Plant Growth-Promoting Activity of Pseudomonas aeruginosa FG106 and Its Ability to Act as a Biocontrol Agent against Potato, Tomato and Taro Pathogens

P. aeruginosa strain FG106 was isolated from the rhizosphere of tomato plants and identified through morphological analysis, 16S rRNA gene sequencing, and whole-genome sequencing. In vitro and in vivo experiments demonstrated that this strain could control several pathogens on tomato, potato, taro, and strawberry. Volatile and non-volatile metabolites produced by the strain are known to adversely affect the tested pathogens. FG106 showed clear antagonism against Alternaria alternata, Botrytis cinerea, Clavibacter michiganensis subsp. michiganensis, Phytophthora colocasiae, P. infestans, Rhizoctonia solani, and Xanthomonas euvesicatoria pv. perforans. FG106 produced proteases and lipases while also inducing high phosphate solubilization, producing siderophores, ammonia, indole acetic acid (IAA), and hydrogen cyanide (HCN) and forming biofilms that promote plant growth and facilitate biocontrol. Genome mining approaches showed that this strain harbors genes related to biocontrol and growth promotion. These results suggest that this bacterial strain provides good protection against pathogens of several agriculturally important plants via direct and indirect modes of action and could thus be a valuable bio-control agent.

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Multiple Plant Growth-Promotion Traits in Endophytic Bacteria Retrieved in the Vegetative Stage From Passionflower

Frontiers in Plant Science ◽

10.3389/fpls.2020.621740 ◽

2021 ◽

Vol 11 ◽

Author(s):

Luis Gabriel Cueva-Yesquén ◽

Marcela Cristina Goulart ◽

Derlene Attili de Angelis ◽

Marcos Nopper Alves ◽

Fabiana Fantinatti-Garboggini

Keyword(s):

Plant Growth ◽

Growth Promotion ◽

Growth Parameters ◽

Vegetative Stage ◽

Rrna Gene ◽

Culturable Bacteria ◽

Bacterial Endophytes ◽

Pgp Traits

Bacteria exhibiting beneficial traits like increasing the bioavailability of essential nutrients and modulating hormone levels in plants are known as plant growth promoting (PGP) bacteria. The occurrence of this specific group of bacteria in the endophytic environment may reflect the decisive role they play in a particular condition. This study aimed to determine the taxonomical diversity of the culturable bacterial endophytes, isolated in the vegetative stage of passionflower (Passiflora incarnata), and assess its potential to promote plant growth by phenotypic and genotypic approaches. The sequencing and phylogenetic analysis of the 16S rRNA gene allowed us to classify 58 bacterial endophytes into nine genera. Bacillus (70.7%) was the most dominant genus, followed by Pseudomonas (8.6%) and Pantoea (6.9%). A few isolates belonged to Rhodococcus and Paenibacillus, whereas the genera Lysinibacillus, Microvirga, Xanthomonas, and Leclercia were represented by only one isolate. The strains were tested for nitrogen fixation, phosphate solubilization, indole-acetic-acid synthesis, and siderophore production. Moreover, PGP related genes (nifH, ipdC, asb, and AcPho) were detected by PCR-based screening. Most of the isolates (94.8%) displayed a potential for at least one of the PGP traits tested by biochemical assays or PCR-based screening. Nine strains were selected based on results from both approaches and were evaluated for boosting the Cape gooseberry (Physalis peruviana) germination and growth. All tested isolates improved germination in vitro, and the majority (78%) increased growth parameters in vivo. The results suggested that most of culturable bacteria inhabiting P. incarnata in the vegetative stage could be used as probiotics for agricultural systems. Besides, their occurrence may be associated with specific physiological needs typical of this development stage.

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Characterization and Evaluation of Bacillus siamensis Isolate for its Growth Promoting Potential in Tomato

Agriculture (Pol nohospodárstvo) ◽

10.2478/agri-2019-0005 ◽

2019 ◽

Vol 65 (2) ◽

pp. 42-50 ◽

Cited By ~ 2

Author(s):

Amanul Islam ◽

Shahinur Kabir ◽

Abul Khair

Keyword(s):

Growth Promotion ◽

16S Rrna Gene Sequencing ◽

Rrna Gene ◽

Growth Enhancement ◽

Sequencing Data ◽

Fresh Weight ◽

Tomato Cultivars ◽

Rrna Gene Sequencing

Abstract In quest of prospective rizospheric bacteria of agricultural importance, one of the isolates from bean (Lablab niger Medikus) was identified as Bacillus siamensis based on morphological, biochemical and 16S rRNA gene sequencing data. Study was carried out to evaluate growth promotion of two tomato cultivars, in vitro and in vivo. Experiments conducted for two consecutive years, following seed treatments revealed that the bacterial isolate increased plant height by 14.66‒15.68%, shoot fresh weight by 34.5‒65.09% and root fresh weight by 75.3‒92.48% over the non-treated control. The bacterial strain showed encouraging results for plant growth promotion in pot study and hence may be useful for the growth enhancement of tomato plant.

