In vitro assessment of Bacillus subtilis FJ3 affirms its biocontrol and plant growth promoting potential

Abstract

Bacillus species and their metabolites have potential alternative uses as chemical pesticides that can limit the growth of potential plant pathogens and enhance crop productivity. The aim of this study was to investigate the potential of Bacillus subtilis FJ3 for promoting plant growth and controlling fungal plant pathogens. The study evaluated the ability of the strain to promote plant growth in vitro by characterizing its growth-promoting traits, which included the production of hydrolytic enzymes, indole acetic acid, siderophores, biofilm formation, and phosphate solubilization. Polymerase Chain Reaction (PCR) testing revealed that strain FJ3 has the potential to produce lipopeptides such as fengycin, surfactin, mycosubtilin, and pilpastatin. Through in vitro antagonism testing it was demonstrated that strain FJ3 is able to inhibit Fusarium oxysporum by 52% compared to the untreated control and was antagonistic against Aspergillus flavus, Aspergillus niger, and Rhizopus oryzae using a dual method. The minimum inhibitory concentration of Bacillus crude extract resulted in a 92%, 90%, 81.5%, and 56% growth inhibition of Fusarium oxysporum, A. niger, A. flavus, and Rhizopus oryzae, respectively. In FT-IR and GC-MS analysis of crude LPs extract, the transmission and mass spectrum confirmed the existence of aforesaid lipopeptides containing β-fatty acids with chain lengths ranging from C14 to C21 in which the majority were saturated fatty acids. Greenhouse experimentation revealed that Bacillus strain FJ3 and its metabolites significantly diminished the disease incidence with an average reduction of 31.56%. In sterilized soil, FJ3 and its metabolites caused 24.01% and 10.46% growth promotion, respectively, in chickpea. The results demonstrated that Bacillus strain FJ3 has broad-spectrum antifungal and plant growth-promoting applications and could be a promising candidate for development into a commercialized biobased product for use in sustainable agriculture practice.

Bacillus‐derived consortium enhances Ginkgo biloba's health and resistance to Alternaria tenuissima

“…31 Following the application of B. subtilis FJ3 to chickpea, root length increased by 26.2%, shoot length by 36.5%, fresh weight by 27.7% and dry weight by 129.6%. 12 In our experiment, after treatment with the Bacillus mixture via root irrigation, the growth parameters of ginkgo significantly increased, including fresh weight, dry weight, leaf area, leaf thickness, lateral root number and root biomass. In addition, another study found that compound Bacillus biofertilizers promoted root growth and root vitality.…”

“…11 B. subtilis FJ3 and its metabolites caused 24.01% and 10.46% growth promotion in chickpea, respectively. 12 Furthermore, Bacillus can also improve the rhizosphere soil, which in turn can increase plant health. It has been shown that B. paralicheniformis 2R5 increases the quantity of fungi that are helpful to plants, enhancing canola growth and development.…”