1. Seed treatment agent. Chitosan oligosaccharide chitosan can be used as a seed treatment agent for many cereal and vegetable crops, which can stimulate seed germination in advance, promote crop growth, improve disease resistance, and improve the yield of cereal and vegetable. After chitosan treatment, the emergence of cottonseed was one day earlier than that of the control group, and the emergence rate was 13.7% higher than that of the control group. Flowers bloom 2 days in advance, bells end 2 days in advance, flocculation 2 days in advance. There was no significant change in plant height per acre. The output increased by 11.8%. Chitosan is used in seed treatment (soaking, seed dressing, coating) of many kinds of food and vegetable crops, which can promote seed germination, promote crop growth, stimulate disease resistance, and improve yield and quality. In recent years, there are many research results in this field. The mechanism of improving the yield, quality and disease resistance of chitin is under further study. Chitosan can form a protective film on the surface of seeds, which is conducive to maintaining the moisture of seeds to meet the needs of crops. If there is too much water in the soil, it will block the water and prevent the seeds from rotting, which is conducive to seed germination and emergence. It has been reported that treating several crop seeds with different amounts of chitosan, such as wheat, rice and corn, can increase yield. Chitosan can make tea taste more mellow, rice has stronger cold resistance, and can make tomato color more bright.

2. Liquid soil amendment. Chitosan and soluble protein (such as collagen) can be synthesized into liquid soil amendment by using its antibacterial ability and improving soil. The modifier has proper stability and degradability. After degradation, it is a kind of high quality organic fertilizer that can be absorbed by crops. It can inhibit the growth and reproduction of pathogens in the soil, and can effectively improve the soil particle structure, so it is an ideal liquid soil conditioner. Golden chitooligosaccharide indicates that in use, liquid soil amendment sprayed on the soil surface can form a film, so it also has a protective effect. Pesticide or chemical fertilizer can also be mixed into it to make it disperse evenly and achieve sustained release. Soil contains chitosan, which can promote plant growth.