Enhanced nitrification inhibitor composition

Abstract

The present invention relates to an improved nitrification inhibitor composition and its use in agricultural applications.

What is claimed is: 
     
         1 . A microcapsule suspension formulation comprising:
 (a) a suspended phase of a plurality of microcapsules having a volume median particle size of from about 1 to about 10 microns, wherein a microcapsule comprises:
 (1) a microcapsule wall produced by an interfacial polycondensation reaction between a polymeric isocyanate and a polyamine to form a polyurea shell having a wall thickness of from about 10 to about 125 nanometers; and 
 (2) a (trichloromethyl)pyridine compound encapsulated within the polyurea shell; and 
   (b) an aqueous phase.   
     
     
         2 . The microcapsule suspension formulation of  claim 1  wherein the microcapsules have a volume median particle size of from about 1 to about 5 microns. 
     
     
         3 . The microcapsule suspension formulation of  claim 1  wherein the ratio of the suspended phase a) to the aqueous phase b) is from about 1:0.75 to about 1:20. 
     
     
         4 . The microcapsule suspension formulation of  claim 1  wherein the ratio of the suspended phase a) to the aqueous phase b) is from about 1:1 to about 1:7. 
     
     
         5 . The microcapsule suspension formulation of  claim 1  wherein the ratio of the suspended phase a) to the aqueous phase b) is from about 1:1 to about 1:4. 
     
     
         6 . The microcapsule suspension formulation of  claim 1  wherein the polymeric isocyanate is polymethylene polyphenylisocyanate. 
     
     
         7 . The microcapsule suspension formulation of  claim 1  wherein the polyamine is selected from ethylenediamine and diethylenetriamine. 
     
     
         8 . A fertilizer composition comprising: a nitrogen fertilizer and the microcapsule suspension formulation of  claim 1 . 
     
     
         9 . The fertilizer composition of  claim 8  wherein the nitrogen fertilizer is urea ammonium nitrate. 
     
     
         10 . A method of suppressing the nitrification of ammonium nitrogen in growth medium comprising applying the microcapsule suspension formulation of  claim 1  to said growth medium. 
     
     
         11 . The method of  claim 10  wherein the formulation is incorporated into the growth medium. 
     
     
         12 . The method of  claim 10  wherein the formulation is applied to a growth medium surface. 
     
     
         13 . The method of  claim 10  wherein the formulation is applied in combination with a pesticide or sequentially with a pesticide. 
     
     
         14 . The method of  claim 10  wherein the formulation is applied with a nitrogen fertilizer. 
     
     
         15 . The method of  claim 14  wherein the nitrogen fertilizer is urea ammonium nitrate.