Assessing wheat growth promotion potential of Delftia lacustris strain NSC through genomic and physiological characterization

BackgroundDelftia sp. has gained considerable attention for its biocontrol and biofertilizer potential to promote the growth of crops such as Oryza sativa, Brassica campestris, and Solanum lycopersicum. However, Delftia sp. supporting wheat plants is yet to be explored. MethodsDelftia strain was cultured from wheat rhizosphere using different growth conditions. The biofertilizer potential of Delftia strain was assessed through physiological, biochemical, genomic, and field experiments. Results and DiscussionPhylogenetic and phylogenomic analysis confirmed taxonomic affiliation with Delftia lacustris. In vitro phosphate solubilization (0.325IU), nitrate reduction (0.401 IU), IAA production (0.485 IU), ACC deaminase activity (0.512 EU), siderophore synthesis properties, and strong antifungal activity against Fusarium oxysporum and Rhizoctonia solani indicated its potential as an effective biofertilizer and biocontrol agent. Drought stress tolerance (up to 40% PEG), metal stress tolerance, salt stress tolerance (up to 11.69% NaCl (w/v), 11.18% KCl (w/v), 4.24% LiCl (w/v)) indicated its survivability even in hostile conditions. Genes for phosphate solubilization (PhoR, PhoB, PhoU, PstABCD), nitrogen fixation (nifC, nifU), auxin production, siderophore biosynthesis, rhizosphere colonization and antifungal properties (chitinase, PhnZ) explains Delftia lacustris bioactivities. Significantly enhanced seed germination (93.33% {+/-} 0.23), seedling growth, and biomass (P <0.05), particularly under stress conditions, indicated plant growth promotion properties of the Delftia strain. Significantly improved plant growth and yield parameters (P=0.0001) in field experiments, highlighting its potential as a biofertilizer and biocontrol agent. ConclusionDelftia lacustris strain NSC1 exhibits multifaceted biofertilizer and biocontrol potential, promoting plant growth, suppressing pathogens, and enhancing stress resilience. Its eco-friendly properties and field efficacy make it a promising alternative to chemical fertilizers for sustainable wheat production.