Self-Assembled Nanocoatings Protect Microbial Fertilizers for Climate-Resilient Agriculture

Abstract

Chemical fertilizers have been crucial for sustaining the current global population by supplementing overused farmland to support consistent food production, but their use is unsustainable. Pseudomonas chlororaphis is a nitrogen-fixing bacterium that could be used as a fertilizer replacement, but this microbe is delicate. It is sensitive to stressors, such as freeze-drying and high temperatures. Here, we demonstrate protection of P. chlororaphis from freeze-drying, high temperatures (50 oC), and high humidity using self-assembling metal-phenolic network (MPN) coatings. The composition of the MPN is found to significantly impact its protective efficacy, and with optimized compositions, no viability loss is observed for MPN-coated microbes under conditions where uncoated cells do not survive. Further, we demonstrate that MPN-coated microbes improve germination of seeds by 150% as compared to those treated with fresh P. chlororaphis. Taken together, these results demonstrate the protective capabilities of MPNs against environmental stressors and represent a critical step towards enabling the production and storage of delicate microbes under nonideal conditions.

Amelioration in nanobiosensors for the control of plant diseases: current status and future challenges

“…Apart from the above advances, nano-coatings on seeds before sowing can protect crops from pest attack and pathogenic microorganisms. Furthermore, metal-phenolic network (MPN)-coated microbes help improve seed germination, build resilience against environmental stressors, and promote beneficial soil microflora under delicate conditions (Burke et al, 2023). Another possible advance in nanotechnology is in food packaging, where nanocomposites can enhance the barrier potential and extent the shelf life of packed foods.…”