Introduction, methods and control of pests with special reference to pyrethrum, tobacco, and other natural pesticides.

2. PREPARED BY:-
ANEEB ALI 19053
HEMAS MEHMOOD 19050
ABUBAKAR 19054
DANIAL ASIF 19058
MUHAMMAD IBRAHIM
19062
MUHAMMAD AHSAN 19056
PESTICIDES
malikahsan2711@gmail.com
Presented to: Dr. Samia

3. Introduction:
Pest control is a major problem in cultivation of plants throughout the
world.
Pest:
Any animal, insect or plant, fungi, algae, bacteria, virus or anything which
damage the store grains, food stuff, cultivated crops, plants and medicinal plant is
called pest.
Pesticide:
A pesticide is any toxic substance used to kill animal or plants that cause
economic damage to crop or ornamental plants or are hazardous to the health of
domestic animals or humans.

4. Properties of Pesticides:
Pesticides produce their
effect by inhibiting or destroying the metabolic
processes of animals.
All pesticides have their own:
o Mechanism of action
o Potency
o Speed of effect (onset of action)
o Dose required to produce effect

5. Types of Pest:
Animal Pests:
Rodents are responsible for damaging and
destroying medicinal and agricultural
crops.
They spoil and contaminate the crude drugs in
storage.
The spoilage makes crude drugs unsuitable for use in
pharmaceutical industry.
The spoilage and contamination is done by:
o Excretory products
o Hairs
Rodents responsible for damage may be:
o Rabbits
o Rats
o Mice

6. Insects:
More than 1M species of insects are
present in this world.
Out of these, 10K species are responsible for crop
eating.
Out of 10K, only 700 species can cause epidemic
loss to medicinal plants and
crops.
Insects are divided into two groups:
o Biting Insects:
Grass hopper, corn ear worm. They
bite seeds, stem, fruit
and leaves etc.
o Sucking Insects:
Suck instead of biting and examples include
mosquito and
butterflies

7. Plant Pests:
Microorganisms e.g. Bacteria, Fungi and
Viruses
o Bacteria: Xanthomonas causing leave spots

8. • Weeds:
• Undesirable plants in desirable
or cultivated plants.
• Such plants consume minerals; water and
fertilizer given to cultivated plants
• hence inhibit their growth.
• Weeds may also be toxic for example
spores of Agrostemma githago contain
• cyanophore glycoside and which upon
hydrolysis release HCN.

9. Mechanism of Action:
Pesticides kill the pests
in many ways. Each pesticide has its own
mechanism
of action, onset of action, potency and dose
required.
Usually they perform their function by one of the
following ways:
o When ingested kill the pest also called stomach
poison
o When come in contact kill the pest also called
contact poisons
o When inhaled also called fumigants

10. Choice of Chemicals:
The choice of chemical
used to kill the pest depends
o Types of pest
Rodents, herbs or insects
o Habitat of the pest
Indoor or outdoor
If rodents are present indoor, chemical used should be
such that it
should not cause damage to human
Essentials of good Pesticides:

11. For an agent to be a good and ideal pesticide, it should
bear certain important
characteristics as given below.
1. A pesticide should have a high margin of
safety for plants and animal causing
very little or no damage to the foliage or livestock,
respectively.
2. It should be safer.
3. It should be easier to handle and easy for application.
4. It should not show toxicity in case of warm blooded
animals.
5. It should not have flammable or explosive character.
6. It should have safety and palatability of the food
products exposed to
insecticides and should not show the residual effects of
pesticides.
7. It should be available easily at affordable cost.

12. Pesticide Route of Entry:
Dermal (skin) – Most common
Oral
Ocular
Respiratory
Philosophies of Pest Control:
Chemical technology
o Use of chemicals to kill large numbers of the pest
o Short-term protection
o Environmental and health consequences
Ecological pest management
o Control based on pest life cycle and ecology
o Control agent may be an organism or chemical (more on
next slide)
o Specific to pest and/or manipulate a part of the
ecosystem
o Emphasizes protection from pests.

13. Mechanical Method of Pest Control:
Mechanical weed control is any physical activity that inhibits unwanted
plant
growth. Mechanical, or manual, weed control techniques manage weed
populations
through physical methods that remove, injure, kill, or make the growing
conditions
unfavorable.
Mechanical methods include:
Hand Picking
Burning
Trapping
Pruning
A. Hand Picking:
Large caterpillars e.g. a large, green tomato hornworm
larva can be located
rapidly and removed by hand.
Weeds are removed by hand picking.

