Evaluation of Pseudomonas fulva PS9.1 and Bacillus velezensis NWUMFkBS10.5 as Candidate Plant Growth Promoters during Maize-Fusarium Interaction

Abstract

Based on in vitro assessments, molecular and chemical analysis, Pseudomonas fulva PS9.1 and Bacillus velezensis NWUMFkBS10.5 are candidate biocontrol agents for plant disease management including maize fusariosis, a disease caused by members of the Fusarium species. This in vivo study evaluated the bio-protective potential of the aforementioned rhizobacteria strains on maize against the proliferation of the pathogenic fungus Fusarium graminearum (Fg). The study results show that the bacterized plants were not susceptible to Fg aggression and the antagonists displayed the capability to proliferate in the presence of other likely competing microflora. The screen-house data also suggest that the presence of resident soil microbiota impacted the activity of antagonists (PS9.1 and NWUMFkBS10.5). This variation was recorded in the soil treatments (sterilized and unsterilized soil). In all the experimental periods, bacterized maize plants with or without Fg inoculation significantly (p = 0.05) grew better in unsterilized soil. Besides, during the experimental periods, all the consortia treatments with or without Fg infection regardless of the soil used demonstrated appreciable performance. The result of this study suggests that the microbial agents can actively colonize the surface of their maize plant host, improve plant growth, and suppress the growth of phytopathogens. Considering their overall performance in this screen-house evaluation, P. fulva PS9.1 and B. velezensis NWUMFkBS10.5 have potential for field applications. All safety issues regarding their use under field conditions and risks associated with their extended-release into the environmental will, however, be assessed prior to further bioformulation, field investigation, and scale-up.

Prospects of Botanicals and Microbial Bioagents on Seedling vigour of Brinjal vis-a-vis combating Damping off pathogen Pythium aphanidermatum

“…Plant growth enhancement by some plant associated soil microorganisms is related to their ability to act as "biofertilizers" by increasing the availability of nutrients in the rhizosphere of plants (Vessey 2003). Adeniji et. al.…”

The Cultured Microbiome of Pollinated Maize Silks Shifts after Infection with Fusarium graminearum and Varies by Distance from the Site of Pathogen Inoculation

“…One reason for the lack of prior success may be that the biocontrol agents did not originate from, and hence were not adapted to, the tissue and developmental stage relevant to the pathogenic phase of the F. graminearum life cycle-namely, transmitting silks. Furthermore, the current literature points to microbial consortia, rather than individual strains, being integral to a healthy plant microbiome [56,57] and, more specifically, to control Fusarium pathogens [58][59][60][61][62]. Combined, these observations indicate that it may be important to evaluate transmitting silk microbiomes as a whole and employ complex consortia.…”

Community Series in Plants and Microbial Communities: Diversity, Pathogens and Biological Control, Volume II

“…So far, many strains of B. velezensis have been reported to promote plant growth and control diseases in various plants, including shallot, soybean, lotus, walnut, Quercus, Japanese cypress, strawberry, sesame, apple, ginger, pepper, poplar, tomato, grape, tobacco, watermelon, wheat, maize, and cotton Aulia Rahma et al, 2020;Bayisa, 2020;Choub et al, 2021;Ding et al, 2021;Hamaoka et al, 2021;Han et al, 2021;Liang et al, 2021;Masmoudi et al, 2021;Moon et al, 2021;Sachin et al, 2021;Shin et al, 2021;Won et al, 2021;Adeniji and Babalola, 2022;Hong et al, 2022;Yuan et al, 2022). Although B. velezensis has attracted increasing attention as a beneficial microorganism, its application in the control of ornamental flower diseases has not yet been reported.…”