This document provides information on agrochemicals including their definitions, types, and uses. It discusses the main categories of agrochemicals which are pesticides, synthetic fertilizers, and plant growth regulators. Within pesticides, it describes the types of insecticides, herbicides, and fungicides. It also covers topics like pesticide formulation, application methods, nozzle selection, and safety precautions for handling agrochemicals.

1. Preparation of different
agrochemical doses in field and
pot applications

2. What are agrochemicals?
• Agrochemical or agricultural chemical -
various chemical products used in agriculture.
• It includes
• Pesticides (insecticides, herbicides and
fungicides)
• Synthetic fertilizers
• Hormones and other chemical growth agents

3. Pesticide
• A pesticide is any substance or mixture of substances
intended for preventing, destroying, repelling or mitigating
any pest
• Pests include
– insects,
– plant pathogens,
– weeds,
– molluscs,
– birds,
– mammals,
– fish,
– nematodes and
– microbes
• that destroy property, spread disease or are a vector for
disease or cause a nuisance

4. Insecticide
• A pesticide used against insects
• Includes ovicides and larvicides used against eggs
and insects, respectively
• Use of insecticides is believed to be one of the
major factors behind the increase in agricultural
productivity in the 20th century
• Nearly all insecticides have the potential to
significantly alter ecosystems; many are toxic to
humans; and others are concentrated in the food
chain.

5. Herbicide
• An herbicide, commonly known as a weed killer, is a
substance used to kill unwanted plants
• 2 types- selective and non-selective
• Selective herbicides kill specific targets while leaving the
desired crop relatively unharmed.
• Some of these act by interfering with the growth of the
weed and are often synthetic "imitations" of plant
hormones.
• Herbicides used to clear waste ground, industrial sites,
railways and railway embankments are non-selective and
kill all plant material with which they come into contact.
Smaller quantities are used in forestry, pasture systems, and
management of areas set aside as wildlife habitat.
• Herbicides are widely used in agriculture and in landscape
turf management.
• They account for about 70% of all agricultural pesticide
use.

6. Term Definition Example
Selective
Herbicide formulated to
control specific weeds or
weed categories. A
material that is toxic to
some plant species but
less toxic to others.
2,4-D (Selectively
toxic to broadleaf
weeds)
Non-selective
(a.k.a. Broad
spectrum)
Herbicide formulated to
control both broadleaf and
grass weeds.
Paraquat,
Glyphosate

7. Term Definition Example
Preplant
Herbicides that are applied
before planting the crop -
typically from several days to
just before planting
EPTC,
Glyphosate
Preemergenc
e
Herbicides applied anytime
before the weed seedlings
emerge through the soil surface
Simazine
Postemergen
ce
Herbicides applied after the
crop seedlings (or weed
seedlings) have emerged
through the soil surface
2,4-DB,
bromoxynil
Established
stands
Herbicides applied after the
roots systems have developed
sufficiently enough to allow
selective use.
2diuron, terbacil,
hexazino

8. Fungicides
• Fungicides are chemical
compounds or biological
organisms used to kill or inhibit
fungi or fungal spores.
• Fungicides can either be
systemic or non-systemic.

9. Systemic fungicides
• Systemic fungicides are taken up and redistributed
through the xylem vessels to the upper parts of the
plant. New leaf growth is protected for a short period
• Systemic fungicides act within the plant after being
taken up in the tissue and translocated through the
plant.
• These fungicides can kill a fungus after infection during
incubation (curative control) or with symptoms already
visible (eradicant control).
• Examples are triazoles, SDHI's and QoI’s.
• These are more prone to resistance build up of the
target fungal population.

