Antagonism of Two Plant-Growth Promoting Bacillus velezensis Isolates Against Ralstonia solanacearum and Fusarium oxysporum

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Abstract

Plant growth promoting rhizobacteria (PGPR) provide an effective and environmentally sustainable method to protect crops against pathogens. The spore-forming Bacilli are attractive PGPR due to their ease of storage and application. Here, we characterized two rhizosphere-associated Bacillus velezensis isolates (Y6 and F7) that possess strong antagonistic activity against Ralstonia solanacearum and Fusarium oxysporum under both laboratory and greenhouse conditions. We identified three lipopeptide (LP) compounds (surfactin, iturin and fengycin) as responsible for the antimicrobial activity of these two strains. We further dissected the contribution of LPs to various biological processes important for rhizosphere colonization. Although either iturin or fengycin is sufficient for antibacterial activity, cell motility and biofilm formation, only iturin plays a primary role in defense against the fungal pathogen F. oxysporum. Additionally, we found that LP production is significantly stimulated during interaction with R. solanacearum. These results demonstrate the different roles of LPs in the biology of B. velezensis and highlight the potential of these two isolates as biocontrol agents against phytopathogens.

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Bacillus lipopeptides: versatile weapons for plant disease biocontrol.

Marc Ongena, Philippe Jacques (2008)

In the context of biocontrol of plant diseases, the three families of Bacillus lipopeptides - surfactins, iturins and fengycins were at first mostly studied for their antagonistic activity for a wide range of potential phytopathogens, including bacteria, fungi and oomycetes. Recent investigations have shed light on the fact that these lipopeptides can also influence the ecological fitness of the producing strain in terms of root colonization (and thereby persistence in the rhizosphere) and also have a key role in the beneficial interaction of Bacillus species with plants by stimulating host defence mechanisms. The different structural traits and physico-chemical properties of these effective surface- and membrane-active amphiphilic biomolecules explain their involvement in most of the mechanisms developed by bacteria for the biocontrol of different plant pathogens.

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Record: found
Abstract: found
Article: not found

Plant-microbe interactions promoting plant growth and health: perspectives for controlled use of microorganisms in agriculture.

Gabriele Berg (2009)

Plant-associated microorganisms fulfill important functions for plant growth and health. Direct plant growth promotion by microbes is based on improved nutrient acquisition and hormonal stimulation. Diverse mechanisms are involved in the suppression of plant pathogens, which is often indirectly connected with plant growth. Whereas members of the bacterial genera Azospirillum and Rhizobium are well-studied examples for plant growth promotion, Bacillus, Pseudomonas, Serratia, Stenotrophomonas, and Streptomyces and the fungal genera Ampelomyces, Coniothyrium, and Trichoderma are model organisms to demonstrate influence on plant health. Based on these beneficial plant-microbe interactions, it is possible to develop microbial inoculants for use in agricultural biotechnology. Dependent on their mode of action and effects, these products can be used as biofertilizers, plant strengtheners, phytostimulators, and biopesticides. There is a strong growing market for microbial inoculants worldwide with an annual growth rate of approximately 10%. The use of genomic technologies leads to products with more predictable and consistent effects. The future success of the biological control industry will benefit from interdisciplinary research, e.g., on mass production, formulation, interactions, and signaling with the environment, as well as on innovative business management, product marketing, and education. Altogether, the use of microorganisms and the exploitation of beneficial plant-microbe interactions offer promising and environmentally friendly strategies for conventional and organic agriculture worldwide.

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Record: found
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Fruiting body formation by Bacillus subtilis.

S S Branda, J González-Pastor, S Ben-Yehuda … (2001)

Spore formation by the bacterium Bacillus subtilis has long been studied as a model for cellular differentiation, but predominantly as a single cell. When analyzed within the context of highly structured, surface-associated communities (biofilms), spore formation was discovered to have heretofore unsuspected spatial organization. Initially, motile cells differentiated into aligned chains of attached cells that eventually produced aerial structures, or fruiting bodies, that served as preferential sites for sporulation. Fruiting body formation depended on regulatory genes required early in sporulation and on genes evidently needed for exopolysaccharide and surfactin production. The formation of aerial structures was robust in natural isolates but not in laboratory strains, an indication that multicellularity has been lost during domestication of B. subtilis. Other microbial differentiation processes long thought to involve only single cells could display the spatial organization characteristic of multicellular organisms when studied with recent natural isolates.