-G.M.); (M.A.K.)
| | - Muhammad Aaqil Khan
- School of Applied Biosciences, Kyungpook National University, Daegu 41566, Korea; (S.-M.K.); (B.-G.M.); (M.A.K.)
| | - Humaira Gul
- Department of Botany, Garden Campus, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan; (L.); (H.G.)
| | - In-Jung Lee
- School of Applied Biosciences, Kyungpook National University, Daegu 41566, Korea; (S.-M.K.); (B.-G.M.); (M.A.K.)
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15
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Kalemba D, Synowiec A. Agrobiological Interactions of Essential Oils of Two Menthol Mints: Mentha piperita and Mentha arvensis. Molecules 2019; 25:molecules25010059. [PMID: 31878007 PMCID: PMC6983130 DOI: 10.3390/molecules25010059] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 12/17/2019] [Accepted: 12/20/2019] [Indexed: 12/23/2022] Open
Abstract
This review article discusses the active constituents and potential of two menthol mint oils, Mentha piperita (MPEO) and Mentha arvensis (MAEO), as natural sources for botanical pesticides. The biological activities of these menthol mint oils, which can be useful in agriculture, have been broadly researched, especially toward phytotoxic microorganisms. To a lesser extent, the insecticidal and herbicidal activities of mint EOs have also been studied. It is apparent that the prospect of using menthol mint oils in agriculture is increasing in popularity. A number of investigations showed that the in vitro efficacy of MPEO and MAEO, as well as that of their main constituent, menthol, is pronounced. The results of in vitro research are useful for choosing EOs for further investigations. However, it is clear that in situ experiments are crucial and should be more extensively developed. At the same time, known techniques are to be applied to this area and new methods should be worked out, aiming at the improvement of EOs’ pesticidal efficacy and cost-effectiveness, for future implementation in agricultural pest control.
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Affiliation(s)
- Danuta Kalemba
- Institute of Natural Products and Cosmetics, Lodz University of Technology, 90-924 Łódź, Poland;
| | - Agnieszka Synowiec
- LeStudium Institute for Advanced Studies, 45000 Orléans, France
- Department of Agroecology and Crop Production, University of Agriculture in Kraków, 31-120 Kraków, Poland
- Correspondence: ; Tel.: +48-12-662-43-65
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16
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Cappellari LDR, Santoro MV, Schmidt A, Gershenzon J, Banchio E. Improving Phenolic Total Content and Monoterpene in Mentha x piperita by Using Salicylic Acid or Methyl Jasmonate Combined with Rhizobacteria Inoculation. Int J Mol Sci 2019; 21:E50. [PMID: 31861733 PMCID: PMC6981552 DOI: 10.3390/ijms21010050] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Revised: 12/13/2019] [Accepted: 12/16/2019] [Indexed: 01/23/2023] Open
Abstract
The effects of plant inoculation with plant growth-promoting rhizobacteria (PGPR) and those resulting from the exogenous application of salicylic acid (SA) or methyl jasmonte (MeJA) on total phenolic content (TPC) and monoterpenes in Mentha x piperita plants were investigated. Although the PGPR inoculation response has been studied for many plant species, the combination of PGPR and exogenous phytohormones has not been investigated in aromatic plant species. The exogenous application of SA produced an increase in TPC that, in general, was of a similar level when applied alone as when combined with PGPR. This increase in TPC was correlated with an increase in the activity of the enzyme phenylalanine ammonia lyase (PAL). Also, the application of MeJA at different concentrations in combination with inoculation with PGPR produced an increase in TPC, which was more relevant at 4 mM, with a synergism effect being observed. With respect to the main monoterpene concentrations present in peppermint essential oil (EO), it was observed that SA or MeJA application produced a significant increase similar to that of the combination with rhizobacteria. However, when plants were exposed to 2 mM MeJA and inoculated, an important increase was produced in the concentration on menthol, pulegone, linalool, limonene, and menthone concentrations. Rhizobacteria inoculation, the treatment with SA and MeJA, and the combination of both were found to affect the amount of the main monoterpenes present in the EO of M. piperita. For this reason, the expressions of genes related to the biosynthesis of monoterpene were evaluated, with this expression being positively affected by MeJA application and PGPR inoculation, but was not modified by SA application. Our results demonstrate that MeJA or SA application combined with inoculation with PGPR constitutes an advantageous management practice for improving the production of secondary metabolites from M. piperita.