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Root Bacteria Recruited by Phragmites australis in Constructed Wetlands Have the Potential to Enhance Azo-Dye Phytodepuration

Microorganisms ◽

10.3390/microorganisms7100384 ◽

2019 ◽

Vol 7 (10) ◽

pp. 384 ◽

Cited By ~ 7

Author(s):

Valentina Riva ◽

Francesca Mapelli ◽

Evdokia Syranidou ◽

Elena Crotti ◽

Redouane Choukrallah ◽

...

Keyword(s):

Plant Growth ◽

Phragmites Australis ◽

Textile Industry ◽

Azo Dye ◽

Growth Promotion ◽

Wide Spectrum ◽

Reactive Black 5 ◽

Potential Use

The microbiome associated with plants used in phytodepuration systems can boost plant growth and services, especially in ecosystems dealing with recalcitrant compounds, hardly removed via traditional wastewater (WW) treatments, such as azo-dyes used in textile industry. In this context, we aimed to study the cultivable microbiome selected by Phragmites australis plants in a Constructed Wetland (CW) in Morocco, in order to obtain candidate inoculants for the phytodepuration of azo-dye contaminated WW. A collection of 152 rhizospheric and endophytic bacteria was established. The strains were phylogenetically identified and characterized for traits of interest in the phytodepuration context. All strains showed Plant Growth Promotion potential in vitro and 67% of them significantly improved the growth of a model plant in vivo compared to the non bacterized control plants. Moreover, most of the isolates were able to grow in presence of several model micropollutants typically found in WW, indicating their potential use in phytodepuration of a wide spectrum of effluents. The six most promising strains of the collection were tested in CW microcosms alone or as consortium: the consortium and two single inocula demonstrated to significantly increase the removal of the model azo-dye Reactive Black 5 compared to the non bacterized controls.

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Plant Growth Promotion Potential Is Equally Represented in Diverse Grapevine Root-Associated Bacterial Communities from Different Biopedoclimatic Environments

BioMed Research International ◽

10.1155/2013/491091 ◽

2013 ◽

Vol 2013 ◽

pp. 1-17 ◽

Cited By ~ 27

Author(s):

Ramona Marasco ◽

Eleonora Rolli ◽

Marco Fusi ◽

Ameur Cherif ◽

Ayman Abou-Hadid ◽

...

Keyword(s):

Environmental Factors ◽

Plant Growth ◽

Bacterial Communities ◽

Growth Promotion ◽

Rrna Gene ◽

Similar Distribution ◽

Bacterial Assemblage ◽

Pgp Traits ◽

Associated Bacteria

Plant-associated bacteria provide important services to host plants. Environmental factors such as cultivar type and pedoclimatic conditions contribute to shape their diversity. However, whether these environmental factors may influence the plant growth promoting (PGP) potential of the root-associated bacteria is not widely understood. To address this issue, the diversity and PGP potential of the bacterial assemblage associated with the grapevine root system of different cultivars in three Mediterranean environments along a macrotransect identifying an aridity gradient were assessed by culture-dependent and independent approaches. According to 16S rRNA gene PCR-DGGE, the structure of endosphere and rhizosphere bacterial communities was highly diverse (P=0.03) and was associated with a cultivar/latitudinal/climatic effect. Despite being diverse, the bacterial communities associated with Egyptian grapevines shared a higher similarity with the Tunisian grapevines than those cultivated in North Italy. A similar distribution, according to the cultivar/latitude/aridity gradients, was observed for the cultivable bacteria. Many isolates (23%) presentedin vitromultiple stress resistance capabilities and PGP activities, the most frequent being auxin synthesis (82%), insoluble phosphate solubilisation (61%), and ammonia production (70%). The comparable numbers and types of potential PGP traits among the three different environmental settings indicate a strong functional homeostasis of beneficial bacteria associated with grape root.

