成果の概要

Field studies were carried out in two rice-growing areas of Madagascar to assess the effects of phosphorus (P) dipping and other fertilizer practices on rice yield and environmental impact. During the mission, mature rice plots were harvested in sequence at both sites, and grain yields and related growth components were measured at the Radioisotopes Laboratory (LRI). To evaluate the environmental benefits of P-dipping, we collected soil and plant data, focusing on how this technique not only boosts yields in nutrient-poor soils but also reduces environmental load. Additionally, we analyzed root samples to examine changes in root structure caused by P-dipping and how these changes influence rice growth, yield, and sustainability. We also explored a new location with different climate conditions to expand the study of P-dipping's effectiveness and environmental outcomes.