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Affiliation(s)
| | - Maricel Valeria Santoro
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07745 Jena, Germany; (M.V.S.); (A.S.)
| | - Axel Schmidt
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07745 Jena, Germany; (M.V.S.); (A.S.)
| | - Jonathan Gershenzon
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07745 Jena, Germany; (M.V.S.); (A.S.)
| | - Erika Banchio
- INBIAS (CONICET-Universidad Nacional de Río Cuarto), Campus Universitario, 5800 Río Cuarto, Argentina;
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17
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Del Rosario Cappellari L, Chiappero J, Banchio E. Invisible signals from the underground: A practical method to investigate the effect of microbial volatile organic compounds emitted by rhizobacteria on plant growth. BIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION : A BIMONTHLY PUBLICATION OF THE INTERNATIONAL UNION OF BIOCHEMISTRY AND MOLECULAR BIOLOGY 2019; 47:388-393. [PMID: 30964236 DOI: 10.1002/bmb.21243] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 01/29/2019] [Accepted: 03/23/2019] [Indexed: 06/09/2023]
Abstract
Rhizobacteria that colonize plant roots and promote plant growth are referred to as plant growth-promoting rhizobacteria, and this can stimulate plant growth either indirectly or directly. Volatile organic compounds (VOCs) emitted by rhizobacteria have the capacity to promote plant growth as well as perform biocontrol of fungal pathogens. The microbial volatile organic compounds (mVOCs) are characterized by a low molecular weight and a high vapor pressure, which facilitate evaporation and diffusion at normal temperatures and at above-ground and below-ground pressures. mVOCs can travel far from the point of production through the atmosphere, porous soils and liquids, thereby making them ideal infochemicals for mediating interspecific interactions. However, knowledge about the biological and ecological roles of microbial VOCs is still limited compared with that of plant VOCs. Here, we describe a simple and inexpensive laboratory class aimed at biotechnology or soil microbiology students, which uses techniques to increase their understanding of the mechanisms of plant growth promoting rhizobacteria and also illustrate the effects of mVOCs emitted by rhizobacteria on plant growth promotion, as well as evaluating their potential as a biocontrol. The laboratory class is divided into two sessions: an initial 3-hour experimental session and a second 2-hour analytical one. The experimental session involves two separate experiments: one of which is dedicated to illustrating the effect of mVOCs on plant growth parameters, while the second explores the capacity of VOCs as a biocontrol. Also, the class provides students with an opportunity to perform useful assays, draw conclusions from their results, and discuss possible extensions of the study. © 2019 International Union of Biochemistry and Molecular Biology, 47(4):388-393, 2019.
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Affiliation(s)
| | - Julieta Chiappero
- Departamento de Biología Molecular, Universidad Nacional de Río Cuarto, RN36 601, Río Cuarto, Córdoba, Argentina
| | - Erika Banchio
- Departamento de Biología Molecular, Universidad Nacional de Río Cuarto, RN36 601, Río Cuarto, Córdoba, Argentina
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Devi AR, Sharma GD, Majumdar PB, Pandey P. A multispecies consortium of bacteria having plant growth promotion and antifungal activities, for the management of Fusarium wilt complex disease in potato (Solanum tuberosum L.). BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2018. [DOI: 10.1016/j.bcab.2018.10.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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19
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He AL, Niu SQ, Zhao Q, Li YS, Gou JY, Gao HJ, Suo SZ, Zhang JL. Induced Salt Tolerance of Perennial Ryegrass by a Novel Bacterium Strain from the Rhizosphere of a Desert Shrub Haloxylon ammodendron. Int J Mol Sci 2018; 19:ijms19020469. [PMID: 29401742 PMCID: PMC5855691 DOI: 10.3390/ijms19020469] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Revised: 01/31/2018] [Accepted: 02/01/2018] [Indexed: 11/16/2022] Open
Abstract
Drought and soil salinity reduce agricultural output worldwide. Plant-growth-promoting rhizobacteria (PGPR) can enhance plant growth and augment plant tolerance to biotic and abiotic stresses. Haloxylon ammodendron, a C4 perennial succulent xerohalophyte shrub with excellent drought and salt tolerance, is naturally distributed in the desert area of northwest China. In our previous work, a bacterium strain numbered as M30-35 was isolated from the rhizosphere of H. ammodendron in Tengger desert, Gansu province, northwest China. In current work, the effects of M30-35 inoculation on salt tolerance of perennial ryegrass were evaluated and its genome was sequenced to identify genes associated with plant growth promotion. Results showed that M30-35 significantly enhanced growth and salt tolerance of perennial ryegrass by increasing shoot fresh and dry weights, chlorophyll content, root volume, root activity, leaf catalase activity, soluble sugar and proline contents that contributed to reduced osmotic potential, tissue K⁺ content and K⁺/Na⁺ ratio, while decreasing malondialdehyde (MDA) content and relative electric conductivity (REC), especially under higher salinity. The genome of M30-35 contains 4421 protein encoding genes, 12 rRNA, 63 tRNA-encoding genes and four rRNA operons. M30-35 was initially classified as a new species in Pseudomonas and named as Pseudomonas sp. M30-35. Thirty-four genes showing homology to genes associated with PGPR traits and abiotic stress tolerance were identified in Pseudomonas sp. M30-35 genome, including 12 related to insoluble phosphorus solubilization, four to auxin biosynthesis, four to other process of growth promotion, seven to oxidative stress alleviation, four to salt and drought tolerance and three to cold and heat tolerance. Further study is needed to clarify the correlation between these genes from M30-35 and the salt stress alleviation of inoculated plants under salt stress. Overall, our research indicated that desert shrubs appear rich in PGPRs that can help important crops tolerate abiotic stress.