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Seed-Biopriming of Durum Wheat with Diazotrophic Plant Browth Promoting Bacteria (PGPB) Enhanced Tolerance to Fusarium Head Blight (FHB) and Salinity Stress

10.21203/rs.2.16636/v1 ◽

2019 ◽

Author(s):

Adel Hadj Brahim ◽

Mouna Jlidi ◽

Lobna Daoud ◽

Manel Ben-Ali ◽

Asmahen Akremi ◽

...

Keyword(s):

Plant Growth ◽

Durum Wheat ◽

Abiotic Stresses ◽

Growth Promotion ◽

Head Blight ◽

Biotic And Abiotic Stresses ◽

Plant Growth Promoting ◽

Seed Biopriming

Abstract Background The use of bioinoculants based on plant growth-promoting bacteria (PGPB) to promote plant growth under biotic and abiotic stresses is in full expansion. To our knowledge much work has not been, thus far, done on seed-biopriming of durum wheat for tolerance to biotic and abiotic stresses. In the present work, we report detailed account of the effectiveness a potent bacterial strain with proven plant growth-promoting ability and antimicrobial activity. The isolate was selected following screening of several bacterial strains isolated from halophytes that grow in a coastal saline soil in Tunisia for their role in enhancing durum wheat tolerance to both salinity stress and head blight disease.Results Accordingly, Bacillus strains MA9, MA14, MA17 and MA19 were found to have PGPB characteristics as they produced indole-3-acetic acid, siderophores and lytic enzymes, fixed free atmospheric nitrogen, and solubilized inorganic phosphate, in vitro . The in vivo study that involved in planta inoculation assays under control (25 mM NaCl) and stress (125 mM NaCl) conditions indicated that all PGPB strains significantly ( P < 0.05) increased the total plant length, dry weight, root area, seed weight, nitrogen, protein and total mineral content. On the other hand, strain MA17 reduced Fusarium Head Blight (FHB) disease incidence in wheat explants by 64.5%, showing that the strain has antifungal activity as was also displayed by in vitro inhibition study.Conclusions Both in vitro and in vivo studies showed that MA9, MA14 MA9, MA14, MA17 and MA19 strains were able to play the PGPB role. Yet, biopriming with Bacillus strain MA17 offered the highest bioprotection against FHB, plant growth promotion, and salinity tolerance. Hence, the MA17 strain should further be evaluated under field condition and formulated for commercial production. Besides, the strain could further be evaluated for its potential role in bioprotection and growth promotion of other crop plants. We believe, the strain has potential to significantly contribute to wheat production in the arid and semi-arid region, especially the salt affected Middle Eastern Region, besides its potential role in improving wheat production under biotic and abiotic stresses in other parts of the world.

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Plant growth promoting endophyte Burkholderia contaminans NZ antagonizes phytopathogen Macrophomina phaseolina through melanin synthesis and pyrrolnitrin inhibition

PLoS ONE ◽

10.1371/journal.pone.0257863 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0257863

Author(s):

Nazia R. Zaman ◽

Umar F. Chowdhury ◽

Rifath N. Reza ◽

Farhana T. Chowdhury ◽

Mrinmoy Sarker ◽

...

Keyword(s):

Plant Growth ◽

Growth Promotion ◽

Genome Mining ◽

Gene Clusters ◽

Macrophomina Phaseolina ◽

Melanin Synthesis ◽

Burkholderia Contaminans ◽

Plant Growth Promoting ◽

Growth Promoting

The endophytic bacterium Burkholderia contaminans NZ was isolated from jute, which is an important fiber-producing plant. This bacterium exhibits significant growth promotion activity in in vivo pot experiments, and like other plant growth-promoting (PGP) bacteria fixes nitrogen, produces indole acetic acid (IAA), siderophore, and 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. B. contaminans NZ is considered to exert a promising growth inhibitory effect on Macrophomina phaseolina, a phytopathogen responsible for infecting hundreds of crops worldwide. This study aimed to identify the possibility of B. contaminans NZ as a safe biocontrol agent and assess its effectiveness in suppressing phytopathogenic fungi, especially M. phaseolina. Co-culture of M. phaseolina with B. contaminans NZ on both solid and liquid media revealed appreciable growth suppression of M. phaseolina and its chromogenic aberration in liquid culture. Genome mining of B. contaminans NZ using NaPDoS and antiSMASH revealed gene clusters that displayed 100% similarity for cytotoxic and antifungal substances, such as pyrrolnitrin. GC-MS analysis of B. contaminans NZ culture extracts revealed various bioactive compounds, including catechol; 9,10-dihydro-12’-hydroxy-2’-methyl-5’-(phenylmethyl)- ergotaman 3’,6’,18-trione; 2,3-dihydro-3,5- dihydroxy-6-methyl-4H-pyran-4-one; 1-(1,6-Dioxooctadecyl)- pyrrolidine; 9-Octadecenamide; and 2- methoxy- phenol. These compounds reportedly exhibit tyrosinase inhibitory, antifungal, and antibiotic activities. Using a more targeted approach, an RP-HPLC purified fraction was analyzed by LC-MS, confirming the existence of pyrrolnitrin in the B. contaminans NZ extract. Secondary metabolites, such as catechol and ergotaman, have been predicted to inhibit melanin synthesis in M. phaseolina. Thus, B. contaminans NZ appears to inhibit phytopathogens by apparently impairing melanin synthesis and other potential biochemical pathways, exhibiting considerable fungistatic activity.

