Fungicides have been used to reduce mycotoxin contamination in wheat affected by Fusarium head blight, but most fungicides developed so far have not been sufficiently effective to be useful for managing mycotoxins associated with other diseases has been found that the use of cymoxanil is effective in combatting or preventing fungal diseases. Cymoxanil is a foliar fungicide with protective and curative action. It has Contact and local systemic activity, and it also inhibits sporulation. It can be used for controlling Peronosporales, especially Peronospora, Phytophthora, Plasmopara and Fusarium spp. Chlorothalonil is a chloronitrile non-systemic foliar fungicide with protective action.

1. Fungicide for Plant Disease Management
(Chlorothalonil & Cymoxanil)
Roksana Aftab
Department of Plant Pathology
Sher-E-Bangla Agricultural University

2. Introduction
Diseases are a common occurrence on plants, often having a significant economic impact on yield
and quality, thus managing diseases is an essential component of production for most crops.
Diseases are a major source of crop and plant damage that can be caused by a number of plant
pathogenic (disease-causing) organisms. Fungi often spoil (render unusable) stored fruits,
vegetables, tubers, and seeds. A few which infect grains produce toxins (mycotoxins) capable of
causing severe illness or even death in humans and animals when consumed. Fungicides have been
used to reduce mycotoxin contamination in wheat affected by Fusarium head blight, but most
fungicides developed so far have not been sufficiently effective to be useful for managing
mycotoxins associated with other diseases has been found that the use of cymoxanil is effective in
combatting or preventing fungal diseases. Cymoxanil is a foliar fungicide with protective and
curative action. It has Contact and local systemic activity, and it also inhibits sporulation. It can be
used for controlling Peronosporales, especially Peronospora, Phytophthora, Plasmopara and
Fusarium spp. Chlorothalonil is a chloronitrile non-systemic foliar fungicide with protective
action.
Fungicides for Disease Management
Many fungicides are registered for use on commercially produced plants, but only a few are readily
available to home gardeners. Most fungicides are not restricted in use or categorized as highly
toxic.
Characteristics of Fungicide
1) High yield performance
2) Low phyto-toxicity
3) Stability in storage
4) Stability after dilution to spray strength
5) Low toxicity to human beings and cattle

3. Chlorothalonil
This is another good, general-purpose fungicide for many fungal diseases. It is best as a foliar
treatment as it breaks down rapidly in soil.
Common name: Chlorothalonil
Group Name: Chloronitrile (Group M5)
Trade names: Clortosip, Echo, Rover, Pugil, Mixanil, Fezan plus, Fezan gold, Netor
In Bangladesh: Agrobin 56EC
Registration no.: AP-4628
Name of Registration Holder: Agro Business Support Ltd.
Mode of Action: Chlorothalonil is a non-systemic fungicide with a protective action (fungistasis
and fungicidal action). Anti-resistance strategy.
Category of Fungicide: Wettable powder
Active Ingredient: 98.5% A.I. min.
Formulation of Fungicides:
1. Straight products
a. Chlorothalonil 500 g/L (SC)
b. Chlorothalonil 720 g/L (SC)
c. Chlorothalonil 75% (WG)
d. Chlorothalonil 90% (WG)
2. Ready mixtures
a. Chlorothalonil 375 g/L + Cymoxanil 50 g/L (SC)
b. Chlorothalonil 166 g/L + Tebuconazole 60 g/L (SC)
c. Chlorothalonil 450 g/L + Tebuconazole 50 g/L (SC)
d. Chlorothalonil 233 g/L + Azoxystrobin 68 g/L (SC)
Recommended Dose: 1 ml/L of water
Recommended Diseases: Powdery Mildew (Sweet Gourd, Cereals, Pome fruit, Peanuts, Sugar
beet, Oil seed, Beans)

4. Frequency of Application: Apply this product only through sprinkler irrigation systems including
center pivot, motorized lateral move, traveling gun, solid set or portable (wheel move, side roll,
end tow, or hand move) irrigation system.
Method of Application: Foliar spray.
Time of Application:
 Begin applications during early bloom stage or when disease first threatens and repeat as
necessary (the minimum retreatment interval is 7 days) to maintain control in case of
asparagus.
 Begin applications at first onset of disease, which may occur as early as 2 to 4 weeks before
flowering, and repeat at 7 to 10 day intervals in case of beans.
 In case of corn begin applications when conditions favor disease development and repeat
at 7 day intervals.
Compatibility with other Agro-Chemical: Chlorothalonil, Zoxamide, Fluazinam
Storage and Handling
 Do not contaminate water, food or feed by storage or disposal.
 PESTICIDE STORAGE: Store in original container and keep tightly closed. Store in a cool,
dry place. Protect from excessive heat.
 PESTICIDE DISPOSAL: Pesticide wastes are toxic. Improper disposal of excess pesticide,
pesticide spray or rinsate is a violation of federal law. If these wastes cannot be disposed
of by use according to label instructions, contact your State Pesticide or Environmental
Control Agency, or the Hazardous Waste representative at the nearest EPA Regional Office
for guidance.
 CONTAINER DISPOSAL: Plastic Containers equal to or less than 5 gallons: No refillable
container. Do not reuse or refill this container. Triple rinse container (or equivalent)
promptly after emptying. Triple rinse as follows: Empty the remaining contents into
application equipment or a mix tank and drain for 10seconds after the flow begins to drip.
Fill the container ¼ full with water and recap. Shake for 10 seconds. Pour rinsate into
application equipment or a mix tank or store rinsate for later use or disposal. Drain for 10
seconds after the flow begins to drip.

