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Nawaz A, Qamar ZU, Marghoob MU, Imtiaz M, Imran A, Mubeen F. Contribution of potassium solubilizing bacteria in improved potassium assimilation and cytosolic K +/Na + ratio in rice ( Oryza sativa L.) under saline-sodic conditions. Front Microbiol 2023; 14:1196024. [PMID: 37711698 PMCID: PMC10497963 DOI: 10.3389/fmicb.2023.1196024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 07/24/2023] [Indexed: 09/16/2023] Open
Abstract
Sodium-induced potassium (K+) deficiency is more prevalent in salt-affected soils. Plants experience K+ starvation thus cytosolic K+/Na+ ratio is lowered, which is a prerequisite for their survival. K+ enrichment in crops can be acquired via K-solubilizing bacteria as a sustainable green agriculture approach. This study was conducted to explore potent K-solubilizing bacteria from the rhizosphere of wheat, rice, and native flora grown in salt-affected soils in two distinct regions of Pakistan. The aim of this work was to evaluate the contribution of microbial consortiums to the improvement of K+ assimilation and cytosolic K+/Na+ ratios in rice crops under saline-sodic conditions. Among 250 bacterial isolates, 9 were selected based on their salt (11% NaCl) and alkali (9) tolerance and K-solubilization indices (1.57-5.67). These bacterial strains were characterized for their plant growth-promoting traits and identified based on 16S rRNA gene sequencing. A consortium of five strains, namely, Enterobacter hormaechei, Citrobacter braakii, Pseudomonas putida, Erwinia iniecta, and Pantoea agglomerans, was used as a bio-inoculant to evaluate its role in K+ assimilation, cytosolic K+/Na+ ratio, and subsequent yield enhancement in rice grown under saline-sodic conditions. The impact of applied consortium on rice was assessed under variable salt levels (Control, 40, 80, and 120 mM) in a pot experiment and under natural saline-sodic conditions in the field. Plant agronomical parameters were significantly higher in the bacterial consortium-treated plants, with a concomitant increase in K+-uptake in root and shoot (0.56 and 0.35 mg g-1 dry wt.) of the salt-tolerant rice variety Shaheen. The root K+/Na+ ratio was significantly improved (200% in 40 mM and 126% in 80 mM NaCl) and in the shoot (99% in 40 mM and 131% in 80 mM) too. A similar significant increase was also observed in the salt-susceptible variety Kainat. Moreover, grain yield (30.39 g/1,000 grains wt.) and biomass (8.75 g) of the rice variety Shaheen, grown in field conditions, were also improved. It can be concluded that K-solubilizing bacteria can be used as bio-inoculants, contributing to growth and yield increment via enhanced K-assimilation and cytosolic K+/Na+ ratio in rice crops under salt stress.
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Affiliation(s)
- Aniqa Nawaz
- Microbial Physiology Laboratory, Soil and Environmental Biotechnology Division, National Institute for Biotechnology and Genetic Engineering College, Pakistan Institute of Engineering and Applied Sciences, Islamabad, Pakistan
| | - Zia Ul Qamar
- Rice Lab, Plant Breeding and Genetics Division, Nuclear Institute of Agriculture and Biology College, Pakistan Institute of Engineering and Applied Sciences, Islamabad, Pakistan
| | - Muhammad Usama Marghoob
- Microbial Physiology Laboratory, Soil and Environmental Biotechnology Division, National Institute for Biotechnology and Genetic Engineering College, Pakistan Institute of Engineering and Applied Sciences, Islamabad, Pakistan
| | - Muhammad Imtiaz
- Microbial Physiology Laboratory, Soil and Environmental Biotechnology Division, National Institute for Biotechnology and Genetic Engineering College, Pakistan Institute of Engineering and Applied Sciences, Islamabad, Pakistan
| | - Asma Imran
- Microbial Physiology Laboratory, Soil and Environmental Biotechnology Division, National Institute for Biotechnology and Genetic Engineering College, Pakistan Institute of Engineering and Applied Sciences, Islamabad, Pakistan
| | - Fathia Mubeen
- Microbial Physiology Laboratory, Soil and Environmental Biotechnology Division, National Institute for Biotechnology and Genetic Engineering College, Pakistan Institute of Engineering and Applied Sciences, Islamabad, Pakistan
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Fernandes GC, Rosa PAL, Jalal A, Oliveira CEDS, Galindo FS, Viana RDS, De Carvalho PHG, Silva ECD, Nogueira TAR, Al-Askar AA, Hashem AH, AbdElgawad H, Teixeira Filho MCM. Technological Quality of Sugarcane Inoculated with Plant-Growth-Promoting Bacteria and Residual Effect of Phosphorus Rates. PLANTS (BASEL, SWITZERLAND) 2023; 12:2699. [PMID: 37514313 PMCID: PMC10385306 DOI: 10.3390/plants12142699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 07/11/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023]
Abstract
Phosphate fertilization in highly weathered soils has been a major challenge for sugarcane production. The objective of this work was to evaluate the foliar levels of phosphorus (P) and nitrogen (N) and the technological quality and productivity of second ratoon cane as a function of inoculation with plant-growth-promoting bacteria (PGPBs) together with the residual effect of phosphate fertilization. The experiment was carried out at the research and extension farm of Ilha Solteira, state of São Paulo, Brazil. The experiment was designed in a randomized block with three replications in a 5 × 8 factorial scheme. The treatments consisted of five residual doses of phosphorus (0, 45, 90, 135 and 180 kg ha-1 of P2O5, 46% P) applied at planting from the source of triple superphosphate and eight inoculations from three species of PGPB (Azospirillum brasilense, Bacillus subtilis and Pseudomonas fluorescens), applied in single or co-inoculation at the base of stems of sugarcane variety RB92579. Inoculation with PGPBs influenced leaf N concentration, while inoculations with Pseudomonas fluorescens and combinations of bacteria together with the highest doses exerted a positive effect on leaf P concentration. Co-inoculation with A. brasilense + Pseudomonas fluorescens associated with a residual dose of 135 kg ha-1 of P2O5 increased stem productivity by 42%. Thus, it was concluded that inoculations with Pseudomonas fluorescens and their combinations are beneficial for the sugarcane crop, reducing phosphate fertilization and increasing productivity.
