成果の概要

On-farm cultivation tests were started to verify the differences in the P-dipping effect between the fields in a total of 20 farmer fields with different phosphorus fixing capacities of soils. To clarify the effect of P-dipping on the early growth of rice, plant samples at 60 days after transplanting were collected from 12 selected hills per plot for further shoot analysis. Moreover, canopy photos collected at weekly interval by counterparts were analyzed to assess the P-dipping effect on the development of canopy coverage compared with other treatments. The results of the canopy analysis and biomass sampling highlighted that P-dipping accelerates early growth of rice compared to conventional P application and farmer practices, but the growth rate varies depending on the transplanting times and field conditions. Collected shoot biomass samples were prepared for further analysis of P concentration and P uptake by plant.