Purple non‐sulphur bacteria and plant production: benefits for fertilization, stress resistance and the environment

<jats:title>Summary</jats:title><jats:p>Purple non‐sulphur bacteria (<jats:styled-content style="fixed-case">PNSB</jats:styled-content>) are phototrophic microorganisms, which increasingly gain attention in plant production due to their ability to produce and accumulate high‐value compounds that are beneficial for plant growth. Remarkable features of <jats:styled-content style="fixed-case">PNSB</jats:styled-content> include the accumulation of polyphosphate, the production of pigments and vitamins and the production of plant growth‐promoting substances (<jats:styled-content style="fixed-case">PGPS</jats:styled-content>s). Scattered case studies on the application of <jats:styled-content style="fixed-case">PNSB</jats:styled-content> for plant cultivation have been reported for decades, yet a comprehensive overview is lacking. This review highlights the potential of using <jats:styled-content style="fixed-case">PNSB</jats:styled-content> in plant production, with emphasis on three key performance indicators (<jats:styled-content style="fixed-case">KPI</jats:styled-content>s): fertilization, resistance to stress (biotic and abiotic) and environmental benefits. <jats:styled-content style="fixed-case">PNSB</jats:styled-content> have the potential to enhance plant growth performance, increase the yield and quality of edible plant biomass, boost the resistance to environmental stresses, bioremediate heavy metals and mitigate greenhouse gas emissions. Here, the mechanisms responsible for these attributes are discussed. A distinction is made between the use of living and dead <jats:styled-content style="fixed-case">PNSB</jats:styled-content> cells, where critical interpretation of existing literature revealed the better performance of living cells. Finally, this review presents research gaps that remain yet to be elucidated and proposes a roadmap for future research and implementation paving the way for a more sustainable crop production.</jats:p>