5.  Offer for recycling, if available, or puncture and dispose of in a sanitary landfill, or by
incineration, or, if allowed by state and local authorities, by burning. If burned, stay out of
smoke.
Precautions in using:
 Follow manufacturer’s instructions for cleaning/maintaining PPE
 Wash hands before eating, drinking, chewing gum, using tobacco or using the toilet.
 Long-sleeved shirt and long pants and chemical resistant gloves made of any waterproof
material.
 Do not enter or allow worker entry into treated areas during the restricted-entry interval
(REI) of 12 hours.
Environmental impacts:
 Chlorothalonil is slightly toxic to mammals, but it can cause severe eye and skin irritation
in certain formulations
 Chlorothalonil and its metabolites are highly toxic to fish, aquatic invertebrates, and marine
organisms.
 Chlorothalonil is practically non-toxic to birds and bees
 In aerobic soils, the half-life for chlorothalonil is from one to three months. Increased soil
moisture or temperature increases chlorothalonil degradation. It is not degraded by sunlight
on the soil surface
 Chlorothalonil is a fairly persistent fungicide on plants, depending on the rate of
application.

6. Cymoxanil
Common Name: Cymoxanil
Group Name: Group 27
Trade Name: Curzate,Dimox 35SC
Registration no.: AP-3924
Name of Registration Holder: Shetu Pesticides Ltd
Mode of action: Cymoxanil is a penetrant fungicide with protectant and curative activity. Its post-
infection activity stops the development of the fungus during the incubation. Local systemic
action: it is able to penetrate the crop leaf and improves the effectiveness of companion fungicides,
especially during periods of intensive disease pressure. Alone, it has a very short period of activity:
two days at most. Therefore it is used in two or in three-way mixtures with protectants and/or
systemic fungicides.
Category of Fungicide: Cyanoacetamide ,Wettable powder
Formulation of Fungicide:
1. Straight products
a. Cymoxanil 45% (WG)
b. Cymoxanil 50% (WG)
2. Ready mixtures
a. Cymoxanil 4% + Mancozeb 40% (WP)
b. Cymoxanil 4,5% + Mancozeb 65% (WP)
c. Cymoxanil 6% + Mancozeb 70% (WP)
d. Cymoxanil 4,5% + Mancozeb 65% (WG)
e. Cymoxanil 2,85% + Copper oxychloride 16% + Phosethyl Al. 30% (WG)
f. Cymoxanil 50 g/L+ Chlorothalonil 375 g/L (SC)
g. Cymoxanil 33% + Zoxamide 33% (WG)
h. Cymoxanil 200 g/L+ Fluazinam 300 g/L (SC)
Active Ingredient: 97% A.I. min.
Recommended Dose: 2 g/L of water, 0.013 mg/kg/day.

7. Recommended Diseases: Early Blight (Tomoto, Potato,Vine.)
Frequency of Application: Fungicides are most effective when they are applied to foliage 1)
before infection occurs or 2) when the disease is in very early stages of development and cannot
be detected yet by the human eye. Later applications are helpful in reducing the rate in which the
disease spreads but are not nearly as effective as early applications. Late blight is very difficult to
manage once infections become established in sprinkler irrigated fields because the microclimate
within the canopy usually favors further disease spread whenever the field is irrigated.The
maximum application rate for foliar applications is 3 oz per acre using a minimum of 20 gals/acre
for conventional ground spray,10 gals/acre for air assisted ground spray, and 5 gals/acre for aerial
spray.
Method of Application: Foliar spray, sprinkler
Compatibility with other Agro-Chemical: Chlorothalonil, Zoxamide, Fluazinam
Precautions in using:
 Follow manufacturer’s instructions for cleaning/maintaining PPE
 Wash hands before eating, drinking.
Environmental impacts:
 Cymoxanil is not acutely toxic to birds.
 Cymoxanil is slightly toxic to fish and other estuarine and marine organisms on an acute
basis.
 Breakdown of Chemical in Soil and Groundwater: Cymoxanil degrades rapidly in the
environment. In sterile, aquaeous environments it degrades rapidly at pH7 or above; at
lower pH it is stable. Soil metabolism studies indicate cymoxanil degrades very rapidly
under both aerobic and anaerobic conditions with half-lives of two days or less.
 Breakdown of Chemical in Surface Water
 Breakdown of Chemical in Vegetation: Cymoxanil degrades rapidly and extensively in
potatoes to natural products.

