Inoculation of microbial spore as a novel approach for enhancing wheat crop growth, resilience, mitigation of climate impacts, and effective biofertilizer development

Phytohormonal impact Nitrogen fixation Nutrient solubilization 2.1.Isolation of spore-forming bacteria was performed on 11 crops from the TUAT field and Fukushima prefecture.Fig. 2. (A) Schematic representation of the experimental flow, illustrating SFB isolation, characterization, and inoculation to wheat under abiotic stress conditions.(B) Stress application schedule. Abiotic stress tolerance:The bacterial tolerance was examined under different pH levels (9, 7.2, and 5) and salt levels (0.5%, 2%, and 4%).2.3.P and K solubilization: NBIRP and Alexandrov medium were used for P and K solubilization, respectively.2.4.Siderphores (Fe) and Indole-3-acetic acid (IAA) production: LB medium + Chrome Azurol S (CAS) and spectrophotometer were used for Fe and IAA production, respectively. Nitrogen fixation ability:To determine the N fixation ability, Ashby's medium (in vitro assay) and acetylene reduction assay (ARA) were examined. Molecular identification:The 16S rRNA, rpoB, and gyrA3 gene were used to identify the promised bacteria.A whole genome sequence was also performed. Plant assays and real-time polymerase chain reaction (RT-PCR):To assess the effects of 13 bacterial PGP strains on wheat crop resilience, an initial plant assay was conducted under control, heat, drought, and heat + drought stress conditions.The top 6 performing isolates from this initial experiment were then selected for a subsequent plant assay.Wheat leaves were harvested for RT-PCR analysis under conditions similar to those in the first experiment.