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Affiliation(s)
- Ao-Lei He
- State Key Laboratory of Grassland Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China.
| | - Shu-Qi Niu
- State Key Laboratory of Grassland Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China.
| | - Qi Zhao
- State Key Laboratory of Grassland Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China.
| | - Yong-Sheng Li
- State Key Laboratory of Grassland Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China.
| | - Jing-Yi Gou
- State Key Laboratory of Grassland Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China.
| | - Hui-Juan Gao
- State Key Laboratory of Grassland Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China.
| | - Sheng-Zhou Suo
- State Key Laboratory of Grassland Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China.
| | - Jin-Lin Zhang
- State Key Laboratory of Grassland Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China.
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The current status on the taxonomy of Pseudomonas revisited: An update. INFECTION GENETICS AND EVOLUTION 2017; 57:106-116. [PMID: 29104095 DOI: 10.1016/j.meegid.2017.10.026] [Citation(s) in RCA: 131] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 10/28/2017] [Accepted: 10/30/2017] [Indexed: 12/20/2022]
Abstract
The genus Pseudomonas described in 1894 is one of the most diverse and ubiquitous bacterial genera which encompass species isolated worldwide. In the last years more than 70 new species have been described, which were isolated from different environments, including soil, water, sediments, air, animals, plants, fungi, algae, compost, human and animal related sources. Some of these species have been isolated in extreme environments, such as Antarctica or Atacama desert, and from contaminated water or soil. Also, some species recently described are plant or animal pathogens. In this review, we revised the current status of the taxonomy of genus Pseudomonas and the methodologies currently used for the description of novel species which includes, in addition to the classic ones, new methodologies such as MALDI-TOF MS, MLSA and genome analyses. The novel Pseudomonas species described in the last years are listed, together with the available genome sequences of the type strains of Pseudomonas species present in different databases.
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21
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Characterization of root-associated microbiota in medicinal plants Astragalus membranaceus and Astragalus mongholicus. ANN MICROBIOL 2017. [DOI: 10.1007/s13213-017-1285-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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Carro L, Nouioui I. Taxonomy and systematics of plant probiotic bacteria in the genomic era. AIMS Microbiol 2017; 3:383-412. [PMID: 31294168 PMCID: PMC6604993 DOI: 10.3934/microbiol.2017.3.383] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 05/22/2017] [Indexed: 12/20/2022] Open
Abstract
Recent decades have predicted significant changes within our concept of plant endophytes, from only a small number specific microorganisms being able to colonize plant tissues, to whole communities that live and interact with their hosts and each other. Many of these microorganisms are responsible for health status of the plant, and have become known in recent years as plant probiotics. Contrary to human probiotics, they belong to many different phyla and have usually had each genus analysed independently, which has resulted in lack of a complete taxonomic analysis as a group. This review scrutinizes the plant probiotic concept, and the taxonomic status of plant probiotic bacteria, based on both traditional and more recent approaches. Phylogenomic studies and genes with implications in plant-beneficial effects are discussed. This report covers some representative probiotic bacteria of the phylum Proteobacteria, Actinobacteria, Firmicutes and Bacteroidetes, but also includes minor representatives and less studied groups within these phyla which have been identified as plant probiotics.
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Affiliation(s)
- Lorena Carro
- School of Biology, Newcastle University, Newcastle upon Tyne, UK
| | - Imen Nouioui
- School of Biology, Newcastle University, Newcastle upon Tyne, UK
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23
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Nithya A, Babu S. Prevalence of plant beneficial and human pathogenic bacteria isolated from salad vegetables in India. BMC Microbiol 2017; 17:64. [PMID: 28288566 PMCID: PMC5348887 DOI: 10.1186/s12866-017-0974-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 03/07/2017] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The study aimed at enumerating, identifying and categorizing the endophytic cultivable bacterial community in selected salad vegetables (carrot, cucumber, tomato and onion). Vegetable samples were collected from markets of two vegetable hot spot growing areas, during two different crop harvest seasons. Crude and diluted vegetable extracts were plated and the population of endophytic bacteria was assessed based on morphologically distinguishable colonies. The bacterial isolates were identified by growth in selective media, biochemical tests and 16S rRNA gene sequencing. RESULTS The endophytic population was found to be comparably higher in cucumber and tomato in both of the sampling locations, whereas lower in carrot and onion. Bacterial isolates belonged to 5 classes covering 46 distinct species belonging to 19 genera. Human opportunistic pathogens were predominant in carrot and onion, whereas plant beneficial bacteria dominated in cucumber and tomato. Out of the 104 isolates, 16.25% are human pathogens and 26.5% are human opportunistic pathogens. CONCLUSIONS Existence of a high population of plant beneficial bacteria was found to have suppressed the population of plant and human pathogens. There is a greater potential to study the native endophytic plant beneficial bacteria for developing them as biocontrol agents against human pathogens that are harboured by plants.
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Affiliation(s)
- Angamuthu Nithya
- School of Bio Sciences and Technology, VIT University, Vellore, 632014, India
| | - Subramanian Babu
- School of Bio Sciences and Technology, VIT University, Vellore, 632014, India.
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