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Affiliation(s)
- Guilherme Carlos Fernandes
- Department of Plant Health, College of Engineering, São Paulo State University (UNESP), Rural Engineering and Soils, Ilha Solteira 15385-000, SP, Brazil
| | - Poliana Aparecida Leonel Rosa
- Department of Plant Health, College of Engineering, São Paulo State University (UNESP), Rural Engineering and Soils, Ilha Solteira 15385-000, SP, Brazil
| | - Arshad Jalal
- Department of Plant Health, College of Engineering, São Paulo State University (UNESP), Rural Engineering and Soils, Ilha Solteira 15385-000, SP, Brazil
| | - Carlos Eduardo da Silva Oliveira
- Department of Plant Health, College of Engineering, São Paulo State University (UNESP), Rural Engineering and Soils, Ilha Solteira 15385-000, SP, Brazil
| | - Fernando Shintate Galindo
- Department of Plant Production, Faculty of Agricultural and Technological Sciences, São Paulo State University (UNESP), Dracena 17900-000, SP, Brazil
| | - Ronaldo da Silva Viana
- Department of Plant Production, Faculty of Agricultural and Technological Sciences, São Paulo State University (UNESP), Dracena 17900-000, SP, Brazil
| | - Pedro Henrique Gomes De Carvalho
- Department of Plant Health, College of Engineering, São Paulo State University (UNESP), Rural Engineering and Soils, Ilha Solteira 15385-000, SP, Brazil
| | - Edson Cabral da Silva
- Department of Plant Health, College of Engineering, São Paulo State University (UNESP), Rural Engineering and Soils, Ilha Solteira 15385-000, SP, Brazil
| | - Thiago Assis Rodrigues Nogueira
- Department of Plant Health, College of Engineering, São Paulo State University (UNESP), Rural Engineering and Soils, Ilha Solteira 15385-000, SP, Brazil
- Department of Agricultural Sciences, School of Agricultural and Veterinarian Sciences, São Paulo State University (UNESP), Via do Prof Access Paulo Donato Castellane, s/n, Jabotcabal 14884-900, SP, Brazil
| | - Abdulaziz A Al-Askar
- Department of Botany and Microbiology, Faculty of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Amr H Hashem
- Botany and Microbiology Department, Faculty of Science, Al-Azhar University, Cairo 11884, Egypt
| | - Hamada AbdElgawad
- Integrated Molecular Plant Physiology Research, Department of Biology, University of Antwerp, 2020 Antwerp, Belgium
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Rawat J, Saxena J, Sanwal P, Maddela NR, Nain L, Prasad R. Improving the Growth and Productivity of Macrotyloma uniflorum Medicinal Plant by the Co-inoculation of P, Zn and K-Solubilizing Fungi Under Field Conditions. Curr Microbiol 2023; 80:277. [PMID: 37434070 DOI: 10.1007/s00284-023-03385-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 06/25/2023] [Indexed: 07/13/2023]
Abstract
The presence of small amount of soluble forms of Phosphorus (P), Potassium (K) and Zinc (Zn) in most soils is one of the limiting factors for agronomic crop production. The current study focuses on Macrotyloma uniflorum (horse gram or gahat), the most commonly cultivated crop in Uttarakhand. The current initiative and study were started, because there is a little information available on the impact of co-inoculation of beneficial fungi on crops in agricultural fields. Aspergillus niger K7 and Penicillium chrysogenum K4 were isolated and selected for the study on the basis of in vitro P, K and Zn-solubilizing activity. The solubilizing efficiency of K4 strain was 140% and K7 was 173.9% for P. However, the solubilizing efficiencies of K4 and K7 were 160% and 138.46% for Zn and 160% and 466% for K, respectively. The field trials were performed for two consecutive years, and growth and yield related parameters were measured for evaluation of the effect of P, K and Zn-solubilizing fungal strains on the crop. All the treatments showed a significant (P < 0.05) increase in growth and yield of M. uniflorum plants over uninoculated control; however, the best treatment was found to be soil inoculated with P. chrysogenum K4 + A. niger K7 in which the yield was enhanced by 71% over control. Thus, the co-inoculation of K4 and K7 strains showed a great potential to improve the growth and yield of plants. Both the fungal strains simultaneously solubilized three important nutritional elements in soil, which is a rare trait. Moreover, the capacity of these fungal strains to enhance the plant root nodulation and microbial count in soil makes the co-inoculation practice quite beneficial for sustainable agriculture.
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Affiliation(s)
- Jyoti Rawat
- Biochemical Engineering Department, B.T. Kumaon Institute of Technology, Dwarahat, India
- Department of Biotechnology, Sir J. C. Bose Technical Campus Bhimtal, Kumaun University Nainital, Nainital, India
| | - Jyoti Saxena
- Biochemical Engineering Department, B.T. Kumaon Institute of Technology, Dwarahat, India
| | - Pankaj Sanwal
- Biochemical Engineering Department, B.T. Kumaon Institute of Technology, Dwarahat, India
| | - Naga Raju Maddela
- Departamento de Ciencias Biológicas, Facultad de Ciencias de la Salud, Universidad Técnica de Manabí, Portoviejo, Ecuador
| | - Lata Nain
- Microbiology Division, Indian Agriculture Research Institute, New Delhi, India
| | - Ram Prasad
- Department of Botany, Mahatma Gandhi Central University, Motihari, 845401, India.
