insect pests in cotton crop

1. INSECT PEST OF COTTON AND THEIR MANAGEMENT
BY: Aryan Vats,CCSHAU,Hisar

2. (Gossipium hirsutum)
Introduction
It is white gold.
It is also backbone of textile industry.
It’s contributes 7% of GDP our country.
It is providing employment to 60 million people in India.
45% world’s fiber need is met from cotton.
10% of world’s edible oil is met from cotton.

3. IMPORTANCE OF
COTTON
It is cultivated primarily for lint.
Raw cotton is also used for medical and surgical purpose.
Linters are used cushions, pillows etc.
Linters Also used for high grade paper, rayon, films, explosives.
Seed crushed for edible oil.
Cakes and meals are excellent cattle feed.

4. 1. Leafhopper (Amrasca biguttula biguttula )
2. Cotton aphid (Aphis gossypii)
3. Thrips (Thrips tabaci)
4. Whitefly (Bemisia tabaci)
5. Mealy bug (Phenacoccus solani)
1
2
3
45

5. Order: Hemiptera
Family: Cicadellidaes
Distribution and status:
Major pest in all
Host range:
Cotton, potato, brinjal, castor, bhendi, tomato and sunflower.
Leafhopper (Amrasca biguttula
biguttula )

6. Damage symptoms:
Both the nymphs and adults suck sap from the under surface of
leaves.
Tender leaves turn yellow, leaf margins curl downwards .
In the case of severe infestation leaves get a bronze or brick red
colour which is typical “hopper burn”. Crop growth retarded.

7. Adult Nymph
Damaged leaf

8. The adult is wedge-shaped
about 2 mm. long and pale
green in colour.
The front wings have a
black spot on their posterior
parts.
The nymphs are wingless
and are found in large number
on the lower surfaces of
leaves. They walk in diagonal
directions of their body

9. Life cycle
Adult green and wedge shaped, lay eggs singly within leaf veins.
Incubation period 4-11 days.
Nymph light green and translucent found between the veins of
leaves on the under surface.
Nymphal period 7-21 days. Nymphs moult five times.
Life cycle is completed in 15-46 days.
Eleven generations are known to occur in a year.

10. Management
Early sowing and close spacing of cotton reduces pest infestation
particularly if the rainfall is heavy.
Setup light trap to monitor the broods of leaf hopper and to attract
and kill.
Release predators viz., Chrysopa carnea.
Spray monocrotophos 36 SL @ 1000 ml/ha and NSKE 5% @ 25
kg/ha or 750 ml endosulfan 35 EC in 1000 L of water per hectare.

11. Order: Hemiptera
Family: Aphididae
Distribution and status:
India, occasionally serious.
Host range:
Cotton, bhendi, brinjal, chillies, guava
Cotton aphid (Aphis
gossypii )

12. Damage symptoms:
They suck the sap and cause stunted growth, gradual drying
resulting in death of the plants.
In case of severe infestation black sooty mold develops on
honeydew secreted by aphids.
Due to honeydew Photosynthesis is reduced.
Leaf turns down ward curl.
In cloudy weather the infestation is higher

13. Damage symptoms:
Development of black sooty mould due to the excretion of honey dew gives
the plant, a dark appearance.

15. The aphids are greenish brown, soft bodied and small insects.
Apterous females multiply parthenogenitically and viviparously.
A single female may produce 8-22 nymphs in a day which become
adults in about 7-9 days.
Population increase in cloudy weather and in more than 80 % RH

16. Life cycle
Apterous females multiply parthenogenitically and viviparously.
A single female may produce 8-22 nymphs in a day which become
adults in about 7-9 days.

17. Management
Monitor the nymphs and adults of early season sucking pests from
the 14th day after sowing.
Spray any of the following insecticides with 500 L
water/ha.
NSKE 5% kg/ha or Azadirachtin 0.03%.500ml
Methyl demeton 500 ml.
Imidacloprid 17.8 SL 100 -125 ml.
Thiacloprid 21.7 SC 100-125 ml

18. Thrips (Thrips tabaci)
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: hysanoptera
Family:Thripidae
Genus : Thrips
Species : tabaci

19. Thrips are small hemimetabolic insects with a distinctive cigar-
shaped.
They are elongated with transversely constricted bodies .
They range in size from 0.5 to 14 millimetres. but most thrips are
about 1 mm in length.
Thrips have asymmetrical mouthparts that are also unique to the
group.
Unlike the Hemiptera the right mandible of thrips is reduced and
vestigial.
The maxillary stylets and hypopharynx are inserted into the
opening to drain cellular fluid.

21. DISTRIBUTION AND STATUS:
Found world-wide and is found throughout India as a major
pest of cotton.
HOST RANGE:
Cotton, cabbage, cauliflower, potato, tobacco, tomato,
cucumber, brinjal, tea, pine apple, chillies, tomato, radish,
grapes, garlic, onion, etc.

