Root response and phosphorus acquisition under partial distribution of phosphorus and water‐soluble organic matter

Understanding how phosphorus and water‐soluble organic matter (WSOM) from animal manure compost contribute to root development is essential for enhancing phosphorus utilization efficiency under their combined application. This study aims to determine mechanisms underlying root responses and phosphorus acquisition based on the partially varying available phosphorus levels in root zone soil following WSOM. The plant growth test was performed using a specifically designed pot where the root elongation was guided into the soil of different root compartments with either phosphorus combined with WSOM or single phosphorus or WSOM. The results revealed high levels of available phosphorus in the root zone soil of individual plants in the presence of WSOM induced small root weight. Phosphorus concentrations in the root exhibited a negative correlation with root weight. Improved root structure development even in the presence of WSOM induced to increase uptake of phosphorus and other nutrients in the plant. Furthermore, a positive linear relationship was observed between nutrient uptake and aboveground dry weight. These findings provide pioneering experimental evidence demonstrating that root development varies to some extent depending on the level of available phosphorus induced by the combined application of phosphorus and WSOM, even within the root zone soil of individual plants. Given that plant growth varied based on partial root development even when phosphorus and WSOM were combined, this study suggests that implementing appropriate phosphorus fertilizer application while considering the augmented availability of phosphorus via the combined application of animal manure compost can promote root development and nutrient uptake, resulting in improved plant growth.