The invention discloses a synergist for improving crop resistance and fertilizer absorption capacity. The synergist includes the following components by weight: 20-30 parts of an oyster shell powder, 20-30 parts of a water chestnut skin powder, 10-20 parts of a chinaberry bark powder, 10-20 parts of a magnetic material, 10-20 parts of an illite powder, 5-10 parts of a shiitake mushroom polysaccharide extract. The synergist can, on one hand, improve the resistance of crops, especially reducing the pests and diseases significantly, improving waterlogging and drought resistance； and, on the other hand, greatly reduce the use of fertilizers, especially nitrogen fertilizers, preventing soil compaction. It can also significantly increase the content of active polysaccharides, especially β-glucan in crops. In addition, the raw materials are readily available, the cost is low, and there are significant economic benefits.
