Co-treatment with silicon and quicklime in pig manure application as a promising option of environmnetal management.

Manure utilization is the most important current practices economically and, ecologically. The combined use of active forms of silicon together with other types of soil amendments or fertilizers has been shown to reduce P, N and K leaching from upper soil horizon or fixation, which positively affect crop production. The present study evaluated the performance of pig manure co-treated with quicklime (calcium oxide - CaO) and monosilicic acid (Si(OH)4) as sources of nutrients for rice production conducted in greenhouse and field tests for the reduction of negative environmental effects through the soil-plant system. Results indicated that quicklime/monosilicic acid-treated pig manure reduced the phosphorus and potassium leaching and phosphorus fixation which resulted in an increase in the biomass of rice by 38.3-52.3% in greenhouse and rice yield in field increased by up to 17.4%. Phosphorus plant-availability in the soil and its uptake by rice plants were enhanced by the mixture of treatments. Furthermore, quicklime/monosilicic acid -treated pig manure enhanced the accumulation of potassium in rice leaves.