Symptoms of crop zinc deficiency: first, it appears in the old leaves, the growth is inhibited, the plants are short, the internodes are broken, the tillers are few or delayed, the leaf veins lose green, and there are albino symptoms. Maize and rice were sensitive to zinc deficiency, followed by dicotyledons potato, tomato and sugar beet; Perennial fruit trees are sensitive to zinc, such as citrus, grape, peach and apple. Zinc deficiency has a great impact on fruit quality.