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Liu Z, Wu Z, Tian F, Liu X, Li T, He Y, Li B, Zhang Z, Yu B. Phosphate-solubilizing microorganisms regulate the release and transformation of phosphorus in biochar-based slow-release fertilizer. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 869:161622. [PMID: 36649772 DOI: 10.1016/j.scitotenv.2023.161622] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 01/02/2023] [Accepted: 01/11/2023] [Indexed: 06/17/2023]
Abstract
Coupling phosphate-solubilizing microorganisms (PSM) can improve the availability of phosphorous (P) in biochar-based slow-release P fertilizers (BPF). However, the mechanism in release and transformation of P in BPF regulated by PSM is still unclear. Herein, the biocompatibility and the adhesion behaviors of BPF and PSM (Enterobacter hormaechei Rs-198) in soil were firstly studied, and a 90 days' laboratory-scale soil incubation experiment of BPF and Rs-198 was performed to study the transformation of P of BPF. The results show that BPF has a good biocompatibility for Rs-198 due to its low aromaticity, graphitization and free radicals' content (0.084 mg/g). Rs-198 are adhered to the surface of BPF in soil due to the high negative secondary energy minimum and low total interaction energy between Rs-198 and BPF. Available P in the incubation of BPF and Rs-198 (BR treatment) is significantly higher than that of the incubation of BPF (BF treatment) at initial 60 days. However, the content of available P in BR treatment is much lower compared with that in BF treatment on day 90, which is attributed to the entrapment of released P from BPF by Rs-198 and the formation of polyphosphate (polyP) rather than bound with soil mineral. Overall, this study presents new insights into the transformation of P in BPF regulated by PSM.
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Affiliation(s)
- Zhongwang Liu
- School of Environmental and Chemical Engineering, Xi'an Key Laboratory of Textile Chemical Engineering' Auxiliaries, Xi'an Polytechnic University, Xi'an 710048, PR China; School of Chemistry and Chemical Engineering/Key Lab. for Green Processing of Chemical Engineering of Xinjiang Bingtuan, Shihezi University, Shihezi 832003, PR China; School of Agriculture, Shenzhen Campus of Sun Yat-sen University, Shenzhen, Guangdong 518107, China
| | - Zhansheng Wu
- School of Environmental and Chemical Engineering, Xi'an Key Laboratory of Textile Chemical Engineering' Auxiliaries, Xi'an Polytechnic University, Xi'an 710048, PR China.
| | - Fei Tian
- School of Environmental and Chemical Engineering, Xi'an Key Laboratory of Textile Chemical Engineering' Auxiliaries, Xi'an Polytechnic University, Xi'an 710048, PR China
| | - Xiaochen Liu
- School of Environmental and Chemical Engineering, Xi'an Key Laboratory of Textile Chemical Engineering' Auxiliaries, Xi'an Polytechnic University, Xi'an 710048, PR China
| | - Tao Li
- School of Environmental and Chemical Engineering, Xi'an Key Laboratory of Textile Chemical Engineering' Auxiliaries, Xi'an Polytechnic University, Xi'an 710048, PR China
| | - Yanhui He
- School of Environmental and Chemical Engineering, Xi'an Key Laboratory of Textile Chemical Engineering' Auxiliaries, Xi'an Polytechnic University, Xi'an 710048, PR China
| | - Beibei Li
- School of Chemistry and Chemical Engineering/Key Lab. for Green Processing of Chemical Engineering of Xinjiang Bingtuan, Shihezi University, Shihezi 832003, PR China
| | - Ziyan Zhang
- School of Environmental and Chemical Engineering, Xi'an Key Laboratory of Textile Chemical Engineering' Auxiliaries, Xi'an Polytechnic University, Xi'an 710048, PR China
| | - Bing Yu
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 311300, PR China; School of Environment and Resources, Zhejiang A&F University, Hangzhou 311300, PR China.
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Zhang J, Han X, Su Y, Staehelin C, Xu C. T-DNA insertion mutagenesis in Penicillium brocae results in identification of an enolase gene mutant impaired in secretion of organic acids and phosphate solubilization. MICROBIOLOGY (READING, ENGLAND) 2023; 169. [PMID: 37068121 DOI: 10.1099/mic.0.001325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
Penicillium brocae strain P6 is a phosphate-solubilizing fungus isolated from farmland in Guangdong Province, China. To gain better insights into the phosphate solubilization mechanisms of strain P6, a T-DNA insertion population containing approximately 4500 transformants was generated by Agrobacterium tumefaciens-mediated transformation. The transformation procedure was optimized by using a Hybond N membrane for co-cultivation of A. tumefaciens and P. brocae. A mutant impaired in phosphate solubilization (named MT27) was obtained from the T-DNA insertion population. Thermal asymmetric interlaced PCR was then used to identify the nucleotide sequences flanking the T-DNA insertion site. The T-DNA in MT27 was inserted into the fourth exon of an enolase gene, which shows 90.8 % nucleotide identity with enolase mRNA from Aspergillus neoniger. Amino acid sequence homology analysis indicated that the enolase is well conserved among filamentous fungi and Saccharomyces cerevisiae. Complementation tests with the MT27 mutant confirmed that the enolase gene is involved in phosphate solubilization. Analysis of organic acids in culture supernatants indicated reduced levels of oxalic acid and lactic acid for the MT27 mutant compared to the parent strain P6 or the complementation strain. In conclusion, we suggest that the identified enolase gene of P. brocae is involved in production of specific organic acids, which, when secreted, act as phosphate solubilizing agents.
