Facilitation of phosphorus uptake in maize plants by mycorrhizosphere bacteria

Abstract

A major challenge for agriculture is to provide sufficient plant nutrients such as phosphorus (P) to meet the global food demand. The sufficiency of P is a concern because of it’s essential role in plant growth, the finite availability of P-rock for fertilizer production and the poor plant availability of soil P. This study investigated whether biofertilizers and bioenhancers, such as arbuscular mycorrhizal fungi (AMF) and their associated bacteria could enhance growth and P uptake in maize. Plants were grown with or without mycorrhizas in compartmented pots with radioactive P tracers and were inoculated with each of 10 selected bacteria isolated from AMF spores. Root colonization by AMF produced large plant growth responses, while seven bacterial strains further facilitated root growth and P uptake by promoting the development of AMF extraradical mycelium. Among the tested strains, Streptomyces sp. W94 produced the largest increases in uptake and translocation of 33P, while Streptomyces sp. W77 highly enhanced hyphal length specific uptake of 33P. The positive relationship between AMF-mediated P absorption and shoot P content was significantly influenced by the bacteria inoculants and such results emphasize the potential importance of managing both AMF and their microbiota for improving P acquisition by crops.

How do arbuscular mycorrhizal fungi handle phosphate? New insight into fine‐tuning of phosphate metabolism

“…There is increasing evidence that AM fungi recruit Pi‐solubilizing bacteria (PSB) that secrete organic acid chelators for mobilization of Pi from sparingly soluble salts and/or phosphatases for mineralization of Po (Ordoñez et al ., ; Zhang et al ., ; Battini et al ., ). In the presence of a PSB, R. irregularis released substantial organic carbon that triggered bacterial growth and thus Po mineralization (Zhang et al ., ).…”

“…Pi uptake and translocation of R. irregularis were stimulated in the presence of a Streptomyces sp. isolated from R. irregularis spores, which in turn increased Pi acquisition of the host maize (Battini et al ., ). These experiments were of course conducted under sterilized conditions.…”

Future Phosphorus: Advancing New 2D Phosphorus Allotropes and Growing a Sustainable Bioeconomy

“…While there is evidence of movement from the recalcitrant forms of P to more bioavailable forms with land use management and time (González Jiménez et al, 2019), recent research has found that additions of elements such as silicon (Schaller et al, 2019), arbuscular mycorrhizal fungi (Battini et al, 2017), or phosphate solubilizing bacteria (Adnan et al, 2017) positively affect P mobilization but, in the case of phosphate solubilizing bacteria, may be affected by external factors such as pH and calcium content (Zheng et al, 2019). …”

Phosphorus Nutrition of Plants: A Microbial Perspective

“…bacteria [5] or mycorrhizospheric [9]. They support mycorrhiza and plants by producing plant growth promoting effects, nitrogen fixation, P-solubilization, phytohormones, siderophores and antimicrobials, etc.…”

“…They support mycorrhiza and plants by producing plant growth promoting effects, nitrogen fixation, P-solubilization, phytohormones, siderophores and antimicrobials, etc. [5]. There are countless such interactions in and around plant roots that enhances ultimate uptake of phosphorus by plants.…”