Micro-/nanobubble oxygenation irrigation enhances soil phosphorus availability and yield by altering soil bacterial community abundance and core microbial populations
https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2024.1497952/full
Micro-/nanobubble oxygenation irrigation, as a novel irrigation technique,
has been widely utilized to enhance soil phosphorus availability and maize yield.
Nevertheless, currently, most of the studies remain unclear about the precise
mechanism through which micro-/nanobubble oxygenation improves soil
phosphorus availability and maize yield. Therefore, we established two irrigation
methods, conventional irrigation (CF) and micro-/nanobubble oxygenation irrigation
(MB), to investigate the combined effects on enzyme activity, microbial communities,
and soil phosphorus availability in the rhizosphere soil of maize.The results showed
that compared to the CF treatment, the MB treatment significantly increased available
phosphorus content and alkaline phosphatase activity in maize rhizosphere soil
by 21.3% and 15.4%, respectively. Furthermore, MB significantly influenced bacterial
diversity in the maize rhizosphere soil but did not considerably affect fungal
diversity. Specifically, MB regulated the microbial community structure in the
maize rhizosphere by altering the relative abundances of the bacterial phylum
Firmicutes and the fungal phyla Mucoromycota, Chytridiomycota, and Basidiomycota.
In addition, MB reduced the complexity of the bacterial network while increasing the
interaction density among bacterial species. Meanwhile, MB enhanced the complexity
of the fungal network. Structural equation modeling indicated that MB primarily
promoted soil alkaline phosphatase activity by regulating bacterial community
diversity, thereby enhancing soil phosphorus availability. In conclusion, the
application of micro-/nanobubble oxygenation irrigation enhances the activity
of alkaline phosphatasein the soil by modulating the microbial community
within the rhizosphere, thereby facilitating increased phosphorus availability
in the rhizosphere of maize.
This study demonstrates that micro-/nanobubble oxygenation irrigation
effectively increases available phosphorus content and phosphatase activity
in the maize rhizosphere soil. This irrigation management significantly impacts
bacterial diversity while having minimal effects on fungal diversity. By altering
the microbial community structure, micro-/nanobubble oxygenation irrigation
enhances the abundance of key microorganisms that play a crucial role in increasing
available phosphorus levels. The primary factors influencing soil phosphatase activity
are changes in bacterial community diversity and the abundance of core microbial
species. Overall, micro-/nanobubble oxygenation irrigation improves phosphorus
availability by promoting soil alkaline phosphatase activity and supporting beneficial
microbial populations. Thus, this irrigation technique offers a promising approach for
regulating soil microbial communities, enhancing soil phosphatase activity, and improving
phosphorus availability in the maize rhizosphere.