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Affiliation(s)
- Juntao Zhang
- Guangzhou Institute of Forestry and Landscape Architecture, Guangzhou 510405, PR China
| | - Xiaoge Han
- School of Ecological Environment Technology, Guangdong Industry Polytechnic, Nanhai Campus, Foshan 528225, PR China
| | - Yang Su
- Guangzhou Institute of Forestry and Landscape Architecture, Guangzhou 510405, PR China
| | - Christian Staehelin
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, PR China
| | - Changchao Xu
- Guangzhou Institute of Forestry and Landscape Architecture, Guangzhou 510405, PR China
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Vera-Morales M, López Medina SE, Naranjo-Morán J, Quevedo A, Ratti MF. Nematophagous Fungi: A Review of Their Phosphorus Solubilization Potential. Microorganisms 2023; 11:137. [PMID: 36677427 PMCID: PMC9867276 DOI: 10.3390/microorganisms11010137] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/20/2022] [Accepted: 12/24/2022] [Indexed: 01/07/2023] Open
Abstract
Nematophagous fungi (NF) are a group of diverse fungal genera that benefit plants. The aim of this review is to increase comprehension about the importance of nematophagous fungi and their role in phosphorus solubilization to favor its uptake in agricultural ecosystems. They use different mechanisms, such as acidification in the medium, organic acids production, and the secretion of enzymes and metabolites that promote the bioavailability of phosphorus for plants. This study summarizes the processes of solubilization, in addition to the mechanisms of action and use of NF on crops, evidencing the need to include innovative alternatives for the implementation of microbial resources in management plans. In addition, it provides information to help understand the effect of NF to make phosphorus available for plants, showing how these biological means promote phosphorus uptake, thus improving productivity and yield.
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Affiliation(s)
- Marcos Vera-Morales
- Escuela de Postgrado, Universidad Nacional de Trujillo, Jr. San Martin 392, Trujillo 13007, Perú
- Escuela Superior Politécnica del Litoral, ESPOL, Centro de Investigaciones Biotecnológicas del Ecuador, CIBE, Campus Gustavo Galindo Km. 30.5 vía Perimetral, Guayaquil EC090112, Ecuador
| | - Segundo E. López Medina
- Escuela de Postgrado, Universidad Nacional de Trujillo, Jr. San Martin 392, Trujillo 13007, Perú
| | - Jaime Naranjo-Morán
- Laboratorio de Biotecnología Vegetal, Ingeniería en Biotecnología, Facultad Ciencias de la Vida, Campus María Auxiliadora, Universidad Politécnica Salesiana (UPS), Km 19.5 Vía a la Costa, Guayaquil P.O. Box 09-01-2074, Ecuador
| | - Adela Quevedo
- Escuela Superior Politécnica del Litoral, ESPOL, Centro de Investigaciones Biotecnológicas del Ecuador, CIBE, Campus Gustavo Galindo Km. 30.5 vía Perimetral, Guayaquil EC090112, Ecuador
| | - María F. Ratti
- Escuela Superior Politécnica del Litoral, ESPOL, Centro de Investigaciones Biotecnológicas del Ecuador, CIBE, Campus Gustavo Galindo Km. 30.5 vía Perimetral, Guayaquil EC090112, Ecuador
- Escuela Superior Politécnica del Litoral, ESPOL, Facultad de Ciencias de la Vida, FCV, Campus Gustavo Galindo Km. 30.5 vía Perimetral, Guayaquil EC090608, Ecuador
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Molecular Characterization and Mineralizing Potential of Phosphorus Solubilizing Bacteria Colonizing Common Bean ( Phaseolus vulgaris L.) Rhizosphere in Western Kenya. Int J Microbiol 2023; 2023:6668097. [PMID: 36908981 PMCID: PMC9995209 DOI: 10.1155/2023/6668097] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 02/06/2023] [Accepted: 02/14/2023] [Indexed: 03/06/2023] Open
Abstract
Phosphorus solubilizing bacteria (PSB) are a category of microbes that transform insoluble phosphates in soil into soluble forms that crops can utilize. Phosphorus in natural soils is abundant but poorly soluble. Hence, introducing PSB is a safer way of improving its solubility. The aim of this study was to genetically characterize and determine the mineralization capability of selected PSB colonizing rhizospheres of common beans in Western Kenya. Seven potential phosphorus solubilizing bacteria (PSB) were isolated from various subregions of Western Kenya. 16S ribosomal RNA gene sequencing and National Center for Biotechnology Information (NCBI), Basic Local Alignment Search Tool (BLAST) identified the isolates. The phosphate solubilization potential of the isolates was evaluated under agar and broth medium of National Botanical Research Institute's phosphate (NBRIP) supplemented with tricalcium calcium phosphate (TCP). Identified isolates were as follows: KK3 as Enterobacter mori, B5 (KB5) as Pseudomonas kribbensis, KV1 as Enterobacter asburiae, KB3 as Enterobacter mori, KK1 as Enterobacter cloacae, KBU as Enterobacter tabaci, and KB2 as Enterobacter bugandensis. The strains B5 and KV1 were the most effective phosphorus solubilizers with 4.16 and 3.64 indices, respectively. The microbes converted total soluble phosphate concentration in broth medium which was 1395 and 1471 P μg/mL, respectively. The least performing isolate was KBU with a 2.34 solubility index. Significant (p ≤ 0.05) differences in plant biomass for Rose coco and Mwitemania bean varieties were observed under inoculation with isolates B5 and KV1. PSB isolates found in common bean rhizospheres exhibited molecular variations and isolates B5 and KV1 are the potential in solving the insufficiency of phosphorus for sustainable crop production.
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Bacteria Associated with the Roots of Common Bean ( Phaseolus vulgaris L.) at Different Development Stages: Diversity and Plant Growth Promotion. Microorganisms 2022; 11:microorganisms11010057. [PMID: 36677349 PMCID: PMC9861878 DOI: 10.3390/microorganisms11010057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 12/16/2022] [Accepted: 12/21/2022] [Indexed: 12/29/2022] Open
Abstract
Current agricultural methodologies are vulnerable to erratic climate and are dependent on cost-intensive fertilization to ensure high yields. Sustainable practices should be pursued to ensure food security. Phaseolus vulgaris L. is one of the most produced legumes worldwide and may be an alternative to reduce the environmental impact of meat production as a reliable source of high-quality protein. Plant growth-promoting rhizobacteria (PGPR) are emerging as a sustainable option to increase agricultural production. To understand the dynamics between plants and microorganisms, the culturable microbiota of bean roots was isolated and identified at distinct stages of plant development (early and late vegetative growth, flowering, and pod) and root compartments (rhizoplane, endosphere, and nodules). Diversity and abundance of bacteria associated with root compartments differed throughout the plant life cycle. Bacterial plant growth promotion (PGP) and protection abilities (indole-3-acetic acid production, siderophore synthesis, and antifungal activity) were assessed and associated with plant phenology, demonstrating that among the bacteria associated with plant roots, several strains had an active role in the response to plant biological needs at each stage. Several strains stood out for their ability to display one or more PGP traits, being excellent candidates for efficient stage-specific biostimulants for application in precision agriculture.
