A plant growth-promoting rhizobacteria (PGPR) mixture does not display synergistic effects, likely by biofilm but not growth inhibition

Kang, Yijun; Shen, Min; Yang, Xiaolan; Cheng, Daocheng; Qingxin, Zhao

doi:10.1134/s0026261714050166

Cited by 18 publications

(9 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…RGM 2526 displayed no effect on the germination rate when inoculated alone, being similar to that obtained with the control treatment; there was potentially a synergistic effect when the three isolates were inoculated together, suggesting there could exist others bacterial metabolites that may be influencing the germination process (Figure 4). Other reports have shown that a mixture of microbial strains used as bioinoculants has no effect on plant-growth promotion as some strains can affect or inhibit the growth of other strains in the formulation, thus it is important to check the compatibility of the strains before using them as bioinoculants (Kang et al, 2014).…”

Section: Discussionmentioning

confidence: 99%

Plant growth promoting rhizobacteria from Juan Fernández archipelago improve germination rate of endangered plant Solanum fernandezianum Phil.

Carrasco-Fernández

Guerra

Castro

et al. 2020

Chil. j. agric. res.

View full text Add to dashboard Cite

Robinson Crusoe Island, Chile, has one of the highest densities of endemic plants in the world, however many of its native and endemic species, such as Solanum fernandezianum Phil., are currently declared endangered. Coating the seeds of native plants with locally sourced plant-growth-promoting bacteria can be used as a tool for conservation programs of endangered plant species. Isolation and screening of rhizosphere bacteria from Robinson Crusoe Island resulted in the selection of three bacteria: Serratia sp. RGM 2525, Raoultella sp. RGM 2526, and Pseudomonas sp. RGM 2607, due to their capacity of producing indole compounds (30-45 μL mL -1 ) and indoleacetic acid (IAA) (5-10 μg mL -1 ). The effect of these strains on the seed germination rate of S. fernandezianum was evaluated under five treatments: individual inoculation of each bacteria, inoculation of a mixture of the three bacteria and a treatment without bacteria (control). Inoculation of bacteria improved the seed germination rate of S. fernandezianum compared to the control treatment, with the bacterial mix as the best treatment with 26.9% germination (p < 0.05), 10.2% higher than control. Bioinoculants formulated with bacteria isolated from rhizosphere soils could improve the seed germination rate of the endangered plant S. fernandezianum.

show abstract

Section: Discussionmentioning

confidence: 99%

Plant growth promoting rhizobacteria from Juan Fernández archipelago improve germination rate of endangered plant Solanum fernandezianum Phil.

Carrasco-Fernández

Guerra

Castro

et al. 2020

Chil. j. agric. res.

View full text Add to dashboard Cite

show abstract

“…These bacteria have been found to be beneficial for the biocontrol of plant pathogens [ 48 – 50 ]. However, many plant growth-promoting rhizobacteria (PGPR) have failed as bioinoculants because of their lack of competitiveness, or because there exists some inhibition between them [ 51 ]. Therefore, our results provide a key finding if future formulations of P .…”

Section: Discussionmentioning

confidence: 99%

Growth inhibition of pathogenic microorganisms by Pseudomonas protegens EMM-1 and partial characterization of inhibitory substances

