Changes in Paddy Soil Properties and Rice Yield as Affected by Application Time of Granular Livestock Manure Compost

Abstract

Pelletized livestock manure compost is easy to handle and thus increasingly used as an orgranic amendment. The effectiveness of granular livestock manure compost (GLMC) was investigated at different times, with 5, 15, 25 and 35 days before transplanting rice plots. After two years of administration of GLMC, pH, available P2O5, exchangeable K, Ca, and Mg decreased and organic matter content increased, compared to the soil before the test. The faster the treatment time of GLMC, the lower the organic matter content. But the T-N was the same in the control, 5 and 15 days before transplanting rice plots. In flooded soil, the N mineralization of GLMC proceeded 2 weeks later than inorganic fertilizers and 1 week later than livestock manure compost. Rice growth and quantity showed similar results in control and 25 days before transplanting rice plot. When GLMC was used, the protein content of white rice was lower than that of control plot, and there was no difference in amylose, whiteness, and palatability. The correlation between the white rice quantity and the treatment time of the GLMC was Y = -0.075X2 + 3.982X + 492.74 (R2 = 0.7722), and the treatment time to obtain the highest quantity of white rice was 26.5 days. Relationship between rice yield and treatment time of granular livestock manure compost.