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Characterization of multi-trait plant growth promoting Pseudomonas aeruginosa from chickpea (Cicer arietinum) rhizosphere

Journal of Applied and Natural Science ◽

10.31018/jans.v13i3.2782 ◽

2021 ◽

Vol 13 (3) ◽

pp. 1003-1010

Author(s):

Monika Soni ◽

Kamlesh Choure

Keyword(s):

Pseudomonas Aeruginosa ◽

16S Rrna ◽

Plant Growth ◽

16S Rrna Gene ◽

Cicer Arietinum ◽

Growth Promotion ◽

Gene Sequencing ◽

16S Rrna Gene Sequencing ◽

Rrna Gene ◽

Rrna Gene Sequencing

In the current perusal, 12 isolates of Pseudomonas were segregated by rhizospheric soil of chickpea (Cicer arietinum) of Madhya Pradesh, India. Isolated test organisms were characterized morphologically, biochemically and 16S rRNA gene sequencing. Out of 12, one isolate designated as P4 was identified as Pseudomonas aeruginosa through 16S rRNA gene sequencing, which revealed 100% homology with the strains DSM 50071 and NBRC 12689. The phylogenetic examination was accomplished utilizing MEGA-X to confirm the identity of isolate P4. The nucleotide hierarchy of the 16S rRNA gene from P4 isolate was submitted in the National Center for Biotechnology Information (NCBI) database under gene bank with accession number MT116414. The P4 isolate exhibited multiple plant growth promotion properties like phosphate solubility, indole acetic acid (IAA) production, 1-aminocyclopropane-1-carboxylate (ACC) deaminase, siderophores, ammonia (NH3) and hydrogen cyanide (HCN) activities, and biocontrol activities against phytopathogenic fungi Fusarium oxysporum and Macrophomina phaseolina.

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Enhancement of verticillium wilt resistance in tomato transplants by in vitro co-culture of seedlings with a plant growth promoting rhizobacterium (Pseudomonas sp. strain PsJN)

Canadian Journal of Microbiology ◽

10.1139/w98-017 ◽

1998 ◽

Vol 44 (6) ◽

pp. 528-536 ◽

Cited By ~ 67

Author(s):

V K Sharma ◽

J Nowak

Keyword(s):

Plant Growth ◽

Verticillium Wilt ◽

Plant Growth Promotion ◽

Growth Promotion ◽

Disease Suppression ◽

Pseudomonas Sp ◽

Plant Growth Promoting ◽

Growth Promoting

The potential utilization of a plant growth promoting rhizobacterium, Pseudomonas sp. strain PsJN, to enhance the resistance of tomato transplants to verticillium wilt was investigated. Plant growth and disease development were tested on the disease-susceptible cultivar Bonny Best after Verticillium dahliae infection of tissue culture plantlets bacterized in vitro (by co-culturing with the bacterium) and seedlings bacterized in vivo (after 3 weeks growth in the greenhouse). Significant differences in both disease suppression and plant growth were obtained between in vitro bacterized and nonbacterized (control) plants. The degree of protection afforded by in vitro bacterization depended on the inoculum density of V. dahliae; the best and worst protection occurred at the lowest (103 conidia ·mL-1) and highest (106 conidia ·mL-1) levels, respectively. In contrast, the in vivo bacterized tomatoes did not show plant growth promotion when compared to the nonbacterized control plants. When challenged with Verticillium, significant growth differences between in vivo bacterized plants (26.8% for shoot height) and nonbacterized controls were only seen at the 3rd week after inoculation. Compared with the in vitro inoculation, there was no delay in the verticillium wilt symptom expression, even at the lowest concentration of V. dahliae, by in vivo PsJN inoculation. These results suggest that endophytic colonization of tomato tissues is required for the Verticillium-resistance responses. Plant growth promotion preceeds the disease-resistance responses and may depend on the colonization thresholds and subsequent sensitization of hosts.Key words: Pseudomonas sp., plant growth promoting rhizobacterium, Verticillium dahliae, tomato, colonization, plant growth promotion, disease suppression.

