CHANGES IN NITROGEN AND PHOSPHORUS CONCENTRATIONS OF SILICON-FERTILIZED RICE GROWN ON ORGANIC SOIL

Rice grown on the organic soils of the Everglades is routinely fertili zed with silicon (Si). The objective of this research was to investiga te changes in nitrogen (N) and phosphorus (P) concentration in various plant parts in response to Si fertilization. Two cultivars were grown in lysimeters filled with low-Si soil. Half the lysimeters were ferti lized with calcium silicate to provide 2Mg Si ha(-1) and the other lys imeters remained unfertilized as a control. Nitrogen concentration dec reased in all plant parts with Si fertilization. Phosphorus concentrat ion increased with Si. Maturity was earlier in the Si fertilized rice.