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Singh AK, Gupta RK, Purohit HJ, Khardenavis AA. Genomic characterization of denitrifying methylotrophic Pseudomonas aeruginosa strain AAK/M5 isolated from municipal solid waste landfill soil. World J Microbiol Biotechnol 2022; 38:140. [PMID: 35705700 DOI: 10.1007/s11274-022-03311-7] [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: 11/10/2021] [Accepted: 05/15/2022] [Indexed: 11/26/2022]
Abstract
Municipal landfills are known for methane production and a source of nitrate pollution leading to various environmental issues. Therefore, this niche was selected for the isolation of one-carbon (C1) utilizing bacteria with denitrifying capacities using anaerobic enrichment on nitrate mineral salt medium supplemented with methanol as carbon source. Eight axenic cultures were isolated of which, isolate AAK/M5 demonstrated the highest methanol removal (73.28%) in terms of soluble chemical oxygen demand and methane removal (41.27%) at the expense of total nitrate removal of 100% and 33% respectively. The whole genome characterization with phylogenomic approach suggested that the strain AAK/M5 could be assigned to Pseudomonas aeruginosa with close neighbours as type strains DVT779, AES1M, W60856, and LES400. The circular genome annotation showed the presence of complete set of genes essential for methanol utilization and complete denitrification process. The study demonstrates the potential of P. aeruginosa strain AAK/M5 in catalysing methane oxidation thus serving as a methane sink vis-à-vis utilization of nitrate. Considering the existence of such bacteria at landfill site, the study highlights the need to develop strategies for their enrichment and designing of efficient catabolic activity for such environments.
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Affiliation(s)
- Ashish Kumar Singh
- Environmental Biotechnology and Genomics Division, CSIR-National Environmental Engineering Research Institute, Nehru Marg, Nagpur, Maharashtra, 440020, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Rakesh Kumar Gupta
- Environmental Biotechnology and Genomics Division, CSIR-National Environmental Engineering Research Institute, Nehru Marg, Nagpur, Maharashtra, 440020, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Hemant J Purohit
- Environmental Biotechnology and Genomics Division, CSIR-National Environmental Engineering Research Institute, Nehru Marg, Nagpur, Maharashtra, 440020, India
| | - Anshuman Arun Khardenavis
- Environmental Biotechnology and Genomics Division, CSIR-National Environmental Engineering Research Institute, Nehru Marg, Nagpur, Maharashtra, 440020, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.
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Inoculation with Plant Growth-Promoting Bacteria to Reduce Phosphate Fertilization Requirement and Enhance Technological Quality and Yield of Sugarcane. Microorganisms 2022; 10:microorganisms10010192. [PMID: 35056643 PMCID: PMC8781176 DOI: 10.3390/microorganisms10010192] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/10/2022] [Accepted: 01/11/2022] [Indexed: 02/05/2023] Open
Abstract
Phosphorus (P) is a critical nutrient for high sugarcane yields throughout its cultivation cycles, however, a higher amount of P becomes rapidly unavailable to plants due to its adsorption to soil colloids. Some plant growth-promoting bacteria (PGPBs) may be able to enhance P availability to plants and produce phytohormones that contribute to crop development, quality, and yield. Thus, this study aimed to evaluate leaf concentrations of nitrogen (N) and P, yield, and technological quality of sugarcane as a function of different levels of phosphate fertilization associated with inoculation of PGPBs. The experiment was carried out at Ilha Solteira, São Paulo—Brazil. The experimental design was randomized blocks with three replications, consisting of five phosphorus rates (0, 25, 50, 75, and 100% of the recommended P2O5 rate) and eight inoculations, involving three species of PGPBs (Azospirillum brasilense, Bacillus subtilis, and Pseudomonas fluorescens) which were applied combined or in a single application into the planting furrow of RB92579 sugarcane variety. The inoculation of B. subtilis and P. fluorescens provided a higher concentration of leaf P in sugarcane. The P2O5 rates combined with inoculation of bacteria alter technological variables and stalk yield of sugarcane. The excess and lack of phosphate fertilizer is harmful to sugarcane cultivation, regardless of the use of growth-promoting bacteria. We recommend the inoculation with A. brasilense + B. subtilis associated with 45 kg ha−1 of P2O5 aiming at greater stalk yield. This treatment also increases sugar yield, resulting in a savings of 75% of the recommended P2O5 rate, thus being a more efficient and sustainable alternative for reducing sugarcane crop production costs.
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Katiyar P, Kumar S, Arora NK. Interactions of Nitrogen-Fixing Bacteria and Cereal Crops: An Important Dimension. NITROGEN FIXING BACTERIA: SUSTAINABLE GROWTH OF NON-LEGUMES 2022:169-194. [DOI: 10.1007/978-981-19-4906-7_8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/26/2024]
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12
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Plant Growth-Promoting Rhizobacteria as a Green Alternative for Sustainable Agriculture. SUSTAINABILITY 2021. [DOI: 10.3390/su131910986] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Environmental stress is a major challenge for sustainable food production as it reduces yield by generating reactive oxygen species (ROS) which pose a threat to cell organelles and biomolecules such as proteins, DNA, enzymes, and others, leading to apoptosis. Plant growth-promoting rhizobacteria (PGPR) offers an eco-friendly and green alternative to synthetic agrochemicals and conventional agricultural practices in accomplishing sustainable agriculture by boosting growth and stress tolerance in plants. PGPR inhabit the rhizosphere of soil and exhibit positive interaction with plant roots. These organisms render multifaceted benefits to plants by several mechanisms such as the release of phytohormones, nitrogen fixation, solubilization of mineral phosphates, siderophore production for iron sequestration, protection against various pathogens, and stress. PGPR has the potential to curb the adverse effects of various stresses such as salinity, drought, heavy metals, floods, and other stresses on plants by inducing the production of antioxidant enzymes such as catalase, peroxidase, and superoxide dismutase. Genetically engineered PGPR strains play significant roles to alleviate the abiotic stress to improve crop productivity. Thus, the present review will focus on the impact of PGPR on stress resistance, plant growth promotion, and induction of antioxidant systems in plants.
