Chitosan oligosaccharide is a low-molecular-weight product obtained by degradation of chitosan by lactate which has outstanding water-solubility and high biological activity, thus it can be easily absorbed and utilized by crops. chitosan oligosaccharide has excellent effect on plant diseases defend, More data please check:https://www.doraagri.com/product/chitosan-oligosaccharide/

1. Chitosan oligosaccharide (COS) and Its Application in
Agriculture
By Dora Agri
Institute of Processing Engineering, Chinese Academy of Sciences

2. What is Chitosan oligosaccharide (COS)?
50% NaOH
100℃
5% NaOH
Chitin
5% HClDecalcification
Deproteinization
COS
Acid/enzymatic degradation
Chitosan Chitin
Chitin deacetylase
(EC 3.5.1.41)
COS
Chitosanase
(EC 3.2.1.132)
Chitosan
Protease producing microorganism
Organic acids producing microorganismDecalcification
Deproteinization
Traditional
method
Biological
method
COS（DP, 2-10）

3. Structure and function
DP 6 DP 7 DP 8 DP 9 DP 10
DP 1 DP 2 DP 3 DP 4 DP 5

4. COS and
derivativesAgriculture
Wound
dressing
Fine chemical
Biomedicine
Health food
Foliar
Preservative
Seed
treatment
Skin care and etc. Decreasing blood
glucose, improve gut
health and etc.
Anti-inflammation,
hemostasis and
etc.
Oncotherapy and etc..
Feed
additive
Increasing drug
absorption and etc.
Adjuvant
Application of COS

5. Performance of COS in Agriculture

6. 1、Seed soaking，promote root development, enhance its ability to resist diseases；
2、Leaf spraying at the early tillering stage，promote the efficiency of tiller；
3、Leaf spraying at the early booting stage，increase grain number per spike；
4、Leaf spraying at the full heading stage，maintain a higher boot leaf chlorophyll content, improve the inferior grains filling rate；
Performance of Dora-COS on Rice
Cost : less than 3 dollars per acre
Benefit :
1) more than 50 kg rice per acre;
2) Less amount of NPK fertilizers;
3) Less amount of chemical pesticides;

7. Effect of Dora-COS on pepper
CK
Dora-COS
Surveyed at May 31 Surveyed at Aug 21
Yield
（Kg/acre）
Increasing rate
（%）
Dora-CO S 4365.7±86.8
23.98%
CK 3521.3±121.5
Dora-
COS
C
K

8. Mechanism
research
Dora-COS regulates the accumulation of indole-3-
acetic acid (IAA)
Zhang YH, Du YG et al.,Carbohyd Polym, 2014(113): 446–54;
Zhang YH, Du YG et al.,Plant Physiol Biochem, 2013 (71):49-
56; Guo WH, Du YG et al.,Carbohyd Polym,2012(90):491–95
COS (A); AOS (B); Control (C)
Dora-COSControl
Yield is highly increased
Performance of Dora-COS in promoting growth

9. Performance of Dora-COS in Mango
CK Dora-COS
Dora-COS increases the fruit setting numbers of mango,and thus increases the yield.

10. Regulate the growth of tomato by Dora-COS
Dora-COS increases the total amount of the extra-grade
tomato compared to the control.
Lab experiment performed in Argentina, 210017

11. Fruit setting rate is highly increased
Mechanism research
COS regulates the up-regulation of unsaturated fatty acid
Wang MY, Du YG et al., Field Crops Research, 2015(172): 11–
Performance of Dora-COS in Anti-stress
Treatment Total flower
bud surveyed
Fruit set
numbers
Fruit set rate
（%）
Dora-COS 426 124 29.11
Control（Water） 450 12 2.67

12. Performance of Dora-COS on Chinese tea
12
1)Disease-resistant.
2)Improve quality. The content of tea polyphenols increased 5-10%;
3)Early harvest. 5-7 days earlier than normal management;
4)Reduce residual pesticide. Reduce residual organic pesticides left
on leaves, e.g. pyidaben, chlorpyrifos, fenpropathrin, bifenthrin, and
so on;
5)Increase yield.
Dora-COS
treatment

13. Effect of Dora-COS on Balsam pear
CK
Dora-COS
Field test performed in Hainan,
China
Dora-COS can promote the
health of balsam pear and
protect it from being
attacked by diseases.
Application method:
Spray Dora-COS solution (50 ppm)
on leaves every 14 days

14. Application of COS in insect-resistant
Negative Control
(water)
Positive Control
(dinotefuran)
dora-COS（80ppm）
COS SA
CK 3h
COS SA
CK 5h
Dora-COS induces wild cabbage against whitefly

15. Dora-COS can be applied in Organic Agriculture
COS is environment-friendly;
Good for people;
Good for plants;

16. What is the mechanism of COS？
When COS is applied on
plants, COS will soon be
recognized by some
specific receptors located at
plant cell membranes,
which will bring a series of
defense reactions, including
production of reactive
oxygen species,
phytoalexin biosynthesis,
reinforcement of plant cell
walls, and the accumulation
of pathogenesis related
(PR) proteins, to eventually
resist diseases and stress
from environment.
Carbohydrate polymers, 2010, 82:1-8

17. Science, 2012, 336:1160-1164
Nature, 2006, 444(16):323-329
Nature, 1985, 314(18):615-617
Critical Rev Biotechnol, 2015, 35:29-43
Carbohyd Polym, 2010, 82:1-8
Carbohyd Polym, 2009, 75(4):612-617
Carbohyd Polym, 2011, 86(2):774-82
Plant Cell Rep 2011,30: 1153-62
J. Agric.Food Chem. 2012, 60, 136−143
J Plant P,2007, 89(1): 69-79
Carbohyd Polym, 2012, 90:491-495
Plant Phys Biochem, 2006, 44: 910–916
Carbohyd Polym, 2010, 82:136–142
PNAS, 2007, 104:19613-19618
Plant Cell, 2008, 20:471-481
Phytophathology, 2006, 96:1188-1194
References

18. COS has been applied widely in China,
more than 80,000,000 acre
Application in China
Spectrum of COS in diseases control
1
8

19. In Summary
What is the function of COS on plants？
CO
S
Pathogen
s

20. Contact
Tel: +86-512-52933216
Technical support: lily@doraagri.com
Web: www.doraagri.com