Oryza - metabolism, Selenium - pharmacology, Solubility, Biological Availability, Oryza - drug effects, Methylmercury Compounds, Mercury - metabolism, Plant Roots - drug effects, Oryza - anatomy & histology, Rhizosphere, Oryza - growth & development, Plant Shoots - metabolism, Plant Shoots - drug effects, Soil - chemistry, Water - chemistry, Plant Roots - an...