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Saeed Q, Xiukang W, Haider FU, Kučerik J, Mumtaz MZ, Holatko J, Naseem M, Kintl A, Ejaz M, Naveed M, Brtnicky M, Mustafa A. Rhizosphere Bacteria in Plant Growth Promotion, Biocontrol, and Bioremediation of Contaminated Sites: A Comprehensive Review of Effects and Mechanisms. Int J Mol Sci 2021; 22:10529. [PMID: 34638870 PMCID: PMC8509026 DOI: 10.3390/ijms221910529] [Citation(s) in RCA: 105] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 09/23/2021] [Accepted: 09/27/2021] [Indexed: 01/23/2023] Open
Abstract
Agriculture in the 21st century is facing multiple challenges, such as those related to soil fertility, climatic fluctuations, environmental degradation, urbanization, and the increase in food demand for the increasing world population. In the meanwhile, the scientific community is facing key challenges in increasing crop production from the existing land base. In this regard, traditional farming has witnessed enhanced per acre crop yields due to irregular and injudicious use of agrochemicals, including pesticides and synthetic fertilizers, but at a substantial environmental cost. Another major concern in modern agriculture is that crop pests are developing pesticide resistance. Therefore, the future of sustainable crop production requires the use of alternative strategies that can enhance crop yields in an environmentally sound manner. The application of rhizobacteria, specifically, plant growth-promoting rhizobacteria (PGPR), as an alternative to chemical pesticides has gained much attention from the scientific community. These rhizobacteria harbor a number of mechanisms through which they promote plant growth, control plant pests, and induce resistance to various abiotic stresses. This review presents a comprehensive overview of the mechanisms of rhizobacteria involved in plant growth promotion, biocontrol of pests, and bioremediation of contaminated soils. It also focuses on the effects of PGPR inoculation on plant growth survival under environmental stress. Furthermore, the pros and cons of rhizobacterial application along with future directions for the sustainable use of rhizobacteria in agriculture are discussed in depth.
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Affiliation(s)
- Qudsia Saeed
- College of Natural Resources and Environment, Northwest Agriculture and Forestry University, Yangling 712100, China;
| | - Wang Xiukang
- College of Life Sciences, Yan’an University, Yan’an 716000, China
| | - Fasih Ullah Haider
- College of Resources and Environmental Sciences, Gansu Agricultural University, Lanzhou 730070, China;
| | - Jiří Kučerik
- Institute of Chemistry and Technology of Environmental Protection, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic; (J.K.); (M.B.)
| | - Muhammad Zahid Mumtaz
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Defense Road, Lahore 54000, Pakistan;
| | - Jiri Holatko
- Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of AgriSciences, Mendel University in Brno, Zemedelska 1, 613 00 Brno, Czech Republic; (J.H.); (A.K.)
| | - Munaza Naseem
- Institute of Soil and Environmental Science, University of Agriculture Faisalabad, Faisalabad 38040, Pakistan; (M.N.); (M.N.)
| | - Antonin Kintl
- Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of AgriSciences, Mendel University in Brno, Zemedelska 1, 613 00 Brno, Czech Republic; (J.H.); (A.K.)
- Agricultural Research, Ltd., Zahradni 400/1, 664 41 Troubsko, Czech Republic
| | - Mukkaram Ejaz
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China;
| | - Muhammad Naveed
- Institute of Soil and Environmental Science, University of Agriculture Faisalabad, Faisalabad 38040, Pakistan; (M.N.); (M.N.)
| | - Martin Brtnicky
- Institute of Chemistry and Technology of Environmental Protection, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic; (J.K.); (M.B.)
- Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of AgriSciences, Mendel University in Brno, Zemedelska 1, 613 00 Brno, Czech Republic; (J.H.); (A.K.)
| | - Adnan Mustafa
- Biology Center CAS, SoWa RI, Na Sadkach 7, 370 05 České Budějovice, Czech Republic
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Zhang H, Han L, Jiang B, Long C. Identification of a phosphorus-solubilizing Tsukamurella tyrosinosolvens strain and its effect on the bacterial diversity of the rhizosphere soil of peanuts growth-promoting. World J Microbiol Biotechnol 2021; 37:109. [PMID: 34057641 DOI: 10.1007/s11274-021-03078-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 05/25/2021] [Indexed: 12/16/2022]
Abstract
Phosphate solubilizing microorganisms widely exist in plant rhizosphere soil, but report about the P solubilization and multiple growth-promoting properties of rare actinomycetes are scarce. In this paper, a phosphate solubilizing Tsukamurella tyrosinosolvens P9 strain was isolated from the rhizosphere soil of tea plants. Phosphorus-dissolving abilities of this strain were different under different carbon and nitrogen sources, the soluble phosphorus content was 442.41 mg/L with glucose and potassium nitrate as nutrient sources. The secretion of various organic acids, such as lactic acid, maleic acid, oxalic acid, etc., was the main mechanism for P solubilization and pH value in culture was very significant negative correlation with soluble P content. In addition, this strain had multiple growth-promoting characteristics with 37.26 μg/mL of IAA and 72.01% of siderophore relative content. Under pot experiments, P9 strain improved obviously the growth of peanut seedlings. The bacterial communities of peanut rhizoshpere soil were assessed after inoculated with P9 strain. It showed that there was no significant difference in alpha-diversity indices between the inoculation and control groups, but the P9 treatment group changed the composition of bacterial communities, which increased the relative abundance of beneficial and functional microbes, which relative abundances of Chitinophagaceae at the family level, and of Flavihumibacter, Ramlibacter and Microvirga at the genus level, were all siginificant increased. Specially, Tsukamurella tyrosinosolvens were only detected in the rhizosphere of the inoculated group. This study not only founded growth-promoting properties of T. tyrosinosolvens P9 strain and its possible phosphate solublizing mechanism, but also expected to afford an excellent strain resource in biological fertilizers.
