High-efficiency selenium-rich wheat or rice foliage spray fertilizer

The invention relates to an agricultural product production technique in the field of agricultural fertilizers, particularly a high-efficiency selenium-rich wheat or rice foliage spray fertilizer. The foliage spray fertilizer is composed of the following elements in parts by weight: 1 part of selenium, 2.0-3.0 parts of iron, 0.4-0.6 part of manganese, 0.4-0.6 part of copper, 0.4-0.6 part of zinc, 0.7-0.8 part of magnesium, 1.5-2.5 parts of alkyl polyglucoside, 7.0-8.0 parts of chitosan, 2.6-3.6 parts of sulfur and 0.7-0.8 part of chitosan quaternary ammonium salt. After being sprayed to the wheat or rice foliage, the spray fertilizer can be quickly absorbed by the plant, and can supplement selenium and multiple necessary nutrient elements for plants. The foliage spray fertilizer has the obvious effects of promoting plant growth, reducing the plant diseases, increasing the yield, enriching selenium in the product and the like.