The solubility of Zn and the mechanisms that control Zn solubility
may vary with soil properties, such as pH, organic matter content and Clay
Content. A series of laboratory and greenhouse experiments were conducted
to evaluate different forms of added zinc on growth and chemical composition
of rice plant. Results revealed that soluble and exchangeable fraction of zinc
are very small in aU treatments due to the alkalinity of the investigatect so it. It
was noticed that application of Zn (urea). SO. and Zn-EDT A tt urea
increased the extractable fraction of Zn during the incubation perio ,s up to
28days. The extractable fraction of Zn bound with the organic matter
gradually increase during the incubation, considerable amount of the
extractable Zn were observed. It was noticed that application of organic
matter may increase the organic forms of element due to the organic
complexes and lesser extent as inorganic precipitates. Results showed that addition of Zn. CA andlor Zn-EDTA with urea-N
fertilizer increased the grain and straw yield of rice as compared wit ZnSO.
alone. The application of Zn(Urea). SO. with organic matter gave the highest
increase for both grain and straw yield of rice plant as compared with other
treatments. Results revealed that application of organic matter with different
forms of Zn stimulate the grain/straw ratio as compared with other treatments.
Results also revealed that the addition of Zn(Urea). SO. or Zn-EQT A with
organic matter increased N,P and K amounts in the grain and stra'f of rice
plant. The addition of organic matter with different sources of Zn improved the
accumulation of nutrient elements in grain and straw of rice plant. The
availability of Fe, Mn and Zn with organiC matter added were marked y higher
than without organic matter.