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Affiliation(s)
- Hong Zhang
- College of Life SciencesKey Laborary of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education)Collaborative Innovation Center for Mountain Ecology & Agro-Bioengineering (CICMEAB)Institute of Agro-Bioengineering, Guizhou University, Guiyang, 550025, Guizhou, China
| | - Lizhen Han
- College of Life SciencesKey Laborary of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education)Collaborative Innovation Center for Mountain Ecology & Agro-Bioengineering (CICMEAB)Institute of Agro-Bioengineering, Guizhou University, Guiyang, 550025, Guizhou, China.
| | - Biao Jiang
- College of Life SciencesKey Laborary of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education)Collaborative Innovation Center for Mountain Ecology & Agro-Bioengineering (CICMEAB)Institute of Agro-Bioengineering, Guizhou University, Guiyang, 550025, Guizhou, China
| | - Changmei Long
- College of Life SciencesKey Laborary of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education)Collaborative Innovation Center for Mountain Ecology & Agro-Bioengineering (CICMEAB)Institute of Agro-Bioengineering, Guizhou University, Guiyang, 550025, Guizhou, China
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Rojo F. A new global regulator that facilitates the co-metabolization of polyaromatic hydrocarbons and other nutrients in Novosphingobium. Environ Microbiol 2021; 23:2875-2877. [PMID: 33887792 DOI: 10.1111/1462-2920.15527] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 04/12/2021] [Indexed: 11/26/2022]
Abstract
In an article in this issue of Environmental Microbiology, Segura et al. report the identification of an unusual global regulator in Novosphingobium sp. HR1a, a metabolically versatile bacterial strain isolated from the rhizosphere able to assimilate a wide range of polyaromatic hydrocarbons (PAHs). Physiological and transcriptomic assays suggest that this regulator, named PahT, activates the expression of genes involved in the assimilation of PAHs, and of compounds such as sugars and acetate, facilitating their co-metabolism. This effect is the opposite to the carbon catabolite repression strategy that allows metabolically versatile bacteria to favour the use of some compounds over others. PahT was found to stimulate sugar uptake and metabolization in the presence and absence of PAHs and to facilitate microaerobic respiration if PAHs were present. A survey of the genomes of several Sphingomonadaceae members showed that PahT is not present in all strains of this family, but that it is strongly associated with PAH degradation genes. Since not all PAH-degrading strains contain pahT, it seems that PahT is not essential for PAH degradation but likely provides a selective advantage to PAH-degrading strains in environments such as the rhizosphere where other potential carbon sources are available.
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Affiliation(s)
- Fernando Rojo
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, CSIC, Campus UAM, Cantoblanco, Madrid, 28049, Spain
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Tian J, Ge F, Zhang D, Deng S, Liu X. Roles of Phosphate Solubilizing Microorganisms from Managing Soil Phosphorus Deficiency to Mediating Biogeochemical P Cycle. BIOLOGY 2021; 10:158. [PMID: 33671192 PMCID: PMC7922199 DOI: 10.3390/biology10020158] [Citation(s) in RCA: 75] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 02/08/2021] [Accepted: 02/12/2021] [Indexed: 11/16/2022]
Abstract
Phosphorus (P) is a vital element in biological molecules, and one of the main limiting elements for biomass production as plant-available P represents only a small fraction of total soil P. Increasing global food demand and modern agricultural consumption of P fertilizers could lead to excessive inputs of inorganic P in intensively managed croplands, consequently rising P losses and ongoing eutrophication of surface waters. Despite phosphate solubilizing microorganisms (PSMs) are widely accepted as eco-friendly P fertilizers for increasing agricultural productivity, a comprehensive and deeper understanding of the role of PSMs in P geochemical processes for managing P deficiency has received inadequate attention. In this review, we summarize the basic P forms and their geochemical and biological cycles in soil systems, how PSMs mediate soil P biogeochemical cycles, and the metabolic and enzymatic mechanisms behind these processes. We also highlight the important roles of PSMs in the biogeochemical P cycle and provide perspectives on several environmental issues to prioritize in future PSM applications.
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Affiliation(s)
- Jiang Tian
- Department of Chemical Engineering, Xiangtan University, Xiangtan 411105, China;
- Department of Environmental Science and Engineering, College of Environment and Resources, Xiangtan University, Xiangtan 411105, China;
| | - Fei Ge
- Department of Environmental Science and Engineering, College of Environment and Resources, Xiangtan University, Xiangtan 411105, China;
| | - Dayi Zhang
- School of Environment, Tsinghua University, Beijing 100084, China;
| | - Songqiang Deng
- Research Institute for Environmental Innovation (Tsinghua–Suzhou), Suzhou 215163, China;
| | - Xingwang Liu
- Department of Environmental Science and Engineering, College of Environment and Resources, Xiangtan University, Xiangtan 411105, China;
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Ribeiro IDA, Volpiano CG, Vargas LK, Granada CE, Lisboa BB, Passaglia LMP. Use of Mineral Weathering Bacteria to Enhance Nutrient Availability in Crops: A Review. FRONTIERS IN PLANT SCIENCE 2020; 11:590774. [PMID: 33362817 PMCID: PMC7759553 DOI: 10.3389/fpls.2020.590774] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Accepted: 11/26/2020] [Indexed: 05/19/2023]
Abstract
Rock powders are low-cost potential sources of most of the nutrients required by higher plants for growth and development. However, slow dissolution rates of minerals represent an obstacle to the widespread use of rock powders in agriculture. Rhizosphere processes and biological weathering may further enhance mineral dissolution since the interaction between minerals, plants, and bacteria results in the release of macro- and micronutrients into the soil solution. Plants are important agents in this process acting directly in the mineral dissolution or sustaining a wide diversity of weathering microorganisms in the root environment. Meanwhile, root microorganisms promote mineral dissolution by producing complexing ligands (siderophores and organic acids), affecting the pH (via organic or inorganic acid production), or performing redox reactions. Besides that, a wide variety of rhizosphere bacteria and fungi could also promote plant development directly, synergistically contributing to the weathering activity performed by plants. The inoculation of weathering bacteria in soil or plants, especially combined with the use of crushed rocks, can increase soil fertility and improve crop production. This approach is more sustainable than conventional fertilization practices, which may contribute to reducing climate change linked to agricultural activity. Besides, it could decrease the dependency of developing countries on imported fertilizers, thus improving local development.