8. Combination of Chlorothalonil and Cymoxanil
A synergistic fungicidal composition includes cymoxanil and chlorothalonil for preventing and/or
treating fungal infestations in plants and plant parts.
The synergistic fungicidal composition according to the weight ratio of cymoxanil and
chlorothalonil in the composition is in the range of from 25: 1 to 1: 25, preferably the weight ratio
is 1: 7.5
The synergistic fungicidal composition according to wherein cymoxanil is present in an amount
of from 1% to 50% by weight of the composition, preferably from 1% to 25% by weight of the
composition more preferably from 3% to 10%by Weight of the composition, most preferably 5%
by weight of the composition.
The synergistic fungicidal composition according to claim 1, wherein chlorothalonil is present in
an amount of from 1% to 70% by weight of the composition, preferably from 20% by 50% by
weight of the composition, more preferably from 25% to 40% By weight of the composition, most
preferably 37.5% by weight of the composition.
The synergistic fungicidal composition,, wherein cymoxanil and chlorothalonil are present in an
amount of from 1% to 70% by weight of the composition, preferably from 30% to 70% by weight
of the composition, more preferably from 35%to 50% by weight of the composition, most
preferably 42.5% by weight of the composition.
The synergistic fungicidal composition according to any of the preceding claims, the composition
can be diluted with water having the concentration of 250 mL of the composition in 100 L of water.
The synergistic fungicidal composition according to any of the preceding claims, the composition
is in a form of emulsifiable concentrates (EC) , emulsions (EW) , suspension concentrates (SC) ,
oil-based suspension concentrates (OD) , water-dispersible granules ( WG) , water-dispersible
powders (WP) , fine granule (FG) , suspo-emulsions (SE) , microencapsulated suspensions (CS)
or more Suspension concentrates (SC) .
The synergistic fungicidal composition according to any of the preceding claims, the composition
being applied to plants, plant parts and/or surrounding.. The synergistic fungicidal composition

9. according to claim 8, the plants are selected from a group consisting of potatoes, sunflowers,
cucumbers, tomatoes and grape.
The synergistic fungicidal composition according to any of the preceding claims, the composition
is used for treating and/or preventing fungal diseases caused by Plasmopara spp, Phytophthora
spp, Pseudoperonospora spp, and Fusarium spp.
The synergistic fungicidal composition according to any of the preceding claims, the composition
is used for treating and/or preventing fungal diseases caused by Pseudoperonospora cubensis in
cucumber, Plasmopara viticola in grape, Phytophthora infestans in potato, Phytophthora infestans
in tomatoes and Fusarium oxysporum in sunflower And their plant parts.
 Chlorothalonil (30%) + 1 Bounty 36WP AP-3925 Shetu Pesticides Limited Tomato Early
blight 2 g/L of water
 Cymoxanil (6%) 2 Green DT 30EC AP-3926 Complite Source Rice Sheath blight 500 ml
 Selfi 36WP AP-4629 Mimpex Agrochemicals Limited Tea Red rust 1.00 kg
 Cloral 36WP AP-4630 East West Chemicals Limited Tea Red rust 3.00 kg
Conclusion
A combination of cymoxanil and chlorothalonil, characterized by different modes of action
exhibits a potential synergistic effect. A synergistic fungicidal composition includes cymoxanil
and chlorothalonil is effective in preventing and/or treating fungal infestations, particularly
phytophthora spp, Pseudoperonospora spp, Plasmopara spp and Fusarium spp. Cymoxanil may
be present in the synergistic fungicidal composition of the present invention in any suitable
amount, and is generally present in an amount of from 1% to 50% by weight of the composition,
preferably from 1% to 25% by weight of the composition , more preferably from 3% to 10% by
weight of the composition, most preferably 5% by weight of the composition. Cymoxanil and
chlorothalonil may be present in the composition or applied in any amounts relative to each other,
to provide the enhanced or synergistic effect of the mixture. Cymoxanil and chlorothalonil may be
present in the synergistic fungicidal composition in any suitable amount, and is generally present
in an amount of from 1% to 70% by weight of the composition,

10. References
1) McGrath, M.T., 2004. What are fungicides. The plant health instructor, 10, pp.109-115.
2) Fungicide Families or Groups/pnwhandbooks.org/plantdisease/pesticide-
articles/fungicides-disease-management-home-landscape.
3) Registered Pesticides List ,Bangladesh Crop Protection Association (BCPA).
4) Fungicides, OXON ITALIA company.
5) A Pesticide Information Project of Cooperative Extension Offices of Cornell University,
Michigan State University, Oregon State University, and University of California at Davis.
6) (http://pmep.cce.cornell.edu/profiles/extoxnet/carbaryl-dicrotophos/chlorothalonil-
ext.html)
7) Lorsbach, B., Meitl, A., OWEN, W.J. and Yao, C., Dow AgroSciences LLC,
2011. Synergistic fungicidal composition containing 5-fluorocytosine for fungal control in
cereals. U.S. Patent Application 12/871,444.
8) Brix, H.D., Ebersold, D., Semar, M., Bruns, J. and Vonend, M., BASF SE, 2013. Ternary
fungicidal compositions comprising boscalid and chlorothalonil. U.S. Patent 8,349,877.
9) U.S. Environmental Protection Agency. Cymoxanil; Pesticide Tolerance Petition. Federal
Register Document.