14. B. Pruning:
Tent caterpillars gather on branches of trees and shrubs, by
pruning or cutting
out such branches of trees is an effective measure.
If the insect’s tent is located near the trunk where the cutting is difficult, then
this part is burnt by a torch or burning oil soaked rags at the end of a long pole.
C. Burning:
Burning helps in destruction of both animal and plant pests
removed by handpicking and pruning.
D. Trapping:
Special traps are used to catch larger field insects, rats and
mice.
Electrified screens specially colored lights and other devices are also
employed
for controlling insects.

15. Biological Method of Pest Control:
Some animal or
insects feed upon smaller forms which destroy the plants while
some insects have a short life cycle which parasitizes larger insects.
For example:
Rabbits are helpful in destroying certain type of weeds.
Cats, owls are enemies of mice and rats
Certain flies and wasps lay eggs on the body of large destructive
insects like
slow moving larvae. The eggs of the parasitic insects hatch rapidly into
smaller
larvae which consume the body tissues of the larger species. Ultimately
the
larger forms die and the parasitized organism is developed into cocoon
stage. It
is emerged as adult fly and begins the cycle once again.

16. Animals and insects which feed upon small forms:
The insects which are used
to control agriculture pest in this manner are called
Entomophagous e.g. red
squill (rat poison) administration cause vomiting in
dogs so they are unaffected.
Red squill administration can not cause vomiting in
rodents so they are died.
Insects with short life cycle and parasitize larger
insects: By taking advantage
of natural phenomenon of life cycle, agricultural
experts have been able to
control certain damaging insects.

17. Chemical Method of Pest Control:
Why are pesticides used in
Agriculture and the Environment?
1. AGRICULTURE:
A. Use of “crop protecting” agents improves yield and quality of
agricultural products.
B. Prevents the spread of diseases to crops and livestock (Pierce’s Disease)
C. The use of pesticides is regulated by the E.P.A. (Environmental Protection
Agency, State law and Country regulation

18. CONTAINERS OR EQUIPMENT
USED FOR CHEMICAL
CONTROL
Spray solutions
Spray suspensions
Baits
Stomach Poisons
Fumigants

19. Concerns with Pesticide Use:
1. ENVIRONMENTAL CONCERNS
a. They kill beneficial insects and plants (non selective).
b. Pollution – run off of herbicides and insecticides into irrigation water and then
into rivers - damages wildlife habitat, kills fish.
c. Cause cancer – organophosphates
d. Disrupt the natural ecosystem and natural biodiversity
e. Creates chemical resistance – insects and weeds.
2. SOCIETY AND ENVIRONMENT:
a. Aesthetics - used regularly in city parks and other recreational areas to control
insect damage and weeds
b. Protect humans from insect-borne diseases; mosquitoes transmit many
diseases, Malaria.
c. Protect our food supply. In developing countries up to 1/3 of all harvested grain
is destroyed by rodents and insects.

20. INTEGRATED PEST MANAGER:
Pest management that utilizes several strategies to control insects and
other
pests rather than strictly relying on chemical control is called IPM. It has 4
components:
1. Pest identification – important for proper pest control
Confuse beneficial insects with harmful (not all bugs are bad!)
Pest that’s on the plant may not be the one causing damage.
Damage may not even be caused by an insect or herbicide- nutritional
deficiency due to weather
2. Surveying for pests – systematically check for pests and pest
damage
Pheromone traps
Sweeping the field
Random leaf, fruit and stem samples
3. Encourage Beneficial Insect/Animal Populations
Use milder chemicals or selective sprays that don’t kill beneficial
animals

21. Examples – “Barn Owl Nesting Boxes” – rodent control
Predatory wasp populations – fly control in poultry and dairy operations
Natural insect enemies – lady bugs
4. Control Action Guidelines:
Application of pesticides only after a certain number of pests have been found
and there is a threat of economic loss
Future Challenges:
IPM – “requires people to work smarter” dealing with biology & ecology and
utilizing
o Environmentally Friendly pesticides
o Mycotoxins – aflatoxins, naturally occurring toxins in peanuts, mushrooms
Organic Farming – now will be regulated by the federal government, fringe
element no more.
Biotechnology – fear of the unknown, no risk is acceptable according to
antibiotech groups.

