Nanocoated bacteria boost foliar nitrogen fixation in rice

Nitrogen-fixing bacteria can help plants absorb nitrogen through biological nitrogen fixation – a natural process by which bacteria convert atmospheric nitrogen into forms the plant can absorb. Although free-living bacteria can be applied directly to roots and leaves, their potential use in agriculture is underexplored because harsh environmental conditions, particularly in the phyllosphere, are expected to limit their effectiveness. Nanotechnology – particularly nanocoating – offers a promising approach to enhancing bacterial resilience. Write in Natural foodLiao et al. explored a nanocoating strategy to improve the survival and efficiency of nitrogen-fixing bacteria Klebsiella varicella on the leaves of rice plants.

The authors used metal-phenolic networks composed of tannic acid and ferric ions as a strategy to encapsulate Klebsiella varicella. The nanocoating protects bacteria from environmental stressors such as oxidative and thermal stress, as well as ultraviolet exposure. Subsequent addition of the prebiotic sodium alginate almost doubled the biofilm biomass on rice leaves, indicating increased bacterial adhesion and protection against stress.