A Bacterial Consortium Interacts With Different Varieties of Maize, Promotes the Plant Growth, and Reduces the Application of Chemical Fertilizer Under Field Conditions

Abstract

The success of beneficial bacteria in improving the crop growth and yield depends on an adequate plant-bacteria interaction. In this work, the capability of Azospirillium brasilense Sp7, Pseudomonas putida KT2440, Acinetobacter sp. EMM02, and Sphingomonas sp. OF178A to interact with six maize varieties was evaluated by both single-bacterium application and consortium application. The bacterial consortium efficiently colonized the rhizosphere of the autochthonous yellow and H48 hybrid varieties. Bacterial colonization by the consortium was higher than under single-bacterium colonization. The two maize varieties assayed under greenhouse conditions showed increased plant growth compared to the control. The effect of consortium inoculation plus 50% fertilization was compared with the 100% nitrogen fertilization under field conditions using the autochthonous yellow maize. Inoculation with the consortium plus 50% urea produced a similar grain yield compared to 100% urea fertilization. However, a biomass decrease was observed in plants inoculated with the consortium plus 50% urea compared to the other treatments. Furthermore, the safety of these bacteria was evaluated in a rat model after oral administration. Animals did not present any negative effects, after bacterial administration. In conclusion, the bacterial consortium offers a safety alternative that can reduce chemical fertilization by half while producing the same crop yield obtained with 100% fertilization. Decreased chemical fertilization could avoid contamination and reduce the cost in agricultural practices.

Effects of Abiotic Stress on Soil Microbiome

“…Direct mechanism of PGPR include biofertilization, root stimulation, rhizoremediation, and plant stress control, while antibiosis, induction of systemic resistance and competition for nutrients are the indirect mechanisms of PGPR [32]. It has been shown that, inoculation of beneficial bacteria are able to reduce the use of fertilizer and is a cost effective initiative in reducing the use of agrochemicals [33][34][35]. PGPR such as Burkholderia sp.…”

Comparative Effects of Individual and Consortia Plant Growth Promoting Bacteria on Physiological and Enzymatic Mechanisms to Confer Drought Tolerance in Maize (Zea mays L.)

“…MN-54, Enterobacter, and P. fluorescens 1) as bacterial consortia. In recent years, the co-inoculation of bacterial strains in the same plant has been well reported to stimulate crop growth and development compared to the inoculation of individual bacteria (Mpanga et al 2019;Molina-Romero et al 2021). The functional associative symbiosis in consortium formulations is the key to achieve the beneficial effects of consortia on inoculated plants (Drogue et al 2012).…”

Interaction studies of Serendipita indica and Zhihengliuella sp. ISTPL4 and their synergistic role in growth promotion in rice

“…Among bacteria, actinobacteria are Gram-positive, filamentous bacteria that help in plant growth promotion by increasing the area available for absorption and solubilization of phosphate and by organic recycling, and can also serve as bio-inoculants. Soil actinobacteria release certain chemical compounds that promote plant growth ( Molina-Romero et al., 2021 ; Santoyo et al., 2021 ; Mitra et al., 2022 ; Tsegaye et al., 2022 ). Some research has concluded that microbial combinations are more beneficial than their individual inoculations.…”