22. Future of Chemicals & Pesticides:
Alternatives will be Key Issue…not a new concept!
Beneficial insects
Mechanical control
Chemical controls
Hedgerows – create a place for native species- self perpetuating
Cover crops that produce nitrogen…lower fertilizer use
Cover crops that encourage beneficial insects...
Proper irrigation for various crops…reduce runoff
Pesticides Route of Entry:
Dermal (skin) most common
Oral
Respiratory
Ocular
Chemical Technology Problems:
Development of resistance by pests
Resurgences (pest comes back stronger)

23. Secondary pest outbreaks (different pest)
Adverse human health effects
Adverse environmental health effects
Method:
This method utilizes chemicals to control the pest. According to the
type of
pest chemical will be classified:
Rodenticides
Insecticides
Herbicide
Fungicides
Repellents

24. Rodenticides:
RODENTS:
Rodents are mammals like rats, mice, cats, dogs, monkeys etc.
Rodents have been used as food, as pets and as laboratory animals in
research.
Some species, in particular the brown rat, the black rat, and the house mouse
are serious pests, eating and spoiling food stored by humans, and spreading
diseases.
Accidentally introduced species of rodents are often considered to be invasive,
as they sometimes threaten the survival of native species.

25. PROPERTIES OF RODENTICIDES:
Rodenticides are chemicals which are used to kill the rodents.
Rodenticides are incorporated into the feeding stuff of the rodents.
But these must be:
Sufficiently toxic to kill the rodent
Acceptable to the rodents to be ingested in lethal quantities to kill the rodent
EXAMPLE OF RODENTICIDES:
Norbormide
Warfarin
Squill
Nux vomica seeds

26. Insecticides:
Toxic chem·icals used to kill insects are called
insecticides.
Insecticides are classified according to the life
cycle of insects which they
affect.
Nomenclature:
Insecticides are classified based on:
o Specific species
o The stage in the life cycle

27. Stages in the Life Cycle of Insect:
Ovicides (Against the egg stage)
Larvicides (Against the larvae)
Muscicides (Against the house fly)
Pediculicides (Against the body louse)
Scabicides (Against the scabies mite)
Types of Insecticides:
1. Stomach poison
2. Contact poison
3. Repellents

28. 1. STOMACH POISONS:
These are used for insects having biting or chewing mouth parts.
Stomach poisons are applied in the form of solutions or suspensions which are
sprayed on the crops.
A thin layer of poisons remain on the surface of leaves or other plant parts. So
poison is also ingested along with the plant parts, which is absorbed from the
stomach and lead to the death of the insect due to:
o Respiratory failure
o Nervous system depression
METHOD:
Substance is sprinkled over the plants. The resinous material gets attached to
various plant parts. When biting insects eat the plant, toxic material is also taken in.
After ingestion, respiratory failure leads to death.
MAIN STOMACH POISONS:
Acid lead arsenate (for growing plants)
Basic lead arsenate (for growing plants)
Calcium arsenate (For tomatoes, potatoes and cotton)
Sodium fluoride
Thallium sulphate

29. Phosphorous compounds (octamethyl pyrophosphoimide, phosphorous is
absorbed from root and make the plant resistant to pest attack)
2. CONTACT POISONS:
These poisons kill the pest when come in contact with pest.
These poisons penetrate through the skin or cuticle and cause death of the
pest.
Contact poisons are effective against sucking insects and are used in the
form
of residual sprays, dust, aerosols.
Types:
There are two types of Contact Poisons:
Natural contact poisons include Tobacco leaves, pyrethrum flower, and
derris
root.
Synthetic contact poisons include Organic sulphur compounds,
Halogenated
organic compounds, Organic compounds.

