Nano vanadium-selenium sustained and controlled release fertilizer and preparation method thereof

The invention discloses a nano vanadium-selenium sustained and controlled release fertilizer and a preparation method thereof, and belongs to the technical field of agricultural fertilizer. The nano vanadium-selenium sustained and controlled release fertilizer is prepared by mixing 20-40 parts by weight of ammonium chloride, 10-20 parts by weight of monoammonium phosphate, 10-20 parts by weight of potassium sulfate, 20-40 parts by weight of humic acid, 0.5-1.5 parts by weight of vanadium pentoxide, 0.5-1.5 parts by weight of sodium selenite, 4-8 parts by weight of a natural macromolecular nano carrier shell and 1-3 parts by weight of a coating agent; the nano vanadium-selenium sustained and controlled release fertilizer is good in sustained and controlled release property and high in fertilizer utilization rate, contains moderate amount of vanadium and selenium, can substantially improve the yield and quality of agricultural crops, can increase the fertilizer utilization rate by 10-15%, increases the agricultural crop yield by 10% or more, can effectively reduce the use of chemical fertilizers, reduces the pollution caused by excessive application of the chemical fertilizers, and promotes agricultural scientific and safe fertilization; and produced agricultural products have quite obvious health-care functions of resisting cancer, lowering blood glucose, preventing cardiovascular and cerebrovascular diseases and the like.