1. Formulation of nitrification inhibitor (1); In addition, the use of these nitrification inhibitors to reduce nitrification, as well as the use of agrochemical mixtures and compounds containing nitrification inhibitors, also includes methods to reduce nitrification, including the treatment of plants, Soil and / or loci contain this nitrification inhibitor and the method of treating fertilizer or the components of this nitrification inhibitor,In the case that the nitrification inhibitor is a compound of formula (1) or its stereoisomer, salt, tautometer or N-oxide, in which a is arilo or hetario, the aromatic ring may not be replaced in each case, or partially or completely replaced by the substitute, each of which is selected, Independently selected from RA, R1 and R2,a. H and C 832131, 832221;R3 is h, haloalkyl c832131;Calcium hydroxide c83216c831832424;e. Among them, the aromatic ring may not be replaced, or partially or completely replaced by the substitute, which can be selected from RB respectively; in RA (I) halogen, CN, nr7491;; r74955;Or758080,SR7580,C (3DY) RC (3DY) ORC (3DY) SRC (3DY) NR RY C (3DY) RY C (3DY) ORY C (3DY) SRY C (3DY) NR RY Y C (3DY) RNR N 3DC (R) (R)C (3DN-OR) RC (3DN-OR) RC (3DN-SR) RC (3DN-NR R) RS (3DO) RNR S (3DO) RS (3DO) Y C (3DY) RS (3DO) Y C (3DY) ORS (3DO) Y C (3DY) SRS (3DO) Y C (3DY) NR RNo.8322;Non-CN alquiler C₁₋₆;C₂₋₆ alkenyl,1. C 83228331 asphalt;C₁₋₄ haloalkyl,C₁₋₄ cyanoalkyl,Calcium hydroxide c83216c831832424;C₁₋₄ alkoxy,C₂₋₄ alkynyl-C₁₋₂ hydroxyalkyl,C₂₋₄-oxy alkynyl; (ii) rent C₁₋₄-C (= Y¹) Rᶜ,alquenilen C -C (3DY) Rrent C₁₋₄-C (= Y¹) ORᶜ,alquenilen C -C (3DY) ORrent C₁₋₄-C (= Y¹) SRᶜ,alquenilen C -C (3DY) SRrent C₁₋₄-C (= Y¹) NRᵃNRᵇ,alquenilen C -C (3DY) NR NR1. C83218331 - 832424248y2-c (= Y1) r758080;alquenilen C -Y -C (3DY) Rrent C₁₋₄-NRᵃRᵇ,alkenyl C₂₋₄-NRᵃRᵇ,rent C₁₋₄-ORᶜ,alkenyl C₂₋₄-ORn,rent C₁₋₄-SRᶜ,alkenyl C₂₋₄-SRᶜ,wherein the C₁₋₄ alkylene or C₂₋₄ alkenylene chain may, in each case, be unsubstituted or may be p