10. Non-systemic fungicides
• Non-systemic fungicides are not taken up into
the plant tissue, and only protect the plant
where the spray is deposited
• Contact fungicides, like copper, mancozeb and
chlorthalonil act on the outside of the plant
mostly by interfering with spore germination
• They can also have an effect on the growth of
hyphae but won't stop an infection though

11. Fertilizers
• Fertilizers are soil amendments applied to
promote plant growth; the main nutrients present
in fertilizer are NPK (nitrogen, phosphorus and
potassium- the 'macronutrients') and other
nutrients ('micronutrients') are added in smaller
amounts.
• Fertilizers are usually directly applied to soil and
also sprayed on leaves (foliar feeding)
• Primary macronutrients: nitrogen (N), phosphorus
(P), and potassium (K)
• Secondary macronutrients: calcium (Ca), Sulfur
(S), Magnesium (Mg)

12. Fertilizers
• Micronutrients or trace minerals: Boron (B).
Chlorine (Cl), manganese (Mn), iron (Fe), zinc (Zn),
copper (Cu), Molybdenum (Mo) and selenium (Se)
• Macronutrients are consumed in larger quantities and
are present in plant tissue in quantities from 0.2% to
4.0% (on a dry matter weight basis).
• Micronutrients are consumed in smaller quantities
and are present in plant tissue in quantities measured
in parts per million (ppm), ranging from 5 to 200
ppm, or less than 0.02% dry weight.

13. Plant hormones
• Plant hormones (also known as
phytohormones) are chemicals that
regulate plant growth
• These are also termed 'plant growth
substances'
• Plant hormones are signal molecules
produced within the plant, and occur in
extremely low concentrations

14. Plant growth regulators
• The plant growth regulators are simple organic
molecules having several chemical compositions. They
are also described as phytohormones or plant
hormones.
• These plant growth regulators are divided into two
major groups –
1. Auxins, Gibberellins, and Cytokinins are grouped
into Plant growth promoters
2. Abscisic acid and Ethylene are grouped into Plant
growth inhibitors.
• Ethylene may fit in either of these groups.

17. Consumption of pesticides in India

18. Use of Pesticides
•Pesticides play a vital role in controlling
pests and diseases.
•The use of agrochemicals in all contexts is
highly regulated.
•The regulatory framework of pesticides
encompasses national, regional, and
international legislation and conventions that
help assure safety for users, consumers and
the environment.

19. Pesticide formulation
• The biological activity of a pesticide, be it chemical
or biological in nature, is determined by its active
ingredient (AI)
• Pesticide products - very rarely consist of pure
technical material
• AI is usually formulated with other materials and this
is the product as sold, but it may be further diluted in
use
• Formulation improves the properties of a chemical
for handling, storage, application and may
substantially influence effectiveness and safety

20. Pesticide formulation
• Pesticides are manufactured as technical
material which are further processed into
formulations to get even distribution of the
active ingredients over the application area.
• Each formulation has its own special
characteristics.

21. Solid
• Dusts are free flowing powders containing technical
material in the range of 2 to 10 per cent and inert
carrier.
• Granule products contain technical material in the
range of 3 to 10 per cent and granule base.
• Water dispersible powders or Wettable Powders (WP)
are free flowing powders containing technical material
mostly in the range of 25 to 75 per cent, and contain
wetting and dispersing agents and carriers.

22. Liquid
• Water soluble liquids (SL) are liquid formulations
based on technical material which are insoluble in
water and contain 36 to 85 per cent technical
material and solvent.
• Emulsifiable concentrates (EC) are liquid
formulations based on technical material which are
not soluble in water and contain 25 to 80 per cent
technical material, solvent and emulsifier.
• Fumigant formulations used for indoor application
for storage of grains.

23. Other formulations
• Water soluble powders are similar to water
dispersible powders but active ingredient is
insoluble in water.
• Flowable concentrates are slurry like
formulations mixable in water.
• Aerosols are liquids under pressure filled in
cans which on release give a misty spray.
• ULV formulations are liquid formulations
suitable for ultra low volume applications.