22. DAMAGE SYMPTOMS:
Both nymph and adult lacerate the tissue and suck the sap from
the upper and lower surface of leaves.
in cases of severe infestation they curl upward and become
crumbled.
Heavy feeding on seedlings gives the plants a silvery appearance.
In severe infestations, the terminal buds may be killed.

23. Silvery
appearance

24. LIFE CYCLE
The adults are slender, yellowish brown and measure about 1 mm
in length.
Males wingless, females have long, narrow strap-like wings.
Nymphs resemble the adults in shape and colour but are wingless
and slightly smaller.
This pest is active throughout the year, on breeds of garlic and
onion from November to May.
Migrates to cotton and other summer host plants and breeds till
September.
In October it is found on cabbage and cauliflower.

25. The adult female lives for 2-4 weeks.
Adult female lays 50-60 kidney shaped eggs singly in slits made in
leaf tissue with its sharp ovipositors.
Egg period 4-9 days.
Nymphs pass through two stages and are full fed in 4-6 days.
After which they descend to the ground and pupate at a depth of
about 25 mm.
The pre-pupal and pupal stages last 1-2 and 2-4 days, respectively.
Several generations are completed in a year.

26. 4-9 days
4-6days
2-4 days
1-2 days
Pre pupa
2-4 weeks

27. MANAGEMENT
Monitor the nymphs and adults from the 14th day after sowing.
Use neem coated urea to reduce the infestation of the pest.
Install sky blue colour sticky traps@ 25/ha.
Spray 625 ml of malathion 50 EC or methyl demeton 25 EC.
Spray dimethoate 30 EC or moncrotphos 36 SL 500 ml to750 ml in
500 to 750 L of water per ha as soon as the pest appears. A waiting
period of 7 days should be observed, before harvest.

28. Whitefly (Bemisia tabaci)
Kingdom: Animalia
Phylum:Arthropoda
Class: Insecta
Order:Hemiptera
Family:Aleyrodidae
Genus : Bemisia
Species : tabaci

29. DISTRIBUTION AND STATUS:
India, Sri Lanka,West Africa, Japan and Europe
HOST RANGE:
Cotton, tomato, tobacco, sweet potato, cassava, cabbage,
cauliflower, melon, brinjal and bhendi.

30. DAMAGE SYMPTOMS:
Nymphs and adults suck the sap from the under surface of leaves.
Severe infestation results in premature defoliation, development
of sooty mould, shedding of buds and poor boll opening.
It also transmits the leaf curl virus disease of cotton.
The insect is highly polyphagous.

31. Eggs

32. Adult is a minute insect with yellow body covered with a white
waxy bloom.
Eggs are laid on leaves. Egg period is three days.
Nymph is greenish yellow oval in outline.
Nymphal period is 5-33 days in summer, 17-73 days in winter.

34. MANAGEMENT
Timely sowing with recommended spacing, preferably wider
spacing is essential, avoid late sowing.
Avoid the alternative cultivated host crops of the whitefly (Brinjal,
bhendi, tomato and tobacco) in the vicinity of the cotton crop.
Grow cotton only once in a year either in winter or summer season
in any cotton tract.
Adopt crop rotation with non-preferred hosts such as sorghum and
maize etc., to check the build up of the pest.

35. MANAGEMENT
Spray NSKE 5% and neem oil 5 ml or fish oil rosin soap at 1 kg /
40 L of water
Spray any of the following insecticides with 500 Lwater/ha.
Imidacloprid 17.8 SL 100 -125 ml.
Ethion 50 EC 1. 5-2.0 kg.
Triazophos 40 EC 1.5-2 L.

36. Mealy bug (Phenacoccus solani)
Kingdom: Animalia
Phylum:Arthropoda
Class: Insecta
Order: Hemiptera
Family:Pseudococcidae
Genus : Phenacoccus
Species : solani

37. DISTRIBUTION AND STATUS:
Recently in India the cotton crop in Punjab, Rajasthan, Maharashtra
and Gujarat is being seriously infested with mealy bug
HOST RANGE:
Mealy bug is a polyphagous pest.
It feeds on Ornamental plants, fruit crops, vegetables and field
crops.

