Korean Journal of Soil Science and Fertilizer ISSN:0367-6315(Print) 2288-2162(Online) 한국토양비료학회 학회지

Hydroponic waste solution (HWS) used in greenhouse facilities for horticultural crop production gets discharged into water bodies contributing environmental pollution associated with agriculture. In this study, we evaluated possibility of reusing HWS from paprika cultivation production as fertilizer for paddy rice production. Different concentrations of the HWS were obtained through dilution with irrigation water. Four treatments of C (conventional), T₁ (×10 diluted HWS as a fertigation), T₂ (×20 diluted HWS as a fertigation), T₃ (HWS as a fertilizer at the level of 100% of the standard nitrogen fertilization rate) were used in the study. The preliminary results on the growth of the rice showed significant effect of the different HWS concentrations on the height and number of tillers growth of the rice. Height growth and number of tillers followed similar trends in the order of C > T₁ = T₃ > T₂. At 3 weeks after planting, a significantly high coefficient of correlation (R²) of 0.984 and 0.968 were observed except for T₃ between total nitrogen (N) and plant height; and N and number of tillers respectively. Thus, suggesting total nitrogen contribution from each treatment is a major factor in the growth of the rice. The results at the initial growth stage of the rice suggest, adjusting N concentration in HWS and appropriate timing of HWS application could enable the reuse of HWS in paddy rice production.

Correlation between total nitrogen (N) and growth of rice (height and number of tillers), from May 27th to June 15th. C, conventional; T₁, ×10 diluted HWS as a fertigation; T₂, ×20 diluted HWS as a fertigation; T₃, HWS as a fertilizer at the level of 100% of the standard nitrogen fertilization rate.