26. Significance of symbols on the Pesticide label
Toxicity
category
Acute oral
toxicity LD50
(mg/Kg)
Colour of the
triangle
Signal word
required on
the label
Warning
symbols on
the label
Extremely
toxic
0-50 Red POISON Skull and
cross bones
Highly toxic 51-500 Yellow POISON -
Moderately
toxic
501-5000 Blue Danger -
Slightly toxic 5000 Green Caution -

28. Selection of pesticide
• pesticides need to be selected after consulting the expert if available
locally. Due consideration should be given to the following:
• Efficacy
– Highly toxic to the target pathogen
– Required persistency
– Required spectrum of action
– Required compatibility
• Economy
– Reasonable cost
– Easy availability
– Sufficient storability
• Safety
– Least toxic to mammals and environment
– Relatively safe to beneficial organisms
– Non toxic to crop plants

29. Preparation of spray solution
• To ascertain the quantity of fungicide needed for
required spray solution, following formula is used:
• Quantity of pesticide required (in g/ml) =
• Percentage of solution desired x Quantity of spray
solution required (in ml)
__________________________________________
Given strength of pesticide formulation

30. Example
• If 100 litres of 0.05 per cent malathion is to be
prepared (50 EC), the required quantity of
insecticide can be calculated as:
Quantity of insecticide required (in ml/ml) =
0.05x100 = 5x 100
50 100 x 50
= 0.1l or 0.1x 1000 = 100 ml

31. Example
• If 100 litres of 0.25 per cent mancozeb is to be
prepared from Dithane M-45 (75 % W.P.), the
required quantity of fungicide can be calculated as:
Quantity of fungicide required (in g/ml) =
0.25x100 = 25x 100
75 100 x 75
= 1/3 kg or 0.333 kg or 0.333 x 1000 = 333g

32. Example
• However, in case of fungicides, generally the strength of the
formulated product is generally not considered and the given
strength is always taken as 100 per cent, until and otherwise
desired so and the recommendation is made on a.i. basis.
Therefore, mancozeb required for 100 L of water will be
calculated as follows:
25 x 100 x 1000 = ¼ x 1000 = 250g
100 x 100

33. Procedure
• Mix the measured quantity of the fungicide in
small quantity of water say 5-10 litres in a
separate bucket and put the mixture in the
required water quantity in a bigger container
as per requirement.
• Also add stickers etc. if required in rainy
weather
• Keep stirring the contents with a wooden rod
frequently, so that the fungicidal suspended
particles do not settle down, thereby reducing
the fungicidal concentration.

34. Application of pesticides
• Pesticides are applied by different appliances or methods
based on their formulations and of pathogen attack.
• Pesticide application equipments are available in a variety of
sizes ranging from small to big keeping in view the application
capacity and the source of energy.
• These application equipment may be either manually or
power operated.
• They can be further classified into movable and portable
appliances.
• Movable appliances are those which can be moved around on
wheels or lifted by two or more persons.
• Portable equipments can be carried by one person.
• In the field, knapsack aprayers, foot sprayers, power sprayers
and rotary dusters are used.

35. Pesticide formulations

38. Selection of appliance
Purchase of pesticide appliance
is a long term investment. One
needs to keep in mind the type of
job one wants to handle and
check the appliance for the
following:
•Suitability for the job
•Ease of operation
•Good performance
•Good serviceability
•Easy availability of spare parts
•Reasonable cost

39. Working principle of appliance

40. Types of appliances
•Pesticides are available in various forms. Application equipment
are designed according to the types of formulations to be
sprayed. Application equipment are available in a variety of sizes
ranging from small to big keeping in view the application
capacity and the source of energy.
•These application equipment may be either manually or power
operated. They can be further classified into movable and
portable appliances. By movable is meant that which can be
moved around on wheels or lifted by two or more persons.
Portable means equipment which can be carried by one person.

42. Nozzle
A nozzle performs four basic functions:
•Atomizes liquid into droplets.
•Disperses the droplets in a specific pattern.
•Meters liquid at a certain flow rate.
•Provides hydraulic momentum.
The nozzle tip is one of the most important and
least expensive part of a spraying system.

45. The shape and size of nozzle tip orifice controls the spray angle,
discharge rate and spray pattern. Spray angle influences the swath
of a spray.

46. •Droplet size increases as orifice size increases (for any given
pressure).
•Droplet size decreases with an increase in fan angle (for any given
nozzle size and pressure).