38. Nature of damage:
 Growing points become stunted
and swollen
Thick mat with waxy secretion on over
the plants
 Honey dew secretion and develop
black sooty mould
 Both nymphs and adult suck cell sap
 Causing withering and yellowing of
leaves
 Heavy infestation can defoliation and
even death of plants
 It affect the development of flowers
and stems
 In cotton, retarded growth and late
opening of bolls
 Inject saliva that caused curling &
contortion of leaves

40. 42
Mealy bug
Biology:
• It reproduce mostly through Parthenogenesis
• Female lay eggs in cluster on twigs, branches,
• It Contain 600 eggs
• In some species, eggs hatch within the female
and give births live larvae

41. Management
Management
:
• Cultural & Mechanical:
 construct physical barriers like (ants fences)
Remove Crop residues & grasses.
Field boarders should be weed free and free from
debris
Remove alternate hosts of mealy bug
Manual picking of bugs
Apply strong jet of water to remove
Apply sticky bands like Track-trap to prevent crawlers

42. 44
Mealy bug
•Apply methyl parathion 2% dust @ 25 kg/ha in soil
and cultivate.
• In standing crop, apply chloropyriphos @ 2 l/ha
through irrigation.
•Apply methyl parathion 2% dust @ 25 kg/ha on field
boundaries/buds.
•Collect & destroy the leaves/parts of infested plants
and spray any systemic insecticides on those plants.
•Uproot and destroy heavily infested plants carefully
and apply methyl parathion 2% dust on those spots.
Control measures:

43. Integrated Pest Management of cotton pests

44. Cultural Control:
Cultivation of sucking pests tolerant genotypes (Bt-cotton or
non Bt) to help in delay the first spray, thereby conserving the
initial buildup natural enemies.
Intercrops like cowpea, sunflower, marigold, blackgram, to
enhance natural enemies activity and to serve as trap crops.
Regular monitoring of pest after sowing of crop.
Destruction of cotton stalks after final picking is over.
Clean cultivation destroy alternate weed hosts growing on the
field buds

45. Biological Control:
Release of Trichogramma chelonis @ 10 cc/ha in 40 bits/cc or
1,50,000 per hectare.
Conservation of spiders, anthocorids for bollworms management.
Release of Chrysoperla larvae @ 1 larva per plant

46. 4
8
CHRYSOPERLA
Adult
Larva feeding onAphid
Egg
Larvae

47. 49
Lady Bird Beetle
• Adult & larva both
feed on Aphids.
• During larval stage it
consumes 900 –1000
aphids

48. 50
Chemical Control:
The pesticides should be used when absolutely necessary following the
ETL of the majorpests.
ETLs:
Aphids : 20 % infested plants
: 5 aphid / leaf
Jassid: 5 jassids/ leaf or
: 50 jassids / 50 leaves or
: Grade 2 in a scale of 0-4
Thrips : 50 thrips/ 50 leaves or
: 15 % infested plants
Whitefly: 5 whitefly / leaf or
: 20 nymphs/ leaf or
: 10 adults / leaf counted before 9.00 a.m.
Note: When natural enemies are abundantly present, the ETL shouldbe
reaching double of the above figure before application ofpesticides.

49. 51
synthetic
insecticides
Integrated Pest Management ( I P M )
Sr.
No.
Insecticides Dose For which type of insect
pests
1 Monocrotophos36 WSC 0.04% Sucking type
2 Endosulfan 35 EC 0.07% Chewing type
3 Acephate 75 SP 0.075% Sucking type
4 Carbaryl 50 WP 0.2% Chewing type
5 Quinalphos 25 EC 0.05% Chewing type
6 Profenophos 50 EC 0.05% Sucking type (thrips)
7 Chlorpyriphos 25 EC 0.04% Chewing type
8 Triazophos 35 EC 0.04% Sucking type (thrips)
9 Methyl O Demeton 25 EC 0.025% Sucking type
10 Dichlorvos (DDVP) 76 EC 0.05% Sucking type
11 Dimethoate 30 EC 0.03% Sucking type
12 Phenthoate 50 EC 0.1% Sucking type (Mite, Mealy
bug)
13 Fenvalerate 20 EC 0.02% Chewing type
14 Cypermethrin 10 & 25 EC 0.02% Chewing type
15 Deltamethrin 2.8 EC 0.0028% Chewing type & jassid

50. QUESTIONS
Q-1- Hopper bunt in cotton field is due
to___________.
Q-2- Leaf cur disease in cotton is due
to________.
Q-3-Rossete flower is characteristic symptom of
which worm_________.
Q-4-Double seed formation is characeristic
symptoms of which worm_________.
Q-5-Tiny stout bristles is the characteristic feature
of which worm___________.

51. Q-6-Amrasca biguttula is a.
Q-7-Hibernaacula is found in.
Q-8-Trycho card is very effective against control of.
Q-9-Spotted boll worm of cotton pupaes is.
Q-10-Which insect is known as cotton leaf roller?

52. ANSWERS
1- Leaf Hopper.
2- White Fly.
3- Pink Boll Worm.
4- Pink Boll Worm.
5- Spotted Boll Worm.
6- Jassid.
7- Pink Boll Worm.
8-Pod Borer.
9- Out of the boll in a coccon.
10-Sylepta Derogata.