Roles of phosphate-solubilizing bacteria in mediating soil legacy phosphorus availability

Phosphorus (P), an essential macronutrient for all life on Earth, has been shown to be a vital limiting nutrient element for plant growth and yield. P deficiency is a common phenomenon in terrestrial ecosystems across the world. Chemical phosphate fertilizer has traditionally been employed to solve the problem of P deficiency in agricultural production, but its application has been limited by the non-renewability of raw materials and the adverse influence on the ecological health of the environment. Therefore, it is imperative to develop efficient, economical, environmentally friendly and highly stable alternative strategies to meet the plant P demand. Phosphate-solubilizing bacteria (PSB) are able to improve plant productivity by increasing P nutrition. Pathways to fully and effectively use PSB to mobilize unavailable forms of soil P for plants has become a hot research topic in the fields of plant nutrition and ecology. Here, the biogeochemical P cycling in soil systems are summarized, how to make full use of soil legacy P via PSB to alleviate the global P resource shortage are reviewed. We highlight the advances in multi-omics technologies that are helpful for exploring the dynamics of nutrient turnover and the genetic potential of PSB-centered microbial communities. Furthermore, the multiple roles of PSB inoculants in sustainable agricultural practices are analyzed. Finally, we project that new ideas and techniques will be continuously infused into fundamental and applied research to achieve a more integrated understanding of the interactive mechanisms of PSB and rhizosphere microbiota/plant to maximize the efficacy of PSB as P activators.

Automated summary

Phosphorus (P) is a vital macronutrient for all life on Earth and plays a crucial role in plant growth and yield. However, P deficiency is a common problem in terrestrial ecosystems worldwide. The use of chemical phosphate fertilizer has limitations due to its non-renewable raw materials and adverse effects on the environment. Therefore, finding alternative strategies, such as phosphate-solubilizing bacteria (PSB), to meet plant P demand is important. This article reviews the biogeochemical P cycling in soil systems, explores the use of PSB to alleviate global P resource shortage, discusses the advances in multi-omics technologies, and analyzes the multiple roles of PSB inoculants in sustainable agricultural practices. The authors propose that further research is needed to better understand the interactive mechanisms between PSB, rhizosphere microbiota, and plants in order to maximize the efficacy of PSB as P activators.