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Affiliation(s)
- Igor Daniel Alves Ribeiro
- Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Camila Gazolla Volpiano
- Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Luciano Kayser Vargas
- Laboratório de Microbiologia Agrícola, Departamento de Diagnóstico e Pesquisa Agropecuária, Secretaria Estadual da Agricultura, Pecuária e Desenvolvimento Rural, Porto Alegre, Brazil
| | | | - Bruno Brito Lisboa
- Laboratório de Microbiologia Agrícola, Departamento de Diagnóstico e Pesquisa Agropecuária, Secretaria Estadual da Agricultura, Pecuária e Desenvolvimento Rural, Porto Alegre, Brazil
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Khatoon Z, Huang S, Rafique M, Fakhar A, Kamran MA, Santoyo G. Unlocking the potential of plant growth-promoting rhizobacteria on soil health and the sustainability of agricultural systems. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 273:111118. [PMID: 32741760 DOI: 10.1016/j.jenvman.2020.111118] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 07/13/2020] [Accepted: 07/19/2020] [Indexed: 05/06/2023]
Abstract
The concept of soil health refers to specific soil properties and the ability to support and sustain crop growth and productivity, while maintaining long-term environmental quality. The key components of healthy soil are high populations of organisms that promote plant growth, such as the plant growth promoting rhizobacteria (PGPR). PGPR plays multiple beneficial and ecological roles in the rhizosphere soil. Among the roles of PGPR in agroecosystems are the nutrient cycling and uptake, inhibition of potential phytopathogens growth, stimulation of plant innate immunity, and direct enhancement of plant growth by producing phytohormones or other metabolites. Other important roles of PGPR are their environmental cleanup capacities (soil bioremediation). In this work, we review recent literature concerning the diverse mechanisms of PGPR in maintaining healthy conditions of agricultural soils, thus reducing (or eliminating) the toxic agrochemicals dependence. In conclusion, this review provides comprehensive knowledge on the current PGPR basic mechanisms and applications as biocontrol agents, plant growth stimulators and soil rhizoremediators, with the final goal of having more agroecological practices for sustainable agriculture.
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Affiliation(s)
- Zobia Khatoon
- Key Laboratory of Pollution Processes and Environmental Criteria of the Ministry of Education, Key Laboratory of Urban Ecological Environment Rehabilitation and Pollution Control of Tianjin, Numerical Stimulation Group for Water Environment, College of Environmental Science and Engineering Nankai University, Tianjin, 300350, China
| | - Suiliang Huang
- Key Laboratory of Pollution Processes and Environmental Criteria of the Ministry of Education, Key Laboratory of Urban Ecological Environment Rehabilitation and Pollution Control of Tianjin, Numerical Stimulation Group for Water Environment, College of Environmental Science and Engineering Nankai University, Tianjin, 300350, China
| | - Mazhar Rafique
- Department of Soil Science, The University of Haripur, 22630, KPK, Pakistan
| | - Ali Fakhar
- Department of Soil Science, Sindh Agricultural University, Tandojam, Pakistan
| | | | - Gustavo Santoyo
- Genomic Diversity Laboratory, Institute of Biological and Chemical Research, Universidad Michoacana de San Nicolas de Hidalgo, 58030, Morelia, Mexico.
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Efe D. Potential Plant Growth-Promoting Bacteria with Heavy Metal Resistance. Curr Microbiol 2020; 77:3861-3868. [PMID: 32960302 DOI: 10.1007/s00284-020-02208-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 09/09/2020] [Indexed: 11/30/2022]
Abstract
Plant growth-promoting (PGP) bacteria commonly have many strategies to cope with heavy metal toxicity. Heavy metal-resistant PGP bacteria can be used to improve the growth of plants in heavy metal contaminated soils. In this study, the soil samples were collected from the lead-zinc mineral deposits in Gümüşhane Province, Turkey. Nine bacterial isolates were obtained on the nutrient agar medium supplemented with 100 mg/mL zinc and lead. All of the isolates were screened in terms of plant growth-promoting characteristics including production of indole-3-acetic acid and siderophore, nitrogen fixation and phosphate solubilisation. Nine bacteria were identified as Bacillus cereus, Bacillus atrophaeus, Bacillus pumilus, Bacillus amyloliquefaciens, Bacillus tropicus, Bacillus subtilis, Bacillus halotolerans, Bacillus vallismortis, and Enterococcus mundtii by classical and 16S rDNA-PCR assays. In addition, these isolates were evaluated for their response to three heavy metals (lead, zinc, copper) dominant in the soil samples and minimal inhibitory concentration (MIC) of the heavy metals was determined with plate dilution method. Consequently, the bacterial isolates in this study possess plant growth-promoting traits and can ameliorate heavy metal contaminated soil. E. mundtii was reported to be found in heavy metal contaminated soil for the first time. This study is the first report about PGP characteristics (IAA production and phosphate solubilisation) of B. vallismortis.
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Affiliation(s)
- Derya Efe
- Department of Medicinal and Aromatic Plants, Espiye Vocational School, Giresun University, 28000, Giresun, Turkey.
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