47. When it is desired to spray with more than one nozzle
with the help of a spray Rig or a spray boom, care
should be taken in mounting to avoid overlapping
avoid overlapping or gapping.

48. Pesticides are mostly applied in the form of spray droplets. Droplets produced by
hydraulic nozzle are not uniform in size. Sprays contain both fine and coarse droplets.
They are defined in terms of their diameter and density on the target.
SPRAY DROPLETS

49. Optimum droplet size
• Droplet size is most important for efficient application with minimum
contamination of environment. A 500 micron droplet will contain 1000 times
the Lethal dose of a 50 micron droplet. To reduce wastage, narrow range of
droplet spectrum is essential.
• Coarse droplets are largely influenced by gravitational force and relatively
unaffected by turbulence. Fine droplets will be influenced by wind and
turbulence and have a tendency to drift.

51. Spray application area
The target infested by an insect, pest, disease or weed needs to be sprayed. Generally, the
spray application area differs from the land area except in the case where pre-sowing
treatment is required on soil where land area equals the area to be sprayed. The area required
to be sprayed varies with the distance between the rows of plants, distance between the
plants in the same row and growth of the crop. This is being illustrated diagrammatically.

52. APPLICATION TECHNIQUE
Spray volume: depending upon the volume of spray required per
hectare the application is categorized

53. Maintenance of sprayer
•Sprayer should be well
maintained.
•Clean both inside and outside
the sprayer daily.
•Sprayer should be lubricated
thoroughly.
•All parts should be inspected.
•Filters and nozzles should be
cleaned thoroughly.

54. Precautions Before spraying
Identify the pest and
ascertain the damage
done. Use pesticide
only if it has
exceeded the
economical injury
level. Use only the
recommended
pesticide which is the
least toxic.
Read instructions
manual of the pesticide
and equipment. Check
the spraying equipment
and accessories which
are to be used.
Ascertain that all
components are clean,
especially filling and
suction strainer,
sprayer tank, cut off
device and nozzle.
Test the sprayer and
check the nozzle spray
pattern and discharge
rate.

55. Before spraying
Calibrate the
sprayer. Set
spraying speed
and nozzle swath
by adjusting
spray height and
nozzle spacing.
Make sure that
appropriate
protective clothing
is available and is
used. Ensure that
soap, towel and
plenty of water is
available.
Pesticides
should be kept
in a dry,
locked store.

56. During spraying
Take only sufficient
pesticide for the day’s
application from the
store to the site. Do not
transfer pesticides from
original containers.
Make sure pesticides
are mixed in the correct
quantities.
Wear appropriate
clothing. Avoid
contamination of the
skin especially eyes and
mouth. Liquid
formulation should be
poured carefully to
avoid splashing.
Do not spray in high
wind, high
temperature and rain.
Avoid drift by
selecting proper
direction of spraying
and also holding
nozzle and boom at a
proper height.

57. During spraying
Never eat, drink or
smoke when mixing
or applying
pesticides. Never
nlow out clogged
nozzles or hoses
with your mouth.
Follow correct spray plant
crop thoroughly by
operating sprayer at correct
speed and correct pressure.
Never allow children or
other unauthorized
persons to be nearby
during mixing. Never
leave pesticides
unattended in the field.

58. After spraying
Remaining pesticides
left in the tank after
spraying should
emptied and disposed
off in pits dug in
wasteland. Never
empty the tank into
irrigation canals or
ponds.
Never leave unused
pesticides in sprayers.
Always clean
equipment properly.
After use, oil it and then
keep away in store
room.
Do not use empty
pesticide containers
for any purpose.
Crush and bury the
containers
preferably in a land
filled dump.

59. After spraying
Clean buckets, sticks,
measuring jars etc.
used in preparing the
spray solution.
Remove and wash
protective clothing
and footwear. Wash
yourself well and put
on clean clothing.
Keep an accurate
record of pesticide
usage. Prevent persons
from entering treated
areas until it is safe to
do so. Mark the
sprayed plots with a
flag.