30. 3-REPELLENTS:
These are used to protect the attack of insects.
These are used in the form of sprays and aerosols.
For example:
o Citronella oil was used as repellents
o Dimethyl phthalate is used topically on skin
o Diethyl toluamide is effective against mosquito
4. HERBICIDES
These chemicals are used to destroy/kill the weeds (undesirable plants which
grow among the cultivated crops/medicinal plants).
CLASSIFICATION ON BASIS OF SELECTIVITY:
Selective herbicides
Non-selective herbicides
Selective Herbicides:
They selectively eliminate the weeds and have little or no effect on the
cultivated plants. For example:
2, 4 D (2,4-Dichloro phenoxy acetic acid)
2, 4, 5 D (2,4,5-Trichloro phenoxy acetic acid)
Non-Selective Herbicides:

31. These are equally toxic for weeds and cultivated plants. For examples:
Sodium cyanide
Potassium cyanide
Ammonium thiocyanide
CLASSIFICATION ON BASIS OF MODE OF ACTION:
Contact - When the chemicals kill the plants by coming in contact with them
they are called contact herbicides.
Translocated -The systemic or translocated herbicides are chemicals that kill
the plants after their absorption by accelerating or retarding the metabolic
activities of plants.
CLASSIFICATION ON BASIS OF TIME OF APPLICATION:
Pre-plant herbicides -Are applied on the field before planting the crop.
Pre-plant emergence herbicides - Are applied before emergence of weeds.
Past-emergence herbicides - Are applied after the emergence of weeds

32. USE OF HERBICIDES:
Herbicides used to clear waste ground are nonselective and kill all plant
material with which they come into contact.
Some plants produce natural herbicides, such as the genus Juglans (walnuts).
Herbicides are widely used in agriculture and in landscape turf management.
They are applied in total vegetation control (TVC) programs for maintenance
of highways and railroads.
Smaller quantities are used in forestry, pasture systems, and management of
areas set aside as wildlife habitat.
Herbicides have been alleged to cause a variety of health effects ranging from
skin rashes to death.
The pathway of attack can arise from improper applicatrion resulting in direct
contact with field workers, inhalation of aerial sprays, food consumption and
from contact with residual soil contamination.
Herbicides can also be transported via surface runoff to contaminate distant
surface waters and hence another pathway of ingestion through extraction of
those surface waters for drinking.
Some herbicides decompose rapidly in soils and other types have more
persistent characteristics with longer environmental half-lives.

34. 5. FUNGICIDES:
Fungicides are biocidal chemical compounds or
biological organisms used to
kill or inhibit fungi or fungal spores.
Fungi can cause serious damage in agriculture,
resulting in critical losses of
yield, quality, and profit.
Fungicides are used both in agriculture and to
fight fungal infections in
animals.
There are two Types:
o Protectant fungicides
o Eradicant fungicides

35. 1. Protectant Fungicides:
These fungicides are used before the attack of fungus.
Used in the form of sprays.
Seed fungicides are used to eliminate the spores which germinate along with
seeds.
Fungicides are sprayed on wood to protect against the attack.
Bordeaux mixture (Copper sulphate, Water, lime) as a fungicide. It is used in
vineyards, fruit-farms and gardens to prevent infestations fungi.
Other examples are:
o Copper sulphate
o Copper carbonate
o Mercury compound
2. Eradicant fungicides:
These are used after the attack of fungi. For example:
Lime sulphur mixture
Formaldehyde 40%
Quaternary ammonium compounds
Chlorophenol

36. Environmental Method of Pest
Control:
Change of the surrounding environment
Interfere with supply of food
Interfere with the life cycle of the pest
E.g. removal of water or shorten the water supply for mosquito life.
Agricultural Method of Pest Control:
This method includes following measures:
1. DEVELOPMENT OF PEST RESISTANT CROPS:
Involves cultivation of such crops which are resistant to pests.
It may be achieved using biotechnology and genetic engineering.
2. CROP ROTATION:
If the chief source of food of particular insect is withdrawn for one or more
seasons, it will lead to elimination of insects.

37. 3. DEEP PLOUGHING
Deep ploughing will unearth the “GRUB” (state of larvae) and
provides
destruction of insects.
4. GENETIC CONTROL:
Plants or animals are bred to be resistant to the attack of
pests.
o Chemical barriers.
o Physical barriers.
Introduction of genes into crops from other species:
transgenic crops (Bt)
Sterile males are released into pest population

38. Human Health Effects:
Acute:
high dose, short-term response, rapid onset (headache, nausea,
vomiting, respiratory failure, death). Agricultural workers suffer acute
poisoning during pesticide application.
Chronic:
low-dose, long-term exposure, outcome takes many years
before
noticed (cancer, dermatitis, neurological disorder, birth defects, sterility,
endocrine system disruption, immune system depression). Neighborhoods
downwind of agricultural use; farm families; the innocent.

39. Thank you