Chitosan Oligosaccharide (COS)

COS is made of quality chitosan, which is extracted from the shell of crabs.


It is an easily-absorbed substance with high solubility after special technological treatment on chitosan. It has excellent water solubility, anti-virus, and antibacterial action. It can start and regulate the immunization of plants at the gene level and induce anti-virus substance production. COS reduces and eliminates the infections of pathogenic agents especially against epiphytes, which are difficult to control. It has no toxicity, no residue, suitable for non-pollution agricultural ecological systems and sustainable development of agriculture.

Chitosan Oligosaccharide (COS) Applications

Foliar Application

• Prevent plant infection from fungal, bacterial and virus-like disease
• Activate and strengthen the plant immune system to improve anti-stress capability, thus, to stimulate crops growth
• As a highly efficient chitosan-activating gene, it replaces other plant hormones to regulate the process of growth

Soil Application

• Have good effects on preventing and killing nematodes
• Can be decomposed by microorganism in soil and improve soil fertility
• Prevent plant infection from fungal, bacterial and virus-like disease

Product Specification

Available Form

1.Chitosan water soluble powder
2.Chitosan technical grade
3.Chitosan Oligosaccharide liquid 10%

Chitosan Oligosaccharide (COS) Functions


Elicitor: Chitosan induces defense reaction in plants, thereby increasing their responses against pathogens attack. Chitin and chitosan are used as elicitors for inducing phytoalexin accumulation. Phytoalexins produced to act as toxins to the attacking organism.
Seed coating: One of the most important bioactivities of chitin and chitosan on plants is the stimulation of seed germination. Chitosan coating alters the permeability of the seed plasma membrane, increasing not only the concentrations of sugars,proline and enzymes activities. Germination rates increase significantly. Seedlings germinate quicker, better, and vigorously.
Leaf coating: Foliar application of chitosan reduces the transpiration of plants by inducing closure of plant stomata.

Plants growth promoter: Chitosan application is strongly effective on the growth and yield of some crops such as potato, cabbage, soybean, pulses, peas, canola, tomato, lettuce, and radish etc. It also has a significant effect on the growth rates of roots, shoots, and flowering.
Bionematicide: Chitosan application in the soil is effective to kill nematodes. It acts by inducing proliferation of chitinolytic microorganisms destroying the cuticle of nematodes and their eggs.
Fertilizer: Chitosan acts as a potent fertilizer due to its high concentration in nitrogen.