et al. 2020

View full text Add to dashboard Cite

The bacterial strain, EMM-1, was isolated from the rhizosphere of red maize ("Rojo Criollo") and identified as Pseudomonas protegens EMM-1 based on phylogenetic analysis of 16S rDNA, rpoB, rpoD, and gyrB gene sequences. We uncovered genes involved in the production of antimicrobial compounds like 2,4-diacetylphloroglucinol (2,4-DAPG), pyoluteorin, and lectin-like bacteriocins. These antimicrobial compounds are also produced by other fluorescent pseudomonads alike P. protegens. Double-layer agar assay showed that P. protegens EMM-1 inhibited the growth of several multidrug-resistant (MDR) bacteria, especially clinical isolates of the genera Klebsiella and β-hemolytic Streptococcus. This strain also displayed inhibitory effects against diverse fungi, such as Aspergillus, Botrytis, and Fusarium. Besides, a crude extract of inhibitory substances secreted into agar was obtained after the cold-leaching process, and physicochemical characterization was performed. The partially purified inhibitory substances produced by P. protegens EMM-1 inhibited the growth of Streptococcus sp. and Microbacterium sp., but no inhibitory effect was noted for other bacterial or fungal strains. The molecular weight determined after ultrafiltration was between 3 and 10 kDa. The inhibitory activity was thermally stable up to 60˚C (but completely lost at 100˚C), and the inhibitory activity remained active in a wide pH range (from 3 to 9). After treatment with a protease from Bacillus licheniformis, the inhibitory activity was decreased by 90%, suggesting the presence of proteic natural compounds. All these findings suggested that P. protegens EMM-1 is a potential source of antimicrobials to be used against pathogens for humans and plants.

show abstract

“…The two duckweed extracts were referred to as "filtration" and "autoclaving" and were used in the following amounts; 0% (control), 5%, 10%, and 20% for biofilm formation of strain A6. The crystal violet staining method was used for measuring biofilm formation (Kang et al, 2014;O'Toole and Kolter, 1998).…”

Section: Effect Of Duckweed Extract On Biofilm Formation Of Strain A6mentioning

confidence: 99%

Combination of heterotrophic nitrifying bacterium and duckweed (<i>Lemna gibba</i> L.) enhances ammonium nitrogen removal efficiency in aquaculture water via mutual growth promotion

Shen¹,

Yin

Xia

et al. 2019

J. Gen. Appl. Microbiol.

Self Cite

View full text Add to dashboard Cite

To obtain high aquaculture output, up to 6,500 of fish or 10,000 shrimp are needed per 667 m 2 based on our investigations. As a result, high-protein feeds are needed in these aquatic systems. Urea, liquid cow manure, or even pig manure and chicken manure with high N content are often supplemented during this process (Lin and Yi, 2003; Moav et al., 1977; Soletto et al., 2005; Zoccarato et al., 1995). Budget-wise, about 87% of N comes from feed, while only 1% is released by denitrification (Acosta-Nassar et al., 2010). This results in the generation of substantial amounts of polluted effluent containing unconsumed feed and feces, and thus, leads to an increase in environmental pollution (Crab et al., 2007; Read and Fernandes, 2003). In these kinds of aquatic systems, levels of ammonia-N (NH 3-N), nitrite, and dissolved oxygen (DO) drastically affect aquaculture production (Crab et al., 2007; Zoccarato et al., 1995). Of these factors, NH 3-N is a critical concern; as it leads to an increase in nitrite and a decrease in DO due to the nitrification (Grommen et al., 2002; Kim et al., 2008; Ruiz et al., 2003). In addition, it is toxic for aquatic organisms (Romano and Zeng, 2013; Thompson et al., 2002). The presence of NH 3-N is inevitable, especially during intensive aquaculture, as they are generated from feed residues and manure supplements. Thus, there has been a lot of research trying to develop integrated pond systems using duckweed (Steen et al., 1999; Zimmo et al., 2003) or combined systems with other aquatic organisms such as algae (van der Steen et al., 1998), and cyanobacteria (Duong and Tiedje, 1985). Using the duckweed treatment system, not only NH 3-N, but also bacterial pathogens (El

show abstract

A plant growth-promoting rhizobacteria (PGPR) mixture does not display synergistic effects, likely by biofilm but not growth inhibition

Cited by 18 publications

References 30 publications

Plant growth promoting rhizobacteria from Juan Fernández archipelago improve germination rate of endangered plant Solanum fernandezianum Phil.

Plant growth promoting rhizobacteria from Juan Fernández archipelago improve germination rate of endangered plant Solanum fernandezianum Phil.

Growth inhibition of pathogenic microorganisms by Pseudomonas protegens EMM-1 and partial characterization of inhibitory substances

Combination of heterotrophic nitrifying bacterium and duckweed (<i>Lemna gibba</i> L.) enhances ammonium nitrogen removal efficiency in aquaculture water via mutual growth promotion

Contact Info

Product

Resources

About