Wan, H., Hou, J., Wei, Z. et al. Contrasting maize responses to soil phosphorus and potassium availability driven by biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More under reduced irrigation. Plant Soil (2024). https://doi.org/10.1007/s11104-024-06824-2

Biochar has gained attention for its ability to improve soil water retention and fertility. However, its effects on soil nutrients, particularly phosphorus (P) and potassium (K), need more comprehensive investigation. This study aimed to explore how biochar influences the availability of these nutrients and their impact on maize growth, especially under conditions of reduced irrigation.

Researchers conducted experiments with maize plants grown in split-root pots under three irrigation regimes: full irrigation (FI), deficit irrigation (DI), and alternate partial root-zone drying (PRD). Two types of biochar were used: softwood biochar (SWB) and wheat-straw biochar (WSB), each added at 2% (w/w). The study spanned three consecutive growth cycles.

The findings revealed that WSB reduced soil P availability, leading to lower P content in plants. However, WSB significantly increased soil K availability, resulting in higher plant K content. This increase in K content enhanced maize biomassBiomass is a complex biological organic or non-organic solid product derived from living or recently living organism and available naturally. Various types of wastes such as animal manure, waste paper, sludge and many industrial wastes are also treated as biomass because like natural biomass these More and the harvest index, particularly under the PRD irrigation regime. WSB also improved P use efficiency by reducing plant P content while increasing biomass during the initial growth cycles. Conversely, SWB reduced plant growth under reduced irrigation due to inhibited K uptake, though PRD helped mitigate this by promoting root growth.

In conclusion, while WSB negatively affected soil P availability and plant P content, its combination with PRD irrigation shows promise for sustainable maize production under drought conditions. This strategy could enhance plant growth and resilience by improving K availability and use efficiency.