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In vitro and in vivo characterization and strain safety of Lactobacillus reuteri NCIMB 30253 for probiotic applications

Canadian Journal of Microbiology ◽

10.1139/w2012-050 ◽

2012 ◽

Vol 58 (6) ◽

pp. 776-787 ◽

Cited By ~ 7

Author(s):

Imran Sulemankhil ◽

Mathieu Parent ◽

Mitchell Lawrence Jones ◽

Zhenqian Feng ◽

Alain Labbé ◽

...

Keyword(s):

Lactobacillus Reuteri ◽

16S Rrna Gene Sequencing ◽

Human Consumption ◽

Rrna Gene ◽

Sprague Dawley ◽

Dose Study ◽

Clinically Significant ◽

Rrna Gene Sequencing

Lactobacillus reuteri NCIMB 30253 was shown to have potential as a probiotic by reducing the proinflammatory chemokine interleukin-8. Moreover, this strain was evaluated, by in vitro and in vivo techniques, for its safety for human consumption. The identity of the strain was investigated by metabolic profiling and 16S rRNA gene sequencing, and in vitro safety evaluations were performed by molecular and metabolic techniques. Genetic analysis was confirmed by assessing the minimum inhibitory concentration to a panel of antibiotics, showing that the strain was susceptible to 8 antibiotics tested. The ability of the strain to produce potentially harmful by-products and antimicrobial compounds was evaluated, showing that the strain does not produce biogenic amines and does not show bacteriocin activity or reuterin production. A 28-day repeated oral dose study was conducted in normal Sprague–Dawley rats to support the in vivo strain safety. Oral administration of the strain resulted in no changes in general condition and no clinically significant changes to biochemical and haematological markers of safety relative to vehicle control treated animals. This comprehensive assessment of safety of L. reuteri NCIMB 30253 supports the safety of the strain for use as a probiotic.

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Bacteria Isolated from Wastewater Irrigated Agricultural Soils Adapt to Heavy Metal Toxicity While Maintaining Their Plant Growth Promoting Traits

Sustainability ◽

10.3390/su13147792 ◽

2021 ◽

Vol 13 (14) ◽

pp. 7792

Author(s):

Abdul Wahab Ajmal ◽

Saleha Saroosh ◽

Shah Mulk ◽

Muhammad Nadeem Hassan ◽

Humaira Yasmin ◽

...

Keyword(s):

Plant Growth ◽

Agricultural Soils ◽

Culture Media ◽

Growth Promotion ◽

Metal Resistance ◽

Rrna Gene ◽

Gene Sequence Analysis ◽

Plant Growth Promoting ◽

Growth Promoting

The present study explored the plant growth promotion and bioremediation potential of bacteria inhabiting wastewater irrigated agricultural soils. Thirty out of 75 bacterial isolates (40%), 29/75 (39%) and 28/75 (37%) solubilized Zn, K and PO4 during plate essays respectively. Fifty-six percent of the isolates produced siderophores, while 30% released protease in vitro. Seventy-four percent of bacteria resisted Pb, Ni and Cd at various concentrations added to the culture media plates. Sixteen out of 75 (26%) isolates were able to fix N in Nbf medium. Among these 16 N fixers, N fixing nifH, nifD and nifK genes was detected through PCR in 8, 7 and 1 strain respectively using gene specific primers designed in the study with Enterobacter sp. having all three (nifHKD) genes. Isolated bacteria showed resemblance to diverse genera such as Bacillus, Pseudomonas, Enterobacter, Citrobacter, Acinetobacter, Serratia, Klebsiella and Enterococcus based on 16S rRNA gene sequence analysis. In addition to showing the best mineral solubilization and metal resistance potential, Citrobacter sp. and Enterobacter sp. also removed 87%, 79% and 43% and 86%, 78% and 51% of Ni, Cd and Pb, respectively, from aqueous solution. These potent bacteria may be exploited both for bioremediation and biofertilization of wastewater irrigated soils leading to sustainable agriculture.

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