Identification of Beneficial Microbial Consortia and Bioactive Compounds with Potential as Plant Biostimulants for a Sustainable Agriculture

A growing body of evidence demonstrates the potential of various microbes to enhance plant productivity in cropping systems although their successful field application may be impaired by several biotic and abiotic constraints. In the present work, we aimed at developing multifunctional synthetic microbial consortia to be used in combination with suitable bioactive compounds for improving crop yield and quality. Plant growth-promoting microorganisms (PGPMs) with different functional attributes were identified by a bottom-up approach. A comprehensive literature survey on PGPMs associated with maize, wheat, potato and tomato, and on commercial formulations, was conducted by examining peer-reviewed scientific publications and results from relevant European projects. Metagenome fragment recruitments on genomes of potential PGPMs represented in databases were also performed to help identify plant growth-promoting (PGP) strains. Following evidence of their ability to coexist, isolated PGPMs were synthetically assembled into three different microbial consortia. Additionally, the effects of bioactive compounds on the growth of individually PGPMs were tested in starvation conditions. The different combination products based on microbial and non-microbial biostimulants (BS) appear worth considering for greenhouse and open field trials to select those potentially adoptable in sustainable agriculture.

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Film coating of seeds with Bacillus cereus RS87 spores for early plant growth enhancement

Canadian Journal of Microbiology ◽

10.1139/w08-079 ◽

2008 ◽

Vol 54 (10) ◽

pp. 861-867 ◽

Cited By ~ 9

Author(s):

Kanchalee Jetiyanon ◽

Sakchai Wittaya-Areekul ◽

Pinyupa Plianbangchang

Keyword(s):

Plant Growth ◽

Bacillus Cereus ◽

Plant Height ◽

Root Length ◽

Film Coating ◽

Field Trials ◽

Growth Enhancement ◽

Vegetative Cells ◽

Plant Growth Promoting ◽

Growth Promoting

The plant growth-promoting rhizobacterium Bacillus cereus RS87 was previously reported to promote plant growth in various crops in both greenhouse and field trials. To apply as a plant growth promoting agent with practical use, it is essential to ease the burden of routine preparation of a fresh suspension of strain RS87 in laboratory. The objectives of this study were to investigate the feasibility of film-coating seeds with B. cereus RS87 spores for early plant growth enhancement and to reveal the indoleacetic acid (IAA) production released from strain RS87. The experiment consisted of the following 5 treatments: nontreated seeds, water-soaked seeds, film-coated seeds, seeds soaked with vegetative cells of strain RS87, and film-coated seeds with strain RS87 spores. Three experiments were conducted separately to assess seed emergence, root length, and plant height. Results showed that both vegetative cells and spores of strain RS87 significantly promoted (P ≤ 0.05) seed emergence, root length and plant height over the control treatments. The strain RS87 also produced IAA. In conclusion, the film coating of seeds with spores of B. cereus RS87 demonstrated early plant growth enhancement as well as seeds using their vegetative cells. IAA released from strain RS87 would be one of the mechanisms for plant growth enhancement.

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Plant Growth-Promoting Microorganisms in Coffee Production: From Isolation to Field Application

Agronomy ◽

10.3390/agronomy11081531 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1531

Author(s):

Narcisa Urgiles-Gómez ◽

María Eugenia Avila-Salem ◽

Paúl Loján ◽

Max Encalada ◽

Leslye Hurtado ◽

...

Keyword(s):

Plant Growth ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Plant Growth Promoting Rhizobacteria ◽

Agroforestry Systems ◽

Field Application ◽

Coffee Production ◽

Coffee Agroforestry ◽

Plant Growth Promoting ◽

Growth Promoting

Coffee is an important, high-value crop because its roasted beans are used to produce popular beverages that are consumed worldwide. Coffee plantations exist in over 70 countries and constitute the main economic activity of approximately 125 million people. Currently, there is global concern regarding the excessive use of agrochemicals and pesticides in agriculture, including coffee crops. This situation has motivated researchers, administrators, and farmers to seek ecologically friendly alternatives to decrease the use of synthetic fertilizers and pesticides. In the last decades, multiple studies of the rhizosphere, at the chemical, physical and biological levels, have improved our understanding of the importance of beneficial microorganisms to plant health and growth. This review aims to summarize the state of the use of plant growth-promoting microorganisms (PGPM) in coffee production, where the most extensively studied microorganisms are beneficial plant growth-promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF). This review also contains information on PGPM, in regard to plantations at different latitudes, isolation techniques, mass multiplication, formulation methods, and the application of PGPM in nurseries, monoculture, and coffee agroforestry systems. Finally, this review focuses on relevant research performed during the last decade that can help us improve sustainable coffee production.

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